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Overweight and Obesity Among Adults With Intellectual Disabilities Who Use Intellectual Disability/Developmental Disability Services in 20 U.S. States
Roger J. Stancliffe University of Sydney, Australia
K. Charlie Lakin and Sheryl Larson Research and Training Center on Community Living, University of Minnesota
Joshua Engler, Julie Bershadsky, and Sarah Taub Human Services Research Institute, Cambridge, MA
Jon Fortune Human Services Research Institute, Tualatin, OR
Renata Ticha Research and Training Center on Community Living, University of Minnesota
Abstract The authors compare the prevalence of obesity for National Core Indicators (NCI) survey participants with intellectual disability and the general U.S. adult population. In general, adults with intellectual disability did not differ from the general population in prevalence of obesity. For obesity and overweight combined, prevalence was lower for males with intellectual disability than for the general population but similar for women. There was higher prevalence of obesity among women with intellectual disability, individuals with Down syndrome, and people with milder intellectual disability. Obesity prevalence differed by living arrangement, with institutional residents having the lowest prevalence and people living in their own home the highest. When level of intellectual disability was taken into account, these differences were reduced, but some remained significant, especially for individuals with milder disability.
DOI: 10.1352/1944-7558-116.6.401
Overweight and obesity are associated with increased mortality and morbidity (Berrington de Gonzalez et al., 2010; Manson & Bassuk, 2003; Soverini et al., 2010). Obese individuals had a significantly higher mortality rate in a large sample of people with Down syndrome (Yang et al., 2002).
Among U.S. adults in the general population, the prevalence of obesity (body mass index [BMI]
$ 30.0) and overweight and obesity (BMI $ 25.0) in 2007–2008 was 33.8% and 68.0%, respectively (Flegal, Carroll, Ogden, & Curtin, 2010). There were important prevalence differences by gender, age group, and race–ethnic group. Obesity preva- lence among U.S. adults increased from 13%–15% in the 1960s and 1970s to 31% in 2000, but the rate of increase may now be leveling off (Flegal et al.).
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Prevalence of obesity among adults with intellec- tual disabilities also increased between the mid- 1980s and 2000 (Rimmer & Yamaki, 2006; Yamaki, 2005).
Adults With Intellectual Disabilities Compared With the General Community
Two reviews of obesity research identified a higher prevalence of overweight and obesity among adults with intellectual disability than in the general community (Melville, Hamilton, Hankey, Miller, & Boyle, 2007; Rimmer & Yamaki, 2006). Several studies have supported this conclusion, both for users of formal intellectual and developmental disabilities services and for population samples that include many individuals with intellectual disabil- ity living outside the formal service system (Mel- ville et al., 2008; Yamaki, 2005). However, other studies have found more limited differences (Bhaumik, Watson, Thorp, Tyrer, & McGrother, 2008; Emerson, 2005).
Yamaki (2005) used national population sam- ples from the annual National Health Interview Survey (NHIS) to compare BMI based on self- reported height and weight (for individuals unable to respond, another adult household member could provide the information) of adults with intellectual disability and adults from the general population. The NHIS is a household sample survey of the health status of the U.S. ‘‘noninsti- tutionalized’’ population and includes adults with intellectual disability living with family members or in their own homes but generally excludes persons living in formal service settings. This likely yields more individuals with mild or moderate intellectual disability and fewer comorbid physical, health, and mental health conditions. Yamaki’s operational definition of intellectual disability in- cluded only people who reported a substantial functional limitation and mentioned ‘‘mental retardation’’ as the cause. This definition may not include people who report Down syndrome, autism, cerebral palsy, and other intellectual or developmental disabilities (Hendershot, Larson, Lakin, & Doljanac, 2005).
Compared with the general population, Yamaki (2005) found a higher percentage of adults with intellectual disability in the obese category but no significant overall differences for the overweight category, although men with intellectual disability
had significantly lower prevalence of overweight than men in the general population. In the most recent period examined (1997–2000), 34.6% of adults with intellectual disability were obese com- pared with 20.6% of adults (aged 18–65 years) from the general population, whereas 28.9% (intellectual disability) and 34.1% (general population) were overweight (BMI 5 25.0–30.0). Yamaki’s samples of adults with intellectual disability were moderately sized (range 5 650–1,098), although the most recent sample (1997–2000) of 650 participants yielded relatively large confidence intervals (6 8.0%). Therefore, subgroup analyses were only possible for gender and age group separately, with no examination of race–ethnicity.
Several larger scale and/or population-based studies of BMI have focused on adults with intellectual disability living outside the United States. Overweight and obesity may vary by nation, both for the general population and for those with intellectual disability, with higher prevalence among U.S. individuals (Harris, Rosenberg, Jangda, & Gallagher, 2003; Sassi, Cecchini, & Devant, 2010). Therefore, caution is warranted when reviewing research findings on BMI for persons with intellectual disability from other countries for relevance to U.S. populations.
Emerson (2005; N 5 1,304) found that 14% of disability-accommodation service users in northern England were underweight, 28% over- weight, and 27% obese. Prevalence of obesity among men with intellectual disability did not differ significantly from English men without intellectual disability, except that men with intellectual disability aged 65–74 years had significantly lower obesity rates than men of the same age from the general population. However, women with intellectual disability had higher prevalence of obesity in several age groups and did not differ from women without intellectual disability in other age groups.
Bhaumik et al. (2008; N 5 1,119) examined all individuals on a register of adults with moderate, severe, or profound intellectual disability in a de- fined geographical area in Leicestershire, England. They found that 20.7% of adults with intellectual disability were obese and an additional 28.0% were overweight. The overall intellectual disability sample did not differ significantly from the general popu- lation in England in the prevalence of obesity. Compared with men in the general population (19% obesity prevalence), men with intellectual disability (15% obesity prevalence) had nonsignificantly lower
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prevalence of obesity. Women with intellectual disability, however, had significantly higher preva- lence of obesity (32%) than women in the general population (23%).
Gender
There is higher prevalence of obesity among women with intellectual disability compared with men with intellectual disability (Bhaumik et al., 2008; Emerson, 2005; Melville et al., 2007, 2008; Robertson et al., 2000; Yamaki, 2005). Melville et al. (2007) concluded that, relative to the higher rate of obesity in women in the general popula- tion, among people with intellectual disability, ‘‘the gender effect is accentuated, placing women with intellectual disabilities at particular risk’’ (p. 225).
Diagnosis and Level of Intellectual Disability
Among adults with intellectual disability, there are important differences in BMI related to diagnosis. Individuals with Down syndrome are more likely to be overweight or obese than other individuals with intellectual disability (Bhaumik et al., 2008; Hove, 2004; Melville et al., 2007, 2008; Rubin, Rimmer, Chicoine, Braddock, & McGuire, 1998; Robertson et al., 2000; Stancliffe et al., in press). Lower prevalence rates of overweight and obesity are evident for adults with cerebral palsy (Bhaumik et al., 2008; Stancliffe et al., in press).
Likewise, level of intellectual disability has been associated with BMI status. Individuals with milder disability have a higher prevalence of obesity, whereas those with more severe disability have a lower rate of obesity but a higher prev- alence of underweight (Emerson, 2005; Hove, 2004; Melville et al., 2007, 2008; Robertson et al., 2000).
Living Arrangements
Living arrangements appear to be related to BMI, with a higher prevalence of obesity evident in less restrictive settings (own home, family home), and lower prevalence in more regulated, fully supervised settings (Melville et al., 2007; Rimmer & Yamaki, 2006). However, not all the studies reporting such findings controlled for differences in personal characteristics between living arrangements. For example, although Lewis,
Lewis, Leake, King, and Lindemann (2002) reported significant differences in level of intel- lectual disability by living arrangements, the lower prevalence of obesity in community group-care facilities may be attributable to the much more severe level of intellectual disability of residents in these settings compared with those living on their own or with family members. When Melville et al. (2008) used multivariate analysis that controlled for level of intellectual disability, they found a significant effect of living arrangements for Scottish women (women living independently were more likely to be obese than those living with family), but no effect for Scottish men. In addition, Melville et al. found no significant multivariate difference by living arrangements for either gender on prevalence of overweight.
Purpose of This Article
The goal of this article is to report on the prevalence of obesity and overweight among adult users of U.S. intellectual disability/developmental disability services in a large sample drawn from the 2008–2009 National Core Indicators (NCI) program and compare these findings to preva- lence data for the general population from Flegal et al.’s (2010) findings from the 2007–2008 National Health and Nutrition Examination Survey (NHANES), with subgroup analysis by age, gender, and race–ethnicity. In addition, we provide descriptive information about BMI of adults with intellectual disability and compare BMI status and obesity prevalence among indi- viduals with different syndromes related to intellectual disability, with different levels of intellectual disability, and with different living arrangements.
Method
Participating States The NCI program is a voluntary collabora-
tion between the National Association of State Directors of Developmental Disabilities Services, the Human Services Research Institute, and state developmental disability agencies of participating states. No NCI data are collected in nonpartici- pating states.
The 8,911 sample members in this study were drawn from all 20 states that participated in the 2008–2009 NCI program and collected con- sumer survey data. Participants were adult users of
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developmental disabilities services in Alabama, Arkansas, Connecticut, Delaware, Georgia, Illinois, Indiana, Kentucky, Louisiana, Massachusetts, Mis- souri, North Carolina, New Jersey, New York, Ohio, Oklahoma, Pennsylvania, South Carolina, Texas, and Wyoming. Within each participating state, samples were randomly drawn from the state’s population of adults (age $ 18 years) with intellectual disability receiving institutional, com- munity, or home-based services, or some subset of these (a few states’ samples included only recipients of home and community-based services). Sample sizes in participating states ranged from 193 (DE) to 1,502 (NY) and averaged 578.
Instrument Data were collected using the 2008–2009 NCI
Consumer Survey. The 2008–2009 survey was the first version of the NCI survey to obtain data on height and weight, allowing BMI to be calculated. Height and weight data were not measured directly by NCI interviewers but were obtained typically from individual records, setting admin- istrators, or support providers (including family members for participants living with family). These informants provided data on height in feet and inches and data on weight in pounds. These data are reported in the NCI Background section, which requests information on the service user’s personal characteristics, functioning, level of intellectual disability, diagnoses, health, problem behavior, living arrangements, and services. Data in this section are typically obtained from agency records, and it is usually completed by a case manager–service coordinator.
One item asks whether the person has a diagnosis of intellectual disability. The next item asks about the person’s level of intellectual disability (respondents may check one of the following: N/A [not applicable], mild, moderate, severe, profound, unspecified, or unknown). The item that follows asks about a list of 16 other disabilities and diagnoses that are noted on the person’s record (respondents may check all that apply), including autism spectrum disorder, cere- bral palsy, Down syndrome, and Prader-Willi syndrome. The residence-type item provides respondents with 10 response options: specialized institutional facility for persons with intellectual disability/developmental disability, group home, agency-operated apartment, independent home or apartment, parent–relative’s home, foster care or
host home (person lives in home of unrelated, paid caregiver), nursing facility, homeless, other, or ‘‘don’t know.’’ There is also an item on the number of people with disabilities living at the setting, which can be used to cross-check resi- dence type (e.g., an institution is considered to house 16 or more people with a disability). No specific distinction is made between intermediate care facility for people with ‘‘mental retardation’’ (ICFs/MR) and settings with other funding or regulatory arrangements, in that ICFs/MR can be classified as institutions ($16 residents) or group homes (#15 residents), but group homes also include non-ICF/MR settings.
Interviewer training. To ensure that all inter- viewers received consistent training, the NCI Consumer Survey protocol is supported by a training program for interviewers, including training manuals, presentation slides, training videos, scripts for scheduling interviews, and lists of frequently asked questions. The training includes question-by-question review of the sur- vey tool.
Reliability. Multiple tests of the NCI instruments have yielded interrater agreement of 92%–93%, and a single examination of test–retest reliability resulted in 80% agreement (Smith & Ashbaugh, 2001). How- ever, no item testing was done on the specific height and weight variables.
Participants The total 2008–2009 NCI sample consisted
of 11,569 individual users of adult intellectual disability/developmental disability services from 20 states. We excluded 99 people whose age was missing and another 208 sample members aged 18 or 19 years, because our general population comparison sample only included adults aged 20 or older (Flegal et al., 2010). Because we also wanted to compare our sample with the compar- ison sample on gender, race, and age, we excluded individuals with missing data on these variables. In addition, we excluded 421 individuals whose height was missing and 13 adults with recorded heights of 36 inches or less or 84 inches or more. Such listed heights were, of course, possible but were notable outliers, and we had no means to follow up on their accuracy. Last, we omitted individuals without an intellectual disability diagnosis because our focus was on BMI in adults with intellectual disability. This selection process yielded a final sample of 8,911 individuals from
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20 states, with an average age of 43.48 years (range 5 20–93 years).
The U.S. general population comparison data, including breakdowns by gender and race, were drawn from analyses of the NHANES by Flegal et al. (2010). To enable close comparison, the NCI sample was broken down according to the same age groups and as similar as possible racial groups. Individuals were grouped by age as follows: 20–39 years, 40–59 years, and 60 years or older. Race and ethnicity were classified as non- Hispanic White, non-Hispanic Black, and His- panic/other. The first two of these race categories were identical to the comparison group from Flegal et al. Table 1 shows sample numbers by racial group, gender, and age group. Information about participant numbers by level of intellectual disability and living arrangements is shown in the results section.
Results
Overweight and Obesity Raw data were gathered on height in feet and
inches and weight in pounds, not in metric units, because these were the standard units reported in the individuals’ health records. These data were used to calculate BMI using the following formula:
BMI~ body mass lbð Þx 703
height ftð Þð Þ2 :
BMI was classified as follows: (a) underweight: BMI , 18.50; (b) normal weight: BMI 5 18.50–24.99; (c)
overweight: BMI 5 25.00–29.99; (d) obese: BMI 5 $30.00; Grade 2 obesity: BMI $ 35.00; Grade 3 obesity: BMI $ 40.00 (World Health Organization [WHO] Expert Committee on Physical Status, 1995).
Comparison with the general population. We calculated the prevalence of overweight and obesity by race, age group, and gender (Table 2). We used Flegal et al.’s (2010, Table 2) analysis of NHANES data as the basis for comparison be- tween persons with intellectual disability (Table 2) and the general population (for those $ 20 years old). Nonoverlap of the 95% confidence intervals between groups was considered to be a significant difference. To assist with comparison, selected groupings of Flegal et al.’s data (all people, all men, all women) are reproduced in Table 2 along with the corresponding groupings for people with intellectual disability drawn from the NCI sample. Readers should consult Flegal et al.’s Table 2 directly for more detailed comparisons for specific age and gender groups. Because the Hispanic and Mexican American samples were constituted differently in the general population data (Flegal et al.) than in the NCI data, we present the data for the Hispanic/other group without a general population comparison.
On most comparisons, our sample of adult service users with intellectual disability from 20 states did not differ from the nationally represen- tative sample of the U.S. population. Of 27 possible comparisons for obesity prevalence, only 4 were significant (denoted in Table 2 by an asterisk to indicate that the NCI subgroup mean differed significantly from the corresponding subgroup mean in Flegal et al.’s, 2010, Table 2).
Table 1. Number of Sample Members with Intellectual Disability by Racial Group, Gender, and Age
Gender/age group
Total
(N 5 8,911)
Non-Hispanic White
(n 5 6,488)
Non-Hispanic Black
(n 5 1,706)
Hispanic/other
(n 5 717)
Men
20–39 2,152 1,394 499 259
40–59 2,248 1,665 444 139
60+ 605 496 78 31 All men 5,005 3,555 1,021 429
Women
20–39 1,553 1,095 305 153
40–59 1,751 1,319 329 103
60+ 602 519 51 32 All women 3,906 2,933 685 288
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In each case, the group with intellectual disability had lower prevalence of obesity.
For the overweight and obesity prevalence data (lower half of Table 2), 15 of 27 (56%) comparisons were significant. Here too, the group with intellec- tual disability had lower prevalence in every case. Ten of the 12 (83%) comparisons involving men were significant, suggesting a lower prevalence of overweight and obesity among men with intellec- tual disability than men in the general U.S. population. By contrast, only 2 of the 12 (17%) comparisons for women were significant, suggest- ing that, for women, there is a similar prevalence of overweight and obesity to the general population.
Gender comparisons. Among the sample of people with intellectual disability, men were significantly less obese than women (significant pairwise gender comparisons denoted in Table 2 by means with different lowercase superscript letters when comparing the equivalent male and female subgroup within columns). This was true for the sample overall (all men vs. all women) and for non-Hispanic White and non-Hispanic Black men but not for men in the Hispanic/other group. These significant gender differences in obesity prevalence were also true for within-race compar- isons between men and women in the 20–39-year- old and 40–59-year-old age groups for White and Black participants. The absence of significant gender differences for the 60+ age group may have been due, in part, to its much smaller sample size.
Among adults with intellectual disability, gender differences were less evident for the combined overweight and obesity groups. There was a significantly lower prevalence of overweight and obesity when comparing all men (60.5%) with all women (64.5%), as well as for all Black men with all Black women, and for all men and Black men among the 20–39-year-old age group. These differences appear to have been driven by the higher obesity prevalence in women. Indeed, taking overweight (25.0 # BMI , 30.0) prevalence only, 31.0% of all men and 25.6% of all women were overweight.
Comparisons by race–ethnic group. There were no significant differences by race–ethnic group in the prevalence of obesity or of combined overweight and obesity among the sample as a whole or among men with intellectual disability. However, signifi- cantly more Black women were obese than White women (significant race–ethnic group comparisons denoted in Table 2 by means with different upper- case superscript letters within rows). When brokenT
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R 7 2 .5
(6 7 .4
– 7 7
.5 )l
S 6 4 .1
(5 6 .4
– 7 1 .7
)m R
S
N C
I: 4 0 – 5 9
6 5 .5
(6 3 .2
– 6
7 .7
)h 6 5 .2
(6 2 .6
– 6 7
.8 )j
T 6 6 .0
(6 0 .8
– 7 1
.1 )*
k T
6 7 .0
(5 7 .8
– 7 6 .2
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N C
I: 6 0
+ 6 3 .5
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– 6
7 .3
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– 6 5 .2
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N ot
e. N
C I
5 N
at io
n al
C o
re In
d ic
at o
rs . T
h e
ge n
er al
p o
p u
la ti
o n
co m
p ar
is o
n d
at a
ar e
fr o
m th
e N
at io
n al
H ea
lt h
an d
N u
tr it
io n
E xa
m in
at io
n S u
rv ey
(N H
A N
E S ;
F le
ga l et
al .,
2 0 1 0 ).
F o
r th
e H
is p
an ic
/o th
er co
lu m
n d
at a,
co m
p ar
is o
n w
it h
F le
ga l
et al
. (2
0 1 0 )
w as
n o
t p
o ss
ib le
b ec
au se
o f
d if
fe re
n t
et h
n ic
gr o
u p
in gs
u se
d in
th is
co lu
m n
. *T
h er
e w
as n
o o
v er
la p
in 9 5 %
co n
fi d
en ce
in te
rv al
s b
et w
ee n
N C
I d
at a
an d
th e
eq u
iv al
en t
N H
A N
E S
su b
gr o
u p
in F le
ga l et
al .’ s
(2 0 1 0 )
T ab
le 2 . In
al l ca
se s
o f
d if
fe re
n ce
s (n
o o
v er
la p
), N
C I
m ea
n s
w er
e lo
w er
. a – m G
en d
er co
m p
ar is
o n
s (p
ai rw
is e,
w it
h in
co lu
m n
s) :
M ea
n s
th at
sh ar
e th
e sa
m e
lo w
er ca
se su
p er
sc ri
p t
le tt
er d
id n
o t
d if
fe r
si gn
if ic
an tl
y .
A – U R
ac e–
et h
n ic
gr o
u p
co m
p ar
is o
n s
(w it
h in
ro w
s) :
M ea
n s
th at
sh ar
e th
e sa
m e
u p
p er
ca se
su p
er sc
ri p
t le
tt er
d id
n o
t d
if fe
r si
gn if
ic an
tl y .
VOLUME 116, NUMBER 6: 401–418 | NOVEMBER 2011 AJIDD
Obesity among adults R. J. Stancliffe et al.
E American Association on Intellectual and Developmental Disabilities 407
down further by age group, this Black–White racial difference was significant for women in the 20–29- year-old age group but not for either of the older age groups of women. Women in the Hispanic/ other group did not differ in obesity prevalence from women in any other racial group. The findings for overweight and obesity prevalence among women were similar.
Grade 3 Obesity Table 3 shows the prevalence of Grade 3
obesity (morbid obesity). Overall prevalence of Grade 3 obesity (BMI $ 40.0) among the NCI sample was 7.6% and ranged from 2.6% for older (60+) Black men to an exceptionally high 16.1% among younger (20–39) Black women.
Comparison with the general population. For Grade 3 obesity, 6 of 27 (22%) comparisons between the NCI sample with intellectual disabil- ity and the general population (Flegal et al., 2010, Table 3) yielded significant differences (denoted by an asterisk). In all cases, sample members with intellectual disability had significantly higher prevalence rates. Even though the overall preva- lence of obesity among adults with intellectual disability did not differ from the general popula- tion (Table 2), for Grade 3 obesity, significantly more people with intellectual disability were affected, especially younger women.
Gender comparisons. Women with intellectual disability had significantly higher prevalence of Grade 3 obesity compared with men. This was true for the overall NCI sample, for non-Hispanic White individuals and non-Hispanic Black indi- viduals (pairwise gender comparisons within columns denoted by lowercase-letter superscripts). There were no significant differences by race– ethnic group.
Diagnosis and BMI We partitioned our sample into four mutually
exclusive diagnostic groups: (a) intellectual dis- abilities only (but no Down syndrome, autism– pervasive developmental disorders, or cerebral palsy), (b) intellectual disability and Down syndrome, (c) intellectual disability and autism– pervasive developmental disorder, and (d) intel- lectual disability and cerebral palsy. Individuals with more than one diagnosis (of Down syn- drome, autism–pervasive developmental disorder, or cerebral palsy) were excluded, as were those with missing data on diagnoses (n 5 643). In
addition, because of a very small sample size, we excluded 28 individuals with Prader-Willi syn- drome, leaving a final sample of 8,272 individuals. Table 4 shows BMI data by diagnostic group.
The mean BMI for participants with Down syndrome was in the obese range ($30.0); for those with intellectual disability only or autism– pervasive developmental disorders, the mean was in the overweight range (BMI 5 25.0–30.0). Only the mean for the group with cerebral palsy was in the healthy weight range (BMI 5 18.5–24.99).
One-way analysis of variance (ANOVA) re- vealed a significant between-diagnostic-group difference, F(3, 8268) 5 116.38, p , .001. The as- sumption of homogeneity of variance was violated, so we used Tamahane’s T2 procedure to test pairwise differences among each diagnostic group. All these comparisons were significant at .001 or better, showing that BMI for individuals with Down syndrome was significantly higher than the other three groups, whereas those with cerebral palsy had significantly lower mean BMI than the other three groups. The intellectual disability–only and autism–pervasive developmental disorder groups each fell in between, but each also differed significantly from all other groups.
The mean BMI for the 28 individuals with Prader-Willi syndrome excluded from these anal- yses was 34.32 (95% confidence interval 5 30.31– 38.33), higher than for any of the four groups shown in Table 4. However, the very small sample size and consequent wide confidence intervals made between-group comparisons potentially misleading, given the likelihood of the difference from the sample with Prader-Willi syndrome not being statistically significant when a real differ- ence existed (Type II error).
Next, we examined the prevalence of com- bined overweight and obesity for the four diagnostic groups listed in Table 4. The sample size for some diagnostic groups was relatively small, so we broke down these prevalence data by gender but not by age group to limit the potential for Type II error (Table 5).
The group with cerebral palsy had a notably lower prevalence of obesity and overweight than any of the other diagnostic groups and lower than the general population (see Table 2 for general population prevalence). As Table 5 shows, for each diagnostic group as a whole (‘‘NCI all’’), the prevalence of obesity differed significantly (up- percase superscripts within rows), from a low of 17.2% (cerebral palsy) to a high of 44.3% (Down
VOLUME 116, NUMBER 6: 401–418 | NOVEMBER 2011 AJIDD
Obesity among adults R. J. Stancliffe et al.
408 E American Association on Intellectual and Developmental Disabilities
T a b
le 3 .
P re
v al
en ce
o f
G ra
d e
3 (M
o rb
id )
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es it
y A
m o
n g
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s W
it h
In te
ll ec
tu al
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ab il it
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d a
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m p
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p le
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m th
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.S .
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er al
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p u
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b y
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e, A
ge ,
an d
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d er
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5 %
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te rv
a l)
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ty :
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N ot
e. N
C I
5 N
at io
n al
C o
re In
d ic
at o
rs . T
h e
ge n
er al
p o
p u
la ti
o n
co m
p ar
is o
n d
at a
ar e
fr o
m th
e N
at io
n al
H ea
lt h
an d
N u
tr it
io n
E xa
m in
at io
n S u
rv ey
(N H
A N
E S ; F le
ga l et
al .,
2 0 1 0 ).
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e H
is p
an ic
/o th
er co
lu m
n ,
co m
p ar
is o
n w
it h
F le
ga l
et al
. (2
0 1 0 )
w as
n o
t p
o ss
ib le
b ec
au se
o f
d if
fe re
n t
et h
n ic
gr o
u p
in gs
u se
d in
th is
co lu
m n
. * T
h er
e w
as n
o o
v er
la p
in 9 5 %
co n
fi d
en ce
in te
rv al
s b
et w
ee n
N C
I d
at a
an d
th e
eq u
iv al
en t
N H
A N
E S
su b
gr o
u p
in F le
ga l et
al . (2
0 1 0 , T
ab le
3 ).
In al
l ca
se s
o f
d if
fe re
n ce
s (n
o o
v er
la p
) N
C I
m ea
n s
w er
e h
ig h
er .
a – g G
en d
er co
m p
ar is
o n
s (p
ai rw
is e,
w it
h in
co lu
m n
s) :
M ea
n s
th at
sh ar
e th
e sa
m e
lo w
er ca
se su
p er
sc ri
p t
le tt
er d
id n
o t
d if
fe r
si gn
if ic
an tl
y .
A – I R
ac e–
et h
n ic
gr o
u p
co m
p ar
is o
n s
(w it
h in
ro w
s) :
M ea
n s
th at
sh ar
e th
e sa
m e
u p
p er
ca se
su p
er sc
ri p
t le
tt er
d id
n o
t d
if fe
r si
gn if
ic an
tl y .
VOLUME 116, NUMBER 6: 401–418 | NOVEMBER 2011 AJIDD
Obesity among adults R. J. Stancliffe et al.
E American Association on Intellectual and Developmental Disabilities 409
syndrome). This is consistent with the BMI analyses shown in Table 4. Overall, significantly more women (38.4%) were obese than men (28.8%). This gender difference in obesity was repeated for the intellectual disability–only and cerebral palsy groups but did not attain signifi- cance for the smaller Down syndrome and autism–pervasive developmental disorder groups (lowercase superscripts within columns). A similar pattern of significant differences was evident for the combined overweight and obesity prevalence data shown in the lower section of Table 5.
Level of Intellectual Disability There were large and significant differences in
obesity prevalence by level of intellectual disabil- ity (Table 6). The lowest prevalence of obesity was among individuals with profound intellectual disability (12.6%). This rate was significantly and substantially lower than those with severe intel- lectual disability (26.7%), who in turn had a significantly lower prevalence rate than people with mild or moderate intellectual disability (41.4% and 38.2%, respectively). The differences between the groups of persons with mild and moderate intellectual disability were not statisti- cally significant (uppercase superscripts within rows). The gender differences noted in Table 2 are also evident in Table 6. It is notable that women had a significantly higher prevalence of obesity than men within the mild, moderate, and severe intellectual disability groups (lowercase super- scripts within columns). That is, gender differenc- es in obesity were evident at all levels except profound intellectual disability. The effects of level of intellectual disability and gender com- bined were marked; for example, almost half
(46.5%) of women with mild intellectual disability had a BMI in the obese range.
Living Arrangements Prevalence of overweight and obesity by
living arrangement and by level of intellectual disability is shown in Table 7. The last (‘‘Total’’) column of Table 7 shows the significant overall differences between living arrangements in the prevalence of obesity, with the highest prevalence among individuals living in their own home (42.8%) and the lowest among institutional residents (18.6%). Inspection of the confidence intervals in the final column of Table 7 (upper half) reveals that institutional residents had a significantly lower prevalence of obesity than any of the other residence types listed (lowercase superscripts with columns). Both host–foster home and group home had significantly lower prevalence than agency apartment, own home, and family home. Family home was significantly lower than own home, and own home and agency apartment did not differ. The comparisons for overweight and obesity (lower half of Table 7) were generally similar to the pattern for obesity.
At first glance, these univariate comparisons suggest significant variations in the prevalence of obesity among different living arrangements. However, there were substantial disparities among different living arrangements in the percentages of people at each level of intellectual disability. For example, people with profound intellectual dis- ability made up 45.2% of institutional residents but only 5.6% of agency apartment residents and only 7.4% of those living in their own home. To make these differences explicit, Table 7 also shows the total number of sample members at
Table 4. Body Mass Index (BMI) for Persons With Intellectual Disability by Diagnostic Group
Diagnostic group n M SD 95% CI
Intellectual disability only 5,723 28.55a 7.62 28.35–28.75
Intellectual disability and
Down syndrome 721 30.40 b
7.66 29.84–30.96
Intellectual disability and
autism/pervasive
developmental disability 721 27.42 c
7.16 26.90–27.95
Intellectual disability and
cerebral palsy 1,107 24.53 d
6.62 24.14–24.92
Total intellectual disability 8,272 28.07 7.61 27.91–28.24
Note. CI 5 confidence interval. a–dDiagnostic group comparisons (within columns): Means that share the same lowercase superscript letter did not differ significantly.
VOLUME 116, NUMBER 6: 401–418 | NOVEMBER 2011 AJIDD
Obesity among adults R. J. Stancliffe et al.
410 E American Association on Intellectual and Developmental Disabilities
each level of intellectual disability in each residence type. For example, there were 159 people with mild intellectual disability living in institutions, 31.4% of whom were obese. As has been shown (Table 6), there are important differences in prevalence of obesity by level of intellectual disability. This factor needs to be considered carefully when examining differences in prevalence of obesity among residence types.
When comparisons of prevalence of obesity are made among residence types within each level of intellectual disability, the differences are much less stark than they appear in the final column of Table 7. For individuals with mild intellectual disability, institutional residents still had the lowest prevalence of obesity, but the difference was only significant when compared with agency apartment and own-home residents (lowercase superscripts within columns). Signifi- cantly fewer group home and family home residents were obese than those living in their own home. There were no other significant differ- ences by residence type among sample mem- bers with mild intellectual disability. Comparison with the final column of Table 7 reveals that although differences in obesity prevalence remain, the differences among living arrangements are much smaller within each level of intellectual disability.
Likewise, in the group with moderate intel- lectual disability, significantly fewer institutional, group home, and host–foster home residents were obese than those living in their own home or family home. For those with severe intellectual disability, there were no significant differences in prevalence of obesity by living arrangement. In the case of people with profound disability, signifi- cantly fewer institution residents were obese than people from agency apartments or from family homes. There were no other significant differences by living arrangement among individuals with profound intellectual disability. Overall, the effect of living arrangement appeared to be more significant among those with moderate and mild intellectual disability and less evident among individuals with more severe intellectual disability. Across living arrangements, for individuals with mild or moderate intellectual disability, the pattern appeared to reflect lower prevalence of obesity in regulated congregate settings such as institutions but higher prevalence in more individualized, less supervised environments such as one’s own home.T
a b
le 5 .
P er
ce n
ta ge
o f
O b
es e
an d
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w ei
gh t
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u lt
s W
it h
In te
ll ec
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ab il it
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b y
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gn o
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g n
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p
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ly (n
5 5 ,6
2 7 )
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w n
sy n
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m e
(n 5
7 0 6 )
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ti sm
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: B
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d ic
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en d
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ai rw
is e,
w it
h in
co lu
m n
s) :
M ea
n s
th at
sh ar
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se su
p er
sc ri
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le tt
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id n
o t
d if
fe r
si gn
if ic
an tl
y .
A – U D
ia gn
o st
ic gr
o u
p co
m p
ar is
o n
s (w
it h
in ro
w s)
: M
ea n
s th
at sh
ar e
th e
sa m
e u
p p
er ca
se su
p er
sc ri
p t
le tt
er d
id n
o t
d if
fe r
si gn
if ic
an tl
y .
VOLUME 116, NUMBER 6: 401–418 | NOVEMBER 2011 AJIDD
Obesity among adults R. J. Stancliffe et al.
E American Association on Intellectual and Developmental Disabilities 411
Within each type of living arrangement there was a consistent pattern of differences by level of intellectual disability. The groups with mild and moderate intellectual disability did not differ on obesity prevalence within any of the six types of living arrangement listed in Table 7 (uppercase superscripts within rows). However, within every type of living arrangement, either or both groups with severe and profound intellectual disability had significantly lower prevalence rates of obesity than either or both the groups with mild or moderate intellectual disability. These findings are fully consistent with the overall results for level of intellectual disability reported in Table 6.
Discussion
We found high levels of obesity and over- weight in our 2008–2009 20-state sample of adult service users (20 years and older) with intellectual disability. Almost two thirds (62.2%) of sample members were overweight or obese (BMI $ 25.0) and one third (33.6%) obese (BMI $ 30.0). The prevalence of Grade 3 (morbid) obesity (BMI $ 40.0) was 7.6%, and was especially pronounced among younger women with intellectual disability.
Compared with a 2007–2008 nationally representative sample of the general adult (20 years and older) population (Flegal et al., 2010), adults with intellectual disability in the NCI sample had a similar or slightly lower prevalence of over- weight and obesity. Where group differences were evident, the data showed that people with intellectual disability had lower prevalence of overweight and obesity. There were few differenc- es regarding obesity, but there was a mostly consistent pattern of lower prevalence of over- weight and obesity among men with intellectual disability. There were few differences between women from the general population and women with intellectual disability.
In summary, overweight and obesity are serious health issues for American adults with and without intellectual disability, but, contrary to some previous research, prevalence is not higher among adults with intellectual disability who use intellectual disability/developmental disability ser- vices, than for the general population. Our findings differ from Yamaki (2005), whose U.S. data were derived from the NHIS, a population-based household survey. The different sample frames of the two studies may have contributed to the different findings. Our participants included manyT
a b
le 6 .
P er
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te ll ec
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ab il it
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% )
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si gn
if ic
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y .
VOLUME 116, NUMBER 6: 401–418 | NOVEMBER 2011 AJIDD
Obesity among adults R. J. Stancliffe et al.
412 E American Association on Intellectual and Developmental Disabilities
T a b
le 7 .
T o
ta l
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C I
5 N
at io
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C o
re In
d ic
at o
rs . P ar
ti ci
p an
ts w
h o
se le
v el
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in te
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tu al
d is
ab il it
y w
as u
n k n
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n o
r m
is si
n g
(n 5
4 6 2 ) w
er e
ex cl
u d
ed . R
es id
en ts
o f
n u
rs in
g fa
ci li ti
es (n
5 4 2 ),
‘‘ o
th er
’’ (n
5 1 0 8 )
re si
d en
ce ty
p es
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r w
h er
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en ce
ty p
e w
as u
n k n
o w
n o
r m
is si
n g
(n 5
7 9 )
w er
e ex
cl u
d ed
d u
e to
m is
si n
g d
at a,
sm al
l sa
m p
le si
ze ,
an d
/o r
u n
k n
o w
n re
si d
en ce
ty p
e. T
h is
y ie
ld ed
a fi
n al
sa m
p le
o f
8 ,2
3 3
b ec
au se
a sm
al l n
u m
b er
o f
p ar
ti ci
p an
ts (n
5 1 3 )
w er
e ex
cl u
d ed
o n
m o
re th
an o
n e
o f
th es
e gr
o u
n d
s. a – v L
iv in
g ar
ra n
ge m
en t
ty p
e co
m p
ar is
o n
s (w
it h
in co
lu m
n s)
: M
ea n
s th
at sh
ar e
th e
sa m
e lo
w er
ca se
su p
er sc
ri p
t le
tt er
d id
n o
t d
if fe
r si
gn if
ic an
tl y .
A – Q L
ev el
o f
in te
ll ec
tu al
d is
ab il it
y gr
o u
p co
m p
ar is
o n
s (w
it h
in ro
w s)
: M
ea n
s th
at sh
ar e
th e
sa m
e u
p p
er ca
se su
p er
sc ri
p t
le tt
er d
id n
o t
d if
fe r
si gn
if ic
an tl
y .
T h
es e
co m
p ar
is o
n s
ar e
o n
ly sh
o w
n fo
r o
b es
it y
d at
a (u
p p
er h
al f
o f
ta b
le ).
VOLUME 116, NUMBER 6: 401–418 | NOVEMBER 2011 AJIDD
Obesity among adults R. J. Stancliffe et al.
E American Association on Intellectual and Developmental Disabilities 413
adults living in formal service settings (55.8%), but the NHIS excluded most such settings. Even so, Yamaki reported an overall prevalence of obesity among adults with intellectual disability (34.6%) that was very similar to our study (33.6%). The different conclusion from Yamaki regarding the higher prevalence of obesity among persons with intellectual disability derived from a notably lower estimated prevalence of obesity in the general population (20.6%) obtained from the 1997–2000 NHIS compared with the 33.8% prevalence estimated in the 2007–2008 NHANES (Flegal et al., 2010). Indeed, an analysis of the NHANES conducted at approximately the same time as the Yamaki analysis (1999–2000) by Flegal et al. (2002) reported prevalence of obesity in the general U.S. population of 30.5% (9.9% higher than the NHIS estimate). This variation draws attention to impor- tant methodological differences.
There are important sampling differences between our study and Yamaki’s (2005), whose NHIS sample was based on a nationally represen- tative sample of households that generally exclud- ed service settings, from small group homes to institutions. Yamaki’s sample, therefore, likely included adults with milder levels of intellectual disability (the NHIS does not include data on level of intellectual disability) and fewer comorbid physical, health, and mental health conditions. Our sample, in contrast, consisted of users of intellectual disability/developmental disability services, more than half of whom were in formal residential service settings. Specifically, in our data, only the 28.2% of individuals living with family members and 13.9% living in homes they owned or rented (own home) would have been systematically included in NHIS sample.
Another important variation in methodology is that the NHIS was a self-report survey, whereas NHANES conducted direct measurements of height and weight. The differences between esti- mates of obesity in the general population by the NHIS and by the NHANES methodologies may have derived in part from tendencies for individuals to underreport their own weight (Elgar, Roberts, Tudor-Smith, & Moore, 2005; Flegal et al., 2010).
There were several notable similarities be- tween our findings and those of Yamaki (2005). Both studies noted obesity in about one third of their samples of persons with intellectual disabil- ity. Both studies reported higher prevalence of obesity among women with intellectual disability. Yamaki reported no significant difference between
adults with and without intellectual disability in the prevalence of overweight (25.0 # BMI , 30.0) and we found no difference from the general U.S. population in the prevalence of obesity.
Our conclusions are likewise both consistent with and contrary to Melville et al.’s (2008) study of obesity among adults with intellectual disability in Scotland. Melville et al.’s sample, stratified by level of intellectual disability (mild 5 44%, moderate 5 23%, severe 5 17%, and profound 5 16%) was similar to our NCI sample, as were the percentages of obesity among Scottish youth and adults (16 years and older) with intellectual disability (32.9% overall, 27.8% of men, 39.3% of women) compared to the prevalence estimates reported here (33.6%, 29.4%, and 38.9%, respectively). However, relative to the U.S. general population, there was notably lower prevalence of obesity in the general population of Scottish men (22.7%) and women (25.1%), so Melville et al. concluded that there was a higher level of obesity among persons with intellectual disability relative to the general population in Scotland.
Gender We found a consistently and significantly
higher level of obesity among women with intellectual disability than for men with intellectual disability. This was true within most racial groups, within most levels of intellectual disability, and among adults with cerebral palsy. Likewise, there was a significantly higher prevalence of Grade 3 obesity among women with intellectual disability compared with men with intellectual disability.
Melville et al. (2007, 2008) noted that in Scotland there was a greater differential in obesity rates between men and women with intellectual disability than between men and women in the general population. This held true for our data, where there was a 9.5% difference in obesity between men with intellectual disability (29.4%) and women with intellectual disability (38.9%) compared with Flegal et al.’s (2010) general U.S. population data, which showed a 3.3% difference between men (32.2%) and women (35.5%). Similarly large gender disparities in obesity prevalence among adults with intellectual disabil- ity have been reported by other researchers in the United States (Yamaki, 2005), the United King- dom (Emerson, 2005; Melville et al., 2007, 2008; Robertson et al., 2000), and Norway (Hove, 2004). The cause of this more marked gender dif- ference in prevalence of obesity is unclear, but
VOLUME 116, NUMBER 6: 401–418 | NOVEMBER 2011 AJIDD
Obesity among adults R. J. Stancliffe et al.
414 E American Association on Intellectual and Developmental Disabilities
this consistently reported phenomenon deserves attention.
Diagnosis We found that adults with Down syndrome
had the highest prevalence of obesity and individuals with cerebral palsy had the lowest. This suggests that there are diagnosis-specific issues that need to be considered when supporting individuals with different diagnoses to achieve a healthy weight. It also suggests that future research on weight and BMI within people with intellectual disability should control for diagnosis.
Level of Intellectual Disability There were consistent differences by level of
intellectual disability in prevalence of obesity. Individuals with mild (41.4%) or moderate (38.2%) intellectual disability had the highest prevalence, whereas obesity prevalence was signif- icantly lower for individuals with severe (26.7%), and profound intellectual disability (12.6%). These findings are consistent with several other studies (Emerson, 2005; Melville et al., 2008; Robertson et al., 2000) that have reported that the risk of overweight and obesity is lower as level of intellectual disability becomes more severe. The very large differences we observed by level of intellectual disability show clearly why sampling issues represent such a strong influence on reported prevalence rates of obesity among adults with intellectual disability.
What then are the likely causes of the consistent finding that obesity is related to level of intellectual disability? One factor is the much more frequent placement of adults with severe and profound intellectual disability in more highly structured and staffed residence types, such as institutions, where there is much greater staff control of residents’ food intake. More individual- ized, less regulated settings, such as living in one’s own home are characterised by greater freedom of choice for residents (Lakin et al., 2008). Likewise, individuals with milder intellectual disability exercise more everyday choice than their counter- parts with more severe intellectual disability (Lakin et al., 2008). Some authors have suggested that greater choice may be associated with unhealthy food choices and/or opting not to participate in sufficient physical activity (Rimmer & Yamaki, 2006). Bhaumic et al. (2008) found that the ability to feed oneself and to drink unaided were
independently associated with higher prevalence of obesity. Lack of independence in self-care is strongly associated with more severe intellectual disability. Last, unsupervised access to community settings (more typical for individuals with mild or moderate intellectual disability) brings with it access to fast food and other unhealthy food options. That is, a combination of personal characteristics (eating independently, choice-making skills) and environ- mental factors (living arrangements, freedom of choice, unsupervised community access) may contribute to the higher observed incidence of obesity among individuals with milder intellectual disability.
Living Arrangements Overall, our results confirmed that congregate,
regulated, continuously supervised settings such as institutions having the lowest prevalence of obesity. Such settings, often by explicit regulatory requirement, use dietary planning and controlled food intake as a formal element of the residential program. By contrast, people living in their own homes, usually with limited supervision and far fewer regulations, experienced a notably higher prevalence of obesity. Settings with intermediate levels of regulation and/or supervision (group home, host home, family home) were in between.
However, a substantial proportion of these differences was attributable to level of intellectual disability, because living arrangements differed substantially in the level of intellectual disability of their residents. For example, a much higher proportion of people living in their own home (63.9%) or agency apartments (62.9%) had mild intellectual disability than was the case for institutions (15.4%), group homes (33.5%), family homes (39.0%), or host homes (33.6%).
In addition, the effect of residence type was more pronounced for people with mild intellec- tual disability. There were numerous significant differences in prevalence of obesity among residence types for participants with mild intel- lectual disability but almost none for individuals with severe and profound intellectual disability. Perhaps individuals with mild or moderate intellectual disability have the independence to take advantage of the greater freedom offered by living in settings such as one’s own home, whereas those with more severe intellectual disability still need significant support from others to access food and drink. By contrast, institutional residents
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Obesity among adults R. J. Stancliffe et al.
E American Association on Intellectual and Developmental Disabilities 415
all have highly regulated food intake and little or no free access to food regardless of level of intellectual disability.
Conclusions The observation that adults with intellectual
disability have rates of obesity that are similar to the general population does not reduce the serious health implications of their being overweight. It seems notable that the prevalence of obesity is particularly high among persons with milder intellectual disability and places of residence that exert less control over diet and activities. In an era of increasing choice and expanded residential options, adults with intellectual disability face the same challenges as the general population: how to use choice wisely and with attention to longer term (health) implications.
Even taking level of intellectual disability into account, there remained significant differences in prevalence of obesity among different living arrange- ments, especially for those with mild and moderate intellectual disability. In general, institutional residents had the lowest prevalence of obesity and individuals living in their own home had the highest. However, we have repeatedly shown elsewhere that smaller, less regulated settings, such as living in one’s own home, are consistently associated with desirable outcomes in areas such as well being (Stancliffe et al., 2009), loneliness (Stancliffe et al., 2007), everyday choice and support-related choice (Lakin et al., 2008), as well as choice of living arrangements and living companions (Stancliffe et al., 2010), whereas institutions are associated with poorer outcomes (Lakin & Stancliffe, 2007). It is clear that a return to institutions or institution-like controls as a ‘‘solution’’ to obesity is out of the question, but supporting people with intellectual disability (and the broader U.S. popula- tion) to continue to live in their preferred settings without becoming obese is an urgent health priority.
Caveats Certain methodological differences limit the
validity of our comparisons between NCI data and Flegal et al.’s (2010) NHANES data. First, Flegal et al.’s sample was nationally representative, whereas the NCI sample came from 20 states. Second the NHANES sample was drawn from the ‘‘noninstitutionalized’’ population, whereas the NCI sample was drawn from registries of intellec- tual disability/developmental disability service users, many of whom would be viewed as
institutionalized in the NHANES methodology. Third, age was adjusted in Flegal et al.’s analyses, whereas we made no age adjustments. Fourth, as is unavoidable with representative samples of people with intellectual disability, the NCI sample had a preponderance of males (56.2%), whereas Flegal et al.’s sample contained 49.5% males. Given the observed gender differences in obesity prevalence, it is clearly important to make within-gender comparisons. Fifth, in Flegal et al.’s data, height and weight were assessed directly, whereas we used height and weight typically gathered through record review or reported by proxy respondents. Proxies, such as family members who do not have access to height and weight records, may under- estimate their family member’s weight.
Last, making large numbers of comparisons (54 comparisons in Table 2 alone) with a 95% confi- dence interval increases the Type I error rate. We adopted this approach to enable detailed compar- isons with Flegal et al.’s (2010) data, because Flegal et al. used this same analytic approach. Readers should therefore exercise caution as to the true statistical significance of individual comparisons.
Future Research Several important variables related to BMI
were not examined in the present study, such as caloric intake–nutrition and physical activity. Differences in these factors may underpin ob- served BMI differences by level of intellectual disability, diagnosis, or living arrangements; therefore, future obesity research should also examine these variables. We plan to complete a companion article looking at physical activity. Given the well-established health risks of over- weight and obesity, a fundamental priority for future studies is finding effective methods to enable adults with intellectual disability to achieve and maintain a healthy weight.
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Received 3/20/2011, accepted 6/29/2011. Editor-in-Charge: Leonard Abbeduto
Preparation of this article was supported by Grant H133G080029 for the Multi-State Data Set Project from the National Institute on Disability and Rehabilitation Research, U.S. Department of Education. Correspondence regarding this article should be sent to Roger J. Stancliffe, Faculty of Health Sciences, University of Sydney, P.O. Box 170, Lidcombe NSW 1825, Australia. E-mail: [email protected]
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Résumés en Français DOI: 10.1352/1944-7558-116.6.500
Le surplus de poids et l’obésité chez des adultes présentant une déficience intellectuelle qui utilisent des services en déficience intellectuelle dans 20 états américains
Roger J. Stancliffe, K. Charlie Lakin, Sheryl Larson, Joshua Engler, Julie Bershadsky, Sarah Taub, Jon Fortune et Renata Ticha
Les auteurs ont comparé la prévalence de l’obésité chez les participants du sondage sur les indicateurs nationaux de base et chez la popula- tion adulte générale américaine. En général, les adultes présentant une déficience intellectuelle ne différaient pas de la population adulte pour ce qui est de la prévalence de l’obésité. Pour l’obésité et le surplus de poids combinés, la prévalence était plus basse chez les hommes présentant une déficience intellectuelle que ceux de la population générale, mais était semblable chez les femmes. La prévalence de l’obésité était plus élevée chez les femmes présentant une déficience intellectuelle, les personnes avec un syndrome de Down, et les personnes présentant une déficience intellectuelle légère. La prévalence de l’obésité différait selon le lieu de résidence, les personnes habitant en institution ayant la pré- valence la plus basse et celles habitant leur propre maison présentant la plus haute. Lorsque le niveau de déficience intellectuelle était pris en compte, ces différences se trouvaient réduites, certaines demeurant toutefois significatives, par- ticulièrement pour les personnes ayant une déficience intellectuelle légère.
Un modèle des influences contextuelles sur les parents présentant une déficience intellectuelle et leurs enfants
Catherine Wade, Gwynnyth Llewellyn et Jan Matthews
Plusieurs parents présentant une déficience in- tellectuelle vivent dans des conditions pouvant
être risquées pour les enfants et les parents. Cette étude a utilisé un modèle d’équation structurelle afin de tester un modèle théorique des relations entre les parents, l’enfant, la famille et certaines variables contextuelles dans 120 familles austra- liennes à l’intérieure desquelles un parent présente une déficience intellectuelle. Les résultats révèlent que les pratiques parentales avaient un effet direct sur le bien-être des enfants, que le soutien social était associé avec le bien-être des enfants en considérant les pratiques parentales comme vari- able médiatrice et que l’accès au soutien social avait une influence directe sur les pratiques parentales. Les implications des résultats envers la recherche, l’intervention et les politiques sont explorées tout en ayant l’objectif de promouvoir un bien-être optimal pour les enfants qui sont élevés par des parents présentant une déficience intellectuelle.
Relations entre le raisonnement moral, l’empathie et les distorsions cognitives chez des hommes présentant une déficience intellectuelle et des antécédents criminels
Peter Langdon, Glynis Murphy, Isabel Clare, Tom Steverson et Emma Palmer
Quatre-vingts hommes, répartis de manière égale entre quatre groupes, ont été recrutés y compris des hommes avec et sans déficience intellectuelle. Les hommes étaient soit des criminels ou des non- délinquants. Les participants ont complété des mesures de raisonnement moral, d’empathie et de distorsions cognitives. Les résultats indiquent que les capacités de raisonnement moral des délin- quants ayant une déficience intellectuelle accu- saient un retard quant au développement, mais étaient plus matures que celles des non-délinquants présentant une déficience intellectuelle. Les délin- quants sans déficience intellectuelle avaient des capacités de raisonnement moral moins matures que les non-délinquants sans déficience intellec- tuelle. Les différences peuvent être partiellement
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