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

Association between life's essential 8 and bone mineral density among adults aged 20-59 years

This study investigates the relationship between Life's Essential 8 (LE8) scores and bone mineral density (BMD) in adults aged 20-59 years. This cross-sectional analysis employed nationally representative data from NHANES 2011-2018. Weighted multiple linear regression models were applied to assess the association between LE8 scores and varying levels of cardiovascular health (CVH) with BMD. Subgroup analyses were performed to evaluate differences in the impact of LE8 scores on BMD across age groups, genders, races, socioeconomic statuses, and BMI categories. The study included 2159 participants. After adjusting for all covariates, LE8 scores demonstrated a significant positive linear association with lumbar spine BMD, thoracic spine BMD, trunk BMD, and total BMD. Individuals in the medium and high CVH groups exhibited higher BMD compared to those in the low CVH group. Subgroup analyses indicated that the association was more evident in participants aged 20-35 years and among those with normal BMI. In females, thoracic spine BMD appeared particularly sensitive to changes in LE8 scores. This study identifies a positive linear relationship between LE8 scores and BMD. Higher CVH scores were linked to greater BMD in adults aged 20-59 years. These findings highlight the importance of adopting comprehensive health strategies, suggesting that improving CVH may contribute to maintaining bone density and supporting skeletal health.

Association of caffeine intake and sleep duration with bone mineral density: a cross-sectional study from National Health and Nutrition Examination Survey between 2011 and 2018

OBJECTIVE

The association between sleep duration, caffeine intake, and bone mineral density (BMD) is not well understood, with previous studies providing controversial results. This study explores the associations among caffeine intake, sleep duration, and BMD.

METHODS

Data were sourced from the National Health and Nutrition Examination Survey (NHANES) from 2011 to 2018, including 13,457 participants who self-reported sleep duration and caffeine intake, with BMD measured via dual X-ray absorptiometry. Multivariable linear regression models, adjusted for confounders, were used alongside restricted cubic splines to examine dose-response association.

RESULTS

Of all participants, 6821 (50.7%) were males and 6636 were females (49.3%). The mean caffeine intake and sleep duration were 93.4 mg/day and 7.19 h, respectively. RCS results showed that BMD increased with the increase in caffeine intake, especially in the low dose range of 0-200 mg/day. The dose-response association between sleep duration and BMD showed that sleep durations of 0-6 h may promote the increase of BMD, but after sleep durations greater than 6 h, BMD decreases. After adjustment for potential confounders, compared to the lowest referent quartile, individuals with caffeine intake in quartiles 2, 3, and 4 had a positive correlation with BMD (0.62 95% CI: 0.24-1.37; 0.51 95% CI: 0.22-1.13; 0.75 95% CI: 0.41-1.46; P for trend < 0.05). In covariate-adjusted linear regression models, compared with those sleeping 6 h or less per night, the difference in BMD among those sleeping 6-7 h, 7-8 h, and 8-14.5 h per night were 1.81 (95% CI: 0.4122.71), 1.25 (95% CI: 0.55-2.93), and 0.87 (95% CI: 0.38-1.69). Associations of caffeine intake, sleep duration, and BMD stratified by sex and age failed to reach statistical significance.

CONCLUSIONS

Association might exist between the consumption of caffeine, sleep duration, and BMD; however, when stratified by sex and age, the association did not reach statistical significance.

24-hour activity composition is associated with lower fall and fracture risk in older men

Physical activity (PA), sedentary behavior (SB), and sleep are each individually associated with falls and fractures, but often are not examined simultaneously. Compositional data analysis examined the combined prospective associations between the proportion of time in PA, SB, and sleep relative to the remaining behaviors with recurrent falls (2+ falls in any yr), any fractures, and major osteoporotic fracture (MOF) from tri-annual questionnaires, with adjudication for fractures, in 2918 older men aged 78.9 ± 5.1 yr in the Osteoporotic Fractures in Men (MrOS) Study. Accelerometers were worn on the right tricep for seven consecutive 24-h periods and measured PA (>1.5 METs), SB (≤1.5 METs), and sleep. Generalized estimating equations evaluated associations with recurrent falls. Cox proportional hazards regression estimated any incident fracture and MOF risk separately. Over 4 yr of follow-up, 1025 (35.2%) experienced recurrent falls; over 10 ± 4 yr of follow-up, 669 (22.9%) experienced incident fractures, and 370 (12.7%) experienced a MOF. Higher proportions of PA relative to SB and sleep were associated with lower odds of recurrent falls [odds ratio (OR): 0.87, 95% CI: 0.76-0.99]. Higher proportions of SB relative to PA and sleep were associated with a higher odds of recurrent falls (OR: 1.38, 95% CI: 1.06-1.81) and a higher risk of any fracture [hazard ratio (HR): 1.42, 95% CI: 1.05-1.92]. Higher proportions of sleep relative to PA and SB were associated with a lower risk of fracture (HR: 0.74, 95% CI: 0.54-0.99). No associations of activity composition with MOF were observed. When accounting for the co-dependence of daily activities, higher proportions of SB relative to the proportion of PA and sleep were associated with higher odds of recurrent falls and fracture risk. Results suggest reducing SB (and increasing PA) may lower fall and fracture risk in older men, which could inform future interventions.

Influence of sedentary behavior and physical activity in leisure and work on sleep duration: data from NHANES 2017-2018

OBJECTIVE

To evaluate the association between sedentary behavior (SB), moderate to vigorous physical activity (MVPA), and sleep duration.

METHODS

Data from the 2017-2018 National Health and Nutrition Examination Survey (NHANES) was analyzed. SB was assessed based on the average daily sitting time, while MVPA was estimated by the frequency and duration of leisure and work-related activities. The ratio of time spent in MVPA to time in SB was analyzed, and a thresholds of ≥ 1.0, 2.5 and 10 min of MVPA per sedentary hour was used to determine sufficiency for mitigating the effects of a sedentary lifestyle. Sleep duration was measured by the average hours slept on weekdays and weekends, classified according to National Sleep Foundation guidelines. The measures of SB, MVPA, and sleep were self-reported. Descriptive statistics were used to characterize the sample, and multivariate logistic regression was applied to assess the associations between movement behaviors and sleep duration.

RESULTS

The study included 5,533 participants, with 51.8% women, predominantly aged 26-64 years (66.1%). Insufficient physical activity was reported by 59.6% at work and 62.5% during leisure time. Recommended sleep duration was observed in 84.4% of the sample. Adjusted multivariate analysis revealed that individuals engaging in ≥ 2.5 min of MVPA during leisure-time for each sedentary hour were 38.9% less likely to experience short-term sleep (OR:0.72;95%CI:0.53-0.97). Conversely, those who performed the same amount of MVPA at work were 57.0% more likely to have short-term sleep (OR:1.57;95%CI:1.16-2.12).

CONCLUSION

Meeting the MVPA threshold during leisure-time reduces the likelihood of short-term sleep, while higher MVPA levels at work increase the likelihood of short-term sleep.

Associations between life's essential 8 and femoral neck bone mineral density among adults: A national population-based study

Osteoporosis represents a significant public health issue, impacting both health outcomes and economic costs. This research investigates how cardiovascular health, as indicated by the LE8 score, correlates with bone mineral density (BMD). Data from the National Health and Nutrition Examination Survey (NHANES) spanning 2011 to 2018 were analyzed in this cross-sectional analysis, including 9018 subjects following the exclusion of individuals lacking BMD or LE8 data. The LE8 score, comprising factors such as diet, physical activity, smoking status, sleep quality, body mass index, lipid profiles, blood glucose, and blood pressure, was used to evaluate cardiovascular health. BMD was determined through dual-energy X-ray absorptiometry (DXA). Relationships between the LE8 scores and BMD at the femoral neck were assessed using linear regression and smooth curve fitting techniques. Enhanced LE8 scores were linked to improved BMD at the femoral neck. Notably, a 10-point increment in the LE8 score was associated with a rise in BMD by 0.04 g/cm² [β = 0.04, 95% CI: 0.03-0.05]. The data indicate a strong positive association between cardiovascular health, as measured by LE8, and BMD. These results support the development of holistic health strategies that promote cardiovascular health to potentially improve bone density.

Sleep Disruption and Bone Health

PURPOSE OF REVIEW

Review recent literature investigating the relationship between bone health and sleep/circadian disruptions (e.g., abnormal sleep duration, night shift work).

RECENT FINDINGS

Short and long sleep are associated with low bone mineral density (BMD). Recent data from observational studies identified an increased risk of fracture in women with short sleep. Studies suggest that age, sex, weight change, and concurrent circadian misalignment may modify the effects of sleep restriction on bone metabolism. Interventional studies demonstrate alterations in bone metabolism and structure in response to circadian disruption that could underlie the increased fracture risk seen with night shift work. The effects of sleep and circadian disruption during adolescence may have lifelong skeletal consequences if they adversely impact bone modeling. Data suggest that short sleep and night shift work negatively impact bone metabolism and health. Rigorous studies of prevalent sleep and circadian disruptions are needed to determine mechanisms and develop prevention strategies to optimize lifelong skeletal health.

Night shift work and osteoporosis - bone turnover markers among female blue-collar workers in Poland

Osteoporosis is an important public health problem worldwide. Although many factors relating to bone structure have been described so far, the current knowledge on the occupational factors that may affect bone tissue metabolism is strongly limited. Literature data suggest that night shift work, via circadian rhythm disruption, may be considered a potential risk factor. To this date, only five epidemiological studies addressing this problem have been conducted worldwide. The outcomes of three studies confirmed such relationship, namely, a higher fracture risk was found among nurses with a long lifetime duration of night shift work in one study; and a lower bone mineral density was associated with occupational activity during night-time in two studies. In adults, the bone undergoes constant remodelling through bone resorption followed by bone formation. The various molecules released into the circulatory system during these processes are called bone turnover markers. We investigated the possible associations between night shift work and selected bone turnover markers: N-terminal propeptide of type I procollagen (P1NP), C-terminal cross-linked telopeptide of type I collagen (CTX), osteocalcin, osteopontin, fibroblast growth factor 23 (FGF-23) and osteoprotegerin, measured in plasma of 189 female blue-collar workers. A significantly higher bone turnover rate was noted among the women working night shifts than among those working only during the day. This may potentially lead to a future development of osteoporosis in this population even if the macroscopic changes in the bone structure are not detectable. Night shift work is a prevailing occupational characteristics nowadays. It has been estimated that about 15-20% of the working population in Europe and the USA perform work under this system. Thus, the problem of osteoporosis can affect a large part of the working-age population.