Mental Illness

Regular Article

Does improvement of cognitive functioning by cognitive remediation therapy effect work outcomes in severe mental illness? A secondary analysis of a randomized controlled trial Emi Ikebuchi, MD, PhD,1* Sayaka Sato, PhD,2 Sosei Yamaguchi, PhD,2

Michiyo Shimodaira, PhD,3 Ayano Taneda, PhD,2 Norifumi Hatsuse, MD, PhD,1

Yukako Watanabe, MD, PhD,1 Masuhiro Sakata, MD,4 Naoko Satake, MD,4

Masaaki Nishio, MD, PhD5 and Jun-ichiro Ito, MD, PhD6 1Department of Psychiatry, Teikyo University School of Medicine, 2Department of Psychiatric Rehabilitation, National Institute of Mental Health, National Center of Neurology and Psychiatry, 3Department of Mental Health/Psychiatric Nursing, Graduate School of Medicine, University of Tokyo, 4National Center of Neurology and Psychiatry, National Center Hospital, Tokyo, 5Tohoku Fukushi University School of Welfare, Sendai, 6ACT-J Team/The Clinic ‘Si Puo Fare’, Miyagi, Japan

Aim: The aim of this study was to clarify whether improvement of cognitive functioning by cognitive remediation therapy can improve work outcome in schizophrenia and other severe mental illnesses when combined with supported employment.

Methods: The subjects of this study were persons with severe mental illness diagnosed with schizo- phrenia, major depression, or bipolar disorder (ICD-10) and cognitive dysfunction who partici- pated in both cognitive remediation using the Thinking Skills for Work program and a supported employment program in a multisite, randomized controlled study. Logistic and multiple linear regression analyses were performed to clarify the influence of cognitive functioning on vocational outcomes, adjusting for demographic and clinical variables.

Results: Improvement of cognitive functioning with cognitive remediation significantly contributed to the total days employed and total earnings of com- petitive employment in supported employment service during the study period. Any baseline demo- graphic and clinical variables did not significantly contribute to the work-related outcomes.

Conclusion: A cognitive remediation program trans- ferring learning skills into the real world is useful to increase the quality of working life in supported employment services for persons with severe mental illness and cognitive dysfunction who want to work competitively.

Key words: cognitive functioning, cognitive remedi- ation, schizophrenia, supported employment, work- ing life.

S CHIZOPHRENIA PROFOUNDLY AFFECTSsocial functioning, including working life. Previ- ous studies have reported that the employment rate

of people with schizophrenia is below 20%.1,2

Nationwide data from the Israeli Psychiatric Hospitalization Case Registry reported that the per- centage of patients with only one admission who were earning minimum wage or above was 10.6% for schizophrenia compared with 24.2% for bipolar disorder in 2010, and the percentage of patients with multiple admissions was only 5.8% for schizo- phrenia.3 The competitive employment rate among

*Correspondence: Emi Ikebuchi, MD, PhD, Department of Psychiatry, Teikyo University School of Medicine, 2-11-1 Kaga, Itabashi-ku, Tokyo 186-8503, Japan. Email: pxm06766@nifty.com Received 26 August 2016; revised 19 October 2016; accepted 16 November 2016.

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schizophrenia patients within the working age using a population-based nation-wide registry system in Norway was 10.24%.4

A systematic review assessing whether achieving employment alters the course of schizophrenia- spectrum disorders reported 12 analyses represent- ing eight cohorts and 6844 participants.5 Achieving employment was consistently associated with a reduction in outpatient psychiatric treatment, as well as improved self-esteem; it was inconsistently associ- ated with symptom severity, psychiatric hospitaliza- tion, life satisfaction, and global well-being; and was consistently unrelated to worsening outcomes. Sup- ported employment has been reported to improve work outcome of persons with severe mental illness. Supported employment should adhere to evidence- based definitions of the practice: minimal prevoca- tional training and assessment, rapid job search for competitive employment in community settings, provision of follow-up support, and services based on individuals’ preferences. Eleven studies of rando- mized controlled trials of supported employment were reviewed, and outcomes strongly favored sup- ported employment groups in terms of the percent- age of participants who worked competitively at any point during the studies as compared with tradi- tional vocational service groups: 51% versus 18%, respectively.6 A meta-analytic study showed that the Individual Placement and Support model of sup- ported employment produced better competitive employment outcomes for persons with severe men- tal illness compared with alternative vocational rehabilitation regardless of background demo- graphic, clinical, and employment characteristics.7,8

Five-year follow-up of a randomized controlled trial reported that the beneficial effects of supported employment on the rate of competitive work were sustained over the 5-year follow-up period, and par- ticipants were significantly less likely to be hospitalized.9

Cognitive dysfunction in schizophrenia is well- known to influence work outcome. Giugiario et al.10

reported that verbal memory, general psychopathol- ogy, and awareness of mental illness were signifi- cantly better in employed than unemployed patients in 253 outpatients with stable schizophrenia. McGurk et al.11 researched 30 patients who were newly enrolled in a supported employment program and found that patients with severe cognitive impairment required greater amounts of services to maintain employment.

Cognitive remediation has been shown to improve cognitive functioning of schizophrenia.12

Therefore, cognitive remediation is focused on as a supporting program of supported employment that improves vocational outcomes.13 Seventy-two patients with schizophrenia or schizoaffective disor- der participated in a hybrid transitional and sup- ported employment program, and were randomly assigned to a Neurocognitive Enhancement Therapy group, or a vocational program only group.14 Neu- rocognitive Enhancement Therapy patients worked significantly more hours during the 12-month follow-up period. McGurk et al.15 reported that par- ticipants in an enhanced supported employment program with cognitive remediation using the Thinking Skills for Work program showed more improvement than the enhanced supported employ- ment only patients on measures of cognitive func- tioning, and consistently better competitive employment outcomes during the follow-up period. Sato et al.16 reported that schizophrenia patients in a supported employment program with a Japanese version of the Thinking Skills for Work program showed greater improvement in cognitive function- ing than patients in a traditional vocational service only. However, few studies have examined the asso- ciation between cognitive improvement produced by cognitive remediation and vocational outcomes. The aim of this study was to clarify whether

improvement of cognitive functioning by cognitive remediation therapy can improve work-related out- come of schizophrenia and other severe mental ill- nesses when combined with supported employment. This research may support the validity of a combination of cognitive remediation with a supported employment program, which will be ben- eficial for both clients and service providers if improvement of cognitive functioning favors work- related outcomes.

METHODS

Subjects

The inclusion criteria for study participants in the randomized controlled trial (RCT; Sato et al., in preparation) were as follows: (i) hospital outpati- ents at one of the six sites; (ii) age: 20–45 years; (iii) diagnosis: schizophrenia, major depression, or bipolar disorder (ICD-10); (iv) cognitive dysfunc- tion, with scores on the Verbal Fluency or Coding

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302 E. Ikebuchi et al. Psychiatry and Clinical Neurosciences 2017; 71: 301–308

subscales of the Japanese version of the Brief Assess- ment of Cognition in Schizophrenia16,17 (BACS) of at least −0.5 SD below the average score of a healthy population; and (v) unemployment. The potential participants were given a full explanation of the study and the ethical issues, and written informed consent was gained from all subjects. The subjects of this study were only persons who participated in both cognitive remediation and the supported employment program in the randomized controlled study described below.

Study design and main results of the RCT

We conducted an individual-level RCT at six sites in Japan (randomization and recruitment procedures are described in detail elsewhere; Yamaguchi et al.,17

and Sato et al., in preparation). The RCT had two groups (cognitive remediation [CR] + supported employment [SE] group vs traditional vocational services [TVS] group). In this study, only CR + SE group data were used because the aim of this study was to verify the synergistic effects of CR + SE (the TVS group in the RCT was not included in this study). Outcome assessments were held at baseline and at 12 months after baseline. All of the six sites were located in Tokyo, Chiba, Miyagi, and Kyoto. This study was approved by the Research Ethics Committee at the National Center of Neurology and Psychiatry (A2011-024). After participant recruit- ment and baseline BACS assessment were complete, the research manager, who was blinded to the study interventions and analyses, randomized participants with stratification by sex and the score of the BACS. In the TVS group, participants received the usual employment services currently used in Japan; these are based on the brokerage care management model. The care managers in the hospitals met the partici- pants at least once a month and engaged with com- munity facilities, which provided traditional employment services to this group. Ninety-four participants were randomly assigned

to the CR + SE or TVS groups. Verbal Memory, Working Memory, Letter Fluency, Processing Speed, and composite score of the BACS were improved to a greater extent in the CR + SE group after a 4-month intervention of cognitive remediation than in the TVS group. In addition to the competitive employment rate, total days employed, and total earnings during the follow-up period were signifi- cantly better in the CR + SE group after intervention

than in the TVS group (Sato et al., in preparation). The work outcomes of the CR + SE group were as follows: the average competitive employment rate was 0.79 (SD, 0.89), the total days employed was 48.4 days (SD, 53.0), and the total earnings was 180 269 Yen (SD, 223 150).

Intervention

Thinking Skills for Work program

Cognitive remediation was provided using computer software, CogPack (Marker Software, Germany). This program was developed for rehabilitation of higher brain dysfunction, and it contains 64 cognitive tasks to train verbal memory, working memory, atten- tion/vigilance, psychomotor speed, and executive function. Marker Software gave us permission to develop a Japanese-language version of the program for use in research settings.

Our cognitive remediation method is based on the Thinking Skills for Work program.13,15 We con- ducted 24 cognitive training sessions using CogPack, twice a week, with each session lasting about 45–60 min. We also conducted a weekly group ses- sion designed to promote the transfer of improved cognitive functioning to real-world situations. The trained therapists described below also provided participants with teaching compensation strategies or prompted additional practice if needed.

We developed a cognitive remediation manual for practitioners in order to standardize treatment across sites.18 Additionally, at least one therapist at each site had to take 1-day training courses twice to learn the cognitive remediation program before the study was started. Therapists involved in the intervention were familiar with psychiatric rehabilitation for schizophrenia, and were supervised during the study period by members of the research team who had several years’ experience with cognitive remediation.

In the computer cognitive training, participants were directed to practice a wide range of cognitive domains in both early and later phases of remedia- tion with adherence to the Thinking Skills Work program. Each participant could choose either pref- erable tasks or un-skilled tasks to enhance their interests or self-efficacy in the later phase. In addi- tion to computer exercises, participants joined a group session that was designed to facilitate connec- tions between the computer-assisted cognitive reme- diation and daily life or work performance. Participants talked about their weak or strong tasks

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Psychiatry and Clinical Neurosciences 2017; 71: 301–308 Effect of cognitive functioning on work 303

of computer exercises and discussed problem- solving or compensating strategies to complete tasks using some cognitive functioning in the early phase. In the middle and later phase, the roles of cognition in job performance, and problem-solving or com- pensatory strategies for dealing with common chal- lenges on the job were discussed using the skills learned in computer exercises to aid in setting and tracking individualized community life or work goals.

Supported employment Supported employment services were provided to participants after cognitive remediation therapy. In this study, these services adhered to the definition of supported employment, including some of the prin- ciples of the Individual Placement and Support model19 described in the Introduction section. During the study period, the staff for the CR + SE

group received 1-day training sessions 5 times to learn skills for supported employment.

Outcome measures

The subjects were evaluated in the following assess- ments during the pre- and post-intervention phases (after 4 months from the baseline) within 1 month, and after the follow-up phase with supported employment (after 12 months from the baseline).

1 The main outcomes were competitive employ- ment rates, total days employed, and total earn- ings during the follow-up period. The employment status and work tenures (days) of each participant were tracked daily or monthly by the care manager during the 12-month follow-up. Competitive employment was operationally defined as a job paying at least minimum wage (as established in Japanese law), with 5 or more work hours per week, for which anyone can apply, and is not controlled by a service agency.

2 Cognitive functioning was assessed using the BACS. The BACS includes six measures of cogni- tive functioning in the following domains: Verbal Memory, Attention, Verbal Fluency, Working Memory, Executive Functioning, and Psychomo- tor Processing. A composite score of overall cogni- tive performance is also provided. The BACS has established reliability and validity and has good sensitivity for the types of cognitive deficits associ- ated with schizophrenia. Normalized standard

scores of the BACS for each age category have already been reported in Japan.20

3 Clinical measures were assessed at baseline and after 12 months from baseline using scores of the Positive and Negative Syndrome Scale21,22

(PANSS), the Hamilton Depression Scale23

(HAM-D), and the Global Assessment of Func- tioning24 (GAF) in order to show the clinical con- ditions for participants. Clinical outcomes were assessed by participants’ attending doctors or trained psychologists at each site, with no person being masked for allocation concealment.

4 Social functioning was assessed with the Life Assessment Scale for Mental Illness25,26 (LASMI), which was rated based on reports from clients, information of care-givers, and therapist observa- tions over the previous month. The LASMI yields a rating of functioning in five domains: Daily Liv- ing, Interpersonal Relations, Work, Endurance and Stability, and Self-recognition. We used the Interpersonal Relations and Work subscales of the LASMI in this study, because the aim of the study was to improve vocational abilities through cog- nitive remediation. The Interpersonal Relations subscale consists of 13 items, which are derived from basic communication skills, such as facial expression, to informal relations with family or friends. The Work subscale consists of 10 items, which include work skills and the employee’s role that might be expected in a company. Each item of the LASMI is evaluated on a 5-point Likert scale, and a higher score indicates a greater need for support in each activity. The score of each sub- scale is calculated by summing all the items in the subscale.

5 The Japanese Adult Reading Test 27,28 (JART) was used to evaluate the estimated premorbid IQ. The JART is the Japanese version of the National Adult Reading TestT29 (NART), using 50 Japanese irreg- ular words, all of which are Kanji (ideographic script) compound words. NART is a valid scale for evaluating premorbid IQ based on reading performance.

We conducted two training sessions for the raters at each site who assessed the measures above.

Statistics

Participants who had at least one assessment made up the intention-to-treat sample, and the Last

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304 E. Ikebuchi et al. Psychiatry and Clinical Neurosciences 2017; 71: 301–308

Observation Carried Forward method was used. For statistical analysis, we used SPSS 21 software. We conducted logistic regression analyses for

dichotomous variables and multiple linear regres- sion analyses for continuous variables. In logistic regression analyses for the employment outcome, we allocated dummy variables as follows: 0 meant unemployed and 1 meant employed in regards to employment outcome. Competitive employment rates, total days employed, and total earnings were dependent variables. Independent variables were demographic variables except sex and clinical vari- ables at baseline, and the change in the composite score of BACS, which were used to reduce the num- ber of independent variables because the total num- ber of subjects was moderate.

Ethical procedure

We performed this trial in accordance with the Dec- laration of Helsinki and Ethical Guidelines for Clini- cal Studies of the Ministry of Health, Labor and Welfare. This study was approved by the institu- tional review board or ethics committee at each site,

and oral and written informed consent was obtained from all participants.

RESULTS

Characteristics of participants in this study

Outcome data for 47 participants in the CR + SE group were available for multiple regression analy- sis. All of the CR + SE group participants who were included in the analyses attended at least 80% of the sessions for the cognitive remediation program, although four took 5 months to complete the program.

Table 1 shows participants’ demographic data and cognitive and clinical conditions. Of the total parti- cipants, approximately 60% were male, and over 80% were diagnosed with schizophrenia. The mean age was approximately 35 years old.

Logistic and multiple linear regression analysis (Table 2)

None of the independent variables significantly con- tributed to the competitive employment rate. The

Table 1. Demographics and clinical conditions of participants at baseline

Subjects (n = 47)

Sex Male n (%) 28 (60) Female 19 (40)

Age (years) Mean (SD) 34.83 (7.00) Diagnosis Schizophrenia n (%) 40 (84.40)

Depression 4 (8.90) Bipolar 3 (6.70)

Years of education Mean (SD) 14.48 (2.70) Work in the past year (more than 30 days) Worked n (%) 14 (28.90)

Did not work 33 (71.10) Chlorpromazine calculation for medication per day† Mean (SD) 573.61 (640.25) JART 104.15 (10.52) PANSS schizophrenia only n = 40 62.03 (17.68) HAM-D bipolar and depression only n = 7 12.86 (4.71) GAF 49.75 (8.01) LASMI-I 1.16 (0.65) LASMI-W 1.33 (0.63) BACS-J composite score −1.12 (0.62)

†Mean of chlorpromazine per day was only calculated from participants with a diagnosis of schizophrenia (n = 40). BACS-J, Japanese version of the Brief Assessment of Cognition in Schizophrenia; GAF, Global Assessment of Functioning; HAM-D, Hamilton Depression Scale; JART, Japanese Adult Reading Test; LASMI-I, Life Assessment Scale for Mental Illness Interpersonal Relations subscale; LASMI-W, Life Assessment Scale for Mental Illness Work subscale; PANSS, Positive and Negative Syndrome Scale.

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Psychiatry and Clinical Neurosciences 2017; 71: 301–308 Effect of cognitive functioning on work 305

change in the composite score of BACS between the pre- and post-cognitive remediation contributed sig- nificantly to the total days employed and total earn- ings. The composite score of BACS after cognitive remediation was significantly better improved than baseline assessment (Fig. 1). None of the baseline demographic or clinical variables significantly con- tributed to the work-related outcomes.

DISCUSSION Improvement of cognitive functioning with cogni- tive remediation significantly contributed to the quality of work outcome (total days employed and total earnings) of supported employment. Factors influencing the competitive employment rate should be further studied. Some factors that were not evalu- ated in this study may impact the work outcome because the determinant rates were moderate in logistic and multiple linear regression analysis. Suc- cess of vocational services depends greatly on social factors, such as the relation between fluctuation of the employment rate and the economic state of the society, which could not be controlled or exactly evaluated. Although previous studies of cognitive remedia-

tion have reported the efficacy of improving cogni- tive functioning, it has been unclear whether improvement of cognitive functioning directly trans- lates to improved social functioning.30–33 However, some studies in which cognitive remediation was added to psychiatric rehabilitation showed the

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© 2016 The Authors Psychiatry and Clinical Neurosciences © 2016 Japanese Society of Psychiatry and Neurology

306 E. Ikebuchi et al. Psychiatry and Clinical Neurosciences 2017; 71: 301–308

greatest impact on psychosocial functioning.12,34,35

It is possible that cognitive remediation improves the capacity to learn, and that in the absence of con- certed learning opportunities, improved cognitive functioning does not automatically lead to improved psychosocial functioning.32 Our findings are consist- ent with previous research on cognitive remediation showing significant improvements in cognitive func- tioning, as well as improvements in social function- ing, when cognitive remediation was added to psychiatric rehabilitation, compared to psychiatric rehabilitation alone.31,36 The program of this study focused on enhancing the transference of learned abilities to real-world situations with group sessions and a supported employment program. These char- acteristics might lead improvement of cognitive functioning into real-world functioning.16,18

Supported employment has been shown to be effective, as previously discussed in the Introduction section. However, the quality and duration of work gained under supported employment remains unclear. Bell et al.14 reported that neurocognitive therapy improved supported employment outcomes among schizophrenia and schizoaffective disorder patients, as evaluated using cumulative rates of com- petitive employment and worked hours. McGurk et al.31 reported that persons with severe mental ill- ness who had not obtained competitive work despite receiving the help of a high-fidelity supported employment program showed better jobs obtained, weeks worked, and wages earned for competitive employment outcomes after cognitive remediation therapy (the Thinking Skills for Work program) than those that continued with the supported employ- ment service only. These studies are consistent with our finding. Adding cognitive remediation to sup- ported employment would be effective for persons with severe mental illness and cognitive dysfunction if they hope to work longer and do better quality work in competitive employment.

Strengths and limitations of this study

Our study was conducted with a cognitive remedia- tion program that has previously been reported to be effective in Japan.16,18 As the research sites of this study had experienced supported employment ser- vices for several years, persons with severe mental illness and cognitive dysfunction showed good com- petitive employment rates in this study.

The number of subjects in this study was not large. Therefore, the results of the multiple regres- sion analysis might not be generalizable to other set- tings. The influence of the improvement of each domain of cognitive functioning on work outcomes needs to be researched in a larger-sample study in the future. A longer observation period for the tra- jectory of improvement of social outcome is also needed. It is well known that changing social out- comes after supported employment requires as much as 2 years or more. Further studies are needed to overcome these limitations.

ACKNOWLEDGMENTS This study is supported by the Health Labor Sciences Research Grant of the Ministry of Health, Labour and Welfare, Japan (H23-001: A study on the model construction and the evaluation of community psy- chiatry to promote community lives).

DISCLOSURE STATEMENT There is no conflict of interest to disclose.

AUTHOR CONTRIBUTIONS Conception and design of the study: E.I., S.S., J.- I. Acquisition and analysis of data: S.S., S.Y., M.S., A.T., M.S., N.S., M.N., N.H., Y.W., E.I. Drafting the manuscript: E.I. Drafting the figures and tables: S.S., E.I.

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