Research for Evidence Based Practice

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Collegian 28 (2021) 48–56

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Collegian

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ausal beliefs about hypertension and self-care behaviour n Korean patients

yun-E Yeom ollege of Nursing, Chungnam National University, Moonhwaro 266, Daejeon, South Korea

r t i c l e i n f o

rticle history: eceived 14 November 2017 eceived in revised form 15 April 2020 ccepted 15 April 2020

eywords: ypertension auses erception elf-care ttribution edication compliance

a b s t r a c t

Background: Hypertension is a lifelong disease that requires a healthy lifestyle and medical treatment. Patients’ views about the causes of hypertension play a role in guiding their self-care to regulate hyper- tension. Aims: This study aimed to examine the internal structure underlying the causal beliefs about hypertension in Korean patients and their influence on self-care intention and medication compliance. Methods: A cross-sectional study was conducted using a convenience sample of 145 patients. Causal beliefs about hypertension were assessed using a modified Illness Perception Questionnaire-Revised. The internal structure of causal beliefs about hypertension was extracted with an exploratory factor analysis of SPSS 22.0. The influence of causal beliefs on self-care intention and medication compliance was tested using multiple linear regression and logistic regression analyses. Findings: Causal beliefs about hypertension were structured into four dimensions: psychological, fate- related, risk, and habitual factors. Attributing the causes of hypertension to risk factors (e.g., smoking, alcohol) and fate-related factors (e.g., fate, accident) was a significant predictor of lower self-care inten- tion and poorer medication compliance, respectively. Discussion: Patients’ causal beliefs about hypertension were either relevant or irrelevant to medical facts.

Special attention is needed for patients who believe that risky behaviour or supernatural power causes hypertension. Understanding patients’ beliefs about hypertension should be highlighted as a primary step to develop nursing strategies corresponding to patients’ recognition about hypertension. Conclusion: Careful assessment of the causal beliefs about hypertension is essential to develop nursing

and

interventions to maintain

Summary of relevance Problem or Issue Although patients’ beliefs about hypertension play a role in driving self-care, little is known about Korean patients’ causal beliefs about hypertension. What is Already Known Patients’ views on the causes of hypertension have been devel- oped within a sociocultural context, but these views may not always be consistent with medical facts. What this Paper Adds Patients who attribute the causes of hypertension to risky behaviour (e.g., alcohol, smoking) or supernatural power (e.g., fate, accident) reported significantly lower self-care intention and poorer medication compliance. Careful assessment of the latent misconceptions and inadequate awareness about hyper-

tension needs to be underscored.

E-mail address: [email protected]

ttps://doi.org/10.1016/j.colegn.2020.04.007 322-7696/© 2020 Australian College of Nursing Ltd. Published by Elsevier Ltd.

promote active self-care. © 2020 Australian College of Nursing Ltd. Published by Elsevier Ltd.

1. Introduction

Hypertension is a main driver of cardiovascular diseases glob- ally (World Health Organization [WHO], 2013). The World Health Organization reported that about 31% of all global deaths in 2016 were due to cardiovascular diseases and that the annual number of deaths from cardiovascular diseases will continue to rise from 17.5 million in 2012 to 22.2 million by 2030 (WHO, 2016). According to the national statistical data of Korea, heart and cerebrovascular diseases are the second and third leading causes of death, respec- tively (Statistics Korea, 2018). Hypertension is a lifelong health problem that requires consistent self-care to reduce morbidity and mortality from cardiovascular complications (Nguyen, Dominguez, Gullapalli, & Nguyen, 2010). Empirical research has amassed substantial information about the pathophysiological features of hypertension over the last few decades, and suggested evidence-

based guidelines to help regulate hypertension (Kucukarslan, 2012; Schwingshackl, Chaimani, Hoffmann, Schwedhelm, & Boeing, 2017). However, uncontrolled hypertension and the subsequent increased prevalence of cerebro-cardiovascular diseases are still

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worldwide concern (Rahman et al., 2015;). Therefore, there is n urgent need to develop specialised intervention strategies to mprove adherence to medical regimens and active engagement in elf-care activities.

Understanding patients’ causal beliefs about hypertension is ssential to develop strategies that correspond to patients’ lay iews and cognitive need for effective management of hyperten- ion. With respect to the cause of hypertension, scientific evidence upports the connection between hypertension and genetic and nnate traits, and lifestyle choices (Liu, Li, Li, & Khan, 2017; chwingshackl et al., 2017). However, empirical research has indi- ated that approximately 95% of patients who are newly diagnosed ith primary hypertension do not have a single identifiable cause,

ut have multiple behavioural and biomedical risk factors that ake it difficult to clarify the apparent causes (Nguyen et al.,

010). It is important to identify the actual causes, but it is equally eaningful to understand how patients view the causes and,

ubsequently, how these perceptions affect self-care to help con- rol hypertension. Previous studies have warned that patients’ iews about the causes of hypertension may be related or unre- ated to scientific evidence. Some patients attribute the disease to sycho-behavioural problems (e.g., stress, unhealthy diet, seden- ary lifestyle), but others blame fate or chance (Chen, Tsai, & Lee, 009; Pickett, Allen, Franklin, & Peters, 2014). It is particularly note- orthy that both medically relevant and irrelevant beliefs about the

auses of hypertension are key factors affecting patients’ self-care nd medication management, but with personal variances within he same sociocultural context (Chen et al., 2009; Pickett et al., 014).

Empirical studies have noted potential variations in causal eliefs depending on the sociocultural context (Jessop & Rutter, 003; Kucukarslan, 2012; Schulz, Hartung, & Riva, 2013). For exam- le, patients from Western countries tend to attribute the causes of ypertension to intrapersonal factors (e.g., stress, diet, and lack of xercise), while patients from Asian countries tend to attribute the auses to not only internal traits (e.g., immunity and genetic weak- ess) but also to supernatural factors (e.g., violation of religious orals or taboos) (Schulz et al., 2013). However, the connection

etween causal beliefs and sociocultural characteristics is incon- lusive. Several studies have found similar patterns in causal beliefs cross cultures, indicating that patients generally attributed the ause of hypertension to psychological traits rather than chance or upernatural factors (Chen et al., 2009; Pickett et al., 2014). In addi- ion, a systematic review by Marshall, Wolfe, and McKevitt (2012) as not fully supported these distinguishable features based on ulture, but has found some similarities in causal beliefs between

estern and Asian patients (Marshall et al., 2012). These findings mphasise the need for a more thorough assessment to understand he unique characteristics of causal beliefs about hypertension in atients from specific sociocultural contexts.

The Illness Perception Questionnaire-Revised (IPQ-R) is appro- riate to assess an individual’s perceptual characteristics about an

llness proposed by the Leventhal’s Common Sense Model (CSM) Moss-Morris et al., 2002). The CSM postulates that an individ- al’s illness perception could function as facilitators or barriers to oping behaviours (Leventhal, Phillips, & Burns, 2016) and concep- ualised illness perception into three dimensions: cause, identify i.e., beliefs about symptoms), and seven representations including imeline (i.e., acute/chronic, cyclical), consequences, controllability i.e., personal efforts, medical treatment), coherence, and emotion.

large body of empirical research has provided strong evidence hat the IPQ-R is a useful tool to understand the characteristics of istinctive dimensions of illness perception in patients with various ealth problems such as hypertension, diabetes, and chronic kid-

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ney disease (Aberkane, 2017; Castillo, Godoy-Izquierdo, Vázquez, & Godoy, 2013). Specifically, for the dimension of causal beliefs, the internal structure of the original IPQ-R is divided into four subdi- mensions (i.e., psychological attributions, risk factors, accident or chance, and immunity) (Moss-Morris et al., 2002). Previous studies across different countries and ethnic groups have demonstrated the connections of causal beliefs to various types of health behaviours to manage hypertension (Castillo et al., 2013; Chen et al., 2009; Pickett et al., 2014).

Despite the overall usefulness of the IPQ-R, Moss-Morris et al. (2002) asserted that items could be modified for different popula- tions based on sociocultural relevance (Moss-Morris et al., 2002) since individuals form their own perceptions through life experi- ences within a specific sociocultural context (Leventhal et al., 2016). For example, Chen, Tsai, and Lee (2008) added some items to the original IPQ-R to capture the unique causal beliefs about hyper- tension in Taiwan (Chen et al., 2008). They reported two features of causal beliefs related to balance and cultural factors that were distinguished from the original IPQ-R. In addition, a comparative study on the causal beliefs in Western and Chinese cultures found that there were different patterns in the relationship between the subdimensions of causal beliefs (Lieber, Yang, & Lin, 2000). These findings support the importance of exploring the internal structure of causal beliefs by considering the unique sociocultural setting.

The Korean healthcare environment is unique in that there are multiple care options including Western medical services, tradi- tional oriental medicine, and folk remedies, all of which may affect Korean patients’ perceptions about hypertension. Prior research has demonstrated that Korean patients tend to attribute the causes of an illness to supernatural forces such as fate (i.e., unmyeong- destiny, four pillars of destiny) and disharmony with a natural power (e.g., imbalance of yin and yang) (Cha et al., 2012; Lee & Jung, 2013). In addition, a systematic review has indicated that Korean patients tend to attribute the causes of their illnesses to disharmony within the family and gender-related role burden, which reflect Koreans’ values related to familialism, Confucianism, and collectivistic cul- ture (Cha et al., 2012; Pistulka, Winch, Park, Han, & Kim, 2012; Shin, Keller, & Sim, 2018). The findings indicate that there may be Korean hypertensive patients’ causal beliefs that are different from other sociocultural settings. Thus, some items of the causal dimension in the original IPQ-R were slightly modified for this study to better reflect the unique Korean sociocultural views about health-related issues (see Appendix A Table A1). For example, the “chance or bad luck” item on the original scale was modified to “fate (e.g., misfortune, unmyeong-destiny).” In addition, the “fam- ily problems or worries” item was modified to “family conflicts and disharmony when handling a health problem.” These changes were based on empirical evidence that unsupportive interaction within a family was a causal attribution for chronic illnesses in Korean patients (Pistulka et al., 2012; Shin et al., 2018). The original item of “hereditary–it runs in my family” was omitted since this con- cept has a duplicate meaning with other items reflecting “fate” and supernatural power from the Korean Confucian perspective (Shin et al., 2018).

In sum, understanding the internal structure of causal beliefs about hypertension is an essential task to develop strategies for effective management of hypertension and the IPQ-R is a useful scale to assess the perceptual characteristics of illness perception that individuals had formed through unique experience under spe- cific sociocultural contexts. Therefore, the purposes of this study are to identify the internal structure underlying causal beliefs using a

modified IPQ-R in Korean patients with hypertension and to exam- ine the influence of causal beliefs captured from the modified IPQ-R

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n the intention to engage in self-care behaviours and medication ompliance.

. Methods

.1. Design

This is a cross-sectional study using a community-based sample f male and female patients who were medically diagnosed with ypertension in South Korea.

.2. Sample and procedure

Participants were recruited using a convenience sampling pproach from multiple sites including local clinics, cardiovascular utpatient area at a university hospital, and community centres in wo southeastern cities in South Korea. To participate in this study, otential patients had to meet the following criteria: (a) medically iagnosed with hypertension by a doctor, not self-diagnosed, (b) t least six months since being diagnosed with hypertension, (c) ithout a history of any critical episodes (e.g., stroke, heart attack)

nd complications (e.g., dialysis patients) related to hypertension n the previous six months, (d) not hospitalised for any surgery n the previous six months, (e) able to understand and respond to uestions in the questionnaire, (f) not diagnosed with psychologi- al problems or cognitive impairment by health professionals, and g) aged 18 years or older.

We contacted a total of 187 patients including 92 in the outpa- ient area of a university hospital, 72 in two local clinics, and 23 in our community centres from July 6–24, 2015. Three people were xcluded because they had not been medically diagnosed by a doc- or and 26 patients declined to participate because they had no time r interest in completing the survey. Of the initial potential partic- pants, 84.5% accepted the invitation to participate in the survey. A otal of 158 patients (79, 63, and 16 participants, respectively) from n outpatient area in a university hospital, two local clinics, and our community centers completed the self-administered surveys. hirteen questionnaires were excluded from the data analysis due o missing information in the causal beliefs dimension and finally, he data of 145 questionnaires were used for data analyses.

.3. Ethical consideration

All procedures in this study were reviewed and approved by he Institutional Review Board of the university hospital where the rincipal investigator was affiliated. Interested individuals were iven information about the rights, safety, and welfare of partic- pants involved in the study and the researchers’ responsibility to rotect the participants. Formal consent forms were obtained from ach participant who agreed to voluntarily participate in the study.

.4. Measures

.4.1. Causal beliefs The characteristics related to several dimensions of perception

bout hypertension including causal beliefs were assessed using modified IPQ-R. Although the original IPQ-R is a globally valid nstrument used to assess illness perceptions, Moss-Morris et al. 2002) who developed the original IPQ-R emphasised that an item

ay need to be modified to suit the characteristics of a particular llness or relevance to diverse sociocultural contexts (Moss-Morris t al., 2002). Therefore, some items related to the causal dimen-

ion in the original IPQ-R were slightly modified in consideration of orea’s unique views about hypertension. Also, items with a broad r general meaning were modified to identify a more specific cause. or example, the item “my own behaviour” was revised to “lack

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of physical activity” because behaviour includes multiple aspects such as diet, exercise, and social activity and because a strong link between physical activity and hypertension has been demonstrated in Korean patients (Shin et al., 2018). In addition, the original item for “stress or worries” was divided into two single items to identify the distinct psychological features since stress is considered one of the most common causes of chronic illnesses in Korean culture (Shin et al., 2018). Further, the original item “emotional status (e.g., feeling down, lonely, anxious),” which includes multiple negative feelings, was simplified to “unhappy mood” for clarification. Con- sistent with the original IPQ-R, the causal dimension of a modified IPQ-R is composed of 18 items rated on a 5-point Likert scale (1= strongly disagree, 2 = disagree, 3 = neither agree nor disagree, 4 = agree, 5 = strongly agree).

The identity dimension, which is the same as the original IPQ-R, was used to assess Koreans’ perceptions of the identity of hyperten- sion. The identity dimension is composed of 19 symptoms divided into three sections: a) symptoms that individuals had experienced recently, b) symptoms that they identified as being related to high blood pressure, and c) symptoms that they identified as being related to medications prescribed for hypertension. Each item asks for a dichotomous response (yes or no). The summed scores of the symptoms that individuals had experienced recently and that they identified as being related to high blood pressure and to medication were calculated, respectively. The number of symptoms that partic- ipants believed were related to high blood pressure were summed for the identity score in this study.

The IPQ-R also includes seven perceptual dimensions as fol- lows: The timeline-acute/chronic assesses patients’ perceptions about the duration or chronicity of their illness (i.e., hypertension). The timeline-cyclical evaluates patients’ perceptions regarding the variation of hypertension. Personal control describes patients’ perceptions about the effectiveness of personal management in curing or controlling hypertension, and treatment control assesses their expectations of the effectiveness of medical treatment or recommended advice in controlling hypertension. Consequences assesses their perceptions of the potential impact of hypertension on their personal lives, and coherence assesses the perceptions regarding their understanding of hypertension. Emotion evaluates their emotional responses to hypertension. The seven dimen- sions were assessed with 26 items rated on a 5-point Likert scale. The internal consistency in this study were as follows: Cronbach’s � = .720 (timeline-acute/chronic), � = .705 (timeline- cyclical), � = .698 (personal control), � = .737 (treatment control), � = .775 (consequences), and � = .872 (emotion).

2.4.2. Behavioural management of hypertension Self-care intention was measured with a 10-item, self-care

intention scale (Seo, 2001). The scale was developed and validated as a measurement to assess the levels of intention to engage in self-care activities that help promote health in the community- dwelling Korean population. The items on the scale asked how strongly respondents intended to engage in self-care activities such as healthy diet, physical exercise, seeking health information, and stress management on a 4-point Likert scale (1 = not at all; 2 = somewhat; 3 = moderately; 4 = very). The reliability in this study was � = .88.

Medication compliance was assessed with a single item asking how regularly in the previous three months (regularly, irregularly, no intake) the respondents had taken their prescribed medica- tions to regulate high blood pressure. Since the inclusion criteria included only patients who had been medically diagnosed and a

majority of the participants were recruited in a clinical setting, there was little possibility that patients had not been prescribed medication. In this study, we categorised patients who reported “regular intake” as “good compliance” and others (i.e., irregularly

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Table 1 Demographic characteristics (N = 145)

Variables Categories Categories

Age 57.7 ± 10.6 ≤45 19 (13.1) 46–64 99 (68.3) ≥65 27 (18.6)

Gender Male 88 (60.7) Female 57 (39.3)

Educational status ≤Elementary school 26 (17.9) Middle school 24 (16.6) High school 35 (24.1) ≥College 60 (41.4)

Marital status Married 129 (89.0) Widowed or divorced 12 (8.3) Unmarried 4 (2.7)

Living with Someone else 129 (89.0) Alone 16 (11.1)

Job Yes 96 (66.2) No 47 (32.4) Missing 2 (1.4)

Monthly allowance ≤150 55 (37.9) (10,000 won/month) 150–300 56 (38.6)

≥300 31 (21.4) Missing 3 (2.1)

Comorbidity Yes 82 (56.6) Gastrointestinal 30 (20.7) Diabetes 22 (15.1) Arthritis 18 (12.4) Liver disease 8 (5.5) Respiratory 6 (4.1)

No 63 (43.4) Years after ≤1year 32 (22.1)

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r no intake) as “bad compliance” to identify the factors affecting he patients who completely adhered to their medical treatment ompared to those who did not adhere.

.4.3. Sociodemographic and health-related information Participants completed the questionnaire including informa-

ion about their age, gender, education, income, marital status, and iving arrangements. Health-related characteristics were assessed egarding whether they had any comorbid health problems that re prevalent in Korean adult populations, such as diabetes and yperlipidemia, and how long it had been since they were medically iagnosed with hypertension.

.5. Data analysis

The data were analysed using SPSS version 22.0. Descriptive tatistics (i.e., mean, standard deviation, frequency, skewness, kur- osis, and histogram) for all variables were calculated to screen for he accuracy of data entry, missing values, outliers, normality, and omoscedasticity and to evaluate the descriptive information.

The internal structure underlying the causal beliefs about hyper- ension was extracted using a principal component analysis with

varimax rotation. The sampling adequacy of factor analysis was xamined with the value of Kaiser-Meyer-Olkin (KMO), which hould range from 0 to 1, and the Bartlett’s test of sphericity, which hould be significant (p < .05). The value of .40 or over on the fac- or loadings was chosen as the criteria for assigning an item to a articular factor. Factors with an eigenvalue greater than 1 were xtracted. The final factor of cross-loaded items was determined ased on the relevance to the logical and conceptual meaning. Inter- al consistency was evaluated by calculating Cronbach’s alpha.

The differences in causal beliefs depending on sociodemo- raphic factors and their relationships with the seven dimensions f illness perceptions about hypertension were evaluated using T- est, ANOVA, and Pearson’s correlation coefficient. The influence f causal beliefs on self-care intention and medication compliance as tested using multiple linear regression and multiple logistic

egression analyses, respectively. A post-hoc power analysis was done to verify the adequacy of

he sample size for multiple linear regression analysis using the *power program. The achieved power was .96 with the condi-

ion of the effect size (.23, medium to large) calculated by the R2

hange, type 1 error [�] criterion of .05, a total sample size of 145, nd 17 predictors for the linear multiple regression test. Therefore, he adequacy of the total size was demonstrated (Faul, Erdfelder, uchner, & Lang, 2009). In addition, DeVellis (2003) suggested that t least five samples per item are required as the criteria for an ade- uate sample size in a factor analysis (DeVellis, 2003). According to he criteria, a minimum of 90 samples for 18 items was required, onfirming that the sample size of 145 in this study was satisfactory.

. Results

.1. Descriptive information of the participants

The average age of the participants was 57.7 (SD = 10.6) with range from 32 to 90, and 68.3% of the participants were middle- ged (ages 45–64) patients. More than half of the participants were ale (60.7%) and had a job (66.2%). A majority were married and

ived with a spouse or someone else (89.0%) and most graduated igh school (24.1%) or college (41.4%).

Approximately half of the participants (56.6%) reported at least ne or more comorbid health problems, including gastrointestinal rouble (20.7%) and diabetes (15.1%). Approximately 73% of the par- icipants had been diagnosed with hypertension at least two years

hypertension diagnosis 1–5 year 53 (36.6) ≥5 year 60 (41.3)

previously and 41.3% had lived with hypertension for over five years (Table 1).

Differences were examined in demographic and health-related characteristics of the participants who were recruited from the three different settings (i.e., 71 from the outpatient area of a univer- sity hospital, 58 from local clinics, and 16 from community centers). There were no significant differences in age (F = 1.38, p = .32), gen- der (�2 = 3.61, p = .16), job status (�2 = 3.20, p = .20), education (F = 2.03, p = .13), years after hypertension diagnosis (�2 = 9.54, p = .12), and the number of chronic illnesses (F = .61, p = .54).

With regard to medication compliance, more than half of the participants (n = 95, 65.5%) reported that they had regularly taken their prescribed medication for regulating hypertension (i.e., “good compliance” group). The proportions of participants who reported irregular or no intake of their hypertension medications (i.e., “bad compliance” group) were 15.2% (n = 22) and 19.3% (n = 28), respec- tively.

The mean score of self-care intention was 3.08 (SD = .41, range = 2–4), indicating that participants tended to report a relatively stronger intention to engage in self-care activities.

3.2. Internal structure underlying the causal beliefs about hypertension

A four-factor structure underlying the causal beliefs was extracted from the exploratory factor analysis, which explained 59.3% of the total variance (see Table 2). The four structures were defined as psychological, fate-related, risk, and habitual factors. Assigning meaning to the factors is an inductive and theoreti- cal process (Henson & Roberts, 2006). Labelling each factor was

chosen based on the conceptual relevance to causal attributions noted in empirical and theoretical findings and Korean socio- cultural values. A factor that loaded with five items (i.e., worry, unhappy mood, stress, my mental attitude, and my personality)

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Table 2 Factor structure and reliability of the causal beliefs using a modified IPQ-R

Items Psychological Fate-related Risk Habitual M(SD) Reliability

Psychological Worry .766 Unhappy mood .718 Stress .710 2.59 (.83) � = .806 My mental attitude (e.g., thinking about life negatively)

.569

My personality .540 Fate-related A germ or virus .734

Pollution in the environment .697 Poor medical care in my past .688 Fate (e.g., misfortune, unmyeong-destiny)

.621 1.88 (.69) � = .762

Accident or injury .436 Poor immune system .415

Risk Smoking .811 2.63 1.03) � = .767Alcohol .804

Aging .626 Habitual Diet or eating habits .839

3.09 (.85) � = .732 Lack of physical activity .810 Family conflicts and disharmony .453

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Overwork

Variance explained (%) Total = 59.3

34.5

as labelled a psychological factor and a factor that loaded with hree items (i.e., smoking, alcohol, and ageing) was labelled a risk actor. These labels were the same as the original scale. A factor hat loaded with six items (i.e., a germ or virus, pollution in the nvironment, poor medical care in my past, fate, accident or injury, nd poor immune system) was newly named a fate-related factor ince these perceptions reflect the value of supernatural attribution e.g., Unmyeong — destiny, disharmony with a natural energy flow, mbalance between yin and yang) in Korean culture (Shin et al., 018). One of the factors labelled immunity on the original scale as not extracted as a separate domain, and the immunity item

oaded onto the fate-related factor. The factor that loaded with four tems (i.e., diet or eating habits, lack of physical activity, family con- icts and disharmony, and overwork), which were part of the risk

actors in the original scale, was named the habitual factor. The psychological factor explained 34.5% of the variance (eigen-

alue = 6.05, � = .806) followed by the fate-related factor explaining 0.4% of the variance (eigenvalue = 1.87, � = .762), risk factor xplaining 7.9% of the variance (eigenvalue = 1.43, � = .767), and abitual factor explaining 6.5% of the variance (eigenvalue = 1.18,

= .732).

.3. Factors related to causal beliefs

The mean scores of causal beliefs were as follows: 2.59 (SD = 83) for the psychological factor, 1.88 (SD = .69) for the fate-related actor, 2.63 (SD = 1.03) for the risk factor, and 3.09 (SD = .85) for the abitual factor. These findings indicated that the patients blamed abitual problems (e.g., eating and exercise habits) most strongly

or their hypertension compared to any other causes. The mean scores of illness perceptions in other dimensions were

s follows: 3.04 (SD = .77) for timeline-acute/chronic (i.e., percep- ions about the chronicity of hypertension); 2.17 (SD = .65) for imeline-cyclical (i.e., perceptions about fluctuation and unpre- ictability of hypertension); 3.21 (SD = .74) for personal control i.e., perceptions about the effectiveness of personal management n controlling hypertension); 3.52 (SD = .83) for treatment control i.e., perceptions about the effectiveness of medical treatment in ontrolling hypertension); 1.97 (SD = .62) for consequences (i.e.,

erceptions of the potential impacts of hypertension on one’s per- onal life); 3.26 (SD = .94) for coherence (i.e., perceptions regarding nderstanding of hypertension); and 2.47 (SD = .87) for the emo- ional dimension (i.e., emotional responses to hypertension). On

.407

10.4 7.9 6.5

average, participants had recently experienced 2.94 symptoms (SD = 2.91, range = 0–14). The average number of symptoms identi- fied as being related to high blood pressure in terms of the identity dimension was 2.48 (SD = 3.29, range = 0–14), and the average num- ber of symptoms identified as being medication-related was 1.20 (SD = 2.99, range = 0–9). They experienced fatigue the most fre- quently (n = 43) followed by headache (n = 37), sleep disorder (n = 31), and dizziness (n = 29). The symptoms that they believed were more likely related to high blood pressure or medications were headache (n = 29) and dizziness (n = 21) for high blood pressure and nausea (n = 17) and dizziness (n = 8) for medications.

As shown in Table 3, some dimensions of causal beliefs were significantly different based on age, gender, education, and the duration of hypertension. Attributing hypertension to a habitual factor was significantly different between age groups as well as duration of hypertension, showing that patients under 45 years of age had relatively stronger causal beliefs about the habitual fac- tor (F = 3.89, p = .020), compared to middle-aged (ages 45-64) or older patients. Those who had had hypertension for over five years also reported stronger causal beliefs about the habitual fac- tor compared to their counterparts (t = 1.96, p = .052). Attributing hypertension to a risk factor was significantly different by gender. Male patients had stronger causal beliefs about the risk factor than female patients (t = 3.34, p = .000). Attributing hypertension to a fate-related factor was significantly different by education level and living status. Patients who had low levels of education (i.e., below elementary school graduation) (t = 2.15, p = .024) and those who had lived with family members had stronger causal beliefs about the fate-related factor compared to their counterparts (t = −2.90, p = .000).

Each sub-dimension of causal beliefs was correlated with sev- eral illness perceptions with coefficient values ranging from .17 to .50 (see Table 3). The psychological dimension of causal beliefs was correlated to emotion (r = .41, p = .00), consequences (r = .33, p = .00), and personal control (r = .19, p = .01) but not to treatment con- trol (r = .13, p = .10). The fate-related dimension of causal beliefs was significantly correlated to timeline-cyclical (r = .34, p = .00) and emotion (r = .42, p = .10). The risk dimension of causal beliefs was correlated to timeline-cyclical (r = .25, p = .00), and the habitual dimension of causal beliefs was correlated to most of the illness perceptions except identity and coherence. All sub-dimensions of

causal beliefs were correlated to consequences (r = .15–.50), while none of them were correlated to identity of causal beliefs.

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Table 3 Factors related to causal beliefs of a modified IPQ-R

Variables Categories Psychological Fate-related Risk Habitual

Mean t/F/r (p)

Mean t/F/r (p)

Mean t/F/r (p)

Mean t/F/r (p)

Age 45 2.98

2.68 (.07)

1.92 0.57 (.58)

2.87 0.71 (.38)

3.59 3.89 (.02)

46–65 2.51 1.84 2.56 3.01 >65 2.57 1.98 2.61 3.03

Gender Male 2.56 −0.05

(.49) 1.81 −1.43

(.15) 2.84 3.34

(.00) 3.02 −1.34

(.45)Female 2.64 1.97 2.28 3.21

Education Low (≤elementary)

2.55 1.27 (.20)

2.21 2.15 (.02)

2.35 −0.88 (.37)

3.21 0.76 (.44)

High 2.78 1.73 2.57 3.07

Living status Alone 2.51 −0.97

(.33) 1.72 −2.90

(.00) 2.48 2.13

(.03) 3.08 −0.62

(.60)With family 2.64 2.31 2.90 3.19

Job Yes 2.64 1.19

(.23) 1.91 −0.57

(.56) 2.62 0.73

(.46) 3.17 1.42

(.53)No 2.51 1.83 2.63 3.00 Years after hypertension diagnosis

<5year 2.69 −1.39 (.16)

1.94 −1.31 (.19)

2.74 −1.53 (.12)

3.00 1.96 (.05)≥5 year 2.49 1.79 2.47 3.28

Illness Perceptions

Identity .09 (.13)

.07 (.39)

.11 (.15)

.13 (.11)

Timeline-acute/chronic .13 (.09)

.15 (.08)

−.01 (.91)

.39 (.00)

Timeline - cyclical .24 (.00)

.34 (.00)

.25 (.00)

.20 (.01)

Personal control .19 (.01)

−.08 (.32)

.14 (.10)

.39 (.00)

Treatment control .13 (.10)

.01 (.99)

.15 (.08)

.31 (.00)

Consequences .33 (.00)

.50 (.00)

.27 (.00)

.17 (.05)

Coherence .07 (.39)

−.03 (.73)

.12 (.14)

.16 (.06)

Emotion .41 (.00)

.42 (.00)

.14 (.09)

.31 (.00)

Table 4 Influence of causal beliefs on self-care intension and medication compliance

Self-care intention Medication compliancea

B ̌ t(P) Exp (B) B P

Age .002 .060 .523(.602) 1.074 .071 .028 Genderb −.050 .097 −.517(.606) 1.100 .096 .881 Education .001 .001 .011(.991) .576 −.551 .086 Years after diagnosis −.019 −.065 −.636(.526) 1.455 .375 .042 Number of illnesses −.063 −.155 −1.633(.105) .871 −.139 .618 Identity −.003 −.017 −.190(.850) 1.040 .039 .655 Timeline-acute/chronic .002 .004 .034(.973) 1.035 .035 .927 Timeline-cyclical −.009 −.013 −.138(.891) .780 −.248 .565 Personal control .071 .123 1.255(.212) 1.098 .093 .799 Treatment control .109 .207 1.933(.054) 1.222 .201 .581 Consequences −.051 −.078 −.676(.500) 3.827 1.342 .013 Coherence −.002 −.005 −.046(.964) 1.578 .456 .132 Emotion .051 .105 .890(.375) .666 −.406 .274 Cause-Psychological −.028 −.055 −.488(.627) 1.912 .648 .102 Cause-Fate-related .045 .071 .614(.540) .205 −1.586 .005 Cause-Risk −.121 −.300 −2.617(.010) .794 −.008 .558 Cause-Habitual .010 .020 .162(.872) 2.031 −.230 .085 R2 .193 .325

n pres

3 m

h s a d n p s

a Regular intake of medication prescribed = 1, Irregular or no intake of medicatio b Male = 1, Female = 0.

.4. Influence of causal beliefs on self-care intention and edication compliance

The causal beliefs about the risk factor (e.g., smoking, alco- ol) was a significant factor predicting the intent to engage in elf-care ( ̌ = −.300, p = .010) after taking into account the covari- tes including demographic and health-related factors, the seven

imensions of illness representation about hypertension, and the umber of symptoms identified as being related to high blood ressure (i.e., identity). This result indicates that patients with tronger causal beliefs about the risk factor had a lower inten-

cribed = 0.

tion to engage in self-care activities to regulate their high blood pressure.

The causal beliefs for the fate-related factor was a significant predictor of medication compliance (odds ratio = 0.205, p = .005), after taking into account the covariates. This finding indicates that patients who tended to attribute the cause of hypertension to the fate-related factor were 0.205 times less likely to comply with

their medication regimen, meaning that medication compliance decreased by as much as 79% when patients had stronger causal beliefs about the fate-related factor. Additionally, age (odds ratio = 1.074, p = .028), the duration of hypertension (odds ratio = 1.455,

5 egian 2

p 3 a h t p o m

4

c m i s K c h t h w A C d

s w r a a “ n l n a l t p b t a p c t a b p

c h t f o m c c l ( b & e w r 2 t

4 H.-E. Yeom / Coll

= .042), and the illness perception of consequences (odds ratio = .827, p = .013) were significant predictors of medication compli- nce (see Table 4). Thus, patients who were older or had lived with ypertension for a longer time were more likely to comply with heir medication regimen. Regarding the consequences dimension, atients who were more concerned about the detrimental impact f hypertension on their lives were more likely to comply with their edication regimen.

. Discussion

A solid understanding of causal beliefs is essential to capture the ore educational information needed to improve active behavioural anagement of patients with hypertension. The current study

nvestigated Korean patients’ beliefs about the causes of hyperten- ion using the IPQ-R slightly modified for better relevance to the orean sociocultural context and found that causal beliefs were lassified into four factors: psychological, fate-related, risk, and abitual factors. These factors were labeled based on the concep- ual relevance to the perceptual characteristics of Koreans with ealth problems. Although the overall features of causal beliefs ere consistent across several ethnic groups, including African- merican, Spanish, and Taiwanese populations (Castillo et al., 2013; hen et al., 2008; Pickett et al., 2014; Rahman et al., 2015), slightly istinct aspects in the Korean patients were detected.

Two factors reflecting slightly distinct aspects with the original cale were newly labelled. One is the fate-related factor that loaded ith six items (i.e., a germ or virus, pollution, pollution in the envi-

onment, poor medical care in my past, fate, accident or injury, nd poor immune system), which is comparable to the chance or ccident factor of the original scale. The äccident or chanceänd immunity” factors were identified as separate factors in the origi- al scale. However, this study found that items under these factors

oaded onto the same dimension and that they represent super- atural attributions of destiny, disharmony with a natural power, nd imbalance of yin and yang (Shin et al., 2018). Another newly abelled factor in this study was the habitual factor. It is notewor- hy that some items (i.e., diet and my own behaviour modified to hysical activity) loaded onto the risk factors in the original scale, ut in this study they had loaded onto the habitual factor along with he other items (i.e., overwork and family conflicts). The findings re consistent with prior evidence that unhealthy lifestyles, such as oor exercise, diet, and interpersonal relationships in daily life can ause hypertension (Nicoll & Henein, 2010). The findings also imply hat well-known hypertension risk factors (e.g., smoking, alcohol, nd ageing) need to be considered separately from general lifestyle ehavioural aspects. The patterns of items that loaded onto the sychological and risk factors were similar to the original scale.

It is particularly notable that the psychological factor was most ommonly identified, accounting for patients’ causal beliefs about ypertension across different countries. It is also noteworthy that he patients in this study most strongly agreed that the habitual actor reflecting an unhealthy lifestyle, such as poor eating and verwork, was a cause of hypertension. This factor was reported far ore often than for the other causal beliefs including psychologi-

al, risk, and fate-related factors. This finding is interesting in that it ontradicts the prior assumption that Asian patients may be more ikely to attribute their disease to external or supernatural factors e.g., bad luck, accidental causes, heredity) than to intrapersonal ehavioural problems (e.g., lifestyle, psychological distress) (Jessop

Rutter, 2003; Schulz et al., 2013). A study in Taiwan also offered vidence that contradicts this assumption by showing that patients

ere more likely to attribute hypertension to intrapersonal factors

elated to poor daily habits than to supernatural factors (Chen et al., 009). In contrast, a study of African-American patients reported hat they tended to blame hypertension on external factors that

8 (2021) 48–56

were beyond their control, such as bad luck and pollution, rather than intrapersonal and biomedical problems, such as stress, alcohol use, and poor medical care (Pickett et al., 2014).

The current study supports prior empirical findings that specific features of patients’ causal beliefs about hypertension (i.e., risk, fate-related factor) are meaningfully linked to sociodemographic characteristics, particularly gender and education level (Pickett et al., 2014). Consistent with the findings about African-American patients, men than women were more likely to believe that risky behaviour, such as smoking and drinking alcohol, caused hyper- tension and patients who were relatively less educated tended to believe that misfortune or accident caused their hypertension. Therefore, the findings add evidence that the diversity of causal beliefs cannot be solely attributed to a general sociocultural context, but that they are intertwined with patients’ intrapersonal characteristics, such as gender and education level. Thus, further cross-cultural studies that match patients’ sociodemographic factors across diverse countries may more successfully capture the sociocultural differences in patients’ causal beliefs about hypertension.

As a key finding, this study demonstrated that causal beliefs about risky behaviour and supernatural power could act as a barrier that impedes patients’ engagement in current or future continuous self-care behaviours, respectively. Patients who reported stronger causal beliefs about the risk factor, such as smoking and drinking alcohol, tended to express lower levels of intention to engage in self-care to manage hypertension. This finding is consistent with the study by Pickett et al. (2014) reporting that African-American patients who blamed hypertension on risky behaviours were less likely to engage in self-care behaviours, such as a healthy diet and physical activity. This result indicates the need to pay specific atten- tion to patients who are accustomed to smoking or drinking alcohol in that they may be less active in modifying their risky behaviours even when they recognise the threats.

Patients who believed that fate or supernatural power (e.g., mis- fortune, accident or injury) caused their hypertension also tended to report poor medication compliance, which is consistent with previous findings from patients in both Western and Asian coun- tries (Chen et al., 2008; Liu et al., 2017; Marshall et al., 2012; Pickett et al., 2014). The patients in this study were relatively less edu- cated in that 34.5% of the participants reported their education level as middle school graduation or lower. Although we could not conclude that formal education levels perfectly correspond to knowledge levels about hypertension, a number of empiri- cal studies have demonstrated the relationship between formal education levels and health-related information and knowledge about health conditions (Pickett et al., 2014; Rahman et al., 2015). Therefore, this finding implies that insufficient knowledge or mis- understanding about hypertension may explain why patients who blame external or supernatural factors for their hypertension are reluctant to comply with the prescribed therapeutic regimens. The findings, therefore, emphasise the need to provide stratified edu- cational information corresponding to patients’ knowledge and beliefs about hypertension.

Patients who tended to attribute the cause of hypertension to risk or fate-related factors were also more likely to believe that hypertension fluctuated or had unpredictable patterns by report- ing a higher level of perception in the timeline-cyclical dimension. This result adds evidence that patients’ recognition of expected and manageable situations about their illness, in terms of stability and predictability, may be a meaningful cognitive feature related to behavioural management of chronic illnesses including hyper-

tension (Rahman et al., 2015).

The current study underscores the importance of assessing causal beliefs about hypertension by demonstrating that inaccurate and misconceived causal beliefs about hypertension are significant

egian 2

b r b p n p u R t c e

r v m H s i n o p c s t i d t b w n t s e n w s c w

5

t h p b t e s c

t p a t b b l o b t e p t p

H.-E. Yeom / Coll

arriers that hinders a patient’s compliance with the medication egimen as well as their further intention to engage in self-care ehaviours (Claassen et al., 2011; Marshall et al., 2012). Healthcare rofessionals should play a key role in helping these patients recog- ise their own views about hypertension and to become active roblem solvers by modifying their misconceptions and insufficient nderstanding of their disease (Kang, Kim, Bae, Choi, & Shin, 2014; ahman et al., 2015). Through a process wherein patients reveal heir perceived cause of hypertension, healthcare professionals ould become supportive facilitators who encourage patients to ngage in active self-care to manage their hypertension.

Some limitations of the study need to be addressed. With espect to the methodological approach, a self-administered sur- ey may be considered a potential risk in that the participants ay have overstated their opinions due to social desirability bias. owever, using a survey is one of the most common methods

ince it is a simple, reliable, and valid way to measure beliefs n empirical research (Short et al., 2009). In addition, the conve- ience sampling approach in this study limits the interpretation f the study’s findings in terms of being generalised to all Korean atients. The causality between causal beliefs and behavioural haracteristics cannot be definitively determined due to the cross- ectional design. Another concern regarding generalisation is about he scale to assess self-care intention which was validated and lim- ted to a Korean population. Thus, a longitudinal study that targets iverse populations using a globally validated scale is warranted o build a solid foundation regarding the characteristics of causal eliefs about hypertension among the Korean population. Lastly, e assessed medication compliance by asking patients whether or ot they had regularly taken their prescribed medication. A sys- ematic review noted that patients tend to intentionally reduce or top taking medication without consulting their doctors (Marshall t al., 2012). Therefore, although all patients were medically diag- osed as hypertensive patients, it is possible that they had not met ith their health professionals to discuss whether they were con-

istent in their prescription adherence. Thus, future studies need to onsider detailed assessments of medication compliance, including hether or not a patient has been prescribed medication.

. Conclusion

This study classified Korean patients’ causal beliefs about hyper- ension into four dimensions: psychological, fate-related, risk, and abitual factors. Attributing the cause of hypertension to the sychological factor most strongly accounted for patients’ causal eliefs. This study also demonstrated that patients’ beliefs about he causes of hypertension may be consistent with or may be irrel- vant to medical facts. In addition, their causal beliefs are related to ociodemographic characteristics including age, gender, and edu- ation.

It is noteworthy that each of the causal beliefs attributing hyper- ension to the risk factor or fate-related factor was a significant redictor of patients’ intention to engage in self-care and their ctual medication compliance, respectively. The findings highlight hat special attention needs to be given to patients who have causal eliefs about supernatural power and to those who engage in risky ehaviours of smoking and alcohol consumption to explore some

atent misconceptions and inadequate awareness of the causes f hypertension. A comprehensive assessment of patients’ causal eliefs about hypertension should be highlighted to acknowledge he possible gaps between patients’ causal beliefs and scientific

vidence of the cause of hypertension. Such an assessment could rovide informational and psychological support corresponding to he patients’ cognitive needs and could subsequently affect their resent and proactive self-care behaviours.

8 (2021) 48–56 55

Ethical statement

All procedures in this study were reviewed and approved by the Dongguk University Gyeongju Hospital Institutional Review Board (reference number: DUGH-IRB-12-05, date: February 12, 2013).

Conflict of interest

None.

Funding

No financial support was received to conduct this study.

CRediT authorship contribution statement

Hyun-E Yeom: Conceptualization, Project administration, Methodology, Investigation, Data analysis, Writing - review & edit- ing.

Appendix A.

Table A1 Comparisons of the items on causal dimension between the original and modified IPQ-R

Original scale A modified scale for the study

1 Stress or worrya Stressa

2 Hereditary – it runs in my familyb

Worrya

3 A germ or virus A germ or virus 4 Diet or eating habits Diet or eating habits 5 Chance or bad luckc Fate (e.g., misfortune,

unmyeong-destiny)c

6 Poor medical care in my past Poor medical care in my past 7 Pollution in the environment Pollution in the environment 8 My own behaviourd Lack of physical activityd

9 My mental attitude (e.g., thinking about life negatively)

My mental attitude (e.g., thinking about life negatively)

10 Family problems or worriese Family conflicts and disharmony when handling a health probleme

11 Overwork Overwork 12 My emotional state (e.g.,

feeling down, lonely, anxious, empty)f

Unhappy mood (e.g., feeling down, lonely, anxious, empty) f

13 Aging Aging 14 Alcohol Alcohol 15 Smoking Smoking 16 Accident or injury Accident or injury 17 My personality My personality 18 Poor immune system Poor immune system

a,c,d,e,f A modified item; bDeleted in this study.

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