Restricted Participation in Stroke Caregivers: Who Is at Risk?

Archives of Physical Medicine and Rehabilitation journal homepage: www.archives-pmr.org Archives of Physical Medicine and Rehabilitation 2015;96:1284-90

ORIGINAL RESEARCH

Restricted Participation in Stroke Caregivers: Who Is at Risk? Alisa Grigorovich, PhD,a Samantha Forde, MScOT,a Dahlia Levinson, MScOT,a Marina Bastawrous, MSc,b Angela M. Cheung, MD, PhD, FRCPC,c Jill I. Cameron, PhDa From the aDepartment of Occupational Science and Occupational Therapy, University of Toronto, Toronto, ON; bRehabilitation Science Institute, University of Toronto, Toronto, ON; and cDepartment of Medicine, University Health Network, University of Toronto, Toronto, ON, Canada.

Abstract Objective: To identify caregiver-, stroke survivore, and caregiving situationerelated factors that are associated with caregivers’ restriction from participation in their normative activities (ie, participation restriction) over the first 2 years poststroke. Design: Longitudinal cohort study. Setting: Acute care facilities and community. Participants: A secondary data analysis of caregiver/survivor dyads (NZ399). Interventions: Not applicable. Main Outcome Measures: Data were collected at 1, 3, 6, 12, 18, and 24 months poststroke. The primary outcome was caregivers’ participation restriction and was assessed using the Caregiver Impact Scale. Caregivers also provided demographic information and completed standardized measures to capture assistance provided, mastery, and depression. From stroke survivors we collected demographic characteristics, stroke severity, and cognitive and physical functioning. Data were analyzed using individual growth curve modeling. Results: Participation restriction level improved over time. Caregiver factors associated with restricted participation included younger age, being employed, higher depression, and lower mastery level. Stroke survivor factors associated with caregivers’ restricted participation included hemorrhagic stroke, more severe stroke, more physical and memory impairments, and lower participation. Significant factors related to the caregiving situation included providing high levels of assistance and caring for a spouse. Conclusions: Depressed younger caregivers, with low levels of mastery, who provide high-intensity support to spouses with cognitive difficulties may be at risk. Screening for these factors may help identify stroke families at risk for poor outcomes and may be used to more efficiently allocate health resources. Archives of Physical Medicine and Rehabilitation 2015;96:1284-90 ª 2015 by the American Congress of Rehabilitation Medicine

Stroke is a leading cause of long-term disability in adults.1 Survivors often experience physical and/or cognitive impairments which compromise their independence, performance of basic daily activities, and community reintegration. Informal caregivers (eg, family members) play an important role in supporting survivors as they transition through the health care system and reintegrate into the community.2-5 However, as a result of taking on the demands

Supported by the Canadian Stroke Network, the Social Sciences and Humanities Research Council (grant no. 839-2000-1060), and the Canadian Institutes of Health Research New Investigator Award and Senior Investigator Award. Disclosures: none.

of caregiving, caregivers may neglect their own health and can experience negative health outcomes (eg, depression, anxiety).6-9 Caregivers’ participation in valued activities and life roles (eg, employment, leisure, social relations) has been consistently associated with their well-being.10-12 Among various populations, including acute respiratory distress syndrome,13 cancer,14-16 dementia,12 and mixed illness,17-19 caregivers who were not able to maintain their participation experienced negative outcomes (eg, depression, increased stress, sleep disruption, poor cardiovascular function, poor life satisfaction). Conversely, there is also evidence that those who are able to maintain participation report lower levels of burden and higher levels of well-being, happiness, and life satisfaction.19-21

0003-9993/15/$36 - see front matter ª 2015 by the American Congress of Rehabilitation Medicine http://dx.doi.org/10.1016/j.apmr.2015.03.004

Participation restriction in stroke caregivers Participation restriction can be conceptualized as experiencing a difficulty in engaging, or participating, in valued activities or life roles.22 Previous research suggests that caregivers’ participation restriction is associated with spending more hours a day caregiving, having less social support, and caring for someone who is more functionally impaired.23 Spouses also report lower levels of participation than other informal caregivers (eg, children, siblings, friends),24 and women may be more likely to reduce their participation as a result of caregiving activities than men25; however, evidence of sex- and relation-based differences in participation is inconsistent across the literature.26,27 Research in survivors has also shown that survivors’ participation restriction is associated with older age, being a woman, greater stroke severity, poorer functional and cognitive status, and comorbidities.28-31 Our knowledge about participation restriction in stroke is limited because research to date has primarily focused on examining it as a mediator of caregivers’ level of distress and/or depression, rather than exploring its specific risk factors.12,32 Most studies have also been cross-sectional in design. Consequently, although we know that stroke caregivers experience difficulties in maintaining their participation,33 we do not yet understand how this changes over time or the factors that are associated with restriction. To fill this gap in the literature, we examined participation restriction in the first 2 years poststroke. We had the following 2 aims: (1) to determine whether caregivers’ participation restriction changes over time, and (2) to identify caregiver-, stroke survivore, and caregiving situationerelated factors that are associated with caregivers’ participation restriction.

Methods Research design and procedure This article provides a secondary analysis of data collected in a longitudinal cohort study of individuals who survived their first stroke and their informal caregivers.20,34,35 Members of the acute care clinical team at each study site identified eligible caregiver/ survivor dyads and approached them to participate. Data were collected by phone with trained research assistants during structured, 1-hour long interviews. The full cohort (Y1 sample) completed questionnaires at 1, 3, 6, and 12 months poststroke. A subset of these participants, from one of the sites, also completed the same questionnaires at 18 and 24 months poststroke (Y2 sample).

Participants Dyads were recruited from hospitals in 3 urban cities in Canada while the survivors were still in the acute stages of recovery.20,34 Inclusion criteria were survivors who had their first hospitalization for either hemorrhagic or ischemic stroke and were discharged home. Caregivers were defined as a family member (eg, partner/ spouse, child) or friend who was primarily responsible for providing and/or coordinating the survivors’ care after hospital discharge without financial compensation. All participants had to be able to read and speak English or French to complete the assessments; those who could not do this for reasons of aphasia, cognition, or language were excluded.

List of abbreviations: IGC individual growth curve

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Measures With the exception of the baseline variables, all measures were administered at every interview. Unless otherwise noted, all measures administered are widely used in stroke and caregiving research and have good psychometric properties.36-38 Baseline Participants provided sociodemographic information (eg, age, marital status, relation to survivor, living situation, employment status prestroke). Comorbid conditions in survivors were assessed using the Charlson comorbidity index.39,40 Higher scores indicate more comorbidity (range, 0e6). The Canadian Neurological Scale38,41 was used as an indicator of survivors’ baseline stroke severity. Scores on this scale range from 1.5 to 11.5, with lower scores indicative of poorer neurologic functioning and higher stroke severity. Finally, a review of survivors’ hospital charts provided additional clinical information (eg, stroke type, location of stroke). Main outcome Caregivers’ level of participation restriction at each time point was assessed using the Caregiver Impact Scale. The Caregiver Impact Scale is a 14-item Likert scale that measures the impact providing care has on caregivers’ abilities to maintain participation in 14 lifestyle domains (ie, employment, recreation, social relations, housework).16 Caregivers were asked to rate their restriction in each domain on a scale of 1 (not at all) to 6 (very much). Examples of questions include the following: How much do your caregiving responsibilities interfere with your employment? How much do your caregiving responsibilities interfere with your active recreation? This scale is a modification of the Devin et al Illness Intrusiveness Rating Scale,42 which has demonstrated extensive reliability and validity. Higher scores on the Caregiver Impact Scale indicate more participation restriction (range, 0e84). The Caregiver Impact Scale has been used in stroke and cancer caregiving research and demonstrates good internal consistency (aZ.87e.88).16,20,34,35 Internal consistency in the current study ranged from .84 to .93 across the 6 data collection time points. Other measures Caregivers’ symptoms of depression were assessed using the 20item Center for Epidemiologic Studies - Depression.43 Higher scores denote more depressive symptoms (range, 0e60). The amount of assistance caregivers provided to survivors with daily, instrumental, and medical activities was assessed using the 17item Caregiver Assistance Scale. Scores on this scale range from 0 to 102, with higher scores indicating the provision of more assistance. This scale has been previously used in stroke and cancer caregiving populations and demonstrates good internal consistency (aZ.85e.90).16,35 Caregivers also indicated whether the survivor received any community services in the last month using a checklist of 7 services (eg, physiotherapy, dietician). Caregivers’ physical health was assessed using the physical component summary score from the Medical Outcomes Study 36Item Short-Form Health Survey.38,44 Scores on this scale range from 0 to 100, with higher scores indicative of better physical functioning. Caregivers’ perceived control over life was measured using the Pearlin et al 7-item mastery scale.45,46 Higher scores indicate higher levels of mastery (range, 7e28). Finally, caregivers also rated the presence of behavioral and psychological symptoms in survivors using the 37-item Brain Impairment

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Behavior Scale.47 This scale assesses the presence of apathy, depression, memory/comprehension, and irritability in survivors; higher scores reflect a greater intensity of these symptoms. Survivors also completed measures at each time point. Survivors’ global cognitive status was assessed using the Mini-Mental State Examination.48 Scores on this scale range from 0 to 30, with scores <24 suggesting the presence of cognitive impairment. Memory and communication abilities, physical health, and level of participation in valued activities (eg, work, social, leisure) were measured using the Stroke Impact Scale.49 This is a 64-item questionnaire measuring poststroke outcomes in 8 domains. Because survivors’ cognition was assessed using 2 measures (ie, Mini-Mental State Examination, Stroke Impact Scale subscales), these were grouped together to create a composite cognition score. Each test score was first transformed into a standardized score by centering to its mean value and divided by its SD. This was done for the purpose of creating a more robust measure.50

Statistical analyses SPSS version 22.0a was used to calculate summary statistics, examine the data, and explore differences in the 2 study samples. Receipt of community services was skewed because a large percentage of the sample did not receive any services. As a result, this variable was dichotomized (0Zno services, 1Zat least one service received). Missing data in the sample were <5%. For the purposes of the individual growth curve (IGC), participants are allowed to miss waves of data collection and still be included in the analyses. To facilitate comparison across the models, the same sample must be included in each analysis. As a result, we replaced missing independent variable data using the last observation carried forward.51 IGC modeling was used to identify factors associated with change in caregivers’ participation restriction during the first 2 years poststroke and to identify factors associated with it. This approach had several advantages over traditional methods of

Table 1

longitudinal data analysis52-54 and was performed using Proc Mixed in SAS version 9.2.b All of the assumptions for IGC modeling were examined and met (ie, linearity of change, lack of multicollinearity, residuals normally distributed and homoscedastic). There were no issues of multicollinearity present in the data, as suggested by a correlation >.80.55 In total, 5 models were constructed. The unconditional means model (model 1) provided an estimate of participation restriction across all the participants and across all the waves of data collection in the Y1 sample. The unconditional growth model (model 2) assessed change in participation restriction over time in the Y1 sample. The full model (model 3) tested all the variables of interest in 1 model in the Y1 sample. To test the full model, with 22 independent variables and a minimum of 10 participants per variable, we needed a sample of at least 220 caregiver/survivor dyads.56 To avoid dismissing any potentially important variables, the simplest model (model 4) included only the variables with P
.15. This model was obtained by deleting variables with the highest P value >.15 one at a time and rerunning the model until all the remaining variables had P<.15. The fit statistics (ie, Akaike information criterion) associated with this model were also smaller than with the full model (model 3), indicating more accurate congruence of the variables to the model. Finally, because of the smaller Y2 sample, only the simplest model from Y1 (model 4) was tested with the Y2 sample (model 5) to verify whether the same set of variables remained significant in the second year.

Results The Y1 sample included 399 stroke survivor/caregiver dyads who were followed for 1 year after the stroke; a subset of 80 dyads (Y2 sample) also completed the same measures at 18 and 24 months poststroke (table 1). The 2 samples were similar to each other.

Stroke survivor and caregiver sociodemographic and illness characteristics

Participant Characteristic

Y1 Sample (NZ399)

Y2 Sample (nZ80)

Y1eY2 (nZ319)

P

Survivor age, y (at time of stroke) Survivor sex Male Stroke type Ischemic Hemorrhagic Stroke location Hemispheric Cerebellum Brainstem Survivor CNS (at baseline) Caregiver age, y (at time of stroke) Caregiver sex Male Caregiver relationship to survivor Spousal Caregiver employment status prestroke Employed

66.440.73

61.9616.15

67.5514.00

.01 .25

235 (59)

42 (53)

193 (61)

354 (89) 43 (11)

73 (92) 6 (8)

281 (88) 37 (12)

329 (83) 44 (11) 24 (6) 8.300.13 58.440.77

67 (84) 9 (11) 3 (4) 8.622.57 57.0614.51

262 (82) 35 (11) 21 (7) 8.222.70 58.8015.01

.42

.65

.22 .37

23 (31)

28 (37)

87 (29)

.16

278 (70)

60 (78)

214 (68)

.10

136 (34)

33 (51)

106 (38)

.07

NOTE. Values are mean  SD, n (%), or as otherwise indicated. Abbreviation: CNS, Canadian Neurological Scale.

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Main analysis The models are presented in table 2. Caregivers’ mean level of participation restriction across the 4 waves of data collection was provided by the intercept of model 1 (16.06). Model 2 showed that caregivers’ level of participation restriction significantly decreased over the first year (P<.0001), suggesting that caregiving responsibilities had less of a negative impact on their ability to participate in valued activities. The full model (model 3) indicated that participation restriction was significantly associated (P<.05) with caregivers’ younger age, being employed, more depression symptoms, and lower mastery. Stroke survivor factors that influenced caregivers’ participation restriction included more severe stroke, poorer physical functioning, more memory/comprehension impairment, and lower community participation. Significant factors related to the caregiving situation included providing higher levels of assistance and caring for a spouse. The simplest model (model 4) identified the same set of factors as significant using P<.05. Participation restriction in the Y2 sample (model 5) was no longer significantly associated with caregivers’ level of mastery, employment, spousal relation, or survivors’ memory impairment or physical functioning. It was, however, still significantly

Table 2

associated with caregivers’ younger age, higher levels of caregiver depression, providing higher levels of assistance to survivors, and lower survivors’ community participation. Additionally, having a hemorrhagic stroke provided an increase to statistically significant levels.

Discussion This study aimed to determine whether stroke caregivers’ participation restriction changed over the first 2 years of providing care and to identify significant factors associated with restriction. To our knowledge, this is the first study that addressed this aim and simultaneously examined caregiver-, survivor-, and caregiving situationerelated factors in a longitudinal sample. In our study, caregivers’ participation restriction decreased over time and was not related to survivors’ sex, age, depression, or comorbidities, but it was related to survivors’ memory impairment, lower participation, poorer physical functioning, hemorrhagic stroke, and greater stroke severity. In terms of caregiver-related factors, participation restriction was related to caregivers’ younger age, being employed, higher symptoms of depression, and lower mastery, but it was not related to their sex or physical health. Significant

Caregivers’ participation restriction (Caregiver Impact Scale as outcome): results of the IGC analyses

Fixed Effects Initial Status, p0i

Model 1

Model 2

Model 3

Model 4

Model 5

Intercept Time Caregiver is a woman Caregiver is spousez Caregiver is employedk Caregiver physical health Caregiver age Caregiver depression Caregiver mastery Caregiver assistance Survivor receiving community services Survivor is a woman Survivor age Survivor baseline stroke severity Survivor had hemorrhagic stroke{ Stroke location Survivor baseline comorbidities Survivor overall cognition Survivor depression Survivor irritability Survivor apathy Survivor memory/comprehension difficulties Survivor physical functioning Survivor participation Model fit (Akaike information criterion)

16.1 (0.9)*

18.0 (0.9)* 0.5 (0.1)*

27.4 (7.2)* 0.1 (0.1) 0.4 (1.7) 4.8 (1.7)x 3.3 (1.1)x 0.0 (0.1) 0.2 (0.1)* 0.5 (0.1)* 0.4 (0.1)y 0.2 (0.0)* 0.2 (0.7) 0.5 (1.7) 0.0 (0.1) 0.5 (0.2)* 3.0 (1.8) 0.8 (1.0) 0.1 (0.4) 0.4 (0.2) 0.4 (0.6) 0.2 (0.5) 0.6 (0.6) 2.5 (0.7)y 0.1 (0.0)y 0.1 (0.0)y 8534.0

24.8 (5.6)* 0.1 (0.1)

21.9 (11.8)y 0.3 (0.2)

3165.0

3041.4

5.1 (1.4)* 3.3 (1.0)x 0.2 0.5 0.4 0.2

(0.1)* (0.1)* (0.1)x (0.0)*

3.2 (3.1) 0.8 (19) 0.3 0.7 0.1 0.3

(0.1)x (0.1)* (0.2) (0.1)*

0.6 (0.2)y 2.9 (1.8)

1.0 (0.5)y 8.6 (4.1)y

0.4 (0.2)

0.2 (0.5)

3.1 (0.7)* 0.1 (0.0)x 0.1 (0.0)x 8517.8

2.69 (1.4) 0.1 (0.1) 0.1 (0.0)y 1763.6

NOTE. Values are estimates (SEs). Not all variables were tested in all models. Blank cells indicate the variable was not tested in the model. Model 1, unconditional means model; Model 2, unconditional growth model; Model 3, Y1 sample full model; Model 4, Y1 sample simplest model; Model 5, repeat of model 4 with Y2 sample. * P<.001. y P<.05. z Coded as 0 (nonspouse) or 1 (spouse). x P<.01. k Coded as 0 (not employed) or 1 (employed). { Coded as 0 (ischemic) or 1 (hemorrhagic).

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1288 caregiving situationerelated factors associated with participation restriction included a spousal relation to the survivor and caregivers providing higher levels of assistance. Overall, caregivers’ level of participation restriction decreased over time, suggesting that most caregivers were able to re-engage in valued activities. This is consistent with other research that has shown that although many stroke caregivers report being overwhelmed by caregiving in the beginning, they experience decreasing levels of stress and depression over time.34,57 Caring for a stroke survivor during the first year poststroke may be more challenging as caregivers learn to balance caregiving with other life roles and as survivors continue to recover and begin to reintegrate into the community. Providing respite care services in the community during the first year may assist caregivers with maintaining their participation and enhance their long-term health and well-being.58,59 Caregivers who were younger, employed, and caring for a spouse were more likely to experience participation restriction. These findings are in line with previous research in stroke and mixed-illness populations, that spousal caregivers report lower participation rates24,33 and that younger stroke caregivers may experience more strain and lifestyle changes than older caregivers.60 There is also evidence that younger survivors experience difficulties with social integration and resuming occupational roles, despite having better functional outcomes than older survivors.61 Taken together, this suggests that although most caregivers were able to adapt over time, younger spousal caregivers may need access to age-appropriate psychoeducational interventions and employment supports for further assistance. Survivor-related factors and level of caregiver assistance were also found to be associated with caregivers’ participation and suggest a reciprocal relation between caregivers’ and survivors’ health outcomes. Previous research in stroke and mixed-illness populations has similarly shown that survivors’ participation is related to their illness severity.23,31,62 Survivors’ cognitive functioning has also been shown to be a predictor of survivors’ participation,29,30,63,64 and memory difficulties in particular have been identified as predictive of restriction, independent of mood.65 Although evidence that stroke type is related to functional outcomes is mixed, some studies suggest that survivors with hemorrhagic strokes may have greater disability.66,67 Our findings that caregivers’ participation restriction was associated with providing higher levels of assistance to survivors and with more severe stroke, poorer memory, and hemorrhagic stroke is therefore consistent with the literature. However, our finding with respect to stroke type should be interpreted with caution because of the small number of individuals with hemorrhagic stroke (nZ6). Cognitive difficulties pose a barrier for survivors’ reintegration and social participation and may also increase the demands and complexity of assistance that caregivers provide. Increasing survivors’ access to cognitive rehabilitation and supportive interventions in the community may therefore help support both caregivers’ and survivors’ participation. Finally, caregivers’ participation restriction was significantly associated with higher symptoms of caregiver depression in both the Y1 and Y2 samples and with lower caregiver mastery in the Y1 sample. Although depression has consistently been linked with participation restriction in both caregiver and patient populations, the relation between these outcomes is unclear and may be bidirectional.17,30,31 Therefore, participation restriction may bring on depression, and depression may exacerbate or maintain participation restriction. Having a greater sense of mastery is thought to be one mediator of this relation and has also been

A. Grigorovich et al associated with better psychological well-being for stroke caregivers.20 A possible explanation for our results is that caregivers who have a greater sense of mastery and control over their life may be better able to balance the demands of caregiving with other life roles and therefore maintain their participation. These findings suggest that caregivers’ mastery may be an important protective factor.

Study limitations Although this study has a number of strengths, some limitations are worth noting. Only patients who were able to communicate and cognitively able to provide informed consent participated, the average stroke severity level was relatively low, and the number of survivors with hemorrhagic strokes was small. Given that the latter 2 factors were also found to be associated with restriction, future studies will need to further investigate these relations. The Y2 sample was also smaller and included participants from 1 geographic area. As a result, differences observed between the Y1 and Y2 models must be interpreted with caution.

Conclusions Supporting stroke caregivers’ participation in life roles and valued activities has important implications for caregiver long-term wellbeing and capacity to continue to provide care to survivors. Despite this, limited research to date has focused on stroke caregivers’ participation or on exploring factors that may be used to identify caregivers at risk for participation restriction. This study contributed to this gap in the literature and showed that participation restriction improved over the first 2 years poststroke. Furthermore, participation restriction was significantly associated with caregivers’ younger age, being employed, lower mastery level, and higher depression symptoms. Significant survivorrelated factors included their physical and cognitive functioning, hemorrhagic stroke, and level of participation. Providing high levels of assistance and being the spouse of the survivor were significant situational factors. Screening for these factors may help identify stroke families at risk for poor outcomes and may be used to more efficiently allocate health resources. Future research directions could include further exploring of the relations between mastery and caregivers’ participation and investigating the experiences of caregivers caring for survivors with hemorrhagic strokes.

Suppliers a. SPSS version 22.0; SPSS. b. SAS version 9.2; SAS Institute.

Keywords Caregivers; Longitudinal studies; Rehabilitation; Stroke

Corresponding author Jill I. Cameron, PhD, Department of Occupational Sciences and Occupational Therapy, University of Toronto, 160-500 University Ave, Toronto, ON M5G 1V7, Canada. E-mail address: jill. [email protected]. www.archives-pmr.org

Participation restriction in stroke caregivers

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