Abstract
Background: The theory of heart failure (HF) self-care proposes that confidence mediates relationships between social support and self-care behaviors.
Objective: This study aimed to examine the effects of supportive relationships on self-care behaviors and the mediating effects of self-care confidence in HF outpatients.
Methods: Structural equation modeling (SAS version 9.1, SAS Institute Inc, Cary, North Carolina) was used to examine the influence of supportive relationships and self-care confidence on self-care management and maintenance in a cross-section of patients with HF (n = 97; age = 56 years; 57% men; 45% African American; 55% married). Models included 3 variables characterizing supportive relationships: marital status (1 = currently married, 0 = not currently married), social network size (number of persons available to provide support), and perceived social support (Medical Outcomes Study Social Support Scale). To account for the effects of severity of illness, 2 measures characterizing severity of HF were included: left ventricular ejection fraction and New York Heart Association functional classification of HF. The Self-Care of Heart Failure Index (version 4) was used to measure self-care confidence, management, and maintenance. A consensus of fit indices estimated overall model fit.
Results: Initial models fit the data; however, to improve fit and identify the most parsimonious models, 3 nonsignificant paths were removed, and modified models, including only social support and social network size, were proposed and tested. Modified models fit the data well and accounted for 15% in the variance in self-care maintenance ([chi]2P = .29) and 18% of the variance in self-care management ([chi]2P = .631). The indirect effect of social support ([beta] = 0.37; P = .0004) through self-care confidence ([beta] = 0.35; P = .0002) on self-care management, in the absence of a significant direct effect, supports the hypothesis that self-care confidence mediates the relationship between social support and self-care management. Social network size had a negative effect on self-care confidence ([beta] = -0.22; P = .029), but this effect was mediated by self-care confidence ([beta] = 0.33; P = .0002), which reduced the total negative effects. Self-care confidence was the best predictor of self-care management. In the self-care maintenance model, direct ([beta] = 0.27; P = .003) and indirect effects of social support ([beta] = 0.37; P = .0002) on self-care maintenance through self-care confidence ([beta] = 0.22; P = .001) attenuated negative effects of social network size ([beta] = -0.22; P = .0145). Social support was the best predictor of self-care maintenance.
Conclusions: Findings support the positive influence of social support on self-care behaviors. Self-care confidence mediated the relationship between social support and self-care behaviors and had direct influence on these behaviors as well. This suggests that self-care confidence and self-care behaviors can be enhanced by improving the quality of social support.