Long Sleep Duration, Insomnia, and Insomnia With Short Objective Sleep Duration Are Independently Associated With Short Telomere Length.

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, = .044), insomnia disorder total sleep time < 360 minutes (OR = 4.205, 95% CI = 1.097-16.117, = .036) and long sleepers (OR = 2.177, 95% CI = 1.189- 3.987, = .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.