Mediators of the Effect of an Educational Intervention on Health-Related Quality of Life in Patients With Heart Failure: A Causal Mediation Analysis.

BACKGROUND

Although nursing interventions improve outcomes in heart failure (HF), the mechanisms underlying their effects on health-related quality of life (HRQOL) remain unclear.

OBJECTIVE

Using a causal mediation framework, we examined whether HF knowledge, self-care behaviors, self-care confidence, or social support mediated the effect of an educational intervention on HRQOL in patients with HF.

METHODS

We analyzed data from a randomized controlled trial of an educational intervention for patients with HF. The intervention group (n = 60; 64.61 ± 13.75 years; 50.0% female) received individual education plus 8 weeks of telephone follow-up, while the control group (n = 62; 67.89 ± 13.31 years; 51.7% female) received usual care. Causal mediation analysis was used to explore the pathway between intervention assignment and HRQOL at 6 months, with HF knowledge, self-care behaviors (ie, overall self-care, self-care management, and self-care maintenance), self-care confidence, and social support measured at 3 months as potential mediators.

RESULTS

Intervention assignment was significantly associated with HF knowledge, overall self-care, self-care maintenance, self-care management, and self-care confidence at 3 months (all P < .05). After adjusting for age, gender, and baseline scores, overall self-care (indirect effect -7.18, 95% CI -13.48 to -2.35) and self-care maintenance (indirect effect -3.02, 95% CI -7.94 to -0.07) demonstrated significant indirect effects. Overall self-care and self-care maintenance also had significant indirect effects between intervention and physical HRQOL, but no mediator was significant for emotional HRQOL.

CONCLUSIONS

Educational interventions can improve HRQOL of patients with HF by enhancing their self-care, particularly treatment adherence and self-monitoring. However, additional strategies are needed for emotional HRQOL.