Research Article, Int J Ment Health Psychiatry Vol: 3 Issue: 4
The Quality of Sleep, Burden of Care and Psychological Distress in Caregivers of Patients with Stroke
*Corresponding Author : Abosede Adekeji Adegbohun
Federal Neuro-Psychiatric Hospital Yaba, 8, Harvey Road, PMB 2008, Yaba, Lagos, Nigeria
E-mail: [email protected]
Received: September 19, 2017 Accepted: October 16, 2017 Published: October 21, 2017
Citation: Adegbohun AA, Uwakwe R, Adeosun II, Ojini FI (2017) The Quality of Sleep, Burden of Care and Psychological Distress in Caregivers of Patients with Stroke. Int J Ment Health Psychiatry 3:4. doi: 10.4172/2471-4372.1000150
Caring for patients with chronic medical disorders such as stroke is a very demanding task. Family caregivers suffer various negative health consequences in the course of rendering care for patients with stroke. There is paucity of research on the impact of caregiving on the quality of sleep of these caregivers.
Aim: To assess the quality of sleep in caregivers of patients with stroke attending a tertiary teaching hospital in Lagos Nigeria. Also, to determine the factors associated with poor quality of sleep in the caregivers. The study also determined the relationship between quality of sleep, burden of care and psychological distress among the caregivers.
Study design: Cross-sectional study.
Methodology: Sixty-four informal caregivers of randomly selected patients with stroke attending the Medical Out-patients clinic of the Lagos University Teaching Hospital Idi-Araba, Lagos, South-Western, Nigeria. The quality of sleep of the participants was assessed using the Pittsburgh Sleep Quality Index (PSQI). Caregivers’ burden and psychological distress were assessed with Zarit Burden Interview (ZBI) and General Health Questionnaire-12 (GHQ-12) respectively. Data were obtained from all the participants via a face to face interview conducted by the researchers; additional clinical variables pertaining to the illness in the patients were obtained from the patients’ case files.
Results: About 31.3% of the caregivers of patients with stroke had poor quality of sleep (global PSQI score > 5). On regression analysis, caregivers’ burden (p=0.004) and psychological distress in the caregivers (p=0.004) are the only factors that were independently associated with poor quality of sleep among the caregivers.
Conclusion: Our findings bring to the fore the need to screen caregivers of patients with stroke for sleep problems and facilitate their access to relevant interventions.
Keywords: Caregivers; Stroke; Quality of sleep; Pittsburgh Sleep Quality Index (PSQI); Burden of care; Psychological distress
PSQI: Pittsburgh Sleep Quality Index; ZBI: Zarit Burden Interview; GHQ-12: General Health Questionnaire-12
Stroke or “brain attack” is an acute central nervous system injury that results in neurologic symptoms and signs brought on by a reduction or absence of perfusion to a territory of the brain . The disruption in flow is from either an occlusion (ischemic) or rupture (hemorrhagic) of the blood vessel. It is a chronic medical disorder that accounts for a wide degree of morbidity causing gross physical impairment and mortality . It is one of the leading causes of disability and accounts for about 3.4% of worldwide disability adjusted life years . The current prevalence of stroke in Nigeria is 1.14 per 1000 with 30 days case fatality rate as high as 40% . The disability suffered by these patients affects different domains of their lives. Thus, they may need assistance from others for their day to day activities. Caregivers help patients with stroke with activities of daily living and also assist them in the areas of mobility and support . Most of these patients are often cared for by family members who often provide them with the needed care [5-7]. Caregivers experience great degree of burden in providing the required care; they spend much of their quality time especially, waking up during the night to care for the patients. The disruptions in the caregivers’ sleep may as well be an aftermath of sleep disturbances common among patients with stroke. They may subsequently suffer detrimental consequences such as poor quality of sleep, significant burden and psychological distress.
Sleep is an important phenomenon and attribute of every human with its characteristics phases. Sleep plays important functions with respect to physical and psychological restoration, memory and emotional regulation in human . Difficulty at defining quality of sleep across the literature has been identified, majority have viewed it as the ability of a person to have uninterrupted sleep with relatively good ability to initiate sleep . Poor quality of sleep has grievous consequences especially among caregivers of persons with chronic disorders as it tends to impact significantly on their care-giving role [10,11]. There is paucity of research on the impact of care-giving on the quality of sleep of caregivers of patients with stroke in Sub- Saharan Africa. To the best of our knowledge, this is the first study that assessed the quality of sleep of caregivers of patients with stroke in relation to burden and psychological distress in our cultural setting.
Materials and Methods
The study was conducted at the Medical outpatient clinic of Lagos University Teaching Hospital, Idi-Araba, Lagos, South- Western, Nigeria. The hospital is a multi-specialist teaching hospital which has capacity for both in-patient and outpatient care. Patients with stroke and all other neurological diagnoses are attended to at both the outpatient and in-patient facilities of the hospital as might be indicated. On a weekly basis about 100 patients with different neurological diagnoses are seen at the outpatient clinic. Of these, stroke cases constitute about 45% of all neurological cases.
The informal caregivers (n=64) of randomly selected patients with stroke were recruited into the study between July and December, 2013. To be recruited into the study, the diagnosis of stroke in the patient must have been confirmed clinically and with the aid of radiological investigations by the consultant neurologist. The informal caregiver must have been caring for the patient for at least 6 months and should not be providing care for another person or persons with other chronic mental or physical conditions besides the patient with stroke. Caregivers with a past history of medical or mental illness with onset antedating the uptake of the care-giving role and those that were paid caregivers were excluded from the study. Also excluded from the study were caregivers who could not be interviewed in English.
The approval for the study was obtained from the Ethical and Review Committee of the Lagos University Teaching Hospital, Idi-Araba. Permission was also obtained from all the consultant neurologists whose patients participated in the study. Caregivers of randomly selected patients with confirmed diagnosis of stroke as documented by the consultant neurologists who met the inclusion criteria for the study were selected over the study period after obtaining their consent. Face to face interview was used to obtain data from the participants by the researchers; additional clinical variables pertaining to the illness in the patients were obtained from the patients’ case files. The participants were assessed with the instruments listed.
Pittsburgh Sleep Quality Index (PSQI): It is a self-rated questionnaire that assesses sleep quality and sleep disturbances over a one month period . It is made up of 19 self-rated questions and five bed partner or roommate rated questions. The 19 self-rated items are combined to form seven “components” comprising of subjective sleep quality, sleep latency, sleep duration, habitual sleep efficiency, sleep disturbances, use of sleeping medication, and daytime dysfunction. Only these 19 items are used in scoring the instrument; each of the 7 “component scores” has a range of 0-3 points: 0 indicates no difficulty, 1 indicates mild difficulty, 2 indicates moderate difficulty and 3 indicates severe difficulty.
The sum of the scores for the seven components yields one “global” score, with a range of 0-21 points. “0” means no difficulty and 21 shows severe difficulties in all areas. The instrument has a diagnostic sensitivity and specificity in distinguishing good and poor sleepers . A global PSQI score of greater than 5 shows that the individual is a “poor sleeper”. The instrument has been used widely in different cultural settings. It was validated in Nigeria  who reported the specificity as 54.5% and sensitivity as 72.0% in this cultural setting.
Zarit Burden Interview (ZBI): This is a 22 item selfadministered questionnaire that measures burden in different areas including physical and psychological health, social isolation and the relationship between the caregiver and the patient. There are 5 item responses which range from 0 to 4 and are scored as 0=never, 1=rarely, 2=sometimes, 3=quite frequently and 4=nearly always. The rating of the sum of the points gives the severity of the burden experienced by the caregiver. A score between 0 to 20 shows little or no burden, a score of 21 to 40 indicates mild to moderate burden, 41 to 60 indicates moderates to severe burden while a score of 61 to 88 shows severe burden . The instrument has been used widely in different population and has been previously used in Nigeria .
The General Health Questionnaire -12 (GHQ-12): This is a selfadministered questionnaire consisting of 12 items that was designed by David Goldberg to measure emotional wellbeing, psychological distress and to detect current non psychotic psychiatric disorders in primary care, general medical practice or community survey. Its use as a screening instrument has been well documented [17-19]. The responses are given on a 4 point scale and scored with a binary method (0-0-1-1). Each respondent obtains a score that ranges from 0 (the minimum score) to 12 (the maximum score). A score of 3 or more shows significant psychiatric morbidity and the individual who has such score is operationally defined as “psychiatric case”. It has been used globally and in Nigeria with good documented reliability and validity scores .
Semi-structured questionnaire (For patient participants): This was designed to elicit the socio-demographic characteristics and appropriate clinical variables of the patients. These included the patient’s age, gender, marital status, religion, ethnicity, highest level of formal education, current employment status. It also included illness related variables in the patient such as duration of illness, age of onset, number of episodes/hospital admission. Supplementary information about these variables was obtained from the clinical records.
Semi-structured questionnaire (For the caregiver participants): This was designed to elicit the socio-demographic characteristics of the caregivers. The participant’s age, gender, marital status, religion, ethnicity, highest level of formal education, current employment status, duration of providing care to the care recipients were included. It also included amount spent on the care recipient’s treatment monthly and sources of finance.
Data were analysed with IBM-SPSS version 20 . The primary outcome variable was quality of sleep. Relationship between dependent variables and continuous variables were determined using correlation analysis while the relationship between dependent variables and categorical variables were determined with student t-test or its non-parametric equivalent as appropriate.
Using the global PSQI as the dependent variable, the independent variables were entered into a stepwise multiple regression analysis in the following sequence: caregivers and patients socio-demographic characteristics, clinical characteristics of patients with stroke, ZBI and GHQ-12 scores. Multi-collinearity checks were made by assessing correlation coefficients of independent variables with one another, and the values of “tolerance” and variance inflation factor (VIF). All tests were two tailed with significance level (p), set at 0.05.
Socio-demographic characteristics of the participants
The sample consisted of 64 randomly selected informal caregivers of patients with stroke. The mean age of the caregivers of patients with stroke was 41.56 (±15.25) years (Table 1). More than half (53.1%) of the caregivers of patients with stroke were females. About 6 out 10 of the caregivers were married (60.9%) and attained tertiary level of education (64.1%) respectively while about 56.3% were of the Yoruba ethnic group. The mean age of the patients with stroke was 61.05 (±11.91) years. There were more males (62.5%) than females, 7 out of 10 patients were married (73.4%) and were either retired or unemployed (70.3%) respectively, and nearly half (48.4%) of them attained tertiary level of education. The age of onset of stroke episode was 57.0 (±11.07) years, and the median duration of illness was 24 months.
|Age in years
Table 1: Socio-demographic characteristics of the study participants.
Pattern of Quality of Sleep in the participants
The scores of the participants on each of the seven components of the PSQI and their global PSQI scores are highlighted in Table 2. The mean duration of sleep in the caregivers was 6.44 (±1.61) hours. The mean subjective sleep quality was 0.59 (±0.75), mean sleep latency score was 0.73 (±0.96), habitual sleep efficiency was 0.42 (±0.77), sleep disturbances was 1.03 (±0.47) and daytime dysfunction score of 0.48 (±0.64). The global PSQI scores among the caregivers ranged from 1 to 12 with a mean score of 4.52 (±3.52) and median score of 3.0 respectively. Using the standardized global PSQI score of greater than 5 as cut off for poor quality of sleep; about 31.3% of the caregivers of patients with stroke had poor quality of sleep.
|Variable||Mean ( ± SD)|
|Subjective sleep quality (component1)||0.59 ( ± 0.75)|
|Sleep latency (component 2)||0.73 ( ± 0.96)|
|Sleep duration in hours (component 3)||6.44 ( ± 1.61)|
|Habitual sleep efficiency (component 4)||0.42 ( ± 0.77)|
|Sleep disturbances (component 5)||1.03 ( ± 0.47)|
|Use of sleep medicine (component 6)||0.19 ( ± 0.53)|
|Daytime dysfunction (component 7)||0.48 ( ± 0.64)|
|Global PSQI score||4.52 ( ± 3.52)|
Table 2: The patterns of quality of sleep in the participant, N=64.
The relationship between quality of sleep, burden of care and psychological distress among caregivers of patients with stroke
There was significant positive correlation between poor quality of sleep and high level of burden of care in the caregivers (r=0.573, p<0.001). That is caregivers who had poor quality of sleep had significantly higher level of burden (Table 3). There was also significant positive correlation between poor quality of sleep and higher GHQ-12 scores (r=0.619, p<0.001) among the caregivers. Participants who had poor quality of sleep had significantly higher level of psychological distress.
|Burden (ZBI)||0.573r*||< 0.001|
|Psychological distress (GHQ-12)||0.619r*||<0.001|
Significant p value in bold font
Table 3: Relationship between quality of sleep, burden of care and psychological distress among the caregivers of patients with stroke, Global PSQI score, N=64.
Factors associated with Quality of Sleep
Primary caregivers had significantly poorer quality of sleep than those who were not primary caregivers (t=3.063, p=0.003) (Table 4). There was however no significant association between quality of sleep and age of the caregivers (r=0.191, p=0.064), age of the patients (r=- 0.166, p=0.179) and age at onset of stroke illness (r=-0.128, p=0.312). Similarly, there was no significant relationship between quality of sleep and caregiver’s gender (t=-0.529, p=0.599), employment status (t=-1.150, p=0.268), educational level (t =4.575, p= 0.052), caregivers’ use of alcohol (t=0.963, p=0.340) and coffee use by the caregivers (t=0.606, p=0.547).
|Mean ( ± SD)||Statistics||P value|
|Primary caregiver||5.22 ± 3.70||t= 3.063||p = 0.003|
|Others||2.84 ± 2.39|
|Male||4.27 ± 3.65||t= -0.529||p = 0.599|
|Female||4.74 ± 3.44|
|Employed||4.22 ± 3.26||t= -1.150||p=0.268|
|Not employed||5.69 ± 4.33|
|≤Secondary||5.65 ± 3.86||t=4.575||p= 0.052|
|Tertiary||3.88 ± 3.19|
|Duration of care-giving||- 0.034||0.789|
|Age of patients||-0.166r*||0.179|
|Age at onset of illness||-0.128r*||0.312|
|Age of caregiver||0.191r*||0.064|
t= independent sample T-test
Significant p value in bold font
Table 4: Factors associated with quality of sleep, N=64.
On regression analysis (Table 5), caregivers’ burden (β=0.393, p=0.004) and psychological distress (β=0.377, p=0.004) were independently associated with poor quality of sleep among the participants. The independent variable in the model accounted for 45.2% (R2 variance=0.452) of the variability in the caregiver’s quality of sleep. The total ZBI had the highest t-value and standardised coefficient, indicating a relatively greater importance in predicting poor quality of sleep in caregivers of patients with stroke than the other variables assessed.
|un standardized coeff*||stand coff|
un-standardized coeff*= un-standardized coefficient
Stand coeff= standardized coefficient
Significant p value in bold font
CI= confidence interval
Table 5: Predictors of poor quality of sleep on regression analysis, N=64.
To the best of our knowledge, this study is the first to assess the quality of sleep in caregivers of patients with stroke in relation to caregivers’ burden and psychological distress in the caregivers in Sub Saharan Africa. We found that 31.3% of the caregivers had poor quality of sleep (PSQI score>5). This result is consistent with similar study by Ilse et al among caregivers of patients with stroke in Belgium who reported that 21% to 33% of the caregivers had poor quality of sleep . The prevalence however differed from was reported in a pilot study conducted among caregivers of patients with stroke in USA  where two thirds of the caregivers were reported to have poor quality of sleep. The higher prevalence reported in the latter study may be due to the relatively small number of participants where only 29 female caregivers took part in the study. Similarly, despite the use of same PSQI to assess poor quality of sleep in caregivers, this study found a lower prevalence of poor quality of sleep among the caregivers of patients with stroke in comparison to studies done among caregivers of patients with secondary progressive multiple sclerosis and end-stage renal disease on hemodialysis with reported prevalence of 54.3% and 73.9% respectively [22,23]. The observed variation may be due to the difference in the impact of a more severe disease on the caregivers. These caregivers cared for patients who had apparently severe disorders compared to the current study.
The mean ages of the caregivers of patients with stroke in this study was 41.45 ± 15.25 years. The reported mean age is similar to that reported in South India by . This age group constitute the productive work force of the society. Their involvement in the care of the patients may worsen their productivity at work with negative economic consequences for the individual, their family and the nation. They may have to take time off work, may arrive late or leave early from work as a result of the care-giving. More than half (53.1) of the caregivers were females, a finding consistent with previous study among caregivers of patients with stroke . In the Sub-Saharan African regions, females were more likely to take up the role of caring for persons with chronic disorders. The care for dependent family members has long been assumed as the primary responsibilities of women. They were more likely to be the sole primary caregivers and the patients’ spouses as replicated in this study . It is therefore surprising that poor quality of sleep among the caregivers was not significantly associated with gender in this study. The reported finding may be partly explained by tendency for increased afternoon naps among women despite demanding roles they often engaged with . We also did not find any statistically significant relationship between quality of sleep and other caregivers and patients characteristics such as caregiver’s age, employment status, educational level, duration of care-giving, onset of stroke illness, and age of the patient. Some previous studies had reported an association between older age and poor quality of sleep [28,29].
Consistent with the existing literature, we found a significant positive correlation between poor quality of sleep and high level of caregivers’ burden among the participants. The association between the quality of sleep and caregivers’ burden remained significant on regression analysis. This findings is in accordance with previous studies that associated poor quality of sleep with high level of caregivers’ burden [24,30]. Stroke is associated with a number of neurobiological changes with concomitant negative impact on the quality of sleep of the patient, and consequently those of their caregivers . The normal sleep wake circadian rhythm is significantly disrupted in patients with stroke, and this has been associated with poor clinical outcomes including post stroke apathy . Furthermore patients may suffer from stroke-induced autonomic dysfunction which has been associated with sleep disordered breathing . Poor quality of sleep in the patients impacts negatively on the caregiver’s quality of sleep. The subsequent adjustment of the caregivers’ sleep-wake systems to the demands of care-giving may explain the poor quality of sleep experienced by caregivers of patients with chronic disorders . The physical and emotional demands of caring for a patient with chronic disorders such as stroke are huge and caregivers often need to make adjustments in their personal lives to keep up with these tasks. Caregivers of patients with stroke may be awakened during the night to render some assistance to the patients. Depending on the severity of stroke, caregivers may also be saddled with the responsibilities of helping with activities of daily living, movements and supervisory roles such as ensuring clinic appointments .
The significant positive correlation between caregiver’s poor quality of sleep and psychological distress among caregivers of patients with stroke in the current study are compatible with previous studies on the subject [22,35]. Bhattacharjee et al. in a prospective study among 111 caregivers of patients with stroke reported an association between poor quality of sleep and significant psychological distress in the caregivers . Negative affect such as excessive rumination and worry had been linked to the development of poor quality of sleep in caregivers . Having to deal with the patient’s demanding behaviours in addition to the enormous roles of care-giving were significant sources of psychological distress in the caregivers of patients with stroke . Out of pocket financing of health care in sub-Saharan Africa may be a source of the heightened psychological distress exhibited by these caregivers, as caregivers had to think of how to raise money to care for their care recipients, in addition to the caregiver’s financial obligations. The financial burden of care-giving may ultimately cause disruptions in the pattern of sleep of the caregivers.
To some extent, bilateral relationship exists between poor quality of sleep and psychological distress. Elevated levels of psychological distress can lead to alterations in the functioning of the hypothalamicpituitary- adrenal axis eventually contributing to poor sleep quality . Psychological distress experienced by caregivers of patients with chronic disorders such as stroke is a major detrimental health consequence that has been linked with long term care-giving . In the current study, a strong association was found between poor quality of sleep and psychological distress in the caregivers of patients with stroke, and the association remained significant on regression analysis.
We found no significant statistical relationship between quality of sleep and use of alcohol or coffee by the caregivers. This is somewhat surprising as one might have inferred that the use of psycho-stimulant such as coffee could have worsened the quality of sleep. Previous studies have attributed poor quality of sleep to excessive intake of coffee .
This study need to be interpreted within the context of the following limitations: The assessment of quality of sleep, caregivers’ burden and psychological distress was based on self report, which may be prone to recall bias. Both polysomnographic and actigraphic objective laboratory measures of sleep were not assessed in this study, objective assessments as these would have added more insight to the study. These measures are however scarce and quite expensive in a low resource setting as ours. Also being a cross-sectional study, we were unable to determine the causal link between quality of sleep, burden and psychological distress respectively. Likewise, the lack of data on the severity of stroke illness which could have contributed to the caregivers’ burden with possible negative effects on their quality of sleep limits the generalisation of the results to all caregivers of stroke patients and to the general population.
The strengths of this study are that we used a standardized instrument (PSQI) which has been widely validated internationally to assess the quality of sleep. Our study has also provided important information on the correlates of poor quality of sleep in caregivers of patients with stroke in a locality that is poorly researched.
This study reported a moderate rate of poor quality of sleep among caregivers of patients with stroke. Our findings also showed that the poor quality of sleep in the caregivers was significantly associated with high level of burden and psychological distress in the caregivers. Our findings underscore the need to screen caregivers of patients with stroke for sleep problems and improve access to timely interventions for management of those with sleep problems. Further multi-centered studies are needed to confirm and extend these findings in a larger sample.
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