This study supports the efficacy of tailored PST in enhancing the quality of life of community-residing family caregivers of persons with severe disabilities. Caregivers receiving PST showed significant enhancement of problem-solving abilities and a reduction in depressive symptoms over time relative to education-only controls. These findings are consistent with previous studies demonstrating the benefits of PST for caregivers of persons with specific disorders such as stroke (Grant et al., 2002
), spinal cord injuries (Elliott et al., 2008
; Elliott & Berry, 2009
), TBI (Rivera et al., 2008
; Wade et al., 2006a
), and cancer (Nezu et al., 2003
). This study thus provides a step toward validating the benefits of PST for caregivers across diverse medical conditions.
The changes in problem-solving skills in the PST group are consistent with the theoretical model of social problem-solving. The model emphasizes the importance of training in both constructive and dysfunctional problem-solving styles. Previous research on PST with caregivers has documented adaptive change in general problem-solving abilities (Grant et al., 2002
) or in either dysfunctional problem-solving only (Rivera et al., 2008
) or constructive problem-solving only (Elliott et al., 2009
). In contrast, we found significant effects of PST on both problem-solving dimensions. The larger sample size (and thus greater statistical power) of the present study compared with previous work might account in part for this difference.
We also found that PST delivered to caregivers had beneficial effects for care recipients. Even though care recipients did not directly participate in PST, their levels of depressive symptoms declined over time, whereas care recipients whose caregivers were in the control condition showed a stable trajectory of depressive symptoms. This finding adds to the few clinical trials that have examined such indirect effects of caregiver interventions on the well-being of care recipients (e.g., Elliott et al., 2008
; Wade et al., 2006b
Although demonstrating beneficial effects of family interventions on care recipients is important, it is essential that interventions “… be based on theories that delineate mechanisms of change in family processes and skills … necessary to maintain patients’ and family members’ health” (Shields, Chawla, Finley, & Meadors, 2012
, p. 265). Several mechanisms might account for the indirect benefits of caregiver PST for care recipients in our study. One possibility is that caregiver mood (which was improving because of treatment) was directly affecting care recipient mood. This phenomenon commonly goes by the name “emotional contagion” (Hatfield, Cacioppo, & Rapson, 1994
). Emotional contagion refers to the convergence of somatic, behavioral, and emotional states between two or more people. Closely related terms include “affective mirroring,” “emotional convergence,” “emotional transmission,” and “coregulation.” The ubiquity of emotional contagion underlies the growing research and theorizing on the social functions of emotions (Keltner & Haidt, 1999
) and the neurological and physiological basis of empathy, imitation, and affective coregulation (Decety & Meyer, 2008
; Sbarra & Hazan, 2008
There is much evidence for concordance of depressive symptoms and moods in couples and families using both cross-sectional (Joiner & Katz, 1999
; Kiecolt-Glaser & Newton, 2001
) and longitudinal methods (Anderson, Keltner, & John, 2003
; Kouros & Cummings, 2010
; Larson & Almeida, 1999
; Saxbe & Repetti, 2010
). In a longitudinal study of 12,067 participants in the Framingham Heart Study from 1983 to 2001, Rosenquist, Fowler, and Christakis (2010)
found that levels of depression were transmitted in social networks up to three degrees of separation.
Some studies have examined emotional transmission in couples coping with health crises. Segrin, Badger, Dorros, Meek, and Lopez (2007)
found that anxiety in women undergoing breast cancer treatment was consistently associated with that of their partners; the influence ran mostly from partners’ anxiety to that of women with cancer. Similar findings were reported in a study of couples engaged in assisted-reproduction treatment (Knoll, Schwarzer, Pfüller, & Kienle, 2009
In the present study, two models were consistent with a “contagion” effect of caregiver depression on care recipient depression. In the parallel growth curve model, PST directly affected the slope of caregiver depression, which influenced the slope of care recipient depression in the same direction. Thus, PST had an indirect effect on change in care recipient depression via its direct effect on change in caregiver depression. In the alternative direct effects model, caregiver depression was influencing care recipient depression at each assessment.
There are other mechanisms that might explain the benefits of caregiver PST for care recipient well-being. Perhaps caregivers who received training in problem-solving were better able to provide effective care for their loved ones by improving their material conditions or providing better access to treatment resources. These improved conditions could have affected care recipient levels of depression. Our data did not provide evidence that change in caregiver problem-solving was related to care recipient improvements in depression, nor were there treatment group differences in care recipient functional independence. It is possible, however, that self-reported change in problem-solving abilities are an inadequate proxy for objectively measured (or care recipient-reported) positive changes in care recipient circumstances.
Another possible mechanism for the impact of PST on care recipient well-being is suggested by the concept of dyadic coping (Revenson, Kayser, & Bodenmann, 2005
). Most research on caregivers has focused on individual styles of appraising and coping with stressors (Berg & Upchurch, 2007
). In contrast, a dyadic coping perspective emphasizes that close dyads often perceive stressors as “ours” and engage in joint coping efforts, pooling of resources, and sharing information to bring about desired goals. In the present study, it is possible that some caregivers shared their new knowledge with their care recipients, who then applied more constructive habits to their own lives. Unfortunately, we have no means to assess this possibility. Based on the data at hand, the present study most strongly supports a model in which improvements in care recipient depression is a direct effect of improvements in caregiver depression brought about by participation in PST.
Several limitations of this study must be acknowledged. All outcome measures were based on self-reports, and the drawbacks of self-reports and the reliance on a single mode of assessment are well-known. This might be especially true for the social problem-solving scales, for which more research is needed on the relationship between verbal learning of problem-solving protocols and objectively measured problem-solving behavior (Fox & Faw, 2000
). Another limitation is that participants were volunteers who had both the interest and capacity to participate in a home-based educational program. Although randomization ideally provides some control over the effects of biases in response to treatment, our sampling procedure and inclusion criteria could limit our ability to generalize results to a broader population of community-residing caregivers and care recipients. A possible limitation of the study is a lack of a generally applicable “treatment-as-usual” for community-residing family caregivers of people with diverse disabilities. It is possible that the education-only intervention did not provide a realistic control condition, a problem that perhaps extends to most clinical trials of community-based interventions for chronic health conditions. Furthermore, participants were not “masked” to their experimental condition, which could have biased some participant’s responses. It is noteworthy that although caregivers in the control group did not reap the benefits of PST for problem-solving and depression, they reported almost the same levels of satisfaction with their experience in the study. This suggests that control caregivers were provided with an engaging, bona fide alternative intervention. Finally, potential moderators of PST effectiveness, such as gender and ethnicity, were not examined in the present study because of inadequate sample sizes.
We have a final caution about the results of this study. Although the effect of PST on care recipient depression was statistically significant, the clinical significance of the change can be questioned. A few care recipients had substantial decreases in depression scores, but the average decline on the HAMD among care recipients in the PST group was 1 scale point. This is perhaps due in part to low initial levels of depression among care recipients. Our inclusion criteria did not take into consideration caregiver or care recipient depression. Consequently, many nondepressed caregivers and care recipients participated in the study. Despite the restricted ranges on depression scales, significant treatment effects were detected. Future work may find stronger effects if the study is restricted to persons who report higher levels of distress.
Further study of dyadic adjustment following disability is necessary to understand the mechanisms of change on family processes and skills that affect care recipient health and well-being (Shields et al., 2012
). If psychological well-being is indeed contagious throughout social networks, then discovering convenient and effective targeted interventions for even one family member “… might be particularly cost-effective from a societal standpoint, benefitting both them and others” (Rosenquist et al., 2010
, p. 8).