Socio-demographic and clinical determinants of poor self-care in patients with heart failure and diabetes mellitus

Background: Patients with both Heart Failure (HF) and Diabetes Mellitus (DM) are at risk of severe adverse outcomes. Self-care is vital in both conditions. The effect of DM on HF self-care is unclear and determinants of poor self-care in HF-DM patients are unknown. Objectives: To compare self-care of HF patients with and without DM; to estimate the effect of DM on self-care of HF patients; to identify socio-demographic and clinical determinants of self-care in HF-DM patients. Methods: A multicentre cross-sectional observational study was conducted. 1192 adults with confirmed diagnosis of HF were enrolled. Socio-demographic and clinical data were collected from medical records. Self-care maintenance, management and confidence were measured by the Self-Care of Heart Failure Index (scores range 0-100; higher scores=better self-care). Self-care of HF-DM patients versus HF without DM was compared by linear regression. Multiple linear regressions were performed to estimate the effect of DM on self-care of HF patients and to identify determinants of self-care in HF-DM patients. Results: 379 HF patients (31.8%) were affected by DM. Self-care was sub-optimal in HF patients with and without DM (means range from 53.2 to 55.6). Self-care maintenance (p=0.13), management (p=0.21) and confidence (p=0.51) were not statistically different between HF patients with versus without DM. No statistically significant associations were found between the presence of DM and self-caremaintenance (p=0.12), management (p=0.21) or confidence (p=0.51) of HF patients. Number of medications (p=0.04), cognitive status (p=0,04), New York Heart Association (NYHA) functional class (p=0.01) and self-confidence (p<0.01) were determinants of self-care maintenance in HF-DM patients. Number of medications (p=0.02), cognitive status (p=0.01) and self-care confidence (p<0.01) were determinants of self-care management. Number of medications (p=0.01), cognitive status (p<0.01) and family income (p=0.01) were determinants of self-care confidence. Conclusions: Self-care of HF-DM patients is poor but no worse than the self-care of HF patients without DM. HF-DM patients taking fewer medications, having low income, low self-care confidence, limited cognitive function and worse NYHA class are at higher risk of poor self-care. Future studies are needed to describe DM self-care in HF-DM patients, to develop and test interventions, and to evaluate the effect of DM self-care on HF-DM patients’ outcomes