455
NeuroRehabilitation 34 (2014) 455–461 DOI:10.3233/NRE-141061 IOS Press
Cognitive dysfunction and functional limitations are associated with major depression in stroke survivors attending rehabilitation in Nigeria Akin Ojagbemia,∗ , Rufus Akinyemib and Olusegun Baiyewua a Department b Division
of Psychiatry, College of Medicine, University of Ibadan, Ibadan, Nigeria of Neurology, Department of Medicine, Federal Medical Centre, Abeokuta, Nigeria
Abstract. BACKGROUND: The frequency and predictors of post-stroke depression diagnosed according to codified criteria remain unknown in Nigeria. OBJECTIVES: We report on the predictors of post-stroke major depressive disorder (MDD) in Nigeria using standardized assessment methods. METHOD: Using a case-control design, we consecutively recruited 260 participants. Among them were 130 stroke survivors attending rehabilitation. Along with historical details, an exploration for MDD meeting criteria in the fourth edition of the Diagnostic and Statistical Manual of Mental Disorders was carried out using a semi-structured interview. Cognition was assessed using both the Mini Mental State Examination and the modified Indiana University Token test, while disability was assessed using the modified Rankin Scale. Associations were explored using univariate and multivariate analyses. RESULTS: The diagnosis of MDD was more frequently present in the stroke survivors (41.5%, p < 0.001). It was strongly associated with female gender (p < 0.001, O.R = 3.77, 95% C.I = 1.78–8.00), disability (p = 0.001, O.R = 3.27, 95% C.I = 1.57–6.83), and cognitive dysfunction (p < 0.001, O.R = 5.28, 95% C.I = 2.25–12.41). Female gender (p = 0.037, O.R = 2.65, 95% C.I = 1.06–6.62) and cognitive dysfunction (P = 0.03, O.R = 4.58, 95% C.I = 1.68–12.46) were independent predictors of post-stroke MDD. CONCLUSION: Post stroke MDD is common in Nigerian survivors attending rehabilitation. The high rates reported in this population may be the result of factors affecting the efficient management of stroke in developing countries. Keywords: Stroke, survivors, depression, DSM IV, rehabilitation, disability, cognition
1. Introduction Stroke is a growing public health problem all over the world. It is the most common cause of medical deaths in Nigeria (Owolabi et al., 2010). Improvement in the management of stroke related complications have led to a gradual, continuous decline in mortality. ∗ Address for correspondence: Akin Ojagbemi, Department of Psychiatry, College of Medicine, University of Ibadan, P.M.B, 5017 (GPO), Ibadan, Nigeria. Tel.: +234 8036737171; E-mail: drakinja [email protected].
But this success has paradoxically resulted in increasing number of survivors left with physical and mental impairments as well as disabilities (Lishman, 2005; Owolabi, 2008). Much of this morbidity results from depression (Paolucci, 2008; Bilge et al., 2008; Schmid et al., 2011). The reported frequency of post-stroke depression from previous studies in Nigeria and other parts of the world ranges from 20% to 65% (Fatoye et al., 2009; Oladiji et al., 2009; Scmid et al., 2011). This wide range in the rates may be the result of several methodological
1053-8135/14/$27.50 © 2014 – IOS Press and the authors. All rights reserved
456
A. Ojagbemi et al. / Post-stroke major depression in Nigeria
differences. One important variation between studies is in the definition of post-stroke depression. It may be more clinically meaningful to define depression according to codified criteria such as those in the evidence based Diagnostic and Statistical Manual of Mental Disorders (DSM) (American Psychiatric Association, 1994) or the International Classification of Diseases (World Health Organization, 1992). Post-stroke depression is sometimes reported to be a psychological reaction to physical disability and the psycho-social stress surrounding the stroke event (Robinson, 2003; Fatoye et al., 2009). Other reports have also suggested that depression results from subclinical brain injuries (Alexopoulos et al., 1997; Mast et al., 2004). It is known to be one of the more readily treatable complications of stroke (Saxena et al., 2007; Jorge et al., 2010). But it may remain un-recognized except it is purposively searched for (Paolucci, 2003; Hackett et al., 2005; Dafer et al., 2008). It may also remain untreated in cases where it is apparent because of the general opinion that depression is an inevitable psychological reaction to disability, and as such should improve when the patients’ physical condition improves. Early recognition and treatment of depression in stroke patients through identification of its risk factors should improve the effort at stroke rehabilitation. Previous published reports of depression after stroke in Nigeria have relied on the older depression inventories (Fatoye et al., 2009) or rating scales (Oladiji et al., 2009) for the assessment of depression symptomatology. Yet the frequency and predictors of post-stroke major depression diagnosed according to codified criteria remain unknown in the country setting. The present study seeks to determine the frequency and predictors of Major depressive disorder (MDD) diagnosed according to DSM IV criteria in a cohort of Nigerian stroke survivors attending rehabilitation using standardized assessments.
2. Method 2.1. Subjects The study population comprised of 130 stroke survivors who were consecutively recruited from the physiotherapy clinics at the University College Hospital, Ibadan, and the Federal Medical Centre, Abeokuta. They had been referred by their primary physicians. Both locations are in south-Western Nigeria. The study
was conducted over a 6 months period between May and October 2010. The diagnosis of stroke was made in conformity with World Health Organisation (WHO) criteria (World Health Organization, 1988). Demographic data, personal, psychiatric, medical, and family history were obtained from all participants. They also underwent full physical examination. Stroke survivors in this study were those who had their index stroke between three months and two years before recruitment into the study. Survivors with a history of recurrent stroke or dementia diagnosed before the stroke event were excluded. This was based on informant reports. Also excluded were those with surgically treatable lesions on CT-scan (e.g. brain tumours), other central nervous system (CNS) conditions that can cause depression (e.g. Parkinson’s disease), severe co-morbidity (e.g. chronic kidney disease), as well as previous history of psychiatric disturbances. Survivors who were unable to communicate reliably (because of aphasia) were additionally excluded from the study. A control group of 130 apparently normal subjects matched for age, sex, and level of education were also recruited. They consisted of volunteering spouses or unrelated caregivers of patients attending the physiotherapy clinic at the two study locations. Communal living and support is common in the cultural setting of this study. As such, clinic attendees are frequently accompanied by their spouses, relations, friends, neighbours or domestic staff. They all provide the patients with ongoing emotional support, and help ensure compliance with treatment. Informed consent was obtained from all subjects. The study received ethical approval from the Health Research Ethical Committees of the University College Hospital/ University of Ibadan and the Federal Medical Centre, Abeokuta. 2.2. Assessment for depression Depression diagnosis was made using the Schedules for Clinical Assessment in Neuropsychiatry (SCAN) (World Health Organization, 1999). The SCAN is a semi-structured standardized clinical interview. Rating is done on the basis of matching the answers of the respondent against the definition of the symptoms in a glossary which is an integral part of the instrument. The SCAN provides a diagnosis compatible with the DSM IV (American Psychiatry Association, 1994) or ICD 10 (World Health Organization, 1992). For the purpose of this study, the diagnosis of MDD was generated manually according to the DSM IV criteria. In this regard, the
A. Ojagbemi et al. / Post-stroke major depression in Nigeria
diagnosis was made when a stroke survivor had at least five symptoms of depression occurring persistently for two weeks or more. These symptoms must include either depressed mood or anhedonia, or both, and must have caused substantial distress or impairments in the individual (American Psychiatric Association, 1994). 2.3. Functional disability Functional disability was assessed using the modified Rankin Scale (mRS). The mRS is a clinician-reported measure of global disability. It does not provide a comprehensive assessment of basic and instrumental Activities of Daily Living (ADL), but correlates with measures doing so (Cup et al., 2003; Kwon et al., 2004). The mRS also exhibits a strong relationship with clinical measurements of stroke severity (Banks et al., 2007; Owolabi & Platz, 2008). It includes five degrees of disability, ranging from slight, to severe disability. The mRS has been validated for use among Yoruba Nigerians who predominate the study population (Owolabi et al., 2007). 2.4. Cognitive assessment instruments Cognitive assessment was done using both the modified Indiana University Token test (Token test) (De Renzi & Vignolo, 1962) and the modified Mini Mental State Examination (M.M.S.E) (Folstein et al., 1975). For the purpose of this study, the M.M.S.E was chosen as a measure of global cognitive function, while the Token test was selected as a measure of executive function. Normative data had been established for elderly Yoruba Nigerians who are subjects in the Ibadan-Indianapolis dementia project, a large scale longitudinal, prospective community based study of dementia in Ibadan and Indianapolis (Hendrie et al., 2001).
categorical variables included proportions for binary data and the number and frequency in each category. Chi Square was used to test the difference between groups. Student t-test was used to find the difference between means. A logistic regression analysis was done to determine odd ratios. This was followed by a multivariate regression with MDD as the dependent variable. Values of p < 0.05 were considered statistically significant. Data were analyzed using the Statistical Package for the Social Sciences version 15.0 [SPSS inc].
3. Results 3.1. Characteristics of subjects The characteristics of stroke survivors are shown on Tables 1 and 2. There were 60 male and 70 female survivors. They had a mean age of 59.5 (±11.1) years. Twenty six had no formal education, while the remaining had up to 6 years of formal education. Over half of the survivors had weaknesses on the left side of the body. Background medical illnesses were present in all the survivors. The most common co-morbidity with stroke was systemic hypertension. Over three quarter of the stroke survivors were using prescribed medications for the various co-morbid conditions, and about two in five had a family history of hypertension, diabetes or stroke. Also, nearly one quarter was either a current or a former user of alcohol. A majority of the survivors had significant psychosocial stress in the one year before recruitment into the study. Ninety one (70%) controls were spouses of patients while the remaining 39 were neighbours, friends or domestic assistants. Table 1 Characteristics of stroke survivors and controls Characteristics
2.5. Psychosocial stressors In this study, psychosocial stressors referred to the presence of significant life events different from the stroke, adjudged by the survivor as having adverse consequences on his/her life. 2.6. Data management and analysis Descriptive statistics were calculated for all variables. For continuous variables, means, and standard deviations were calculated. Descriptive statistics for
457
Gender (%) Male Females Education (%) 0 years 6 years >6 years Diagnosis MDD Depressive Symptoms Non-Depressed Cognitive Dysfunction (%) MMSE Token Test
Stroke
Controls
46.2 53.9
48.5 51.5
20.0 13.1 66.9
20.8 17.7 61.6
54 (41.5) 27 (20.8) 49 (37.7)
18 (13.9) 17 (13.1) 95 (73.1)
34 (26.2) 101 (77.69)
22 (16.9) 70 (53.85)
p-value 0.960
0.150
NeuroRehabilitation 34 (2014) 455–461 DOI:10.3233/NRE-141061 IOS Press
Cognitive dysfunction and functional limitations are associated with major depression in stroke survivors attending rehabilitation in Nigeria Akin Ojagbemia,∗ , Rufus Akinyemib and Olusegun Baiyewua a Department b Division
of Psychiatry, College of Medicine, University of Ibadan, Ibadan, Nigeria of Neurology, Department of Medicine, Federal Medical Centre, Abeokuta, Nigeria
Abstract. BACKGROUND: The frequency and predictors of post-stroke depression diagnosed according to codified criteria remain unknown in Nigeria. OBJECTIVES: We report on the predictors of post-stroke major depressive disorder (MDD) in Nigeria using standardized assessment methods. METHOD: Using a case-control design, we consecutively recruited 260 participants. Among them were 130 stroke survivors attending rehabilitation. Along with historical details, an exploration for MDD meeting criteria in the fourth edition of the Diagnostic and Statistical Manual of Mental Disorders was carried out using a semi-structured interview. Cognition was assessed using both the Mini Mental State Examination and the modified Indiana University Token test, while disability was assessed using the modified Rankin Scale. Associations were explored using univariate and multivariate analyses. RESULTS: The diagnosis of MDD was more frequently present in the stroke survivors (41.5%, p < 0.001). It was strongly associated with female gender (p < 0.001, O.R = 3.77, 95% C.I = 1.78–8.00), disability (p = 0.001, O.R = 3.27, 95% C.I = 1.57–6.83), and cognitive dysfunction (p < 0.001, O.R = 5.28, 95% C.I = 2.25–12.41). Female gender (p = 0.037, O.R = 2.65, 95% C.I = 1.06–6.62) and cognitive dysfunction (P = 0.03, O.R = 4.58, 95% C.I = 1.68–12.46) were independent predictors of post-stroke MDD. CONCLUSION: Post stroke MDD is common in Nigerian survivors attending rehabilitation. The high rates reported in this population may be the result of factors affecting the efficient management of stroke in developing countries. Keywords: Stroke, survivors, depression, DSM IV, rehabilitation, disability, cognition
1. Introduction Stroke is a growing public health problem all over the world. It is the most common cause of medical deaths in Nigeria (Owolabi et al., 2010). Improvement in the management of stroke related complications have led to a gradual, continuous decline in mortality. ∗ Address for correspondence: Akin Ojagbemi, Department of Psychiatry, College of Medicine, University of Ibadan, P.M.B, 5017 (GPO), Ibadan, Nigeria. Tel.: +234 8036737171; E-mail: drakinja [email protected].
But this success has paradoxically resulted in increasing number of survivors left with physical and mental impairments as well as disabilities (Lishman, 2005; Owolabi, 2008). Much of this morbidity results from depression (Paolucci, 2008; Bilge et al., 2008; Schmid et al., 2011). The reported frequency of post-stroke depression from previous studies in Nigeria and other parts of the world ranges from 20% to 65% (Fatoye et al., 2009; Oladiji et al., 2009; Scmid et al., 2011). This wide range in the rates may be the result of several methodological
1053-8135/14/$27.50 © 2014 – IOS Press and the authors. All rights reserved
456
A. Ojagbemi et al. / Post-stroke major depression in Nigeria
differences. One important variation between studies is in the definition of post-stroke depression. It may be more clinically meaningful to define depression according to codified criteria such as those in the evidence based Diagnostic and Statistical Manual of Mental Disorders (DSM) (American Psychiatric Association, 1994) or the International Classification of Diseases (World Health Organization, 1992). Post-stroke depression is sometimes reported to be a psychological reaction to physical disability and the psycho-social stress surrounding the stroke event (Robinson, 2003; Fatoye et al., 2009). Other reports have also suggested that depression results from subclinical brain injuries (Alexopoulos et al., 1997; Mast et al., 2004). It is known to be one of the more readily treatable complications of stroke (Saxena et al., 2007; Jorge et al., 2010). But it may remain un-recognized except it is purposively searched for (Paolucci, 2003; Hackett et al., 2005; Dafer et al., 2008). It may also remain untreated in cases where it is apparent because of the general opinion that depression is an inevitable psychological reaction to disability, and as such should improve when the patients’ physical condition improves. Early recognition and treatment of depression in stroke patients through identification of its risk factors should improve the effort at stroke rehabilitation. Previous published reports of depression after stroke in Nigeria have relied on the older depression inventories (Fatoye et al., 2009) or rating scales (Oladiji et al., 2009) for the assessment of depression symptomatology. Yet the frequency and predictors of post-stroke major depression diagnosed according to codified criteria remain unknown in the country setting. The present study seeks to determine the frequency and predictors of Major depressive disorder (MDD) diagnosed according to DSM IV criteria in a cohort of Nigerian stroke survivors attending rehabilitation using standardized assessments.
2. Method 2.1. Subjects The study population comprised of 130 stroke survivors who were consecutively recruited from the physiotherapy clinics at the University College Hospital, Ibadan, and the Federal Medical Centre, Abeokuta. They had been referred by their primary physicians. Both locations are in south-Western Nigeria. The study
was conducted over a 6 months period between May and October 2010. The diagnosis of stroke was made in conformity with World Health Organisation (WHO) criteria (World Health Organization, 1988). Demographic data, personal, psychiatric, medical, and family history were obtained from all participants. They also underwent full physical examination. Stroke survivors in this study were those who had their index stroke between three months and two years before recruitment into the study. Survivors with a history of recurrent stroke or dementia diagnosed before the stroke event were excluded. This was based on informant reports. Also excluded were those with surgically treatable lesions on CT-scan (e.g. brain tumours), other central nervous system (CNS) conditions that can cause depression (e.g. Parkinson’s disease), severe co-morbidity (e.g. chronic kidney disease), as well as previous history of psychiatric disturbances. Survivors who were unable to communicate reliably (because of aphasia) were additionally excluded from the study. A control group of 130 apparently normal subjects matched for age, sex, and level of education were also recruited. They consisted of volunteering spouses or unrelated caregivers of patients attending the physiotherapy clinic at the two study locations. Communal living and support is common in the cultural setting of this study. As such, clinic attendees are frequently accompanied by their spouses, relations, friends, neighbours or domestic staff. They all provide the patients with ongoing emotional support, and help ensure compliance with treatment. Informed consent was obtained from all subjects. The study received ethical approval from the Health Research Ethical Committees of the University College Hospital/ University of Ibadan and the Federal Medical Centre, Abeokuta. 2.2. Assessment for depression Depression diagnosis was made using the Schedules for Clinical Assessment in Neuropsychiatry (SCAN) (World Health Organization, 1999). The SCAN is a semi-structured standardized clinical interview. Rating is done on the basis of matching the answers of the respondent against the definition of the symptoms in a glossary which is an integral part of the instrument. The SCAN provides a diagnosis compatible with the DSM IV (American Psychiatry Association, 1994) or ICD 10 (World Health Organization, 1992). For the purpose of this study, the diagnosis of MDD was generated manually according to the DSM IV criteria. In this regard, the
A. Ojagbemi et al. / Post-stroke major depression in Nigeria
diagnosis was made when a stroke survivor had at least five symptoms of depression occurring persistently for two weeks or more. These symptoms must include either depressed mood or anhedonia, or both, and must have caused substantial distress or impairments in the individual (American Psychiatric Association, 1994). 2.3. Functional disability Functional disability was assessed using the modified Rankin Scale (mRS). The mRS is a clinician-reported measure of global disability. It does not provide a comprehensive assessment of basic and instrumental Activities of Daily Living (ADL), but correlates with measures doing so (Cup et al., 2003; Kwon et al., 2004). The mRS also exhibits a strong relationship with clinical measurements of stroke severity (Banks et al., 2007; Owolabi & Platz, 2008). It includes five degrees of disability, ranging from slight, to severe disability. The mRS has been validated for use among Yoruba Nigerians who predominate the study population (Owolabi et al., 2007). 2.4. Cognitive assessment instruments Cognitive assessment was done using both the modified Indiana University Token test (Token test) (De Renzi & Vignolo, 1962) and the modified Mini Mental State Examination (M.M.S.E) (Folstein et al., 1975). For the purpose of this study, the M.M.S.E was chosen as a measure of global cognitive function, while the Token test was selected as a measure of executive function. Normative data had been established for elderly Yoruba Nigerians who are subjects in the Ibadan-Indianapolis dementia project, a large scale longitudinal, prospective community based study of dementia in Ibadan and Indianapolis (Hendrie et al., 2001).
categorical variables included proportions for binary data and the number and frequency in each category. Chi Square was used to test the difference between groups. Student t-test was used to find the difference between means. A logistic regression analysis was done to determine odd ratios. This was followed by a multivariate regression with MDD as the dependent variable. Values of p < 0.05 were considered statistically significant. Data were analyzed using the Statistical Package for the Social Sciences version 15.0 [SPSS inc].
3. Results 3.1. Characteristics of subjects The characteristics of stroke survivors are shown on Tables 1 and 2. There were 60 male and 70 female survivors. They had a mean age of 59.5 (±11.1) years. Twenty six had no formal education, while the remaining had up to 6 years of formal education. Over half of the survivors had weaknesses on the left side of the body. Background medical illnesses were present in all the survivors. The most common co-morbidity with stroke was systemic hypertension. Over three quarter of the stroke survivors were using prescribed medications for the various co-morbid conditions, and about two in five had a family history of hypertension, diabetes or stroke. Also, nearly one quarter was either a current or a former user of alcohol. A majority of the survivors had significant psychosocial stress in the one year before recruitment into the study. Ninety one (70%) controls were spouses of patients while the remaining 39 were neighbours, friends or domestic assistants. Table 1 Characteristics of stroke survivors and controls Characteristics
2.5. Psychosocial stressors In this study, psychosocial stressors referred to the presence of significant life events different from the stroke, adjudged by the survivor as having adverse consequences on his/her life. 2.6. Data management and analysis Descriptive statistics were calculated for all variables. For continuous variables, means, and standard deviations were calculated. Descriptive statistics for
457
Gender (%) Male Females Education (%) 0 years 6 years >6 years Diagnosis MDD Depressive Symptoms Non-Depressed Cognitive Dysfunction (%) MMSE Token Test
Stroke
Controls
46.2 53.9
48.5 51.5
20.0 13.1 66.9
20.8 17.7 61.6
54 (41.5) 27 (20.8) 49 (37.7)
18 (13.9) 17 (13.1) 95 (73.1)
34 (26.2) 101 (77.69)
22 (16.9) 70 (53.85)
p-value 0.960
0.150
