Correlates of cognition among people with chronic heart failure and insomnia

Purpose: This study aimed to describe cognitive characteristics and their associations with demographic and clinical factors among adults with chronic heart failure (HF) and insomnia. Methods: We performed a cross-sectional analysis of baseline data from the HeartSleep Study (NCT#02,660,385), a randomized controlled trial designed to evaluate the effects of cognitive-behavioral therapy for insomnia. Demographic characteristics and health history were obtained. We measured sleep characteristics with the Insomnia Severity Index, the PROMIS Sleep Disturbance Questionnaire, and wrist actigraphy. Sleepiness, stress, and quality of life were measured with validated questionnaires. Measures of cognition included frequency of lapses on the psychomotor vigilance test and the PROMIS cognitive abilities scale where ≥ 3 lapses and a score of ≤ 50, respectively, suggested impairment. These variables were combined into a composite score for multivariable analyses. Results: Of a sample that included 187 participants (58% male; mean age 63.1 [SD = 12.7]), 77% had New York Heart Association class I or II HF and 66% had HF with preserved ejection fraction. Common comorbidities were diabetes (35%), hypertension (64%), and sleep apnea (54%). Impaired vigilant attention was associated with non-White race, higher body mass index, less education, and more medical comorbidities. Self-reported cognitive impairment was associated with younger age, higher body mass index, and pulmonary disease. On adjusted analysis, significant risk factors for cognitive impairment included hypertension (OR 1.94), daytime sleepiness (OR 1.09), stress (OR 1.08), and quality of life (OR 0.12). Conclusions: Impaired cognition is common among people with chronic HF and insomnia and associated with hypertension, daytime sleepiness, stress, and poor quality of life. Trial registration: ClinicalTrials.gov Identifier: Insomnia Self-management in Heart Failure; NCT#02,660,385.