Shorter sleep duration is associated with lower bone mineral density (BMD) and a higher risk for osteoporosis in postmenopausal women, according to study results published in the Journal of Bone and Mineral Research.
The study included postmenopausal women from the Women’s Health Initiative (N=11,084). The researchers used linear regression models to determine the association between self-reported usual hours of sleep and sleep quality (measured by the Women’s Health Initiative Insomnia Rating Score) and BMD measures at the whole body, total hip, femoral neck, and spine. They used multinomial regression models to examine associations between sleep duration and quality with dual-energy x-ray absorptiometry (DXA)-defined low bone mass (T-score >-2.5 to <-1) and osteoporosis (T-score ≤-2.5).
The results were adjusted for age, DXA machine, race, menopausal symptoms, education, smoking, physical activity, body mass index, alcohol use, physical function, and sleep medication use.
The researchers found that women who reported sleeping ≤5 hours per night had significantly lower BMD at all 4 sites (average difference, -0.012 to -0.018 g/cm2) compared with women who reported sleeping 7 hours per night.
Adjusted multinomial models indicated that women who reported ≤5 hours of sleep per night had increased odds of having low bone mass (odds ratio [OR], 1.22; 95% CI, 1.03-1.45) and osteoporosis at the hip (OR, 1.63; 95% CI, 1.15-2.31). In a similar fashion, women who slept ≤5 hours per night had an increased risk for osteoporosis at the spine (OR, 1.28; 95% CI, 1.02-1.60).
The researchers did not find any significant associations between sleep quality and DXA-measured BMD.
“[W]e have provided epidemiologic evidence into sleep as a partially modifiable risk factor for BMD that is deserving of further replication and mechanistic studies,” wrote the researchers. “If studies show that sleep duration has a causal link with bone density, sleep promotion interventions may serve as a way to mitigate bone loss in individuals at high risk of osteoporosis.”
Disclosure: One study author declared affiliations with the pharmaceutical industry. Please see the original reference for a full list of authors’ disclosures.
Reference
Ochs-Balcom HM, Hovey KM, Andrews C, et al. Short sleep is associated with low bone mineral density and osteoporosis in the Women’s Health Initiative [published online November 6, 2019]. J Bone Miner Res. doi:10.1002/jbmr.3879
