Sleep duration and timing in relation to osteoporosis in an elderly Chinese population: a cross-sectional analysis in the Dongfeng-Tongji cohort study

Sex- and Age-Specific Prevalence of Osteopenia and Osteoporosis: Sampling Survey

BACKGROUND

Osteopenia and osteoporosis are posing a long-term influence on the aging population's health contributing to a higher risk of mortality, loss of autonomy, hospitalization, and huge health system costs and social burden. Therefore, more pertinent data are needed to demonstrate the current state of osteoporosis.

OBJECTIVE

This sampling survey seeks to assess the trends in the prevalence of osteopenia and osteoporosis in a Chinese Han population.

METHODS

A community-based cross-sectional study involving 16,377 participants used a multistage sampling method. Bone mineral density was measured using the quantitative ultrasonic densitometry. Student t test and Mann-Whitney U test were used to test the difference between normally and nonnormally distributed quantitative variables between male and female participants. A chi-square (χ2) test was used to compare categorized variables. Stratified analysis was conducted to describe the prevalence rates of osteoporosis (T score ≤-2.5) and osteopenia (T score -2.5 to -1.0) across age, sex, calcium intake, and menopause. A direct standardization method was used to calculate the age-standardized prevalence rates of osteoporosis and osteopenia. T-score was further categorized into quartiles (T1-T4) by age- and sex-specified groups.

RESULTS

The prevalence rates of osteopenia and osteoporosis were 40.5% (6633/16,377) and 7.93% (1299/16,377), respectively, and the age-standardized prevalence rates were 27.32% (287,877,129.4/1,053,861,940) and 3.51% (36,974,582.3/1,053,861,940), respectively. There was an increase in osteopenia and osteoporosis prevalence from 21.47% (120/559) to 56.23% (754/1341) and 0.89% (5/559) to 17.23% (231/1341), respectively, as age increased from 18 years to 75 years old. The prevalence rates of osteopenia and osteoporosis were significantly higher in female participants (4238/9645, 43.94% and 1130/9645, 11.72%) than in male participants (2395/6732, 35.58% and 169/6732, 2.51%; P<.001), and in postmenopausal female participants (3638/7493, 48.55% and 1053/7493, 14.05%) than in premenopausal female participants (538/2026, 26.55% and 53/2026, 2.62%; P<.001). In addition, female participants with a history of calcium intake had a lower osteoporosis prevalence rate than female participants without any history of calcium intake in all age groups (P=.004). From low quartile to high quartile of T-score, the prevalence of diabetes mellitus (752/4037, 18.63%; 779/4029, 19.33%; 769/3894, 19.75%; and 869/3879, 22.4%) and dyslipidemia (2228/4036, 55.2%; 2304/4027, 57.21%; 2306/3891, 59.26%; and 2379/3878, 61.35%) were linearly increased (P<.001), while the prevalence of cancer (112/4037, 2.77%; 110/4029, 2.73%; 103/3894, 2.65%; and 77/3879, 1.99%) was decreased (P=.03).

CONCLUSIONS

Our data imply that as people age, osteopenia and osteoporosis are more common in females than in males, particularly in postmenopausal females than in premenopausal females, and bone mineral density significantly affects the prevalence of chronic diseases. These findings offer information that can be applied to intervention programs meant to prevent or lessen the burden of osteoporosis in China.

Association of nocturnal sleep duration and sleep midpoint with osteoporosis risk in rural adults: a large-scale cross-sectional study

BACKGROUND

Evidence has suggested the linkage between sleep habits and several metabolic diseases, but the association of sleep factors with bone health remains unclear, especially in regions with low economic levels. Thus, this study aimed to investigate the relationship of nocturnal sleep duration and sleep midpoint with the osteoporosis risk in a rural population.

METHOD

Eligible subjects were derived from the Henan Rural Cohort Study. The Pittsburgh Sleep Quality Index was applied to collect sleep information including sleep initiating time and wake-up time. The bone mineral density of the calcaneus was measured by the ultrasonic bone density apparatus. Multivariable logistic regression models and restricted cubic splines were utilized to evaluate the odds ratio (OR) and 95% confidence intervals (95% CI).

RESULTS

For 8033 participants, 1636 subjects suffered from osteoporosis. Compared with the reference group (7 ~ h group), the ORs and 95% CI of osteoporosis associated with duration of nocturnal sleep were 1.32 (1.10, 1.56), 1.59 (1.25, 2.01), and 1.82 (1.25, 2.65) in the 8 ~ h, 9 ~ h, and ≥ 10 h group, respectively. Additionally, the adjusted ORs and 95% CI were 1.20 (1.01, 1.44) in the early sleep midpoint group and 1.09 (0.92, 1.29) in the intermediate sleep midpoint, compared with the late. Furthermore, there was a joint effect of long duration of nocturnal sleep and the early sleep midpoint on osteoporosis.

CONCLUSION

Long duration of nocturnal sleep and early sleep midpoint were independently and jointly associated with higher risk of osteoporosis in rural areas.

TRIAL REGISTRATION

The Henan Rural Cohort Study has been registered at Chinese Clinical Trial Register (Registration number: ChiCTR-OOC-15006699). Date of registration: 06 July 2015. http://www.chictr.org.cn/showproj.aspx?proj=11375.

The Association Between Sleep Duration and Sleep-Related Gene Methylation with Osteoporosis in Chinese Postmenopausal Women

This study aims to investigate the association between sleep duration and osteoporosis. In addition, sleep-related gene methylation was also detected in this study and we explored its relationship with osteoporosis. The epidemiological investigation section of this study was designed as a retrospective cross-sectional study. We gathered 148 postmenopausal women from two communities and used questionnaires to collect data of sleep duration and other sleep patterns. Biochemical variables were tested, and bone mineral density was measured by dual-energy X-ray absorptiometry. In addition, sleep-related gene (PER2 and PER3) methylation was tested, and the association with osteoporosis was further studied. Twenty-nine of the 148 participants (aged from 65 to 86 years) who suffered from osteoporosis were tested for osteopenia. A significant difference was observed in the association between sleep duration and osteoporosis; the p-value was 0.013. In addition, in our study, we found that short sleep duration (<7 hours) may increase the risk of osteoporosis compared with longer sleep duration. Moreover, sleep-related genes such as PER2 and PER3 and their CpG island methylation were tested, and there was no significant difference between PER2 and PER3 CpG island methylation and osteoporosis. Short sleep duration may increase the risk of osteoporosis. However, the association between sleep-related gene methylation and osteoporosis was not found.

Associations of multiple plasma metals with osteoporosis: findings from the Dongfeng-Tongji cohort

With the aging population, osteoporosis has become a more prevalent public health issue. Existing researches have indicated significant relations of single metal exposure with osteoporosis (e.g., lead, copper, and zinc), whereas the evidence regarding the joint association of metal mixtures with osteoporosis remain limited and inconclusive. A total of 4924 participants from the Dongfeng-Tongji cohort were included in the present study. Plasma levels of 23 metals were determined by inductively coupled plasma mass spectrometry, and the presence of osteoporosis was defined as a bone mineral density T-score ≤  - 2.5. We applied stepwise regression, plasma metal score, and quantile g-computation model to evaluate the association between plasma metal mixtures and osteoporosis risk. Of the 4924 participants, the prevalence of osteoporosis was 10.9% (N = 265) in males and 27.5% (N = 684) in females. In the multiple-metals model, arsenic was positively associated with osteoporosis in males, while zinc was positively associated with osteoporosis in females. Comparing extreme quartiles, the multivariate-adjusted ORs of osteoporosis were 2.20 (95% CI, 1.29, 3.79; P-trend = 0.006) for arsenic in males and 2.16 (95% CI, 1.44, 3.23; P-trend < 0.001) for zinc in females. The plasma metal score was significantly and positively associated with a higher risk of osteoporosis, with ORs (95% CI) comparing extreme quartiles were 5.00 (95% CI, 3.36, 7.65; P-trend < 0.001) in males and 1.76 (95% CI, 1.35, 2.29; P-trend < 0.001) in females. Furthermore, the results of quantile g-computation revealed a consistent positive trend of metal mixtures with risk of osteoporosis and suggested the dominant role of arsenic in males and zinc in females, respectively. Our findings highlighted the importance of controlling metal mixtures exposure for the prevention of osteoporosis in the middle-aged and elder population. Further prospective studies in larger populations are warranted to confirm our findings.

Nocturnal sleep duration and bone mineral density: a cross-sectional study of the National Health and Nutrition Examination Survey (NHANES) 2007-2014

BACKGROUND

This study aimed to investigate the association between sleep duration and bone mineral density (BMD) and determine whether vitamin D (VD) status influenced the association between sleep duration and BMD.

METHODS

National Health and Nutrition Examination Survey 2007-2014 participants aged ≥ 40 years were included in this study. BMD testing was conducted with dual-energy X-ray absorptiometry examinations. Moreover, all individuals were divided into four groups according to self-reported nocturnal sleep duration (7-8 h; 6 h; < 6 h; and > 8 h). In addition, the differences in BMD between the normal sleep duration group and other groups were calculated using multiple linear regression models.

RESULTS

Overall, the median age of the overall study population was 55.00 years old, with 46.97% of men distributed. Participants sleeping > 8 h/night had lower BMDs than those sleeping 7-8 h/night. Moreover, the association between unhealthy sleep duration (especially > 8 h/night) and low BMD was more pronounced in older individuals, men, postmenopausal women, and subjects with inadequate VD intakes (< 15.00 µg/day) or deficient/insufficient serum 25-hydroxyvitamin D (< 75.00 nmol/L).

CONCLUSIONS

In conclusion, unhealthy sleep duration, especially long sleep duration, was associated with decreased BMD, particularly among individuals aged > 60 years, men, or postmenopausal women. Moreover, VD status might influence the association between sleep duration and BMD, especially in the context of inadequate VD intake or deficient/insufficient serum 25-hydroxyvitamin D levels. However, given the limitations of the present study, further investigation is warranted to confirm this association and to explore potential mechanisms.

Osteoporosis among Postmenopausal Women in Jordan: A National Cross-Sectional Study

Osteoporosis is considered a widespread health problem that affects senior citizens, particularly older women, after the menopause. This national study aimed to estimate the prevalence of osteoporosis among Jordanian postmenopausal women and to determine the association of demographic and nutritional factors, such as calcium and vitamin D supplement intake, with osteoporosis in postmenopausal women. A cross-sectional study was conducted among 884 postmenopausal women aged ≥50 years. A multistage sampling technique was used to select participants from three geographic regions of Jordan (north, middle, and south). The data were collected from the participants by a team of field researchers comprising men and women through a standard questionnaire. The prevalence of osteoporosis was 19.8% among postmenopausal Jordanian women. The study results showed that age (p ˂ 0.001), geographic region (p = 0.019), occupation (p = 0.002), and educational level (p = 0.001) were significantly associated with osteoporosis. Moreover, osteoporosis was significantly associated with calcium and vitamin D supplement intake (p < 0.05). There is a high prevalence of osteoporosis among postmenopausal Jordanian women. Therefore, there is a need to educate women at this age, and probably at an earlier age, to prevent or reduce the development of osteoporosis.

Association of Sleep Traits and Heel Bone Mineral Density: Observational and Mendelian Randomization Studies

Observational studies have suggested that sleep and circadian disturbances are potentially modifiable risk factors for low bone mineral density (BMD), but the causal relationship is unclear. This study aimed to (i) replicate the findings by examining observational association of sleep traits with low estimated BMD); (ii) examine whether these associations were causal by using Mendelian randomization (MR) analyses; and (iii) investigate potential modulation effects of sex and menopause. A total of 398,137 White British subjects (aged 39 to 73 years) with valid BMD estimated by quantitative ultrasound of the heel (eBMD) at baseline were included. Linear regression analyses and inverse-variance weighted method were used as main methods for observational and one-sample MR analyses, respectively, to investigate the associations between self-reported sleep traits (sleep duration, chronotype, daytime sleepiness, and insomnia) and low eBMD. Furthermore, sensitivity analyses were performed in subgroups based on sex and menopause in both observational and MR analyses. In observational analyses, short/long sleep, insomnia, and definite eveningness were associated with low eBMD (short sleep: β = -0.045, effect in standard deviation change of rank-based inverse normally transformed eBMD; long sleep: β = -0.028; sometimes insomnia: β = -0.012; usually insomnia: β = -0.021; definite eveningness: β = -0.047), whereas definite morningness was associated with decreased risk of low eBMD (β = 0.011). Subgroup analyses suggested associations of short/long sleep and definite eveningness with low eBMD among men, short sleep with low eBMD among premenopausal women, and short sleep, eveningness, and daytime sleepiness among postmenopausal women. In bidirectional MR analyses, there was no causal relationship between sleep traits and eBMD in either overall sample or subgroup analyses. In summary, although observational analysis showed a robust association of low eBMD with sleep duration, chronotype, and insomnia, there was no evidence of causal relationship as suggested by MR analysis. © 2021 American Society for Bone and Mineral Research (ASBMR).

Sleep pattern and bone mineral density: a cross-sectional study of National Health and Nutrition Examination Survey (NHANES) 2017-2018

This research is a cross-sectional study based on the participants aged 50 years and older from National Health and Nutrition Examination Survey (NHANES) database. Poor sleep patterns were associated with lower bone mineral density (BMD) and a higher risk of osteoporosis, especially among older individuals or females.

INTRODUCTION

Accumulated evidence demonstrates that sleep duration, which is one aspect of sleep pattern, is associated with the risk of osteoporosis. However, the related studies on the association between sleep patterns and the risk of osteoporosis were limited. Therefore, this research aims to investigate the association of sleep patterns with BMD and the risk of osteoporosis among individuals aged 50 years and older.

METHODS

Participants aged ≥ 50 years from the NHANES database were included in the present study. The diagnosis of osteoporosis was based on the results of BMD testing. Moreover, all the participants were divided into different sleep pattern groups according to nocturnal sleep duration and bedtime. In addition, this study used multivariate linear regression models to evaluate the association between sleep patterns and BMD and exploited multiple logistic regression models to investigate the odds ratios (ORs) for osteoporosis.

RESULTS

Finally, 1,865 individuals (non-osteoporosis: N = 1,713; osteoporosis: N = 152) aged over 50 years old with complete data were analyzed. The results of multivariate linear regression models showed that individuals with normal sleep duration/later bedtime or long sleep duration/later bedtime had lower femoral BMD than those with normal sleep duration/usual bedtime. Moreover, subjects with long sleep duration/later bedtime had a higher risk of osteoporosis compared with those with normal sleep duration/usual bedtime. In addition, subgroup analyses revealed the association of sleep patterns with BMD and the risk of osteoporosis appeared to be more pronounced among individuals aged ≥ 65 years or females.

CONCLUSION

This study demonstrated that sleep patterns are associated with BMD and the risk of osteoporosis. Poor sleep patterns contribute to decreased bone mass and the increased risk of osteoporosis. Therefore, a healthy sleep pattern is favorable for the prevention of osteoporosis.

Sleep disruptions and bone health: what do we know so far?

PURPOSE OF REVIEW

This review briefly summarizes the growing body of literature addressing the skeletal consequences of sleep and circadian disruption.

RECENT FINDINGS

The most recent data in the field suggest that the diurnal variation in bone turnover markers are because of endogenous circadian rhythmicity linked to clock genes in all bone cells; in a small human intervention study, cumulative sleep restriction with concurrent circadian disruption negatively alter bone turnover markers in a way that could explain the lower BMD and increased fracture risk identified in some prior night shift work studies; abnormal sleep duration and obstructive sleep apnea are associated with low BMD and increased fracture risk in some but not all studies.

SUMMARY

Normal physiology and some animal and human intervention studies suggest that sleep and circadian disruptions, such as night shift work, abnormal sleep durations and obstructive sleep apnea are detrimental to skeletal health. However, additional research in this area is needed to determine which sleep/circadian disturbances are most detrimental to skeletal health, the reversibility of such impairments, and underlying mechanisms.

A cross-sectional analysis of the association between sleep duration and osteoporosis risk in adults using 2005-2010 NHANES

Controversy remains regarding the relationship between bone health and sleep. In the literature, the effect of sleep on bone density in the clinical setting varies depending on the definition of normal sleep duration, sleep quality, selected population, and diagnostic tools for bone density. The aim of this study was to examine the association between bone mineral density (BMD)assessed by dual-energy X-ray absorptiometry and sleep duration/quality in the defined adult population from the National Health and Nutrition Examination Survey (NHANES) (a national household survey) within a 6-year period (2005–2010) and explore age differences. The basic variables, metabolic diseases, and bone density in the femoral neck as determined through dual-energy X-ray absorptiometry, were segregated, and analyzed according to different sleep durations (1–4, 5–6,7–8, and > 9 h/day) and sleep quality using multinomial regression models. A total of 12,793 subjects were analyzed. Our results reveal that women aged > 50 years with sleep duration < 5 h/day had a 7.35 (CI 3.438–15.715) odds of osteoporosis than those in other groups. This analysis is based on a nationally representative sample using survey and inspection data and clarifies the relationship between bone density and the effect of the combination of sleep quality and duration.

Sleep duration and bone health measures in older men

The associations between objective measures of sleep duration and bone outcomes in older men are unknown. No consistent, significant association was identified between sleep duration and bone mineral density (BMD) in the current analysis. However, future research should determine if vitamin D status modifies this relationship.

INTRODUCTION

Prior studies, predominantly in women, reported that long and short self-reported sleep duration are associated with lower BMD. Associations between actigraphy-determined sleep duration and BMD or bone turnover markers (BTMs) in older men are unknown.

METHODS

Men in The Osteoporotic Fractures in Men (MrOS) Study with wrist actigraphy and concurrent BMD assessment but without comorbidities affecting bone health were included. Sleep duration was considered as a continuous (N = 1926) and dichotomized variable where men were classified as getting the recommended (7-8 h/night; N = 478) or short (< 6 h/night; N = 577) sleep. The cross-sectional association between BMD, BTMs, and sleep duration was examined using a t test or linear regression, where appropriate, in unadjusted and adjusted models.

RESULTS

There were no clinically or statistically significant differences in BMD at the L-spine, total hip, or femoral neck between men getting the recommended vs. short sleep duration, using actigraphy or self-reported sleep duration (all p ≥ 0.07). When sleep duration was considered as a continuous variable, femoral neck BMD was higher in men with longer self-reported sleep duration (β = 0.006 ±0.003, p = 0.02), but this was not significant after further adjustment. In men with low 25OHD (< 20 ng/mL), longer actigraphy-determined sleep duration was associated with higher total hip BMD (β = 0.016 ± 0.008; p = 0.04). Sleep duration and BTMs were not associated.

CONCLUSION

Sleep duration was not associated with hip or L-spine BMD or BTMs in older men. Future research should determine if vitamin D status or other factors modify this relationship.

The mediating role of cognition in the relationship between sleep duration and instrumental activities of daily living disability among middle-aged and older Chinese

OBJECTIVE

To explore the effect of sleep duration at baseline on the incident IADL disability among middle-aged and older Chinese, and test whether cognition mediates this causality.

METHODS

Data were collected from wave 1 (2011-2012) to wave 3 (2015-2016) of the China Health and Retirement Longitudinal Study (CHARLS). Sleep duration was self-reported at baseline. Cognitive function, including episodic memory and mental intactness were measured via a questionnaire. IADL was assessed at baseline and follow-up. Baron and Kenny's causal steps and Karlson/Holm/Breen (KHB) method were conducted to examine the mediating effect.

RESULTS

A total of 10,328 participants free of IADL disability at baseline were included in this study. Over 4 years of follow-up, 17.1% of participants developed IADL disability. Compared to 7-8 h sleep duration, both short sleep (OR=1.460; 95% CI: 1.261-1.690 for sleeping ≤5 h; OR= 1.189; 95% CI: 1.011-1.400 for sleeping 5-7 h) and long sleep (OR=1.703; 95% CI: 1.269-2.286 for sleeping >9 h) were linked with incident IADL disability. KHB method identified significant mediating effect of cognition on the relationship between extreme sleep durations (≤5 h or >9 h) and IADL disability and the proportional mediation through cognition was 21.32% and 21.06% for sleeping ≤5 h and >9 h, respectively.

CONCLUSION

Both short (sleeping ≤5 h) and long sleep duration (sleeping >9 h) predicted incident IADL disability. Cognition partially mediated the effect of extreme sleep durations on IADL disability.

Self-reported Sleep Quality and Bone Outcomes in Older Adults: Findings from the Hertfordshire Cohort Study

Sleep duration may be associated with risk of osteoporosis, with suggestions that too little or indeed too much sleep may be detrimental to bone health. In this study, we considered whether perceived sleep quality is also associated with bone health in older adults. We explored this association in a cohort of 443 older community-dwelling UK adults. Sleep quality was assessed using the Pittsburgh Sleep Quality Index (PSQI); poor sleep quality was defined as > 5 on this score system. Bone density, shape and microarchitecture were assessed using dual energy X-ray absorptiometry (DXA), peripheral quantitative computed tomography (pQCT) and high-resolution pQCT (HRpQCT). Thirty-seven percent of men and 43% of women had a PSQI score greater than 5, indicative of poor perceived sleep. We found that quality of sleep was associated with altered bone microarchitecture. In men, poor sleep quality was associated with lower radial trabecular (4% slice, p < 0.04) and cortical (66% slice, p = 0.02) bone mineral density, as well as decreased tibial cortical density (p < 0.02) and increased porosity (p < 0.04), but increased size of the tibia (p < 0.04). In women, poor perceived sleep quality was associated with thinner (p < 0.03) and less dense (p < 0.04) cortices of the radius, but greater tibial trabecular number (p < 0.02) and lower separation (p < 0.04). Relationships with DXA parameters were non-significant after adjustment for confounders. Taking sleep medications was associated with decreased tibial size (38% and 66% slices) and strength in women (all p < 0.05), but not in men. Perceived sleep quality was associated with altered bone density and microarchitecture in older adults, and these differences varied according to biological sex and site. Further work is indicated to investigate possible mechanisms underlying these observations.

Methodological quality of cohort study on rheumatic diseases in China: A systematic review

Objective

To evaluate systematically the quality of the cohort studies on rheumatic diseases in China.

Methods

Relevant databases were searched to find cohort studies on rheumatic diseases in China, and the basic information included in the literature was extracted and analyzed. Chinese and English literature were then compared with regard to methodological quality, according to the Newcastle–Ottawa Scale (NOS).

Results

In total, we included 46 cohort studies, with 19 studies published in English and 27 studies published in Chinese. With regard to the basic characteristics of the literature, 78.26% of the studies were published in the past four years; 16 studies were associated with hyperuricemia, followed by eight studies involving systemic lupus erythematosus. The sample size of the studies in Chinese was lower than that in English studies (P< 0.05). The English literature was superior to the Chinese literature in terms of informed consent, ethical review and selection of statistical analysis methods. The methodology quality of the 46 included studies showed that the English and Chinese NOS scores were 5.59 ± 1.25 and 6.06 ± 1.11, respectively, and the difference was significant (P< 0.01). The “representativeness of the exposed group”, “demonstration that outcome of interest was not present at start of study”, and the “adequacy of follow up of cohorts” scores were relatively low in Chinese and English studies. The score for “was follow-up long enough for outcomes to occur” item in English was higher than that in the Chinese studies; however, the “study controls for the most important factor” score for Chinese papers was better than that for the English papers.

Conclusion

The Chinese rheumatic disease cohort studies started late, with a small sample size and fewer types of rheumatism. The quality of Chinese studies was better than English studies, and all reports were insufficient. In particular, “selecting exposed groups”, “controlling the outcomes before study implementation” and “adequacy of follow-up” needed improvement.

Long-term exposure to air pollution might increase prevalence of osteoporosis in Chinese rural population

OBJECTIVES

The associations of long-term exposure to air pollution with osteoporosis are rarely reported, especially in rural China. This study aimed to explore the association among rural Chinese population.

METHODS

A total of 8033 participants (18-79 years) derived from the Henan Rural Cohort Study (n = 39,259) were included in this cross-sectional study. Exposure to air pollutants was estimated using machine learning algorithms with satellite remote sensing, land use information, and meteorological data [including particulate matter with aerodynamic diameters ≤1.0 μm (PM₁), ≤2.5 μm (PM_2.5), and ≤10 μm (PM₁₀), and nitrogen dioxide (NO₂)]. The bone mineral density of each individual was measured by using ultrasonic bone density apparatus and osteoporosis was defined based on the T-score ≤ -2.5. Multiple logistic regression models were used to examine the association of air pollution and osteoporosis prevalence.

RESULTS

We observed that per 1 μg/m³ increase in PM₁, PM_2.5, PM₁₀ and NO₂ were associated with a 14.9%, 14.6%, 7.3%, and 16.5% elevated risk of osteoporosis. Compared with individuals in the first quartile, individuals in the fourth quartile had higher odds ratio (OR) of osteoporosis (P-trend < 0.001), the ORs (95% confidence interval) were 2.08 (1.72, 2.50) for PM₁, 2.28 (1.90, 2.74) for PM_2.5, 1.93 (1.60, 2.32) for PM₁₀, and 2.02 (1.68, 2.41) for NO₂. It was estimated that 20.29%-24.36% of osteoporosis cases could be attributable to air pollution in the rural population from China.

CONCLUSIONS

Long-term exposure to air pollutants were positively associated with high-risk of osteoporosis, indicated that improving air quality may be beneficial to improve rural residents health.

Gender-specific prevalence and influencing factors of osteopenia and osteoporosis in Chinese rural population: the Henan Rural Cohort Study

OBJECTIVE

The aims of this study were to describe distributions of the prevalence of osteopenia and osteoporosis and identify the potential risk factors by gender in a Chinese rural population.

DESIGN

A cross-sectional survey.

SETTING AND PARTICIPANTS

A total of 8475 participants (18-79 years) were obtained from the Henan Rural Cohort Study. Bone mineral density (BMD) of the calcaneus for each individual was measured by ultrasonic bone density apparatus. Logistic regression models were used to evaluate associations of potential risk factors with prevalence of osteopenia and osteoporosis. Furthermore, a meta-analysis of prevalence of osteoporosis which included eight studies was conducted to confirm this study results.

RESULTS

The mean of BMD were 0.42 and 0.32 g/cm² for men with osteopenia and osteoporosis (p<0.001), as well as 0.40 and 0.30 g/cm² (p<0.001) for women with osteopenia and osteoporosis, respectively. The overall age-standardised prevalence of osteopenia and osteoporosis were 42.09% and 11.76% in all participants. The age-standardised prevalence of osteopenia in men (45.98%) was significantly higher than that in women (39.73%), whereas the age-standardised prevalence of osteoporosis in men (7.82%) was lower than that in women (14.38%). Meta-analysis results displayed pooled prevalence of osteoporosis of 18.0% (10.1%-25.8%) in total sample, 7.7% (5.7%-9.7%) in men and 22.4% (17.1%-27.6%) in women. Multivariable logistic regression models showed that ageing, women, low education level or income, drinking or underweight was related to increased risk for osteopenia or osteoporosis.

CONCLUSIONS

About one-sixth of the participants suffered osteoporosis in rural China, and the prevalence in women was higher than men. Although the results were lower than that of meta-analysis, osteoporosis still accounts for huge burden of disease in rural population due to limited medical service and lack of health risk awareness rather than urban area.

TRIAL REGISTRATION NUMBER

Chinese Clinical Trial Registry (ChiCTR-OOC-15006699; Pre-results).

The associations between different sleep patterns and osteoporosis based on the Osteoporosis Self-Assessment Tool for Asians

Based on the use of Osteoporosis Self-Assessment Tool for Asians (OSTA) to assess osteoporosis risk, we found that short sleep duration and taking a daytime nap had an increased risk of osteoporosis.

PURPOSE

To explore the associations between different sleep patterns with osteoporosis.

METHODS

3659 postmenopausal women (average age of 60 years) were divided into low, middle, and high osteoporosis risk categories based on the Osteoporosis Self-Assessment Tool for Asians (OSTA). After having collected by a standard questionnaire, total and nocturnal sleep duration was collapsed to form categories of ≤ 6 h, > 6 h and ≤ 7 h, > 7 h and ≤ 8 h, > 8 h and ≤ 9 h, > 9 h, and daytime nap duration of 0 h and > 0 h.

RESULTS

As a categorical variable, the total sleep duration of ≤ 6 h per day (OR = 1.34, 95% CI 1.04-1.72), nocturnal sleep duration of ≤ 6 h per night (OR = 1.65, 95% CI 1.24-2.18), and taking a daytime nap (OR = 1.33, 95% CI 1.09-1.64) had higher osteoporosis risk after adjustment for covariates. As a continuous variable, after the adjustment for covariates, both longer total (OR = 0.86, 95% CI 0.78-0.94) and nocturnal sleep duration (OR = 0.83, 95% CI 0.76-0.91) had lower risk of osteoporosis risk while taking longer daytime nap (OR = 1.10, 95% CI 1.02-1.19) had higher osteoporosis risk.

CONCLUSIONS

Postmenopausal women with both short total and nocturnal sleep duration (6 h or less) and taking a daytime nap had increased osteoporosis risk as assessed by OSTA.

Association Between Late Bedtime and Diabetes Mellitus: A Large Community-Based Study

STUDY OBJECTIVES

The aim of this study was to investigate the association of bedtime with the prevalence of diabetes mellitus (DM) based on a large community-based population.

METHODS

In total, 5,420 participants (2,574 males and 2,846 females; aged 63.5 ± 11.0 years) from the Sleep Heart Health Study database were selected in this study. Sleep habit was recorded based on a questionnaire administered to patients upon recruitment. Bedtime was categorized as 11:00 pm and before, 11:00 pm to 12:00 am, and 12:00 am and later in the current study. Multivariate logistic regression was used to estimate the odds ratios (ORs) and 95% confidence intervals (CIs) to determine the relationship between bedtime and the prevalence of DM.

RESULTS

The distribution of weekday bedtime at 11:00 pm and before, 11:00 pm to 12:00 am, 12:00 am and later was observed in 3,316 participants (61.2%), 991 participants (18.3%), and 1,113 participants (20.5%), respectively. Meanwhile, individuals with weekday bedtime of 12:00 am and later had a higher prevalence of DM than those with bedtime at 11:00 pm to 12:00 am, and 11:00 pm and before (10.6% versus 5.7% versus 6.6%, respectively; P < .001). In the adjusted multivariate logistic regression model, bedtime at 12:00 am and later on a weekday was significantly associated DM prevalence (OR 1.446, 95% CI 1.107-1.888, P = .007). No significant association was found between weekend bedtime and DM.

CONCLUSION

Late bedtime at 12:00 am and later on a weekday may be a risk factor for the prevalence of DM. Stable sleep timing leads to lower risk of DM deserves future exploration.

Association between objective sleep duration and bone mineral density in older postmenopausal women from the Study of Osteoporotic Fractures (SOF)

Methodological limitations preclude determination of the association between sleep duration and bone mineral density (BMD) from existing literature. This was the first study to use objective sleep duration to determine its association with BMD. Nocturnal sleep duration, assessed objectively (actigraphy) or subjectively (questionnaire), was not independently associated with BMD in postmenopausal women.

INTRODUCTION

Both long and short self-reported sleep durations are associated with low bone mineral density (BMD) in men and women. The association between sleep duration measured by actigraphy and BMD in postmenopausal women is unknown.

METHODS

The Study of Osteoporotic Fractures (SOF) ancillary sleep study was used to determine the association between sleep duration and BMD at the total hip and femoral neck in postmenopausal women ≥ 75 years old. Sleep duration was assessed by wrist actigraphy (average 4 nights) and questionnaire. BMD was compared between postmenopausal women with short (< 6 h/night) vs. NIH-recommended (7-8 h/night) sleep durations. Data were analyzed using a 2-sample t test (unadjusted) and multivariate regression model (adjusted). Simple linear regression was used to estimate the difference in BMD per additional hour of sleep when sleep duration was considered as a continuous, rather than dichotomized, variable.

RESULTS

Total hip BMD was higher in women with actigraphically assessed shorter sleep duration in unadjusted models only. No clinically or statistically significant differences in total hip or femoral neck BMD were observed according to nocturnal sleep duration after adjusting for body mass index (BMI) in dichotomized (N = 874) or continuous (N = 1624) sleep duration models or when subjective sleep duration was used. When sleep duration included daytime naps, longer sleep duration was associated with lower total hip BMD (β = - 0.005, p = 0.04).

CONCLUSIONS

Nocturnal sleep duration, whether assessed objectively (actigraphy) or subjectively (questionnaire), was not independently associated with BMD in older postmenopausal women.

Lipid profiles as potential mediators linking body mass index to osteoporosis among Chinese adults: the Henan Rural Cohort Study

This study is to examine the relationship between body mass index (BMI) and osteoporosis in rural areas of China, and then explore whether this association was mediated by lipid profiles. Results showed that with the increasing of BMI, the risk of osteoporosis was reduced, and lipid profiles mediate this association.

INTRODUCTION

To examine the relationship between BMI and osteoporosis, and explore whether this association was mediated by lipid profiles.

METHODS

A total of 8272 participants (18-79 years) were enrolled from the Henan Rural Cohort Study. The bone mineral density of the calcaneus was measured using an ultrasonic bone density apparatus. Logistic regression and restricted cubic splines were used to evaluate the odds ratio (OR) and 95% confidence intervals (95% CI). Mediation analysis using bootstrap was performed to examine the contribution of lipid profiles to BMI-related osteoporosis.

RESULTS

The crude and age-standardized prevalence of osteoporosis were 15.93% and 11.77%, respectively. The mean BMIs were 24.12 kg/m² for participants with osteoporosis and 25.06 kg/m² for non-osteoporosis participants (P < 0.001). After adjusting for potential confounders, subjects with obesity had a lower OR of osteoporosis (0.493 [95% CI: 0.405-0.600], P_trend < 0.001) compared with normal-weight individuals. Mediation analysis showed that lipid profile partly mediated the relationship between BMI and osteoporosis with indirect effect OR (95% CI) of 0.985 (0.978-0.992), and the proportion explained of BMI was 15.48% for lipid profile.

CONCLUSION

With the increasing of BMI, the risk of osteoporosis was reduced in the Chinese adult population, and lipid profiles may be a potential mediator linking reduced risk of osteoporosis. Elucidating the underlying mechanisms will facilitate developing feasible preventive and therapeutic measures for osteoporosis. Chinese clinical trial register: ChiCTR-OOC-15006699.

Sleep-Disordered Breathing Is Associated with Reduced Mandibular Cortical Width in Children

INTRODUCTION

Evidence from the adult population suggests that sleep-disordered breathing (SDB) (i.e., obstructive sleep apnea [OSA]) is negatively associated with bone mineral density. Whether a similar association exists in children with SDB has not been investigated. Using the mandibular cortical width (MCW) as a proxy for skeletal bone density, we investigated if children at risk of SDB or diagnosed with OSA have a reduced mandibular cortical width compared to children without SDB.

METHODS

Two retrospective cross-sectional studies were performed. The first study included comparison of MCW between 24 children with polysomnographically (PSG) diagnosed OSA and 72 age- and sex-matched control children. The second study included a cohort of children in which SDB was suggested by the Pediatric Sleep Questionnaire (PSQ) ( n = 101). MCW was measured from panoramic radiographs.

RESULTS

Multiple-predictors regression analysis from the first study indicated that in children with a severe form of SDB, as induced by OSA severity, there was a negative association with MCW (β = -0.290, P = 0.049). Moreover, PSG-diagnosed OSA children had thinner MCW (2.9. ± 0.6mm) compared to healthy children (3.5 ± 0.6 mm; P = 0.002). These findings were further supported by the second study illustrating that PSQ total scores were negatively associated with MCW (β = -0.391, P < 0.001).

CONCLUSIONS

Findings suggest that children at risk for or diagnosed with SDB exhibit reduced mandibular cortical width that purportedly may reflect alterations in bone homeostasis.

KNOWLEDGE TRANSFER STATEMENT

We report that sleep-disordered breathing (including its severe form, obstructive sleep apnea) in children is associated with reduced mandibular cortical width. This association might be a direct consequence of reduced bone health to sleep-disordered breathing or a reflection that reduced bone formation underlies the development of sleep-disordered breathing. Our findings suggest that mandibular cortical width can be used as an adjunct diagnostic parameter for the diagnosis of sleep-disordered breathing.

Night shift work and osteoporosis: evidence and hypothesis

Osteoporosis is an important public health problem worldwide. Among the countries with a very high population risk of fractures, there are those with the highest level of economic development. Osteoporotic fractures are the main cause of disability among elderly people, and the resultant disabilities require particularly large financial support associated not only with the direct treatment of the fracture but also with the necessity for long-term rehabilitation and care for the disabled person. Many well-established factors can have impact on bone mass and fracture risk. Recently, it has been hypothesized that working during nighttime which leads to endocrine disorders may have an indirect impact on bone physiology among night shift workers. Therefore, it can be presumed that the night shift work may contribute to the etiology of osteoporosis. The aim of our work was to make a review of the epidemiological evidence on the association between night shift work and bone mineral density or fracture risk as well as to discuss the potential biological mechanisms linking the work under this system with the development of osteoporosis. We have identified only four studies investigating the association between system of work and bone mineral density or fracture risk among workers. The findings of three out of four studies support the hypothesis. None of the studies has investigated a potential relationship between night shift work and bone turnover markers. Given that there have been no epidemiological studies in European countries that would concern working populations and the noticeable difference in the risk of osteoporosis between communities, further studies are warranted to elucidate the problem. It is presumed that further in-depth studies will not only identify the underlying factors of the disease but also contribute to developing guidelines for policy makers and employers for primary prevention of osteoporosis in workplace.

Sleep onset latency is related with reduced bone mineral density in elderly people with insomnia: a retrospective study

Purpose

Inconsistent outcome about association between insufficient sleep and bone mineral density (BMD) has been reported. The present study aimed to determine whether BMD was associated with score of Pittsburgh Sleep Quality Index (PSQI).

Methods

A total of 410 patients (mean age 81.6±5.9 years) attending our hospital for evaluation of sleep were retrospectively studied. Dual-Energy X-ray Absorptiometry was used to measure BMD and T-score at femoral neck and lumbar spines over L2–L4 regions. Subjective sleep status was evaluated by the PSQI questionnaires. The Mann–Whitney U test and chi-square analysis were used to compare continuous variables and categorical variables, respectively. Spearman correlation test was conducted to find the relationship between BMD and other clinical factors. Multinomial logistic regressions analysis was performed to analyze independent factors predicting BMD.

Results

Majority of the participants with osteoporosis (OP) were female and had lower body mass index (BMI) and higher sleep onset latency score. Spearman correlation test showed that gender, BMI, score of total PSQI, and sleep onset latency were significantly related to BMD and T-score in femoral neck and lumbar region L2–L4. Finally, multinomial logistic regression analysis demonstrated that gender and age were independent factors for OP and osteopenia and that after adjustment for gender, age, and BMI, sleep onset latency of <15 minutes (OR: 0.38; 95% CI: 0.15–0.96; P=0.04) and 16–30 minutes (OR: 0.37; 95% CI: 0.17–0.79; P=0.01) were less likely to have reduced BMD.

Conclusion

There was a significant association between BMD and sleep onset latency, suggesting that, in elderly patients with sleep problem, BMD measurement and intervention for OP might be valuable.

Sleep duration and the risk of osteoporosis among middle-aged and elderly adults: a dose-response meta-analysis

It remains unclear how many hours of sleep are associated with the lowest risk of osteoporosis. This meta-analysis was performed to assess the dose-response relationship between sleep duration and risk of osteoporosis. PubMed and Web of Science were searched from inception to December 3, 2017, supplemented by manual searches of the bibliographies of retrieved articles. Data were pooled using fixed- and random-effects models. Restricted cubic spline analysis with four knots was used to model the sleep duration and osteoporosis association. Four cross-sectional studies with eight records were eligible for inclusion in the meta-analysis. A U-shaped dose-response relationship was observed between sleep duration and risk of osteoporosis, with the lowest risk observed at a sleep duration category of 8-9 h per day. Compared with 8-h sleep duration per day, the pooled odds ratio for osteoporosis were 1.03 (95% CI 1.01-1.06) for each 1-h reduction among individuals with shorter sleep duration and 1.01 (95% CI 1.00-1.02) for each 1-h increment among individuals with longer sleep duration. Our dose-response meta-analysis shows a U-shaped relationship between sleep duration and risk of osteoporosis, with the lowest osteoporosis risk at about 8 h per day of sleep duration. Both short and long sleep duration is associated with a significantly increased risk of osteoporosis in the middle-aged and elderly adults, appropriate sleep duration could help for delay or prevention of osteoporosis.

The importance of the circadian system & sleep for bone health

Adequate sleep timed appropriately during the circadian night is important for numerous biological processes and systems. New evidence suggests that both sleep timing and duration may be important for optimal bone health as well. This review examines the diurnal variation of bone turnover markers (BTMs) and the importance of circadian clock genes in regulating bone mass. In addition, this review explores the evidence for a link between shift work (and its associated disturbances in sleep duration/quality and circadian alignment) and alterations in bone metabolism and bone health. Finally, we review how commonly used medications and over-the-counter substances (e.g. caffeine, melatonin) complicate the relationship between sleep and circadian disorders and bone health.

Bone Turnover Markers After Sleep Restriction and Circadian Disruption: A Mechanism for Sleep-Related Bone Loss in Humans

CONTEXT

Sleep abnormalities are associated with low bone mineral density. Underlying mechanisms are unknown.

OBJECTIVE

Investigate the impact of sleep restriction with circadian disruption on bone biomarkers.

DESIGN

Intervention study.

PARTICIPANTS AND METHODS

Four bone biomarkers [C-terminal cross-linked telopeptide of type I collagen (CTX) = bone resorption, N-terminal propeptide of type I procollagen (P1NP) = bone formation, sclerostin and fibroblast growth factor 23 = osteocyte function] were measured in bihourly serum samples over 24 hours at baseline and after ∼3 weeks of sleep restriction (5.6 hours sleep/24 hours) with concurrent circadian disruption (recurring 28-hour "day" in dim light) in 10 men (age groups: 20 to 27 years, n = 6; 55 to 65 years, n = 4). The effects of sleep/circadian disruption and age on bone biomarker levels were evaluated using maximum likelihood estimation in a mixed model for repeated measures.

RESULTS

P1NP levels were lower after intervention compared with baseline (P < 0.001); the decrease in P1NP was greater for younger compared with older men (28.0% vs 18.2%, P < 0.001). There was no change in CTX (Δ = 0.03 ± 0.02 ng/mL, P = 0.10). Sclerostin levels were higher postintervention in the younger men only (Δ = 22.9% or 5.64 ± 1.10 pmol/L, P < 0.001).

CONCLUSIONS

These data suggest that 3 weeks of circadian disruption with concurrent sleep restriction can lead to an uncoupling of bone turnover wherein bone formation is decreased but bone resorption is unchanged. Circadian disruption and sleep restriction may be most detrimental to bone in early adulthood.

Associations of 24-hour sleep duration and CT-derived measurements of muscle and bone: The AGES-Reykjavik Study

BACKGROUND

Although the importance of sleep on preservation of several physiological functions is well known, the relationship with the two interconnected tissues - muscle and bone is less understood.

OBJECTIVES

This study aimed to examine the association of 24-hour sleep duration with mid-thigh muscle composition and proximal femur volumetric bone mineral density (vBMD).

METHODS

2438 men and 3326 women aged 66 to 96years, residents in the Reykjavik area, were included in this cross-sectional study. Proximal femur integral vBMD, mid-thigh muscle area and muscle attenuation were assessed with computed tomography. Sleep and nap habits were assessed using a questionnaire.

RESULTS

We found that after adjustment for age and BMI long sleep duration (>8h/d) was negatively associated with thigh lean area in both men (B=-2.21, 95% confidence interval (CI): -4.01, -0.40) and women (B=-2.39, 95% CI: -3.75, -1.03) and with muscle attenuation (B=-0.95, 95% CI: -1.47, -0.43) only in women. After adjustments for age, health and lifestyle factors the association between long sleep duration and muscle lean area was attenuated and became nonsignificant while associations with muscle attenuation remained marginally significant (B=-0.51, 95% CI: -1.03, -0.002). Sleep duration was not associated with proximal femur integral vBMD in the multivariate models.

CONCLUSION

Long sleep duration, particularly in old women, can affect thigh muscle attenuation (increase in intramuscular fat). Whether optimization of sleep can ameliorate age-associated intramuscular or intermuscular adipose tissue warrants further studies.

Association between sleep duration and osteoporosis risk in middle-aged and elderly women: A systematic review and meta-analysis of observational studies

OBJECTIVE

Increasing evidence has suggested an association between sleep duration and osteoporosis risk, although the results of previous studies have been inconsistent. To our knowledge, this is the first meta-analysis of the literature and quantitative estimates of the association between sleep duration and risk of osteoporosis in population-based studies of middle aged and elderly women.

METHODS

Pertinent studies were identified by searching PubMed and EMBASE databases up to February 2016. Five out of six included studies were cross-sectional and one was a prospective cohort study. They included 72,326 participants from three different countries. We extracted 31,625 individuals in these studies for our meta-analysis.

RESULTS

A pooled odds ratio analysis in women between 40 to 86years indicated that there is an inverse relationship between sleep duration and osteoporosis (overall OR =1.07 95% CI: 1.00-1.15). The negative association of long sleep duration (8h or more per day) with osteoporosis risk was observed in middle aged and elderly women (OR =1.22, 95% CI: 1.06-1.38) but not in women with short sleep duration (7h or less per day) (OR =0.98, 95% CI: 0.90-1.05).

CONCLUSION

This meta-analysis suggests that long sleep duration (8h or more per day) may be associated with a higher risk of osteoporosis in middle-aged and elderly. Further prospective cohort studies with longer follow-up periods, valid instruments for measurement of sleep duration and dynamic sleep quality are warranted to support the possible relationship between sleep duration and osteoporosis risk in women.

Does Subjective Sleep Affect Bone Mineral Density in Older People with Minimal Health Disorders? The PROOF Cohort

STUDY OBJECTIVES

Clinical and epidemiological studies suggest a relation between bone mineral density (BMD) and self-assessment of sleep with an effect on bone formation and osteoporosis (OS) risk in short and long sleepers. This study explores this association in a large sample of older subjects.

METHODS

We examined 500 participants without insomnia complaints aged 65.7 ± 0.8 y. Each participant had a full evaluation including anthropometric measurement, clinical examination and measurements of BMD at the lumbar spine and femoral sites by dual-energy X-ray absorptiometry. The daily energy expenditure (DEE) was measured by the Population Physical Activity Questionnaire. Sleep duration and quality were evaluated by the Pittsburgh Sleep Quality Index. The subjects were stratified into three groups according to sleep duration, i.e., short (< 6 h), normal (6-8 h), and long (≥ 8 h) sleepers.

RESULTS

Osteopenia was found in 40% of the subjects at the femoral level and 43% at the vertebral level. The prevalence of OS was lower both at femoral (8%) and vertebral (12%) levels. Short, normal, and long sleepers accounted for 29%, 40%, and 31% of subjects, respectively. After adjustments for metabolic, anthropometric, and DEE, multinomial logistic regression analysis indicated that long sleepers were more likely to have femoral neck OS with a slight effect of DEE at vertebral spine.

CONCLUSIONS

In a sample of older subjects, self-reported long sleep was the best predictor of OS risk at the femoral level. This finding suggests an association between OS and self-reported sleep duration in older subjects.

CLINICAL TRIAL REGISTRATION

NCT 00759304 and NCT 00766584.

Impact of sleep on osteoporosis: sleep quality is associated with bone stiffness index

OBJECTIVE

The aim of the present study was to investigate the impact of sleep on osteoporosis.

METHODS

The study used a baseline examination of the Hiroshima Sleep and Healthcare study, which was a cross-sectional and cohort study that addressed the association of sleep habits with lifestyle-related diseases. A total of 1032 participants (25-85 years of age) who underwent health examinations were included. Sleep habits, including its timing (bed time), quantity (time in bed [TIB]), and quality, were assessed using the Pittsburgh Sleep Quality Index (PSQI). The bone stiffness index (SI), a marker of osteoporosis, was measured using quantitative ultrasound systems.

RESULTS

Bed time (r = 0.065, p <0.05), TIB (r = -0.064, p <0.05), and global PSQI score (r = -0.126, p <0.0001) significantly correlated with SI. Multiple regression analyses revealed that after adjusting for age, sex, body mass index, smoking, and alcohol intake, the global PSQI score (β = -0.053, p <0.05) was significantly associated with SI, whereas bed time or TIB was not. Among each component of PSQI, sleep disturbances (β = -0.084, p <0.005) were significantly associated with SI.

CONCLUSION

Poor sleep quality may be associated with osteoporosis. In particular, increased sleep disturbances may be a key factor in the association between poor sleep quality and osteoporosis.