Relationship between sleep pattern and bone mineral density in patients with osteoporotic fracture

Associations of sleep behaviors and genetic risk with risk of incident osteoporosis: A prospective cohort study of 293,164 participants

BACKGROUND

Unhealthy sleep behaviors are associated with higher risks of osteoporosis (OP), while prospective evidence is limited. This study aimed to prospectively investigate this association, quantify the attributable burden of OP incidence reduction due to unhealthy sleep behaviors, and explore potential modifications by genetic risk factors.

METHODS

This longitudinal cohort study was conducted utilizing data from the UK Biobank, comprising 293,164 participants initially free of OP and with requisite sleep behaviors data at baseline. We followed the participants after recruitment until November 30, 2022, to ascertain incident OP. We assessed the associations of five sleep behaviors including sleep duration, chronotype, insomnia, daytime napping, and morning wake-up difficulties, as well as sleep behavior patterns identified based on the above sleep behaviors, with the risk of OP, using Cox models adjusted for multiple confounders. The analyses were then performed separately among individuals with different OP susceptibility, indexed by standard polygenetic risk scores(PRS) for OP. Our secondary outcome was OP with pathologic fracture. Subgroup and sensitivity analyses were performed. Additionally, attributable risk percent in the exposed population (AR%) and population attributable fraction (PAF) of sleep behaviors were calculated.

RESULTS

Over a median follow-up of 13.7 years, 8253 new-onset OP cases were documented. Unhealthy sleep behaviors, such as long or short sleep duration, insomnia, daytime napping, morning wake-up difficulties, and unhealthy sleep patterns, were associated with elevated risks of OP (HRs ranging from 1.14 to 1.46, all P-value <0.001) compared to healthy sleep behaviors. Similar associations were observed for OP with pathologic fractures. Insomnia exhibited the largest AR% of 39.98 % (95%CI: 36.46, 43.31) and PAF of 33.25 % (95%CI: 30.00, 36.34) among healthy sleep patterns and components. A statistically significant multiplicative interaction was noted between sleep behaviors and OP PRS on OP risk (all P-interaction <0.001).

CONCLUSIONS

Four unhealthy sleep behaviors and sleep behavior patterns were associated to increased OP risk, with insomnia contributing the most to OP incidence, while genetic risk for OP modified this association. These findings underscore the crucial role of adhering to healthy sleep behaviors for effective OP prevention.

Association Between Changes in Sleep, Nap Duration and Bone Mineral Density in Mexican Adults

Studies have found associations between sleep, nap duration, and bone mineral density (BMD). However, the longitudinal relationship between sleep, nap duration, and BMD has not been explored. We evaluated the association between the change in sleep and nap duration and BMD in Mexican adults. Data come from 1,337 adult participants of the Health Workers Cohort Study (341 were men and 996 were women, including 450 women < 45 years old and 546 ≥ 45 years old), with two study waves. At each wave, sleep and nap duration was assessed using self-administered questionnaires and BMD in g/cm2 was determined by dual X-ray absorptiometry. We used fixed-effect regression models stratified by sex and adjusted for BMI, diet, physical activity, vitamin supplements, and hormone replacement therapy. Women who changed from < 7 to ≥ 7 h/day of sleep from baseline to follow-up were associated with increases in the total hip (β = 0.012 g/cm2; 95% CI: 0.002, 0.022) and lumbar spine BMD (β = 0.024 g/cm2; 95% CI: 0.009, 0.039). Furthermore, most of these associations were observed in women ≥ 45 years. For women, a changing from 0 to > 60 min/day of napping was associated with a significant increase in total hip BMD of 0.012 g/cm2 (95% CI: 0.004, 0.024) and lumbar spine BMD of 0.027 g/cm2 (95% CI: 0.009, 0.045). No significant associations were observed for men. Our results suggest that increased sleep and nap duration are associated with gains in BMD in Mexican women, emphasizing sleep's role in promoting bone health and supporting established recommendations.

The joint effects of physical activity and sleep duration on risk of osteoporosis in Taiwanese adult population: The Taiwan Biobank Study

Most studies investigating the association between physical activity and osteoporosis prevention only focused on specific types of physical activity. This study's evidence regarding the combined effects or interaction of sleep duration and physical activity. The findings emphasize the role of sleep duration and physical activity in association with osteoporosis.

PURPOSE

The associations between physical activity, sleep duration, and prevalent osteoporosis in Taiwanese adults were studied in this cross-sectional study.

METHODS

The Taiwan Biobank enrolled a community-based cohort of ~ 120,000 volunteers (as of April 30, 2020) between 30 and 76 years of age with no history of cancer. Amongst, bone mineral density (BMD) measures by dual-energy X-ray absorptiometry (DXA) were available in 22,402 participants. After excluding individuals who had no complete data of BMI (n = 23), MET score (n = 207), T-score (n = 8,826), and sleep duration (n = 16), 13,330 subjects were included as the primary cohort. Univariate and multivariable regression analyses were performed to determine the associations between the presence of osteoporosis, physical activity level, sleep duration, and other variables.

RESULTS

The results showed that after adjustment, subjects with physical activity < 20 METs/week and ≥ 20 METs/week (aOR = 1.017 and 0.767, respectively) were associated with risk of osteoporosis than those with zero MET. The odds of osteoporosis were not significantly lower in subjects who slept for ≥ 8 h/day (aOR = 0.934,p=0.266). In addition, compared to short sleepers with no physical activity, adults with increased physical activity ≥ 20 METs/week and sleep ≥ 8 h/day had a significantly lowest likelihood of osteoporosis (aOR = 0.702). Those with medium physical activity (< 20 METs/week) plus average sleep duration (6.5-8 h/day) did not have significant higher odds of osteoporosis (aOR = 1.129,p=0.151).

CONCLUSION

The findings emphasize the joint role of sleep duration and physical activity in association with osteoporosis. Adults with high physical activity plus high sleep hours have the highest BMD and lowest risk of osteoporosis.

Sleep pattern in relation to recurrent osteoporotic fracture in the elderly

Background

Previous studies assessed the relationship between individual sleep behavior and fracture risk, rather than taking into account the joint complexity of the sleep behaviors. We aimed to explore the association between sleep pattern and risk of imminent recurrent osteoporotic fracture in older hospitalized patients due to an index osteoporotic fracture, where sleep pattern was evaluated as a combination incorporating five common sleep behaviors (i.e., insomnia, snoring, nocturnal sleep duration, daytime napping, and midnight waking up).

Methods

We used data from a prospective cohort study for analyses. Patients who aged not < 55 years and were admitted to the hospital due to an index osteoporotic fracture were recruited. Sleep pattern was grouped as healthy, intermediate, and poor pattern, based on the categorization of overall sleep scores. We used Cox proportional hazard models to explore sleep pattern in relation to imminent recurrent fracture.

Results

We included a total of 185 elderly hospitalized patients for analyses with mean (± standard deviation) age = 71.5 ± 10.3 years and 87.0% female. During a mean follow-up of 14.7 months, there were 10 (5.4%) recurrent osteoporotic fractures observed. A significantly higher overall sleep score was found in patients with recurrent fractures when compared with those without fractures (3.20 vs. 2.36, p = 0.038). Both intermediate (p = 0.76) and poor sleep patterns (p = 0.093) were non-significantly associated with an elevated risk of fracture when compared with a healthy pattern. Per-one-increase in the overall sleep score was significantly related to an increased risk of fracture: hazard ratio = 1.60 (95% confidence interval: 1.00--2.55) from the multivariable model.

Conclusion

Per-one-increase in the overall sleep score was found to be significantly associated with a 60% higher risk of imminent recurrent osteoporotic fracture in the elderly, and intermediate and poor sleep patterns were non-significantly related to an increased risk of recurrent fracture. More high-quality evidence is required to further evaluate the relationship between the sleep pattern and the risk of recurrent osteoporotic fracture in the elderly.

Association between bone turnover markers and the risk of imminent recurrent osteoporotic fracture

The association between bone turnover markers (BTMs) and the risk of imminent recurrent osteoporotic fracture (ROF) in the elderly remains unclear. The present study thus aimed to explore BTMs in relation to imminent ROF in the elderly with an index OF. For this purpose, data from a prospective cohort study were used for analysis. Elderly patients hospitalized due to an index OF were included and followed-up. The BTMs included bone resorption marker (C-terminal telopeptide of type I collagen) and the bone formation markers, procollagen type I N propeptide, osteocalcin (OC) and total alkaline phosphatase. The outcome was the time to the first ROF following their index fracture. Cox regression analysis was used to assess the association between BTMs and ROF. Model discrimination was calculated to explore whether the BTMs had potential to improve fracture risk prediction. There were 169 eligible patients included in the analysis (median age, 72 years; 87.6% females). During a median follow-up period of 10.5 months, there were seven ROFs (4.1%) observed. Serum OC levels were found to be significantly associated with the risk of ROF [hazard ratio, 0.13; 95% confidence interval (CI) 0.018-0.90; P=0.039] for per-SD increase in OC from multivariable analysis. After incorporating OC into the model, a C-index of 0.83 (95% CI, 0.70-0.96; P<0.001) was observed, which outperformed the model with bone mineral density alone (improvement for C-index, 0.29; 95% CI, 0.028-0.55). On the whole, the present study demonstrates a significant association between serum OC and the decreased risk of imminent ROF in the elderly with index fractures. However, further high-quality evidence is required to further clarify and validate the BTMs in relation to the imminent risk of ROFs among the elderly.