Long sleep duration is associated with incident sarcopenia after two years in community- dwelling older men

Abstract Background: Sarcopenia, a progressive and generalized skeletal muscle disorder involving accelerated loss of muscle mass and muscle function, is a common condition in older individuals. This study aims to determine whether sleep latency and duration are independently associated with incident sarcopenia and to explore sex differences in these associations.Methods: A two-year longitudinal analysis of cohort study data was conducted. The sample was 70-84 years old community-dwelling participants in the Korea Frailty and Aging Cohort Study at baseline survey in 2016-2017 who completed the follow-up survey after 2 years. Logistic regression was used to calculate odds ratios (OR) for sarcopenia and sarcopenia components. Sarcopenia was defined using the 2019 Asian Working Group for Sarcopenia guidelines.Results: Among 1,353 non-sarcopenic participants in the baseline survey, 1,160 participants were classified as non-sarcopenic (85.8%) and 193(14.2%) as sarcopenic after 2 years. Long sleep duration (> 8 hours per night) was associated with incident sarcopenia in men (OR = 2.410 (95% confidence interval [CI] 1.125-5.166) after adjusting for confounding factors). Long sleep duration was specifically associated with development of low skeletal muscle mass and low muscle strength in men; adjusted ORs were 2.163 (95% CI 1.016-4.605) and 2.695 (95% CI 1.130-6.431), respectively. There was no significant association between sleep latency and sarcopenia in men (OR 1.014; 95% CI 0.505-2.036). For women, long sleep duration (OR 2.093; 95% CI 0.753-5.812) and sleep latency (OR 0.674; 95% CI 0.351-1.296) were not associated with sarcopenia.Conclusion: In men, long sleep duration was associated with incident sarcopenia, specifically the development of low muscle mass and low muscle strength, but not with low gait speed. In contrast, there was no such association for women.