Age-related changes in sleep architecture: Effects of body mass index, sex, and mental health in community-dwelling adults using at-home polysomnography

Background: Sleep is a critical component of human health, influencing cognitive, physical, and psychological well-being. Sleep architecture changes significantly with age. Odds Ratio Product (ORP) is a novel continuous index of sleep depth, which provides insights into age-related changes in sleep depth. Objectives: This study investigates the interaction of sex, body mass index (BMI) and mental on age-related changes in sleep architecture, measured with ORP in community-dwelling adults using at-home polysomnography (PSG). Methods: We measured sleep architecture using ORP in 195 middle-aged to older (>50 years) sedentary but healthy adults and a younger cohort (<35 years, n = 34). All sleep nights utilized MY scoring (Cerebra Medical, Winnipeg Manitoba) to calculate traditional sleep architecture values, average ORP in different sleep stages and percent of time in different ORP deciles. Differences between groups were assessed using ANOVA models. Mental health was assessed using standardized questionnaires linear regression models were used to report the relationship between age and sleep architecture, ORP, and interactions between sex, BMI, anxiety and depression. Results: Significant interactions were present for body mass index, deep sleep deciles, and the awake stage. Conclusions: Confirming previous findings, we report reduced deep sleep, increased light sleep and more full wakefulness in middle-aged to older adults, consistent with decreased sleep pressure with aging. Higher body mass index was associated with reduced age-related changes in sleep architecture.