Lower heart rate variability is associated with worse memory function: The Maastricht Study

Background With increasing life expectancy, more individuals will face age-related cognitive difficulties, including Alzheimer's disease. It is, therefore, important to identify early, potentially modifiable risk factors for cognitive impairment. Lower heart rate variability (HRV), reflecting worse cardiac autonomic function, may be one such factor, though its link to cognition remains unclear. Objective This study investigates whether lower HRV is associated with worse cognitive performance. Methods We used population-based cross-sectional data from The Maastricht Study (N = 9187 participants, mean age 59.5 years, 50.2% women, 21% with type 2 diabetes) to investigate the associations of 24-h HRV with memory function, executive function, and information processing speed. Linear regression analyses adjusted for potential cardiovascular confounders were conducted, and we tested for interactions by sex, age, and glucose metabolism status (prediabetes and type 2 diabetes versus normal glucose metabolism). Results After adjusting for covariates, both lower time and frequency domain HRV (per 1 standard deviation [SD]) were associated with worse memory function (-0.04 SD [95%CI -0.06; -0.02] and -0.02 SD [95%CI -0.04; -0.00], respectively), equivalent to aging by 1-1.5 years. HRV was not significantly associated with executive function (-0.00 SD [95%CI -0.02; 0.02] and -0.02 SD [95%CI -0.04; 0.00]) or information processing speed (0.01 SD [95%CI -0.01; 0.03] and -0.00 SD [95%CI -0.02; 0.02]). No interactions with sex, age, or glucose metabolism status were found. Conclusions Lower HRV was associated with worse memory function in mid- to late-life individuals, independent of cardiovascular risk factors.