How comorbidity, self-care confidence and self-care behaviors interact to predict hospitalization in heart failure patients

Purpose: As many as 70% of heart failure (HF) patients suffer from at least one other chronic condition. Comorbidity in HF is associated with frequent hospitalizations. Self-care can mitigate poor outcomes. Yet, lack of confidence is known to interfere with self-care when more than one chronic condition exists. The mechanism by which comorbidity, self-care confidence and self-care behaviors interact to predict hospitalization in HF patients is unclear. The aim of this study was test an explanatory model of predictors of hospitalization by: 1) identifying the contribution of comorbidity to HF self-care behaviors and hospitalization, and 2) testing comorbidity as a moderator of the relationship between self-care confidence and HF self-care behaviors. Methods: We conducted a secondary analysis of data from a cross sectional study of 628 HF patients enrolled across Italy. All participants: 1) had a confirmed diagnosis of HF; 2) were stable in the preceding month; 3) were age > 18 years; and 4) had symptoms in the last month so that we could analyze their symptom management behaviors. Both comorbidity, as measured by the 12 item Charlson Comorbidity Index total score, and hospitalization were evaluated from medical record review. Self-care was measured with the Self-Care of HF Index v.6.2. All three scales (maintenance, management, confidence) yield standardized scores ranging 0-100 with higher scores indicating higher HF self-care. Structural equation modeling and post-hoc simple slope analysis were used to analyze the data.Results: Participants were primarily male (58%), older (73 years old, SD=11) and NYHA class II or III (75%). In model testing, higher numbers of hospitalization were associated with lower self-caremaintenance (i.e. treatment adherence and symptom monitoring) and higher comorbidity. Higher self-care maintenance was associated with higher self-care confidence. Higher self-care management (i.e. symptom management behaviors) was associated with lower comorbidity and higher self-care confidence. Slope analysis showed that comorbidity moderated the relationship between self-care confidence and self-caremaintenance. As the level of comorbidity increased, the effect of self-care confidence on self-care maintenance decreased. The final model fit the data well (fit indices: CFI=0.99, RMSEA=0.03). Conclusion: Self-care confidence plays a key role in the relationship between comorbidity and self-care in influencing hospitalization. When patients have comorbid conditions, interventions designed to improve self-care confidence may help to decrease hospitalizations.