Does cognitive impairment predict poor self-care in patients with heart failure?

Cognitive impairment occurs often in patients with chronic heart failure (CHF) and may contribute to sub-optimal self-care. This study aimed to test the impact of cognitive impairment on self-care. In 93 consecutive patients hospitalized with CHF, self-care (Self-Care of Heart Failure Index) was assessed. Multiple regression analysis was used to test a model of variables hypothesized to predict self-care maintenance, management, and confidence. Variables in the model were mild cognitive impairment (MCI; Mini-Mental State Exam and Montreal Cognitive Assessment), depressive symptoms (Cardiac Depression Scale), age, gender, social isolation, education level, new diagnosis, and co-morbid illnesses. Sixty-eight patients (75%) were coded as having MCI and had significantly lower self-care management (eta(2)= 0.07, P < 0.01) and self-confidence scores (eta(2)= 0.05, P < 0.05). In multivariate analysis, MCI, co-morbidity index, and NYHA class III or IV explained 20% of the variance in self-care management (P < 0.01); MCI made the largest contribution explaining 9% of the variance. Increasing age and symptoms of depression explained 13% of the variance in self-care confidence scores (P < 0.01). Cognitive impairment, a hidden co-morbidity, may impede patients' ability to make appropriate self-care decisions. Screening for MCI may alert health professionals to those at greater risk of failed self-care.