Association of Sleep Duration and Quality With Alterations in the Hypothalamic-Pituitary Adrenocortical Axis: The Multi-Ethnic Study of Atherosclerosis (MESA).
Level 4 - case-series / case-control
Cross-sectional observational study
PubMed 26046965 · doi:10.1210/jc.2015-1198
What was done
Cross-sectional analysis of 600 participants aged 54–93 years from examination 5 (2010–2012) of the Multi-Ethnic Study of Atherosclerosis (MESA). Sleep duration and efficiency were measured using 7-day actigraphy alongside self-reported insomnia. Diurnal salivary cortisol samples were collected across 2 days to evaluate diurnal cortisol slopes and the awakening response.
What was found
- Average sleep duration <6 h/night was associated with a less pronounced late cortisol decline (2.2% difference in slope; 95% CI 0.8–3.7; P ≤ .01) and a less pronounced wake-to-bed slope (2.2% difference; 95% CI 1.0–3.4; P ≤ .001) compared with ≥6 h/night. - Lower sleep efficiency (<85%) was associated with a less pronounced early cortisol decline (29.0% difference in slope; 95% CI 4.1–59.7; P < .05) compared with ≥85% efficiency. - Participants reporting insomnia had a flatter cortisol awakening response (-16.1% difference in slope; 95% CI -34.6 to -0.1; P < .05) compared with those not reporting insomnia.
Why it matters
Shows that objectively measured short sleep duration, poor sleep efficiency, and insomnia relate to dysregulated diurnal hypothalamic-pituitary-adrenal axis activity in older adults, suggesting an endocrine mechanism linking poor sleep to cardiovascular outcomes.
Limits
Cross-sectional design cannot establish causality or determine the direction of the relationship between sleep alterations and cortisol dysregulation. Cortisol was sampled over only 2 days. The cohort consisted of older adults (aged 54–93 years), which may limit generalizability to younger populations.
Cited by
- supports A flattened diurnal cortisol curve predisposes individuals to insomnia and anxiety.