Sleep Quality and Duration as Determinants of Healthy Aging Trajectories: The HELIAD Study.

Background: The aging of global population has increased the scientific interest in the concept of healthy aging and its determinants.

Aim: The aim of this study was to investigate the association of sleep characteristics with trajectories of healthy aging.

Design And Setting: Prospective observational study conducted in two cities, Maroussi and Larissa.

Participants: A total of 1226 older adults (≥65 years, 704 women) were selected through random sampling.

Measurements: Sleep quality was assessed with the Sleep Index II, and sleep duration was self-reported. A healthy aging metric was introduced using an Item Response Theory approach based on validated questionnaires that assessed functionality. Four healthy aging trajectories were developed based on whether the healthy aging status of the participants was above (High) or below (Low) the median at baseline and follow-up, i.e., High-High, High-Low, Low-High, and Low-Low. The association of sleep characteristics with the trajectories was investigated using a multinomial logistic regression with the Low-Low group as reference, adjusting for potential confounders.

Results: 34.3% participants classified to the High-High group, 15.7% to the High-Low, 18.6% to the Low-High, and 31.4% to the Low-Low group. Better sleep quality was associated with the probability of belonging to the High-High group (p-value<0.001); while, long sleep duration was inversely associated with likelihood of being classified in the High-High group (p-value < 0.05).

Conclusion: Poor sleep quality and long sleep duration seem to have a significant negative association with healthy aging. Public health policies are needed to raise awareness about the importance of sleep characteristics on human health.