Profile and Determinants of Disability in Psychotic Disorders in Nigeria

Original Paper

Abstract

We compared profile and predictors of disability among 210 patients with schizophrenia, schizoaffective disorder, bipolar I disorder with psychosis and depression with psychosis, respectively in a Nigerian clinical population, using the WHO Disability Assessment Schedule, (2.0). Severity of psychosis was determined with Positive and Negative Symptoms Scale, functioning was assessed using the Global Assessment of Functioning Scale, medication adherence with the Medication Adherence Questionnaire. Analyses were by SPSS 20.0. There were remarkable differences in the predictors of disability across these psychotic disorders. The findings strengthens the significance of psychosocial rehabilitation in patients with psychosis as clinical remission and medication adherence did not equate functional recovery.

Keywords

Schizophrenia Schizoaffective disorder Bipolar Disorder Depression Disability Community-rehabilitation 

Introduction

Results for the Global Burden of Disease (GBD) Study in 1990 showed that 21.4% of the total global burden of diseases, representing the highest, were in sub-Saharan Africa (Murray and Lopez 1997), and in 2001 almost half this burden was due to non-communicable diseases (Lopez et al. 2006). Specifically, neuropsychiatric disorders have been reported to account for 17.6% of all year lost due to disabilities (YLDs) in Africa. Despite this, public health initiatives have appeared to concentrate on prevention and intervention efforts on other major communicable diseases (Institute of Medicine Committee on Nervous System Disorders in Developing 2001). In Nigeria, neuropsychiatric disorders rank high in their disability adjusted life year (DALY) estimates. Hence, adults with mental illnesses are more likely to be experiencing poorer overall health than those without, they are also more disabled in the performance of occupational role and are more likely to report more disability days in the previous month. Twelve-month follow-up of cases in primary care in Nigeria shows that 18% still meet criteria for diagnoses. Also, baseline disorder is often associated with occupational disability and poor overall health at 12 months (Gureje and Bamidele 1999).

In Nigeria, several contextual factors are responsible for the disability associated with mental disorders. One is the poor knowledge about the aetiology of mental disorders, poor attitude to the illness and the associated stigma (Gureje et al. 2005), which creates a lot of barriers in treatment seeking (Lasebikan 2016). For example, results from an earlier study in Nigeria showed that <1% of those with any 12 month mental disorder had received any intervention (Gureje and Lasebikan 2006) and when they did, treatment was inadequate or characterized by an initial alternative use of alternative practitioners (Lasebikan et al. 2012), thereby making them present to formal mental health care service with disabilities. These, coupled with lack of enabling laws in Nigerian to protect the rights of the mentally ill in regard to treatment, employment, rights and privileges, poor national health profile and serious dearth in the number of all cadres of mental health specialists are other contributory factors for disability in mental disorders in Nigeria (Gureje 2007).

Despite clear diagnostic differences between schizophrenia, schizoaffective disorder, bipolar disorder and major depression (World Health Organization 1994; American Psychiatric Association 1994), there are indications that these disorders are phenotypically similar (Crow 1995). While schizophrenia and bipolar have commonalities in the areas of symptom profile, epidemiological characteristics and response to dopamine blockade (Murray et al. 2004), schizophrenia and depression are similar in familial predisposition (Maier et al. 1993), affective psychoses are similar to schizophrenia in the degree of disability (Green 2006; Gureje et al. 2002) and schizoaffective disorder closely resemble schizophrenia in terms of disability (Szoke et al. 2008) and bipolar disorder similar to schizophrenia in cognitive impairment (Green 2006). Thus, exploring the possibility of a common or similar or differential disability profiles among these major mental disorders in Nigeria will add to the body of knowledge on the determinants of disability in them. This may be relevant in the development of a comprehensive mental health services Nigeria, a country where psychiatric rehabilitation had received very limited attention (Coker et al. 2011) and where there are limited data on disability in psychotic disoders.

In this present study, we compared disability in schizophrenia, schizoaffective, bipolar disorder with psychosis and depression with psychosis in a psychiatric unit of a general hospital in Ibadan, Nigeria.

Methods

Study Area

We carried out the study at the outpatients department of the Psychiatric Unit of the State Specialists Hospital, Ibadan, Nigeria between January and December 2011.

Consecutive patients, who scored positive on the psychosis screen and met the DSM IV criteria for schizophrenia, schizoaffective disorder or bipolar I disorder with psychosis and depression with psychosis using the Structured Clinical Interview for DSM IV axis I disorder (SCID) (First et al. 1996) were recruited for the study. An effort was made not to duplicate respondents by endorsing their hospital attendance cards as they were interviewed.

In all, 210 patients who met the inclusion criteria were recruited in each of the four groups. In order to validate information obtained from the patients, we recruited only those who were accompanied by their caregivers to the hospital.

Exclusion Criteria

Subjects who scored negative on the psychosis screen were excluded from the study. Those who did not fulfil the diagnostic criteria for schizophrenia, schizoaffective disorder, bipolar 1 disorder with psychosis and psychotic depression using the SCID, were also excluded from the study. Other exclusion criteria include having more than one principal diagnoses such as co morbid alcohol or substance use disorders, and moderate to severe disabling general medical condition. A threshold of 5 years was set and participants with clear evidences that the illness had been on for over the set threshold period were excluded from the study.

Study Design

This was a comparative study that utilized total sampling of all patients with psychosis that regularly attended the psychiatric unit of the state hospital during the study period.

Ethical Considerations

Permission for the study was obtained from the Ethical and Review Board of the Ring Road State Hospital, to ascertain that the methodology of the study was in accordance with the 1964 Helsinki Declaration and its later amendments. We ensured that the study did not contravene laid down guidelines for experiments involving human beings. Informed consent was obtained from each of the subjects and/or their relations after the objective of the exercise have been spelt out for them.

Pilot Study

We pilot tested all instruments of data collection were pilot tested among 30 patients with schizophrenia attending the psychiatric outpatients department of the study center prior to the commencement of the study (not part of current study). This pilot study was to determine the applicability, administration time and inter-rater reliability of the interviewers and also to determine any clinical dilemma that could be hampering the smooth running of the study. All interviewers had significant inter-rater reliability.

Measures

Socio-demographic Questionnaire

Instruments of Data Collection included a socio-demographic questionnaire that yielded information about social-demographic characteristics of respondents, including age of respondents, gender, educational background, age of onset of illness, medication adherence and clinical state (remission or symptomatic) and severity of psychosis.

World Health Organization Disability Assessment Schedule 2.0 (WHODAS 2.0)

The WHO Disability Assessment Schedule 2.0 is a 12-item standardized instrument for assessing disabilities. It was developed to supersede the WHODAS II. It is a WHO instrument that has cross-cultural reliability and applicability. It assesses health and disability in mental disorders, but is applicable in neurological and addictive disorders. It has the advantage of being simple and quick to administer, (5–20 min).

This instrument has been used in several studies in Nigeria including a recent comparative analysis of disability in individuals with bipolar affective disorder and schizophrenia in a Sub-Saharan African mental health hospital (Adegbaju et al. 2013). Each question of the WHO-DAS 2.0 is usually rated from 1 to 5. No difficulty (1), mild difficulty (2), moderate difficulty (3), severe difficulty (4), extreme difficulty (5).

Scoring

The simple scoring method was used in this study was scores ranging from 1 to 5 were assigned to each item and computed by simple addition. The sum of the items in each domain was used in describing the degree of functional disability.

Global Assessment of Functioning Scale (GAF)

The Global Assessment of Functioning (GAF) scale (American Psychiatric Association 1994), is a 100-point single-item rating scale used by a clinician to determine the overall functioning of a patient during a particular time (for example, at the time of the evaluation or for at least a few months during the past year). It is derived from the Global Assessment Scale (GAS) which has established psychometric properties. Joint reliability on the GAS and the GAF scale across several studies ranged from 0.61 to 0.91 indicating fair to excellent agreement (Endicott et al. 1976). The functional level of the patient over the past 1 month was assessed in this study with GAF.

Remission of Psychosis

Remission of psychotic symptoms was defined using DSM IV criteria of “absence of delusions, hallucinations, disorganized speech, grossly disorganized or catatonic behavior, and negative symptoms” for at least 6 months prior to the interview (American Psychiatric Association 1994).

For the patients in the bipolar I with psychosis, an additional criterion was “absence or minimal symptoms of both mania and depression for at least 1 week” (Hirschfeld et al. 2007).

For the patients in the psychotic depression, an additional criterion was “absence or minimal symptoms of depression for at least 2 weeks”.

Positive and Negative Syndrome Scale (PANSS)

Positive and Negative Syndrome Scale (PANSS) was adapted from the Brief Psychiatric Rating Scale (BPRS) (Overall and Gorham 1962) and the Psychopathology Rating Schedule (PRS) (Singh and Kay 1975). It is a 30-item instrument that addresses both the presence and severity of symptoms. Of the 30 items, 7 constitutes a Positive Scale, 7 make up a Negative Scale, and the remaining 16 General Psychopathology. The PANSS has been used in many studies in Nigeria (Lasebikan et al. 2012). The PANSS was used to assess the severity of psychosis.

Medication Adherence

The 4-item self-report medication adherence questionnaire (Morisky et al. 1986) was used to assess medication adherence. The instrument yields a “yes” or “no” response to questions that probes into ways in which patients may fail to take their prescribed medications and has also been previously used in Nigeria (Adewuya and Ola 2008).

Training and Quality Control

The interviewers were six in all and were psychiatrists and senior psychiatric residents. All received a 2-week training conducted by VO. They all had prior experience in clinical and field studies. A 3-day debriefing and review of all protocols was carried out after a pilot survey that was carried out in a private mental health facility. There was a significant inter-rater reliability in all the constructs that were measured. We concluded that all instruments of data collection were applicable for the main study and that research adherence was possible.

Data Management and Analyses

The questionnaires were serialized, cleaned, edited and safely stored; thereafter information yielded by each was entered directly into the computer using the SPSS Software Version 15.0. Chi square statistics were used to analyze categorical two by two data, while the independent test and ANOVA were used to compare continuous variable.

Post hoc pairwise comparisons were carried out using Tukey test for continuous variables.

All Chi squares were Yates or Bonferonni adjusted. For multivariate analysis of disability in psychosis, four models of linear regression analyses were carried out using WHO DAS score of each of the four psychotic disorders as the dependent variables for each of the four models. All variables that were significantly associated with disability in each of the four groups during univariate analysis were entered into the regression equation as independent variables. We adjusted for the age of patients, noting that age is a natural determinant of disability. All analyses were conducted at 95% CI, p < 0.05.

Results

Demographic and Clinical Differences (Table 1)

In this study, there was a significant difference in the mean age of the respondents in the four groups, F = 13.8, p < 0.001. Post hoc tests show that the difference was due to the mean age of the schizophrenia group, being significantly lower than the bipolar group, p < 0.001 and the depression group, p < 0.001 and bipolar group being significantly younger than the depression group p < 0.001.

There was also a significant difference in the mean years of education of the respondents across the four groups, F = 15.6, p < 0.001 (Table 1). Post hoc tests show that this was accounted for by a significantly lower mean years of education of education of the schizophrenia group, being lower than the bipolar group and the depression group, p < 0.001 respectively, and that of the schizoaffective disorder group being significantly lower than that of the bipolar group, p = 0.003, and the depression group, p < 0.001 (not in any table).

Table 1

Sociodemographic, clinical profile and disability by mental disorder

Demographic and clinical characteristics

Schizophrenia

Schizoaffective disorder

Bipolar disorder

Depression

F

df

p

Mean

SD

Mean

SD

Mean

SD

Mean

SD

Age

29.26

9.67

31.31

8.74

33.43

9.49

34.80

9.75

13.8

3

<0.001

Age at onset

25.21

9.46

29.52

7.49

31.29

8.77

33.21

8.05

30.9

3

<0.001

Years of education

11.64

3.21

12.13

3.51

13.27

3.44

13.59

3.34

15.6

3

<0.001

Mean WHODAS

24.93

7.69

22.27

10.55

18.08

4.68

25.16

5.95

39.99

3

<0.001

 

n

%

n

%

n

%

n

%

X2

df

p

Gender

 Male

115

54.8

100

47.6

104

49.5

77

36.7

14.6

3

0.002BS

 Female

95

45.2

110

52.4

106

50.5

133

63.3

   

Marital status

 Married

64

30.5

82

39.0

77

36.7

50

23.8

30.8

3

<0.001BS

 Unmarried

146

69.5

128

61.0

133

63.3

160

76.2

   

Religion

 Christianity

77

36.7

71

33.8

72

34.3

78

37.1

0.8

3

0.9

 Islam

133

63.3

139

66.2

138

65.7

132

62.9

   

Occupation

 High level professional

3

1.4

40.9

9

<0.001BS

 Skilled worker

15

7.1

20

9.5

24

11.4

37

17.6

   

 Semi-skilled/unskilled

81

38.6

83

39.5

96

45.9

45

29.4

   

 Unemployed

114

54.3

107

51.0

90

42.9

125

59.5

   

Employment

 Employed

96

45.7

103

49.0

120

57.1

85

40.5

12.3

3

0.006BS

 Unemployed

114

54.3

107

51.0

90

42.9

125

59.5

   

BS Bonferonni significant

Also, there was a significant difference in the mean disability score of the four groups, F = 39.99, p < 0.001. The post hoc test shows that this difference was due to a higher mean score of the schizophrenia compared with schizoaffective disorder, p = 0.002, bipolar disorder, p < 0.002, and a higher mean score for depression compared with bipolar disorder, p < 0.001 and schizoaffective disorder, p = 0.001.

Furthermore, there were significant gender differences in all the four groups, X2 = 30.8, p < 0.001 (Table 1). Post hoc pairwise comparisons show that the difference was due to the schizophrenia group having a higher proportion of male patients than the bipolar group, X2 = 6.0, p = 0.01, and also the depression group X2 = 13.1, p < 0.001 (not in any table).

There was also a significant difference in the marital status of the patients across the four groups, X2 = 30.8, p < 0.001 (Table 1). Post hoc pairwise comparisons show that this difference was accounted for by a higher proportion of patients in the depression being unmarried compared with schizoaffective disorder, X2 = 10.6, p = 0.001, and also when compared with bipolar disorder, X2 = 7.6, p < 0.01 (not in any table).

The result also shows a significant difference across the four groups in their occupation. X2 = 40.9, p < 0.001. Furthermore, the results show a significant difference in the employment status across the four groups, X2 = 12.5, p = 0.006. Post hoc tests show that this was accounted for by a higher proportion of patients with schizophrenia being unemployed compared with the patients with bipolar disorder, X2 = 11.1, p < 0.001.

WHODAS Comparisons Across Groups; Results of Post-hoc Tests not in any Table (Table 2)

Age and WHODAS Scores

Among patients who were <21 years of age, there was a significant difference in the mean WHODAS scores cross the four groups F = 20.5, p < 0.001 (Table 2).

Table 2

Demographic and clinical correlates of disability across the four disorders

 

Schizophrenia

Schizoaffective disorder

Bipolar Disorder

Depression

F

P

Mean

SD

Mean

SD

Mean

SD

Mean

SD

Age

 <25

28.83

6.70

25.22

11.21

18.08

3.70

24.06

4.97

20.5

<0.001

 25–34

23.93

7.88

28.06

9.57

19.68

5.54

25.07

6.01

17.3

<0.001

 35–44

21.33

5.74

19.53

8.86

17.21

3.97

25.03

5.98

16.2

<0.001

 45–53

15.59

3.94

17.76

7.66

15.43

2.87

26.65

6.68

31.5

<0.001

Gender

 Male

24.31

6.65

24.94

7.75

18.25

3.55

21.28

2.37

27.0

<0.001

 Female

18.77

8.05

24.91

7.67

17.95

7.73

27.41

6.23

29.7

<0.001

Marital status

 Married

24.15

5.48

12.91

3.90

14.67

2.27

20.63

2.24

143.3

<0.001

 Unmarried

25.26

8.48

26.01

10.44

20.35

4.50

26.58

6.04

24.6

<0.001

Education

 No formal education

25.92

7.12

26.23

1.05

17.68

6.48

25.05

6.40

19.6

<0.001

 Formal education

24.24

7.74

21.84

10.57

18.16

4.20

25.28

5.89

36.7

<0.001

Employment

 Employed

21.52

9.10

20.39

7.69

17.23

4.57

24.10

5.18

21.5

<0.001

 Unemployed

25.17

10.87

24.06

7.69

19.32

4.60

27.04

6.74

14.8

<0.001

Clinical state

 Symptomatic

25.07

7.07

31.40

2.70

27.55

3.75

33.22

1.52

72.6

<0.001

 Remission

14.63

2.29

14.82

4.06

14.25

1.61

21.30

1.89

173.1

<0.001

Age of onset (years)

 <21

27.31

7.14

23.69

10.95

20.74

5.24

32.23

4.68

4.78

0.004

 21–30

22.72

7.63

19.10

9.39

16.81

3.50

27.03

6.76

36.2

<0.001

 31–40

18.13

1.39

19.67

0.37

14.91

2.80

22.50

3.58

68.6

<0.001

 >40

12.50

0.23

  

Medication adherence

 Yes

20.37

5.92

17.55

9.04

14.72

2.56

22.69

4.43

35.0

<0.001

 No

27.45

7.42

25.53

10.32

20.59

4.32

28.33

6.15

24.6

<0.001

Post-hoc multiple pairwise comparisons of mean WHODAS scores:

Schizophrenia higher bipolar disorder p < 0.001.

Schizophrenia higher depression p = 0.002.

Schizoaffective disorder higher bipolar disorder p < 0.001.

Depression higher than bipolar p = 0.001.

Among patients who were between 25 and 34 years of age, there was a significant difference in the mean WHODAS scores across the four groups F = 17.3, p < 0.001 (Table 2).

Post-hoc multiple pairwise comparisons of mean WHODAS scores:

Schizophrenia lower than schizoaffective disorder p = 0.004.

Schizophrenia higher than bipolar disorder p = 0.004.

Schizoaffective disorder higher than in bipolar disorder p < 0.001.

Among patients who were between 35 and 44 years of age, there was a significant difference the mean WHODAS scores across the four groups F = 16.2, p < 0.001(Table 2).

Post-hoc multiple pairwise comparisons of mean WHODAS scores:

Schizophrenia higher than in bipolar disorder p = 0.01.

Depression higher than in bipolar disorder p < 0.001.

Depression higher than schizoaffective disorder p < 0.001.

Among patients who were 45 years and above, there was a significant difference in the mean WHODAS scores across the four groups F = 31.5, p < 0.001 (Table 2).

Post-hoc multiple pairwise comparisons of mean WHODAS scores:

Schizophrenia and schizoaffective disorder lower than depression p < 0.001 respectively.

Gender and WHODAS Scores

Among men, there was a significant difference in the mean WHODAS scores across the four groups F = 27.2, p < 0.001.

Post-hoc multiple pairwise comparisons of mean WHODAS scores:

Schizophrenia higher than bipolar disorder p < 0.001.

Schizophrenia higher than depression p = 0.002.

Schizoaffective disorder higher than bipolar disorder p < 0.001.

Schizoaffective disorder higher than depression p < 0.001.

Among women, there was a significant difference in the mean WHODAS scores across the four groups F = 29.7, p < 0.001.

Post-hoc multiple pairwise comparisons of mean WHODAS scores:

Schizophrenia lower than in schizoaffective disorder p < 0.001.

Schizophrenia lower than depression p < 0.001.

Schizoaffective disorder higher than bipolar disorder p < 0.001.

Marital Status and WHODAS Scores

Among married respondents, there was a significant difference in the mean WHODAS scores across the four groups F = 143.3, p < 0.001 (Table 2).

Post-hoc multiple pairwise comparisons of mean WHODAS scores:

Schizophrenia higher than schizoaffective disorder p < 0.001.

Schizophrenia higher than bipolar disorder p < 0.001.

Schizophrenia higher than depression p < 0.001.

Schizoaffective disorder lower than bipolar disorder p = 0.01.

Schizoaffective disorder lower than and depression p < 0.001.

Among unmarried respondents, there was a significant difference in the mean WHODAS scores across the four groups F = 24.6, p < 0.001 (Table 2).

Post-hoc multiple pairwise comparisons of mean WHODAS scores:

Schizophrenia higher than bipolar disorder p < 0.001.

Schizoaffective disorder higher than bipolar disorder p < 0.001.

Depression higher than bipolar disorder p < 0.001.

Educational Status and WHODAS Scores

Among respondents with no formal education, there was a significant difference in the mean WHODAS scores across the four groups F = 19.6, p < 0.001 (Table 2).

Post-hoc multiple pairwise comparisons of mean WHODAS scores:

Schizophrenia higher than bipolar disorder p < 0.001.

Schizoaffective disorder higher than bipolar disorder p < 0.001.

Among respondents who had formal education, there was a significant difference in the mean WHODAS scores across the four groups F = 36.8, p < 0.001 (Table 2).

Post-hoc multiple pairwise comparisons of mean WHODAS scores:

Schizophrenia higher than schizoaffective disorder p < 0.001.

Schizophrenia higher than bipolar disorder p < 0.001.

Schizoaffective disorder higher than in bipolar disorder p < 0.001.

Depression higher than in schizoaffective disorder p < 0.001.

Depression higher than bipolar disorder p < 0.001.

Employment Status and WHODAS Scores

Among respondents who were in employment, there was a significant difference in the mean WHODAS scores across the four groups F = 21.6, p < 0.001 (Table 2).

Post-hoc multiple pairwise comparisons of mean WHODAS scores:

Schizophrenia higher than bipolar disorder p < 0.001.

Schizoaffective disorder higher than in bipolar disorder p < 0.001.

Schizoaffective disorder higher than depression p < 0.001.

Among respondents who were unemployment, there was a significant difference in the mean WHODAS scores across the four groups F = 14.8, p < 0.001 (Table 2).

Post-hoc multiple pairwise comparisons of mean WHODAS scores:

Schizophrenia higher than in bipolar disorder p < 0.001.

Schizoaffective disorder higher than bipolar disorder p = 0.003.

Clinical State and WHODAS Scores

Among respondents who were clinically symptomatic, there was a significant difference in the mean WHODAS scores across the four groups F = 72.4, p < 0.001 (Table 2).

Post-hoc multiple pairwise comparisons of mean WHODAS scores:

Schizophrenia lower than schizoaffective disorder p < 0.001.

Schizophrenia lower than bipolar disorder p = 0.001.

Schizophrenia lower than depression p < 0.001.

Schizoaffective disorder higher than bipolar disorder p < 0.001.

Schizoaffective disorder lower than depression p = 0.001.

Among respondents who were in remission, there was a significant difference in the mean WHODAS scores across the four groups F = 173.1, p < 0.001 (Table 2).

Post-hoc multiple pairwise comparisons of mean WHODAS scores:

Depression higher than schizophrenia p < 0.001.

Depression higher than schizoaffective disorder p < 0.001.

Medication Adherence and WHODAS Scores

Among respondents who were medication adherent, there was a significant difference in the mean WHODAS scores across the four groups F = 35.0, p < 0.001 (Table 2).

Post-hoc multiple pairwise comparisons of mean WHODAS score:

Schizophrenia higher than in bipolar disorder p < 0.001.

Schizoaffective disorder higher than bipolar disorder p = 0.008.

Depression higher than bipolar disorder p < 0.001.

Depression higher than schizoaffective disorder p < 0.001.

Among respondents who were medication non-adherent, there was a significant difference in the mean WHODAS scores across the four groups F = 24.6, p < 0.001 (Table 2).

Post-hoc multiple pairwise comparisons of mean WHODAS scores:

Schizophrenia higher than bipolar disorder p < 0.001.

Schizoaffective disorder higher than bipolar disorder p < 0.001.

Depression higher than in bipolar disorder p < 0.001.

Age of Onset <21 Years

Among patients whose age of onset of illness was less than 21 years of age, there was a significant difference in the mean WHODAS scores cross the four groups F = 24.8, p = 0.004 (Table 2).

Post-hoc multiple pairwise comparisons of mean WHODAS scores:

Schizophrenia higher than in bipolar disorder p = 0.01.

Age of Onset 21–30 Years

Among patients whose age of onset of illness was between 21 and 30 years, there was a significant difference in the mean WHODAS scores cross the four groups F = 36.22, p < 0.001 (Table 2).

Post-hoc multiple pairwise comparisons of mean WHODAS scores:

Schizophrenia higher than schizoaffective disorder p = 0.006.

Schizophrenia higher than bipolar disorder p < 0.001.

Schizophrenia lower than depression p < 0.001.

Bipolar disorder lower than depression p < 0.001.

Age of Onset 31–40 Years

Among patients whose age of onset of illness was between 31 and 40 years, there was a significant difference in the mean WHODAS scores cross the four groups F = 68.6, p < 0.001 (Table 2).

Post-hoc multiple pairwise comparisons of mean WHODAS scores:

Schizophrenia higher than bipolar disorder p < 0.001.

Schizophrenia lower than depression p < 0.001.

Schizoaffective disorder higher than bipolar disorder p < 0.001.

Schizoaffective disorder lower than depression p < 0.001.

Within Group Comparisons (Table 3)

There were similar and different demographic associations with the mean disability score based on the diagnostic grouping. In schizophrenia, schizoaffective disorder and bipolar disorder mean disability scores reduced with increasing age, p < 0.001 respectively. Male gender in schizophrenia and female gender in depression were found to be associated with higher levels of disability, p < 0.001 respectively. Being unmarried, was also found to be associated with higher levels of disability in schizoaffective disorder, bipolar disorder and depression, p < 0.001 respectively. In schizophrenia, schizoaffective disorder and depression, lower level of education was associated with higher mean disability score, p = 0.03, 0.001, 0.02.

In all the 4 groups, the unemployed recorded a higher level of disability compared with the employed, schizophrenia and schizoaffective disorder p = 0.03 respectively, bipolar disorder and depression p = 0.001 respectively. Also, respondents in all the four groups who were symptomatic recorded a higher level of disability compared with those in remission, p < 0.001 respectively, while respondents who were not medication-adherent also reported higher mean disability score, p < 0.001.

In all the four groups, disability significantly reduced as age of onset at onset of illness increased, schizophrenia, bipolar disorder, depression, p < 0.001 respectively, schizoaffective disorder, p = 0.01 (Table 3).

Table 3

Demographic and clinical correlates of disability by type of mental disorder

 

Schizophrenia

F or t

p

Schizoaffective disorder

F or t

p

Mean

SD

Mean

SD

Age

 <25

28.83

6.70

19.7F

<0.001

25.22

11.21

11.4F

<0.001

 25–34

23.93

7.88

  

28.06

9.57

  

 35–44

21.33

5.74

  

19.53

8.86

  

 45–53

15.59

3.94

  

17.76

7.66

  

Gender

 Male

24.31

6.65

6.4t

<0.001

24.94

7.75

0.03F

1.0

 Female

18.77

8.05

  

24.91

7.67

  

Marital status

 Married

24.15

5.48

−1.0t

0.3

12.91

3.90

−9.0t

<0.001

 Unmarried

25.26

8.48

  

26.01

10.44

  

Education

 No formal education

25.92

7.12

3.1F

0.03

26.23

1.05

4.8F

0.001

 Elementary

24.73

8.15

  

23.98

10.58

  

 Secondary

22.86

7.60

  

22.69

9.46

  

 Post-secondary

22.04

3.90

  

21.34

   

Employment

 Employed

21.52

9.10

−2.1t

0.03

20.39

7.69

−2.2t

0.03

 Unemployed

25.17

10.87

  

24.06

7.69

  

Clinical state

 Symptomatic

25.07

7.07

10.3t

<0.001

31.40

2.70

39.5t

<0.001

 Remission

14.63

2.29

  

14.82

4.06

  

Age of onset (years)

 <21

27.31

7.14

14.7F

<0.001

23.69

10.95

4.3F

0.01

 21–30

22.72

7.63

  

19.10

9.39

  

 31–40

18.13

1.39

  

19.67

0.37

  

 >40

  

  

Medication adherence

 Yes

20.37

5.92

−7.1t

<0.001

17.55

9.04

−5.8t

<0.001

 No

27.45

7.42

  

25.53

10.32

  
 

Bipolar disorder

F or t

P

Depression

F or t

P

Mean

SD

Mean

SD

Age

 <25

18.08

3.70

7.7F

<0.001

24.06

4.97

1.6F

0.2

 25–34

19.68

5.54

  

25.07

6.01

  

 35–44

17.21

3.97

  

25.03

5.98

  

 45–53

15.43

2.87

  

26.65

6.68

  

Gender

    

25.16

   

 Male

18.25

3.55

0.5t

0.6

21.28

2.37

−8.3t

<0.001

 Female

17.95

7.73

  

27.41

6.23

  

Marital status

 Married

14.67

2.27

−10.71t

<0.001

20.63

2.24

−6.8t

<0.001

 Unmarried

20.35

4.50

  

26.58

6.04

  

Education

 No formal education

17.68

6.48

2.6F

0.05

25.05

6.40

3.4F

0.02

 Elementary

17.59

4.89

  

25.96

6.30

  

 Secondary

18.30

3.18

  

24.95

6.22

  

 Post-secondary

21.09

1.58

  

22.79

3.33

  

Employment

 Employed

17.23

4.57

−3.2t

0.001

24.10

5.18

−3.5t

0.001

 Unemployed

19.32

4.60

  

27.04

6.74

  

Clinical state

 Symptomatic

27.55

3.75

18.0t

<0.001

33.22

1.52

−49.9t

<0.001

 Remission

14.25

1.61

  

21.30

1.89

  

Age of onset (years)

 <21

20.74

5.24

18.4F

<0.001

32.23

4.68

55.0F

<0.001

 21–30

16.81

3.50

  

27.03

6.76

  

 31–40

14.91

2.80

  

22.50

3.58

  

 >40

12.50

0.23

      

Medication adherence

 Yes

14.72

2.56

−11.5t

<0.001

22.69

4.43

−7.7t

<0.001

 No

20.59

4.32

  

28.33

6.15

  

In all the four groups, there was a significant positive correlation between WHODAS scores and PANSS scores, but a significant negative correlation between WHODAS scores and GAF scores. There was also a significant negative correlation between PANSS scores and GAF scores (Table 4).

Table 4

Correlations between WHODAS, GAF and PANSS

DSM IV disorder

 

WHODAS

PANSS total

GAF

Schizophrenia

 WHODAS

r

1

0.207

−0.656

 PANSS total

r

0.207

1

−0.488

 P

 

0.003

<0.001

 GAF

r

−0.656

−0.488

1

 P

 

<0.001

<0.001

Schizoaffective disorder

 WHODAS

r

1

0.147

−0.773

 P

 

0.034

<0.001

 PANSS total

r

0.147

1

−0.203

 P

 

0.03

0.002

 GAF

r

−0.773

−0.203

1

 P

 

<0.001

0.02

Bipolar disorder

 WHODAS

r

1

0.333

−0.698

 P

 

<0.001

<0.001

 PANSS total

r

0.333

1

−0.547

 P

 

0.03

<0.001

 GAF

r

−0.698

0.547

1

 P

 

<0.001

<0.001

 

Depression

 WHODAS

r

1

0.897

−0.865

 P

 

<0.001

<0.001

 PANSS total

r

0.897

1

−0.795

 P

 

<0.001

<0.001

 GAF

r

−0.865

−0.795

1

Predictors of disability in schizophrenia were young age at onset of illness, p = 0.002, and low GAF, p < 0.001. Predictors of disability in schizoaffective disorder were poor medication adherence, p < 0.001, presence of clinical symptoms (not in remission) p = 0.015, being unmarried 0.04, high PANSS score p = 0.002 and reduced GAF p < 0.001 (Table 5).

Table 5

Predictors of disability in Schizophrenia and Schizoaffective disorder

 

Unstandardized coefficients

Standardized coefficients

t

Sig.

95% confidence interval for B

B

Std. error

Beta

Lower bound

Upper bound

Schizophrenia

   

 Constant

50.690

5.155

 

9.833

0.000

40.525

60.855

 Age at onset

−0.163

0.051

−0.205

−3.183

0.002

−0.264

−0.062

 Employment

−0.573

0.823

−0.036

−0.696

0.487

−2.195

1.049

 Medication adherence

0.647

1.593

0.040

0.406

0.685

−2.495

3.789

 Remission

−3.367

2.944

−0.206

−1.144

0.254

−9.173

2.438

 Sex

−0.470

0.836

−0.030

−0.562

0.575

−2.118

1.178

 Education

0.528

0.485

0.056

1.088

0.278

−0.429

1.484

 PANNS

−0.026

0.015

−0.112

−1.751

0.081

−0.054

0.003

 GAF

−0.302

0.050

−0.819

−6.086

0.000

−0.400

−0.011

Schizoaffective disorder

  

 Constant

38.089

4.059

 

9.384

0.000

30.086

46.092

 Age at onset

−0.014

0.051

−0.011

−0.268

0.789

−0.114

0.087

 Employment

−1.267

1.014

−0.052

−1.249

0.213

−3.266

0.733

 Medication adherence

−3.760

0.954

−0.176

−3.941

0.000

−5.641

−1.879

 Remission

2.605

1.062

0.121

2.453

0.015

0.511

4.699

 Education

0.343

0.599

0.027

0.572

0.568

−0.839

1.525

 Marriage

1.977

0.954

0.094

2.072

0.040

0.096

3.858

 PANNS

0.043

0.014

0.149

3.072

0.002

0.016

0.071

 GAF

−0.365

0.028

−0.640

−13.143

0.000

−0.420

−0.311

Predictors of disability in bipolar disorder were younger age at onset of illness, p = 0.013, poor medication adherence, p = 0.008, and low GAF, p < 0.001, while predictors of disability in depression were being unemployed p < 0.001, presence of clinical symptoms (not in remission) p = 0.003, being unmarried, high PANSS score, reduced GAF p < 0.001 respectively and female gender p = 0.03 (Table 6).

Table 6

Predictors of disability in bipolar disorder and depression

 

Unstandardized coefficients

Standardized coefficients

t

Sig.

95% confidence interval for B

B

Std. error

Beta

Lower bound

Upper bound

Bipolar disorder

 Constant

24.375

2.472

 

9.859

0.000

19.500

29.250

 Age at onset

−0.068

0.027

−0.137

−2.509

0.013

−0.121

−0.014

 Employment

0.197

0.483

0.021

0.408

0.684

−0.755

1.149

 Medication adherence

−1.914

0.713

−0.203

−2.686

0.008

−3.320

−0.509

 Remission

0.891

0.811

0.093

1.099

0.273

−0.708

2.490

 Marriage

0.925

0.581

0.095

1.591

0.113

−0.221

2.070

 PANNS

0.015

0.009

0.107

1.753

0.081

−0.002

0.033

 GAF

−0.112

0.022

−0.457

−4.986

0.000

−0.156

−0.068

Depression

 Constant

17.752

1.898

 

9.355

0.000

14.010

21.494

 Age at onset

0.026

0.014

0.043

1.840

0.067

−0.002

0.054

 Employment

1.181

0.293

0.096

4.029

0.000

0.603

1.759

 Medication adherence

0.091

0.325

0.008

0.279

0.781

−0.550

0.731

 Remission

1.152

0.389

0.097

2.961

0.003

0.385

1.918

 Marriage

1.609

0.376

0.116

4.285

0.000

0.869

2.350

 PANNST

0.124

0.011

0.503

11.345

0.000

0.102

0.145

 GAF

−0.092

0.012

−0.317

−7.478

0.000

−0.116

−0.068

 Sex

0.727

0.333

0.059

2.184

0.030

0.071

1.383

 Education

−0.118

0.166

−0.018

−0.711

0.478

−0.445

0.209

Discussion

In this study aimed at assessing profile and correlates of disability in psychoses, our results, briefly stated, indicate areas of similarities and differences in the sociodemographic, clinical profiles and disability among patients with schizophrenia, schizoaffective disorder, bipolar disorder and depression. To the best of the authors’ knowledge, this is the first study in Sub-Saharan Africa, where disability in these four disorders was compared. The findings in the study are presented herein.

Demographic Differences Across the Disorders

We found that schizoaffective disorder, was somewhere between schizophrenia, and both bipolar and depressive psychoses, in certain demographic profiles such as the mean age at onset, age of respondents, years of education and in employment status.

For gender, a higher proportion of men were found to have schizophrenia and women, depression. Despite this, there was no significant gender difference between schizophrenia and schizoaffective disorder and between schizoaffective disorder and bipolar disorder. Although in support of an earlier study (Piccinelli and Wilkinson 2000), we found that depression was more common in women. Nevertheless, we also found no significant gender variability between schizophrenia and bipolar disorder. This is also in line with an earlier study (Canuso and Pandina 2007). Similar to an earlier observation (Gureje et al. 2002), marriage was a problem in all the four groups, suggesting that psychotic patients may have difficulties in establishing or sustaining marital relationships.

We also found that the unemployment status in schizophrenia was not significantly different from that reported in schizoaffective disorder, however, bipolar disorder recorded significantly, the highest employment rate. This supports a recent study that found that bipolar disorder uniquely predicted employment and independent living (Lee et al. 2015).

Disability Across the Disorders

In terms of disability, both schizophrenia and psychotic depression recorded the highest degree of disability as measured by the WHO-DAS. Similar observations were made in the Australian National Survey of Psychotic Disorders, where it was found that patients with affective psychoses were almost as disabled as those with schizophrenia (Gureje et al. 2002). However, schizoaffective disorder was somewhere between schizophrenia and affective psychosis in terms of disability, while patients with bipolar disorder were the least disabled. This is in contrast to a previous report indicating that patients with bipolar disorder experienced impairments similar to that of schizophrenia (Green 2006). However, our finding replicates a previous one in Nigeria (Adegbaju et al. 2013) that found bipolar disorder to be associated with a lower degree of disability compared with schizophrenia. This could have accounted for a relatively higher proportion of patients with bipolar in employment.

Demographic and Clinical Correlates of Disability Across the Disorders

We found that among respondents who were under 25 years of age, compared with the other groups, the level of disability was higher in schizophrenia, the trend was such that the level of disability reduced with increasing age. This is not unexpected given the likelihood of a relatively young age of onset of the illness within the age band. The association between schizophrenia occurring in adolescents and functional impairment has been well documented (Lay et al. 2000; Stentebjerg-Olesen et al. 2016). Although a previous study found older age to be associated with more severe disability in bipolar disorder (Arvilommi et al. 2015), our results did not confirm this. On the other hand, our findings regarding the older age group, corroborate previous ones that in depression, disability is more severe in the older age group (Rytsala et al. 2007), requiring more disability benefits (Holma et al. 2012).

In terms of gender, we found that the level of disability was higher in patients with schizophrenia who were of the male gender compared with patients in the other diagnostic groups who were also of male gender. Men were also significantly more disabled than women in schizophrenia. This finding lends support to the notion men living with schizophrenia significantly have more impairments in general domains of functioning than women (Olsson et al. 2016). On the other hand, among females, of the four groups, the highest level of disability was reported among patients with depression. This supports previous findings that in women, depression was associated with increased risk of disability than disability due to any other mental disorders (Mittendorfer-Rutz et al. 2014). By implication, men with depression would be less likely to suffer from significant disability compared with other types of severe mental disorders, a finding that our current study has demonstrated.

Another finding in this study was that, of the four mental disorders compared, the highest level of disability was reported among patients with schizophrenia despite being married. This could be because men living with schizophrenia were more likely to be married when compared with women (Olsson et al. 2016), and men in the schizophrenia group recorded significantly higher levels of disability than women in the current study.

We also found that of the four disorders compared, formal education was associated with low level of disability was in bipolar disorder. This may be expected, given observations that bipolar patients had no negative consequence for educational achievement and their educational level was comparably similar to that of the general population (Schoeyen et al. 2011). So also were bipolar patients, who were in employment most likely to report lower levels of disability. It has been reported that patients with bipolar disorder received disability benefits at par with those in the general population (Schoeyen et al. 2011). This implies that patients with bipolar disorder, compared to other psychotic disorders would suffer the lowest level of disability.

An interesting finding in the current study was that despite being in clinical remission, depression was associated with the highest level of disability of the four psychotic disorders compared. This implies that functional impairment that continued despite clinical remission observed in schizophrenia (Pinna et al. 2013) could be more severe in depression. Indeed, Nil and colleagues found that more than 50% of patients with depression demonstrated significant functional impairment after clinical remission had been achieved in them (Nil et al. 2016) and about two-thirds of patients with schizophrenia experience disabilities in the area of social roles, even when psychotic symptoms are in remission (Bellack et al. 2007).

We also noticed that although disability was higher across the four disorders among patients with young age of onset of illness, especially among those whose age of onset of illness was under 21 years, this was most marked in the depression group. This finding corroborates research reports that although early-onset schizophrenia is a severe disorder with a poor outcome, young people diagnosed with other psychotic disorders also have significant impairment likely to interfere with their maximal functional recovery (Starling et al. 2013).

In support of previously documented evidences (Misdrahi et al. 2012; Novick et al. 2015), we found that medication adherence was associated with lower levels of disability across the four disorders, which was most significant in patients with schizoaffective disorder and bipolar disorder.

Our findings suggest certain clinical and sociodemographic differences, yet overlapping boundaries among all these disorders. Our findings provide unique contributions to the ongoing debate on the nosology of severe mental disorders. To corroborate the similarities, the influential dopamine hypothesis in schizophrenia is also central to depression (Dunlop and Nemeroff 2007), and bipolar I disorder (Cousins et al. 2009), and dopamine receptor antagonists are useful in the treatment of both schizophrenia, schizoaffective disorder (Kane et al. 2002), and bipolar I disorder (Tohen et al. 2003).

Regression Analysis

The regression analyses bring a number of suggestions to the study; there were similarities and differing predictors of disability in psychosis. This is in support of the work of Gade (Gade et al. 2015). For example, young age at onset of illness is a common predictor of disability in schizophrenia and bipolar disorder, poor medication adherence in schizoaffective disorder and bipolar disorder, failure of symptom remission in schizoaffective disorder and depression, being unmarried also in schizoaffective disorder and depression and also high PANSS score in schizoaffective disorder and in depression. While female gender was predictive of disability in depression, reduced functioning (GAF) was a common predictor of disability in all the four groups.

Implications for Community Rehabilitation

These findings, have provided a useful contribution to the course these disorders. This has a number of implications in the area of their rehabilitation. The current study has demonstrated that medication adherence and symptom resolution do not equate prevention or improvement in social impairment. Thus, results of the current study underscore the need for early identification, prompt treatment, relapse prevention and rehabilitation of patients with psychosis. The tendency for clinicians to almost exclusively rely on medications with little or no psychosocial intervention has been criticized, this is because despite symptom reduction sequel to optimal pharmacological intervention, functional recovery may be poor (Leucht et al. 2009). The development of the revised version of the International Classification of Impairment, Disability and Handicaps (ICIDH) by the World Health Organization enables practitioners to view failure of functional recovery factoring the importance of environmental factors either as barriers or facilitators of recovery in people with disabilities from mental disorders (RÖSsler 2006).

Given cultural variations in presentation, symptomatology interpretation and treatment seeking (Gureje et al. 2005; Nguyen and Bornheimer 2014) in mental disorders, it is conceivable that disability from mental disorders may be influenced by culture. This is specifically relevant in the current study setting, Nigeria, where the pathway to mental health service is usually characterized by an initial use of alternative practitioners, including traditional healers and spiritualists (Lasebikan et al. 2012), and where is a high unmet need for those with mental disorders (Gureje and Lasebikan 2006) thereby leading to the majority of those seeking treatment for mental disorders present with disabilities (Gureje and Bamidele 1999).

Our findings also highlight the need for a policy driven effective and comprehensive system of psychiatric rehabilitation. As at the time of writing this report, Nigeria has no clear policy on the care of the mentally ill, including treatment of those who require long-term care (Coker et al. 2011). As suggested, psychiatric rehabilitation requires to be individually tailored (Bachrach 2000), and requires a lot of motivation from the patient (Corrigan et al. 2001). This may not be difficult to achieve in Nigeria, if prioritized, building on the strength of the extended family, social support system found in developing countries (Lasebikan et al. 2012). For example, over four decades ago, indigenous models of community based psychiatric rehabilitation such as “ARO” rehabilitation village system in Nigeria (Leighton et al. 1963), was developed, but as of today, the level of attention given to psychiatric rehabilitation in Nigeria is poor. Nigeria has the potential of developing an ecologically centered system of rehabilitation based on available and accessible local community resources such as the “Basic Needs” does in some other parts of Africa (Kigozi and Kinyanda 2006). This model runs within the context of the primary health care system. However, the implementation of a task-shifting strategy by training primary care workers in Nigeria, has demonstrated a feasible way of scaling up mental health services, including community rehabilitation in Nigeria (Gureje et al. 2015). A major drawback in this study is the definition of remission. Remission in depression is based on symptom resolution only and clinical experience suggests are occasions when there is discordance between patients’ symptom severity and level of functioning (Zimmerman et al. 2006). This implies the current symptom-based criteria for remission might be too narrow.

In this study, some other factors that have been reported to be associated with impairments in psychosis such as pre-morbid functioning, number of episodes and duration were not assessed. These offer some limitations to the results. Even though our sample was drawn from a general hospital population, we expect our results to reflect what would be expected in other clinical settings. The use of standardized instruments and diagnostic tools has enabled the results from this study to be based on clearly defined constructs.

Notes

Acknowledgements

We acknowledge all the members of our secretarial staff for their various supports.

Compliance with Ethical Standards

Conflict of interest

None.

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Copyright information

© Springer Science+Business Media New York 2016

Authors and Affiliations

  1. 1.Department of Psychiatry, College of MedicineUniversity of IbadanIbadanNigeria
  2. 2.Department of PsychiatryUniversity College HospitalIbadanNigeria

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