Long sleep duration, insomnia, and insomnia with short objective sleep duration are independently associated with short telomere length

Abstract

Study Objectives: We aimed to determine the association between short telomere length, sleep parameters, and sleep disorders in an adult general population sample. Methods: As part of the EPISONO cohort (São Paulo, Brazil), 925 individuals answered questionnaires, underwent a full-night polysomnography and clinical assessment, and had peripheral blood collected for DNA extraction. Insomnia was diagnosed based on the Diagnostic and Statistical Manual of Mental Disorders, 4th edition; and obstructive sleep apnea was defined according to apnea-hypopnea index. For the objective insomnia phenotype, we combined insomnia diagnosis with total sleep time from polysomnography with a cutoff of 360 minutes, allowing the classification of six groups. Self-reported sleep duration was used to classify the individuals as short (< 6 hours), average (6 to 8 hours) and long (> 8 hours) sleepers. The leukocyte telomere length was measured using quantitative real-time polymerase chain reaction. Based on its distribution, we considered leukocyte telomere length < 10th percentile as short telomere and leukocyte telomere length ≥ 10th percentile as non-short telomere. Results: After adjusting for sex, age, and body mass index, only insomnia disorder (odds ratio [OR] = 2.654, 95% confidence interval [CI] = 1.025-6.873, P =.044), insomnia disorder total sleep time < 360 minutes (OR = 4.205, 95% CI = 1.097-16.117, P =.036) and long sleepers (OR = 2.177, 95% CI = 1.189-3. 987, P =.012) were associated with short telomere. Conclusions: Our findings support the existence of an association among insomnia, insomnia phenotype, and self-reported long sleep duration with the maintenance of telomere length. Commentary: A commentary on this article appears in this issue on page 1975.