Sex‐specific biomarkers in Alzheimer's disease progression: Framingham Heart Study
Chunyu Liu, Yi Li, Adaora Nwosu, Ting Fang Alvin Ang, Yulin Liu, Sherral Devine, Rhoda Au, P. Murali Doraiswamy
Abstract
Abstract Background Sex differences in Alzheimer's disease (AD) are not well understood. Methods We performed sex‐specific analyses of AD and annualized cognitive decline with clinical and blood biomarker data in participants 60+ years old in the community‐based longitudinal Framingham Heart Study Offspring Cohort ( n = 1398, mean age 68 years, 55% women). Results During 11 years of follow‐up, women were 96% more likely than men to be diagnosed with clinical AD dementia after adjusting for age and education in the younger age group 60 to 70 years ( n = 946; 95% confidence interval [CI], 1.08 to 3.56) although not in the older age group (70+) ( n = 452; hazard ratio = 0.98; 95% CI, 0.68 to 1.53). Sex‐differences in incident AD rates decreased with increasing levels of education. The total contribution of the biomarkers to AD risk variance was 7.6% in women and 11.7% in men. One unit (pg/ml) lower plasma Aβ42 was associated with 0.0095 unit faster memory decline in women ( p = 0.0002) but not in men ( p = 0.55) after adjusting for age and education. Discussion Our study suggests that both early life and later‐life pathological factors may contribute to potential sex differences in incident AD.