Lu Chen

Background Sleep duration is an important component of healthy aging, yet gender differences in short and long sleep among older adults remain insufficiently understood. This study aimed to examine gender differences in sleep duration among Chinese older adults and quantify the contributions of socioeconomic, behavioral, functional, and health-related factors to these differences. Methods Data were obtained from 9,590 adults aged ≥65 years who participated in the 2018 wave of the Chinese Longitudinal Healthy Longevity Survey. Sleep duration was self-reported and categorized as short (<6 h), normal (6–8 h), or long (>8 h). Multinomial logistic regression was used to identify factors associated with short and long sleep, with weighted analyses and Poisson regression performed as sensitivity analyses. Separate Fairlie decomposition analyses were conducted for short and long sleep to quantify the contributions of observed characteristics to gender differences. Results Overall, 44.95% of participants had abnormal sleep duration, with a higher prevalence among women than men (46.87% vs. 42.66%, p < 0.001). Compared with men, women had a higher relative risk of short sleep (RRR = 1.399, 95% CI: 1.204–1.625) but a lower relative risk of long sleep (RRR = 0.856, 95% CI: 0.754–0.972). The association with short sleep remained significant in the weighted analysis (RRR = 1.530, 95% CI: 1.210–1.935), whereas the gender difference in long sleep was attenuated (RRR = 0.821, 95% CI: 0.661–1.021). For short sleep, observed characteristics explained 21.65% of the gender disparity. Education (22.75%), depressive symptoms (11.07%), IADL limitation (6.02%), and self-assessed health (4.82%) contributed positively to the disparity, whereas smoking status (−22.57%), drinking status (−12.45%), and exercise (−4.87%) partially offset it. The gender difference in long sleep was negligible, with substantial offsetting contributions across factors. Conclusion Gender differences in sleep duration among Chinese older adults were primarily concentrated in short sleep, with women experiencing a higher risk. Socioeconomic, behavioral, psychological, and functional characteristics contributed to this disparity, although most of the short-sleep difference remained unexplained. Gender-sensitive interventions addressing educational disadvantage, depressive symptoms, functional limitations, and health behaviors may help reduce inequalities in sleep duration among older adults.