Sleep Quality, Duration Affect Risk for Falls and Fractures in Older Women
Sleep duration and quality may affect bone metabolism in several ways, including disturbed rhythm of bone turnover and inflammation.
According to study results published in the Journal of Bone and Mineral Research, women who sleep poorly might be more likely to experience recurrent falls and bone fractures.
Researchers conducted this prospective study of 157,306 individuals in the Women's Health Initiative to investigate the association between self-reported sleep and falls and fractures. Data for each participant were collected for an average of 7.6 years for falls and 12 years for bone fractures. Information on sleep quality and duration were collected on baseline questionnaires.
Of the total population, 37% reported sleeping on average 7 hours/night; 8.3% slept an average of ≤5 hours and 4.4% slept an average of ≥9 hours. Women who slept ≤5 hours were more likely to experience restless sleep, trouble falling asleep and waking, and insomnia.
Compared with women who averaged 7 to 8 hours of sleep, women who slept ≤5 hours were 27% more likely to experience recurrent falls and women who slept ≥10 hours were 24% more likely to experience falls. Very restless sleepers were 21% more likely to report recurrent falls than women who reported average sleep quality, and women with the greatest sleep disturbance level were 34% more likely to report recurrent falls compared with women who had the fewest sleep disturbances.
Furthermore, the researchers reported that women who were short sleepers were significantly more likely to experience fractures than those who reported average sleep duration (hazard ratios, 1.10-1.13; P <.05). There was, however, no association between fractures and long duration of sleep. Compared with women who reported the lowest sleep disturbance, participants who reported the highest levels of sleep disturbance were 22% to 36% more likely to experience fractures.
Several limitations were noted for this study, including its reliance on self-reported data for falling and fracture statistics.
“There are several suggestive findings of an association between sleep characteristics and fractures that are consistent with our modest associations,” the researchers said. “Given the widespread prevalence of sleep disorders in the population, more information is needed on whether sleep influences the risk [for] fracture.”
Cauley JA, Hovey KM, Stone KL, et al. Characteristics of self-reported sleep and the risk of falls and fractures: the Women's Health Initiative (WHI) [published online November 21, 2018]. J Bone Miner Res. doi:10.1002/jbmr.3619