Sleep quality and daytime sleepiness are not associated with cognition in heart failure

Background: Individuals with heart failure (HF) exhibit comorbid impairments in both sleep and cognitive performance. Sleep quality has been associated with impaired cognitive performance in HF patients, but reports are inconsistent. In this study, we examined associations between sleep quality, daytime sleepiness, and cognitive function in HF. Methods and results: Participants were 267 (age = 69.1 ± 9.3) mostly Caucasian (74.9%), male (59.6%) stable HF patients recruited from outpatient settings. This cross-sectional study was a secondary analysis of a prospective observational study. Cognitive function domains assessed included: global cognitive function, attention, memory, and executive function. Sleep quality and daytime sleepiness were assessed using the Pittsburgh Sleep Quality Index (PSQI) and the Epworth Sleepiness Scale (ESS), respectively. Separate multiple hierarchical linear regressions were conducted to determine associations between cognitive function and sleep quality and daytime sleepiness, after controlling for sex, New York Heart Association (NYHA) class, education, depressive symptoms, and medical comorbidities. Cognitive function was not associated with sleep quality or daytime sleepiness after alpha inflation corrections were applied. Conclusions: Cognitive function in HF is not associated with sleep quality or daytime sleepiness; other factors may exert greater influence on cognitive performance.