In order to ascertain more knowledge regarding the complex situation in everyday life of the person with stroke together with their caregiver, this study considered the two individuals as a dyad and combined their life satisfaction. By examining the association between the dyads' combined life satisfaction with the perceived impact of stroke on the one hand and the combined life satisfaction with caregiver burden on the other hand, this study attempted to achieve a dyadic perspective. The findings regarding the dyads combined life satisfaction, met our expectations as approximately 66% of the dyads had a congruent life satisfaction. Furthermore, the dyads combined life satisfaction was significantly associated with the perceived impact of stroke in everyday life and caregiver burden. In the dyads that were dissatisfied the impact of stroke and caregiver burden were significantly higher compared with those dyads that were satisfied with life as a whole.
The greater number of dissatisfied caregivers in the discordant group (19 of 28) was an unexpected result. The dissatisfied caregivers in the discordant group reported a significantly greater caregiver burden compared with caregivers in the satisfied dyads, indicating a potential vulnerability within the dyad and with the possibility of affecting the care recipient [1
]. Even the caregivers who were satisfied with life but whose care recipients were not satisfied, expressed caregiver burden, suggesting other potentially vulnerable dyads. A possible interpretation of these results is that mutuality and reciprocal influences within the dyad, supported in previous studies [9
], impacts everyday life after stroke and has clinical implications for identifying potentially vulnerable dyads.
The discordant dyads were divided in a study by Carlsson and colleagues [19
] in the same way as in the present study but the opposite relation was found; only 9 percent of the spouses in the group of discordant dyads were dissatisfied. One can only speculate regarding the reasons for the differences in the studies. For example, hemisphere location of the insult may have had an impact on life satisfaction for the person with stroke and their caregiver [36
]. Also, spousal stress has been associated with strokes in the left hemisphere, suggesting the effects of impairments in communicative competence [37
]. A closer analysis of discordant dyads would be warranted in future qualitative and quantitative studies in order to broaden the knowledge regarding vulnerable dyads and their needs.
The results of the present study showed that 40% of the dyads were satisfied with life as a whole, representing a greater percentage of satisfied dyads compared with the two previous studies pertaining to combined life satisfaction who found 29% [20
] and 30% satisfied couples [19
]. One reason for this difference might be that the two previous studies had younger participants (median age 53 and 60 years) compared with the median age of 71 for the persons with stroke in the present study. Everyday life may be more demanding in working ages with other responsibilities compared with everyday life for a person that is retired [38
]. Another reason for this difference might be that the previous studies investigated couples, where one of the persons has had a stroke. The group of caregivers that were not spouses or partners was relatively small in the present study, and may or may not have influenced the dyads combined life satisfaction. It is interesting to note however, that the dyads with combined low life satisfaction were partners indicating that being a partner might influence global life satisfaction to a greater extent than being a child or friend to the person with stroke.
The combination of two persons' life satisfaction into one unit establishes a certain relationship between the two individuals in the dyad, and this has been discussed in the literature. Bookwala and Schulz (1996) found that the well-being of one spouse was significantly associated with the well-being of the other in older adults living in the community [39
]. Moreover, perceived needs of the caregivers may be inseparable from the needs of the care recipients [40
]. Despite this, caution is advised in combining two individuals life satisfaction as was done in the present study. Studies show that caregivers and their recipients do not always agree upon the problems [23
]. Despite the measuring of combined life satisfaction, it is also important to capture the perceptions of each person in the dyad and not risk losing the individuals' perspective. Qualitative longitudinal studies of dyads where one of the persons has had a stroke may help compare and contrast issues of individuality as well as mutuality in everyday life.
There were significant differences between the satisfied and the dissatisfied dyads in all SIS domains. A previous study on dyads with combined life satisfaction has shown that the satisfied groups perceived their participation in leisure activities and social life significantly greater than the dissatisfied group [20
]. The present study supports this and provides more comprehensive information on the impact of stroke including all domains of the SIS, even physical and cognitive functioning as well as participation, in relation to combined life satisfaction. It is also interesting to note the differences in the SIS scores of the persons with stroke in the discordant dyads compared with either the satisfied or the dissatisfied dyads (see Table ). The persons with stroke in the one group of discordant dyads experienced greater impacts in cognitive functions (i.e. memory and communication) while the other group had a tendency to experience predominantly physical impacts of their stroke. This is in line with other studies reported in a review article, showing that partners experience greater impact in quality of life when there are cognitive impairments involved compared to physical impairments [42
The greatest impact of stroke was found in the domain participation regarding the persons with stroke in the dissatisfied dyads (see Table ). A dyadic perspective regarding participation is thus warranted in future studies to determine if and how caregivers' participation is also affected.
Limitations of the study
The caregivers' social relation to the individuals with stroke was not homogeneous in the present study, which might have affected the perceived life satisfaction [18
]. Due to the relatively small sample size of those who were not partners, we chose not to further analyze dyads' life satisfaction with regards to social relations. There is a need for future studies with larger populations in order to identify if there are differences between caregivers who are partners or have other social relations to the person with stroke. However, in order to reflect reality as much as possible, all persons identified as a caregiver by the person with stroke were included in this study.
One strength of the present study was that it was hospital based and included even persons with aphasia. Persons with aphasia have been frequently excluded from stroke research according to a systematic review [43
The usage of the division of LiSat-11 into satisfied and not satisfied can be questioned. However, this dichotomization has been found to be valid by the developers of the scale [18
] and has been used in several other studies [20
The small sample size limits the generalizability of the results. However, the study sample was extracted from a cohort who represented a population of all persons admitted to the stroke units during the period of one year. There were differences in the participants in the present study regarding age, gender and stroke severity compared with the persons making up the larger study, which could also limit the generalizability of the results. The larger study group was followed from stroke onset which is considered an advantage in comparison to a number of studies reported in a review article by White [42
] showing that persons recruited to studies regarding caregivers were included when the patient was already receiving services and community support with the risk of misrepresenting the target population. Another limitation is that persons with mild stroke symptoms that may not have been admitted to the hospital or stroke unit or conversely, persons with such a massive stroke admitted to intensive care are underrepresented. The attrition rate was high for both persons with stroke and their caregivers which further calls for caution when extrapolating the results to other populations. There was missing data regarding the caregivers due to incomplete questionnaires returned by mail and possibly restricting the interpretation of the results.
Clinical implications regarding the dyad viewed as a single client could be incorporated in supportive interventions. The fact that the efficacy of interventions for caregivers of persons with stroke has not been confirmed [44
] together with the predominant focus on the person with stroke in clinical guidelines within rehabilitation [41
] motivates the need for a new perspective. A dyadic approach in supportive interventions and rehabilitation programs could be developed and evaluated.
Another clinical implication might be the implementation of client-centred rehabilitation interventions in the home setting. Home rehabilitation provides valuable contextual information [45
] and fosters client and therapist partnerships [46
] and may be especially conducive to individualized interventions based on the dyads' unique needs.
Knowledge regarding combined life satisfaction and the relationship to the perceived problems in everyday life could help expand our understanding of the dyads complex situation after stroke and facilitate identifying those persons in need of support. A greater understanding may than lead to effective rehabilitation interventions which would enable meaningful activities in everyday life and thereby affect life satisfaction for both individuals in the dyad.