Health Related Quality of Life and Sleep Regularity Among Middle-Aged to Older Adults From the Community

Irregular sleep is increasingly related to poorer health, with stronger links to cardiovascular disease and mortality than sleep duration. Its impact on health-related quality of life, however, remains unclear, particularly in community-based populations. This study examined whether objectively measured sleep regularity is associated with physical and mental health-related quality of life. Sleep regularity was calculated using the Sleep Regularity Index from actigraphy data in 768 middle-aged to older adults from the Raine Study (median age [range] = 57 [53-61]; 58% female). Physical and mental health-related quality of life were assessed using the 12-item Short Form Health Survey. Quantile regression was used to examine associations at the 25th, 50th, and 75th percentiles, adjusting for age, sex, comorbidity count, sleep duration, and shift work. Median sleep regularity scores declined with self-rated health, from 77.17 (excellent) to 61.49 (poor). A 10-unit increase in sleep regularity was associated with higher mental health scores at the 25th (1.80; 95% CI: 0.90-2.60), 50th (1.20; 95% CI: 0.50-1.90), and 75th (0.50; 95% CI: 0.20-0.90) percentiles. For physical health, a 10-unit increase in sleep regularity was associated with a 1.20 (95% CI: 0.30-2.20) higher score at the 25th percentile, with no evidence of association at higher percentiles. These findings suggest that poorer sleep regularity is related to lower physical and mental health-related quality of life. Future research should explore whether improving sleep regularity can enhance quality of life in middle-aged to older adults.