Takeaway
- Short sleep duration is associated with lower bone mineral density (BMD) and higher odds of osteoporosis in postmenopausal women.
Key results
- Compared with peers reporting sleeping 7 hours per night, women reporting sleeping ≤5 hours per night had lower adjusted BMD across sites:
- Whole body (β, −0.018 [95% CI, −0.025 to −0.011] g/cm2).
- Total hip (β, −0.015 [95% CI, −0.024 to −0.006] g/cm2).
- Femoral neck (β, –0.012 [95% CI, −0.019 to −0.004] g/cm2).
- Spine (β, −0.018 [95% CI, −0.029 to −0.006] g/cm2).
- Women reporting ≤5 hours per night had higher adjusted odds of:
- Low bone mass of hip (aOR, 1.22; 95% CI, 1.03-1.45).
- Osteoporosis of hip (aOR, 1.63; 95% CI, 1.15-2.31).
- Osteoporosis of spine (aOR, 1.28; 95% CI, 1.02-1.60).
- Sleep quality, assessed with insomnia rating scale, was not significantly associated with BMD.
Study design
- Cross-sectional cohort study of 11,084 postmenopausal women from Women’s Health Initiative (mean age, 63.3 years).
- Main outcomes: BMD of various sites; dual-energy X-ray absorptiometry–defined low bone mass (T-score <–2.5 to <–1), osteoporosis (T-score ≤–2.5).
- Funding: National Heart, Lung, and Blood Institute.
Limitations
- Self-reporting of sleep measures.
- Residual and unmeasured confounding.
- Unknown generalisability.
References
References