Depressive Symptoms Moderate the Relationship Among Physical Capacity, Balance Self-Efficacy, and Participation in People After Stroke

Introduction Approximately 795,000 people in the United States experience a stroke each year, making it one of the leading causes of long-term disability in the United States. (1) Community participation [...]
Objective. It was previously found that balance self-efficacy mediated the relationship between physical capacity and participation after stroke. The effect of other factors that influence participation, such as depression, on this relationship has not been explored. This study examined the effect of symptoms of depression on the mediated relationship between physical capacity and participation by balance self-efficacy in individuals after stroke. Methods. In this cross-sectional study, 282 persons with chronic stroke (>6 months) were classified as having either low or high Geriatric Depression Scale scores. This study used a multiple group structural equation model to test moderated mediation by comparing a constrained model (indicating no effect of depression on the mediation) and an unconstrained model (indicating an effect of depression on the mediation). The models were compared using a chi-squared difference test. Results. The chi-squared difference test suggested that the unconstrained model was a better fit, indicating that depressive symptoms moderated the mediated relationship between physical capacity and participation ([chi square][.sub.(3, N =282)] = 9.0). In the Low Depression group, a significant indirect effect indicated that balance self-efficacy did mediate the relationship between physical capacity and participation. There was no significant indirect effect in the High Depression group. Conclusion. The results suggest the relationship between physical capacity and participation appears to be mediated by balance self-efficacy in individuals after stroke with low reports of depressive symptoms, but in those with high reports of depressive symptoms, physical capacity and balance self-efficacy are unrelated to participation. Impact. Targeting balance self-efficacy to improve post-stroke participation may be beneficial only for individuals with low reports of depression. In individuals after stroke with high reports of depression, treatment should include and emphasize the treatment of those depressive symptoms. Additional work further examining these complex relationships is warranted. Keywords: Community Participation, Depression, Mediation, Moderation, Self-Efficacy, Stroke, Structural Equation Model