Muscle mass is associated with incident fracture in postmenopausal women: The OFELY study

Association between obesity and the prevalence of fractures: a population-based cross-sectional study in China

Although obesity is generally associated with increased bone mass, recent data have challenged its potential protective effect. Our study found that increased BMI showed beneficial effects on BMD in a non-linear way. However, individuals with obesity, especially women, were more likely to have vertebral fractures. There was a U-shaped relationship between BMI and the prevalent fractures.

PURPOSE

To estimate the association of obesity with the prevalence of fractures in the Mainland Chinese population.

METHODS

A total of 8251 individuals from the COPS cohort were enrolled in this cross-sectional study and grouped by BMI level. The Five-Repetition Sit-to-Stand Test (5R-STS) and the Sharpened Romberg test were used to evaluate the balance ability. Vertebral fractures (VFs) were confirmed by spine X-ray examination. Prevalent fractures were defined by a self-report questionnaire which happened in the recent 5 years. The restricted cubic spline (RCS) was used to explore the non-linear relationship. Multiple linear regression and multivariable logistic regression were conducted to adjust the covariates.

RESULTS

Obesity was correlated with a reduced bone turnover rate and increased BMD. Nevertheless, there were significant non-linear correlations between BMI and BMD, with a rapid increase and plateau at extremely high BMI levels (p for non-linear < 0.001 for all). Individuals with obesity were associated with a longer time of the 5R-STS and more likely to have a positive Sharpened Romberg test, especially in women. Compared with the normal weight group, the likelihood of prevalence of VFs and the prevalent fractures were significantly increased in the obesity group, independent of the Sharpened Romberg test and lumbar spine BMD (VFs: OR = 1.88 [95% CI 1.38-2.56]; prevalent fractures: OR = 2.18 [95% CI 1.39-3.41]). Per standard deviations (SD) increase in BMI was associated with 21% and 22% increase in the prevalence of VFs and prevalent fractures, respectively. Moreover, the prevalence of prevalent fractures also elevated in the low-weight individuals (OR = 2.62 [95% CI 1.34-4.75]), which indicated a U-shaped relationship between BMI and the prevalence of prevalent fractures.

CONCLUSION

Obesity was associated with higher BMD in a non-linear manner. However, BMI was positively associated with the prevalence of VFs, and there was a U-shaped relationship between BMI and the prevalent fractures.

The path less traveled: Using structural equation modeling to investigate factors influencing bone functional morphology

OBJECTIVES

The relationship between an organism's mechanical environment and its bone strength has been long established by experimental research. Multiple intrinsic and extrinsic factors, including body mass, muscle strength, genetic background, and nutritional and/or hormonal status, are likely to influence bone deposition and resorption throughout the lifespan, complicating this relationship. Structural equation modeling (SEM) is uniquely positioned to parse this complex set of influences.

MATERIALS AND METHODS

Data from the Third National Health and Nutrition Examination Survey, including sex, total body mass, lean body mass, exercise frequency, peak body mass, and age, were analyzed using SEM to determine how they affect bone strength both individually and combined.

RESULTS

Body mass is typically the driver of cross-sectional area, but body mass and lean mass have similar effects on the polar moment of area (J). Peak body mass had a strong direct effect on J, despite decreasing strongly with increases in lean mass. Exercise also did not confer a large direct effect on cross-sectional area or J but did modify body mass and lean mass. In females, intentional weight loss was associated with decreased exercise levels.

DISCUSSION

SEM is a useful tool for parsing complex systems in bone functional morphology and has the potential to uncover causal links in the study of skeletal remodeling, including factors like weight loss or exercise that may have secondary effects.

Associations of abdominal obesity with different types of bone fractures in adults: A systematic review and dose-response meta-analysis of prospective cohort studies

Findings on the association between abdominal obesity and hip fracture were summarized in a meta-analysis in 2017; however, no study has examined the dose-response association between abdominal fat indices and hip fracture. Also, we found no meta-analysis investigating other types of bone fractures including any vertebral fractures in relation to abdominal obesity. Therefore, the present systematic review and dose-response meta-analysis of prospective cohort studies were conducted to examine the association between abdominal obesity and different types of bone fractures. A comprehensive literature search was done by searching PubMed, Scopus, Web of Science, and Google Scholar until October 2021. In total, 23 articles from prospective cohort studies with a total sample size of 3,456,631 participants were included. During the follow-up periods ranging between 4 and 26 years, 137,989 cases of bone fracture were recorded. After comparing the highest and lowest categories of abdominal fat indices, the summary relative risks (RRs) of any, hip, and vertebral fractures were 0.99 (95% CI: 0.81-1.20), 1.09 (95% CI: 0.82-1.43), and 1.18 (95% CI: 1.05-1.33), respectively, indicating a significant positive association between abdominal obesity and risk of vertebral fracture. In the non-linear dose-response analysis, abdominal obesity based on the waist-to-hip ratio (WHR) was positively associated with an increased risk of hip fracture from 0.7 to 1.1 units of WHR. In the linear analysis, a 10 cm increase in waist circumference (WC) was associated with a 3% higher risk of vertebral fracture. We found no other dose-response association for other types of bone fractures. In conclusion, abdominal obesity may be associated with a higher risk of hip and vertebral fractures.

Association of serum osteocalcin with bone microarchitecture and muscle mass in Beijing community-dwelling postmenopausal women

BACKGROUND

Osteoporosis is a systemic skeletal disease with increasing bone fragility and prone to fracture. Osteocalcin (OC), as the most abundant non collagen in bone matrix, has been extensively used in clinic as a biochemical marker of osteogenesis. Two forms of OC were stated on circulation, including carboxylated osteocalcin (cOC) and undercarboxylated osteocalcin (ucOC). OC was not only involved in bone mineralization, but also in the regulation of muscle function.

OBJECTIVE

This study explored the relationship between serum OC, cOC, ucOC levels and bone mineral density (BMD), bone microarchitecture, muscle mass and physical activity in Chinese postmenopausal women.

METHOD

216 community-dwelling postmenopausal women were randomized enrolled. All subjects completed biochemical measurements, including serum β-isomer of C-terminal telopeptides of type I collagen (β-CTX), N-terminal propeptide of type 1 procollagen (P1NP), alkaline phosphatase (ALP), OC, cOC and ucOC. They completed X-ray absorptiometry (DXA) scan to measure BMD, appendicular lean mass (ALM) and trabecular bone score (TBS). They completed high resolution peripheral quantitative CT (HR-pQCT) to assess peripheral bone microarchitectures.

RESULTS

Serum OC, cOC and ucOC were elevated in osteoporosis postmenopausal women. In bone geometry, serum ucOC was positively related with total bone area (Tt.Ar) and trabecular area(Tb.Ar). In bone volumetric density, serum OC and ucOC were negatively associated with total volume bone mineral density (Tt.vBMD) and trabecular volume bone mineral density (Tb.vBMD). In bone microarchitecture, serum OC and ucOC were negatively correlative with Tb.N and Tb.BV/TV, and were positively correlated with Tb.Sp. Serum OC and ucOC were positively associated with Tb.1/N.SD. Serum OC was negatively related with Tb.Th. Serum ucOC was positively associated with ALM. The high level of serum OC was the risk factor of osteoporosis. ALM was the protective factor for osteoporosis.

CONCLUSION

All forms of serum OC were negatively associated with BMD. Serum OC and ucOC mainly influenced microstructure of trabecular bone in peripheral skeletons. Serum ucOC participated in modulating both bone microstructure and muscle mass.

Muscle parameters in fragility fracture risk prediction in older adults: A scoping review

Half of osteoporotic fractures occur in patients with normal/osteopenic bone density or at intermediate or low estimated risk. Muscle measures have been shown to contribute to fracture risk independently of bone mineral density. The objectives were to review the measurements of muscle health (muscle mass/quantity/quality, strength and function) and their association with incident fragility fractures and to summarize their use in clinical practice. This scoping review follows the PRISMA-ScR guidelines for reporting. Our search strategy covered the three overreaching concepts of 'fragility fractures', 'muscle health assessment' and 'risk'. We retrieved 14 745 references from Medline Ovid SP, EMBASE, Web of Science Core Collection and Google Scholar. We included original and prospective studies on community-dwelling adults aged over 50 years that analysed an association between at least one muscle parameter and incident fragility fractures. We systematically extracted 17 items from each study, including methodology, general characteristics and results. Data were summarized in tables and graphically presented in adjusted forest plots. Sixty-seven articles fulfilled the inclusion criteria. In total, we studied 60 muscle parameters or indexes and 322 fracture risk ratios over 2.8 million person-years (MPY). The median (interquartile range) sample size was 1642 (921-5756), age 69.2 (63.5-73.6) years, follow-up 10.0 (4.4-12.0) years and number of incident fragility fractures 166 (88-277). A lower muscle mass was positively/not/negatively associated with incident fragility fracture in 28 (2.0), 64 (2.5) and 10 (0.2 MPY) analyses. A lower muscle strength was positively/not/negatively associated with fractures in 53 (1.3), 57 (1.7 MPY) and 0 analyses. A lower muscle function was positively/not/negatively associated in 63 (1.9), 45 (1.0 MPY) and 0 analyses. An in-depth analysis shows how each single muscle parameter was associated with each fragility fractures subtype. This review summarizes markers of muscle health and their association with fragility fractures. Measures of muscle strength and function appeared to perform better for fracture risk prediction. Of these, hand grip strength and gait speed are likely to be the most practical measures for inclusion in clinical practice, as in the evaluation of sarcopenia or in further fracture risk assessment scores. Measures of muscle mass did not appear to predict fragility fractures and might benefit from further research, on D3-creatine dilution test, lean mass indexes and artificial intelligence methods.

Muscle strength and physical performance contribute to and improve fracture risk prediction in older people: A narrative review

Osteoporotic fractures present a major health problem with an increasing prevalence in older people. Fractures are associated with premature mortality, reduced quality of life, subsequent fracture, and increased costs. Hence, it is crucial to identify those at higher risk of fracture. Fracture risk assessment tools incorporated clinical risk factors to improve fracture predictive power over BMD alone. However, fracture risk prediction using these algorithms remains suboptimal, warranting further improvement. Muscle strength and physical performance measurements have been associated with fracture risk. In contrast, the contribution of sarcopenia, the composite condition of low muscle mass, muscle strength and/or physical performance, to fracture risk is unclear. It is uncertain whether this is due to the problematic definition of sarcopenia per se or limitations of the diagnostic tools and cut-off points of the muscle mass component. The recent position statement from the Sarcopenia Definition and Outcomes Consortium confirmed the inclusion of muscle strength and performance in the definition of sarcopenia but not DXA-assessed lean mass. Therefore, clinicians should focus on functional assessment (muscle strength and performance) rather than muscle mass, at least as assessed by DXA, as predictors of fractures. Muscle strength and performance are modifiable risk factors. Resistance exercise improves muscle parameters in the elderly, potentially leading to reduced risk of falls and fractures in the general population and in those who sustained a fracture. Therapists may consider exercise intervention to improve muscle parameters and potentially reduce the risk of fractures. The aim of this review was to explore 1) the contribution of muscle parameters (i.e., muscle mass, strength, and physical performance) to fracture risk in older adults, and 2) the added predictive accuracy of these parameters beyond the existing fracture assessment tools. These topics provide the rationale for investigating strength and physical performance interventions to reduce fracture risk. Most of the included publications showed that muscle mass is not a good predictor of fracture risk, while poor muscle strength and performance are associated with an increased risk of fracture, particularly in men, independent of age, BMD, and other risk factors for fractures. Muscle strength and performance can potentially improve the predictive accuracy in men beyond that obtained by the fracture risk assessment tools, Garvan FRC and FRAX.

Menopause-Related Changes in Body Composition Are Associated With Subsequent Bone Mineral Density and Fractures: Study of Women's Health Across the Nation

During the menopause transition (MT), lean mass decreases and fat mass increases. We examined the associations of these body composition changes during the MT (2 years before to 2 years after the final menstrual period) with bone mineral density (BMD) at the end of the MT and fracture after the MT. We included 539 participants from the Study of Women's Health Across the Nation who were not taking bone-beneficial or bone-detrimental medications before or during the MT. Using multivariable linear regression, we assessed the independent associations of % lean mass loss and % fat mass gain during the MT (mutually adjusted) with femoral neck (FN) and lumbar spine (LS) BMD at the end of the MT, adjusted for pre-MT BMD, pre-MT lean and fat mass, race/ethnicity, Study of Women's Health Across the Nation (SWAN) study site, age, and cigarette use. We used Cox proportional hazards regression to quantify the relations of % lean loss and % fat gain during the MT with fracture after the MT. The Cox model was adjusted for the covariates above plus post-MT use of bone-detrimental medications, and censored at the first use of bone-beneficial medications; we further controlled for FN or LS BMD at the end of the MT. Adjusted for covariates, each standard deviation (SD) (6.9%) increment in lean mass loss was associated with 0.010 g/cm2 lower FN BMD (p < 0.0001); each SD (19.9%) increment in fat mass gain was related to 0.026 g/cm2 greater FN (p = 0.009) and LS (p = 0.03) BMD. Each SD increment in lean mass loss and fat mass gain was associated with 63% (p = 0.001) and 28% (p = 0.05) greater fracture hazard after the MT; associations were essentially unchanged by BMD adjustment. MT-related lean mass loss and fat mass gain were associated differentially with BMD; both were independently related to more fractures. Mitigating MT-related body composition changes may reduce fracture risk. © 2022 The Authors. Journal of Bone and Mineral Research published by Wiley Periodicals LLC on behalf of American Society for Bone and Mineral Research (ASBMR).

Deciphering the "obesity paradox" in the elderly: A systematic review and meta-analysis of sarcopenic obesity

Aging and obesity are two global concerns in public health. Sarcopenic obesity (SO), defined as the combination of age-related sarcopenia and obesity, has become a pressing issue. This systematic review and meta-analysis summarize the current clinical evidence relevant to SO. PubMed, Embase, and Web of Science were searched, and 106 clinical studies with 167,151 elderlies were included. The estimated prevalence of SO was 9% in both men and women. Obesity was associated with 34% reduced risk of sarcopenia (odds ratio [OR] 0.66, 95% CI 0.48-0.91; p < 0.001). The pooled hazard ratio (HR) of all-cause mortality was 1.51 (95% CI 1.14-2.02; p < 0.001) for people with SO compared with healthy individuals. SO was associated with increased risk of cardiovascular disease and related mortality, metabolic disorders, cognitive impairment, arthritis, functional limitation, and lung diseases (all ORs > 1.0, p < 0.05). The attenuated risk of sarcopenia in elderlies with obesity ("obesity paradox") was dependent on higher muscle mass and strength. Apart from unifying the diagnosis of SO, more research is needed to subphenotype people with obesity and sarcopenia for individualized treatment. Meanwhile, the maintenance of proper body composition of muscle and fat may delay or attenuate the adverse outcomes of aging.

Muscle Strength and Physical Performance Are Associated With Risk of Postfracture Mortality But Not Subsequent Fracture in Men

Muscle strength and physical performance are associated with incident fractures and mortality. However, their role in the risk of subsequent fracture and postfracture mortality is not clear. We assessed the association between muscle strength (grip strength) and performance (gait speed and chair stands time) and the risk of subsequent fracture and mortality in 830 men with low-trauma index fracture, who participated in the Osteoporotic Fractures in Men (MrOS) USA Study and had their index measurements assessed within 5 years prior to the index fracture. The annual decline in muscle strength and performance following index fracture, estimated using linear mixed-effects regression, was also examined in relation to mortality. The associations were assessed using Cox proportional hazards models adjusted for age, femoral neck bone mineral density (FN BMD), prior fractures, falls, body mass index (BMI), index fracture site, lifestyle factors, and comorbidities. Over a median follow-up of 3.7 (interquartile range [IQR], 1.3-8.1) years from index fracture to subsequent fracture, 201 (24%) men had a subsequent fracture and over 5.1 (IQR, 1.8-9.6) years to death, and 536 (65%) men died. Index measurements were not associated with subsequent fracture (hazard ratios [HRs] ranging from 0.97 to 1.07). However, they were associated with postfracture mortality. HR (95% confidence interval [CI]) per 1 standard deviation (1-SD) decrement in grip strength: HR 1.12 (95% CI, 1.01-1.25) and gait speed: HR 1.14 (95% CI, 1.02-1.27), and 1-SD increment in chair stands time: HR 1.08 (95% CI, 0.97-1.21). Greater annual declines in these measurements were associated with higher mortality risk, independent of the index values and other covariates. HR (95% CI) per 1-SD annual decrement in change in grip strength: HR 1.15 (95% CI, 1.01-1.33) and in gait speed: HR 1.38 (95% CI, 1.13-1.68), and 1-SD annual increment in chair stands time: HR 1.28 (95% CI, 1.07-1.54). Men who were unable to complete one or multiple tests had greater risk of postfracture mortality (24%-109%) compared to those performed all tests. It remains to be seen whether improvement in these modifiable factors can reduce postfracture mortality. © 2022 The Authors. Journal of Bone and Mineral Research published by Wiley Periodicals LLC on behalf of American Society for Bone and Mineral Research (ASBMR).

Prior loss of body mass index, low body mass index, and central obesity independently contribute to higher rates of fractures in elderly women and men

We aimed to comprehensively evaluate the association of body composition with fracture risk using longitudinal data from a Swedish cohort of 44,366 women and men (mean age of 70 years) and a subcohort of 5022 women. We estimated hazard ratios (HRs) of fracture for baseline body mass index (BMI), BMI change during the prior 12 and 18 years, baseline waist-to-height ratio, total and regional distribution of fat and lean mass, with and without areal bone mineral density (BMD) adjustment. During follow-up (median 8.7 years), 7290 individuals sustained a fracture, including 4279 fragility fractures, of which 1813 were hip fractures. Higher baseline BMI and prior gain in BMI were inversely associated with all types of fracture. Lower fracture rate with higher baseline BMI was seen within every category of prior BMI change, whereas higher prior BMI gain conferred a lower rate of fracture within those with normal baseline BMI. Each standard deviation (SD) higher baseline waist-to-height ratio, after adjustment for BMI, was associated with higher rates of hip fracture in both women and men (HR 1.12; 95% CI, 1.05-1.19). In the subcohort (median follow-up 10 years), higher baseline fat mass index (FMI) and appendicular lean mass index (LMI) showed fracture-protective effects. After BMD adjustment, higher baseline BMI, total LMI, FMI, and higher prior BMI gain were associated with higher fracture rate. Baseline fat distribution also was associated with fracture rate; a 1-SD higher android to gynoid fat mass ratio in prior BMI gainers was associated with BMD-adjusted HRs of 1.16 (95% CI, 1.05-1.28) for any fracture and 1.48 (95% CI, 1.16-1.89) for hip fracture. This pattern was not observed among prior BMI losers. These findings indicate that for optimal fracture prevention, low baseline BMI, prior BMI loss and high baseline central obesity should be avoided in both women and men. © 2021 The Authors. Journal of Bone and Mineral Research published by Wiley Periodicals LLC on behalf of American Society for Bone and Mineral Research (ASBMR).

Effects of recreational team handball on bone health, postural balance and body composition in inactive postmenopausal women - A randomised controlled trial

This study reports the effects of a recreational team handball exercise programme (randomised controlled trial, RCT) on bone health, postural balance and body composition in inactive postmenopausal women without previous experience of the sport. Sixty-seven postmenopausal women (68.3 ± 6.2 years, stature 156.9 ± 5.8 cm, body mass 65.6 ± 9.6 kg, body fat 40.9 ± 5.9%, VO_2peak 25.2 ± 3.6 mL·min^-1·kg^-1) were randomised into team handball (THG, n = 41) and control (CG, n = 26) groups. During the 16-week intervention period, THG performed two to three 60-min training sessions per week, while CG continued with their habitual physical activity. Bone mineral density (BMD) and content (BMC), biochemical bone formation (osteocalcin (OC), procollagen type-1 amino-terminal propeptide (P1NP)) and resorption (carboxy-terminal type-1 collagen crosslinks (CTX)) markers, postural balance, body fat and lean mass were evaluated at baseline and post intervention. A time x group interaction (p ≤ 0.02) was shown for lumbar spine BMD (+1.5%) and BMC (+2.3%), P1NP (+37.6 ± 42.4%), OC (+41.9 ± 27.0%) and postural balance (-7 ± 37% falls), in favour of THG with no changes in CG. This RCT showed that short-term recreational team handball practice had an impact on bone turnover and was effective for improving bone health and postural balance in postmenopausal women without previous experience of the sport, hence potentially helping to reduce the risk of falls and fractures.

Impact of waist circumference on the risk of vertebral fracture: A nationwide cohort study in South Korea

Evidence on the association between abdominal obesity and vertebral fracture (VF) risk is limited. We examined the association of waist circumference (WC) and abdominal obesity with VF risk in 352,095 South Korean participants aged ≥40 years who underwent health checkups between 2009 and 2012. Abdominal obesity was defined by WC ≥90 cm in men and ≥ 85 cm in women according to the Asian-specific WC cutoff for abdominal obesity. Participants were a representative sample cohort of the Korean National Health Insurance System. The hazard ratios (HRs) and 95% CIs of VF development were determined using multivariable Cox proportional hazard regression analysis. During the 5.5 years of follow-up, there were 2030 and 4968 new cases of VF in men and women, respectively. In men, those with abdominal obesity showed an elevated HR (1.11, 95% CI: 1.01-1.23) of incident VF than did those without abdominal obesity. In women, the HRs of VF increased in higher WC groups after adjusting for confounders (P for trend <0.001); the HR decreased in those with WC <75.0 cm (HR: 0.81, 95% CI: 0.75-0.88) and increased in those with WC 85.0-89.9 cm (HR: 1.12, 95% CI: 1.02-1.22), 90.0-94.9 cm (HR: 1.19, 95% CI: 1.08-1.32), and ≥ 95.0 cm (HR: 1.27, 95% CI: 1.12-1.43) compared with those with WC 80.0-84.9 cm. This association persisted after stratification by age in women. WC and abdominal obesity were positively associated with VF risk in women, and abdominal obesity was associated with VF risk even in men. The consideration of WC and controlling abdominal obesity may be helpful in reducing future VF risk.

Relationships Between Level and Change in Sarcopenia and Other Body Composition Components and Adverse Health Outcomes: Findings from the Health, Aging, and Body Composition Study

We investigated how baseline values and rates of decline in components of sarcopenia and other body composition parameters relate to adverse clinical outcomes using the Health, Aging, and Body Composition Study. 2689 participants aged 70-79 years were studied. Appendicular lean mass, whole body fat mass, and total hip BMD were ascertained using DXA; muscle strength by grip dynamometry; and muscle function by gait speed. Baseline values and 2-3 year conditional changes (independent of baseline) in each characteristic were examined as predictors of mortality, hospital admission, low trauma fracture, and recurrent falls in the subsequent 10-14 years using Cox regression (generalized estimating equations used for recurrent falls) with adjustment for sex, ethnicity, age, and potential confounders. Lower levels and greater declines in all parameters (excluding hip BMD level) were associated (p < 0.05) with increased rates of mortality; fully-adjusted hazard ratios per SD lower gait speed and grip strength were 1.27 (95% CI 1.19, 1.36) and 1.14 (1.07, 1.21), respectively. Risk factors of hospital admission included lower levels and greater declines in gait speed and grip strength, and greater declines in hip BMD. Lower levels and greater declines in fat mass and hip BMD were associated with low trauma fracture. Lower gait speed, higher fat mass, and both lower levels and greater declines in grip strength were related to recurrent falls. Lower baseline levels and greater declines in musculoskeletal parameters were related to adverse outcomes. Interventions to maximize peak levels in earlier life and reduce rates of age-related decline may reduce the burden of disease in this age group.

General and central obesity operate differently as predictors of falls requiring medical care in older women: a population-based cohort study in Spain

OBJECTIVES

to examine the association of general and abdominal obesity with falls, falls requiring medical care and falls with fractures in older women.

DESIGN

a population-based prospective cohort of 1,185 women aged ≥60 in Spain, followed up from 2008 to 2010 through 2012.

MEASURES

weight, height and waist circumference were measured at baseline using standardised techniques. Participants were classified according to body mass index as normal weight (<25), overweight (25-29.9) and general obesity (≥30). Abdominal obesity was defined as waist circumference >88 cm. In 2012, participants reported the falls experienced in the previous year. Logistic regression models were mutually adjusted for general and abdominal obesity and for main confounders.

RESULTS

in this cohort of older women, a total of 336 women experienced falls, 168 of them had falls requiring medical care and 64 falls with fractures. For falls, no association was found with general obesity nor abdominal obesity. However, compared with normal weight, overweight women had a decreased risk for falls requiring medical care [odds ratio (OR) 0.57; 95% confidence interval (CI) 0.34-0.94] and for falls with fractures (OR 0.27; 95% CI 0.12-0.63). The corresponding values for general obesity were 0.44 (0.24-0.81) and 0.30 (0.11-0.82). Abdominal obesity was positively associated with falls requiring medical care (OR 1.82; 95% CI 1.12-2.94) and falls with fractures (OR 2.75; 95% CI 1.18-6.44).

CONCLUSIONS

in older women, general obesity may protect from falls requiring medical care and falls with fractures. On the contrary, abdominal obesity increased the risk of suffering from types of falls.

Short- and Long-Term Reciprocal Bone-Muscle Relationships in the Upper and Lower Extremity of Afro-Caribbean Men by DXA: A Longitudinal Analysis of the Tobago Bone Health Study

Little is known about the time course of muscle–bone effects and whether a reciprocal clinical effect of bone on muscle is present. We hypothesized that lean mass (LM) measures at the arms and legs have a stronger relationship with BMD measured within the same region than the reciprocal effect. The Tobago Bone Health Study was used to address this hypothesis, examining body composition data from total body DXA scans obtained at 0, 48‐, and 120‐month visits. A longitudinal analysis of LM, LM/height² (LMI), and LM/BMI was conducted at the upper and lower extremities separately, in relation to BMD within the corresponding region. A cross‐lagged panel model was used to study pathways from 0 to 120 months for muscle–bone and bone–muscle effects within the same visit, and across each lagged period. Models accounted for age, height, weight, race, arthritis, prior nontraumatic fracture after age 40, number of units of alcohol consumed per week, current smoking, diagnosis of diabetes mellitus, amount of walking in the last week, grip strength, and hospitalizations. Significant models demonstrating parsimony, and meeting absolute and relative fit criteria were retained. Among 1286 Afro‐Caribbean men (mean age: 53 ± 9 years, BMI: 27.43 ± 4.23 kg/m²) with data available for all visits, LM, LMI, and LM/BMI had modest contemporaneous relationships with BMD, which dissipated with lagged time. The size of these effects was stronger at the legs than at the arms. These lagged effects were primarily mediated through indirect same time‐point muscle–bone relations rather than a true directly lagged effect. Bone density showed only a small effect on LM arm measures across lagged time, but this was impossible to tease‐out from same time‐point relations. These results suggest muscle–bone relationships are not long‐lasting at least beyond 48 months. Efforts to maintain muscle and bone strength should focus on shorter‐term interventions. More studies are needed with serial bone–muscle imaging over shorter periods. © 2020 The Authors. JBMR Plus published by Wiley Periodicals LLC on behalf of American Society for Bone and Mineral Research.

Decline in Muscle Strength and Performance Predicts Fracture Risk in Elderly Women and Men

CONTEXT

Muscle strength and performance are associated with fractures. However, the contribution of their rate of decline is unclear.

OBJECTIVE

To assess the independent contribution of the rate of decline in muscle strength and performance to fracture risk.

DESIGN, SETTING, AND PARTICIPANTS

Community-dwelling women (n = 811) and men (n = 440) aged 60 years or older from the prospective Dubbo Osteoporosis Epidemiology Study followed from 2000 to 2018 for incident fracture. Clinical data, appendicular lean mass/height2 (ht)2, bone mineral density, quadricep strength/ht (QS), timed get-up-and-go (TGUG), 5 times repeated sit-to-stand (5xSTS), and gait speed (GS) measured biennially. Rates of decline in muscle parameters were calculated using ordinary least squares regression and fracture risk was assessed using Cox's models.

MAIN OUTCOME

Incident low-trauma fracture ascertained by x-ray report.

RESULTS

Apart from lean mass in women, all muscle parameters declined over time. Greater rates of decline in physical performance were associated with increased fracture risk in women (Hazard ratios [HRs] ranging from 2.1 (95% CI: 1.5-2.9) for GS to 2.7 (95% CI: 1.9-3.6) for 5xSTS, while in men only the decline in GS was associated with fracture risk (HR: 3.4 [95% CI: 1.8-6.3]). Baseline performance and strength were also associated with increased fracture risk in men (HRs ranging from 1.8 (95% CI: 1.1-3.0) for QS to 2.5 (95% CI: 1.5-4.1) for TGUG, but not in women.

CONCLUSION

Rate of decline in physical performance in both genders, and baseline strength and performance in men, contributed independently to fracture risk. Sit-to-stand and GS were the tests most consistently associated with fractures. Further studies are required to determine whether muscle strength and/or performance improve the predictive accuracy of fracture prediction models.

Where Two Common Conditions of Aging Meet: Osteoarthritis and Sarcopenia

Osteoarthritis and sarcopenia are the most frequently described musculoskeletal disorders in older persons but the intertwining of these conditions and of their functional and cellular causes is complex. This narrative review aims to identify the links between osteoarthritis and sarcopenia described 1-in clinical studies, 2-in in vitro studies, and 3-the available treatment strategies for both conditions. Electronic databases were used for the literature search of all studies investigating the relationship between sarcopenia and the presence of concomitant osteoarthritis. This review identified a limited number of clinical and morphometric studies on the complex relationship between osteoarthritis and sarcopenia. Studies present a number of methodological limitations due to definition and assessment of both entities. Low lean mass is one of the main actors of this cross-talk between muscle and bone, and adipose tissue plays a major role that had been underestimated. Bone Morphogenetic Proteins and myostatin pathways are key mediators and play an important role in both muscle and bone homeostasis. Common therapeutic recommendations are still missing. There is a need for good quality prospective studies on concomitant sarcopenia and osteoarthritis, more translational research, and pharmacological and non-pharmacological therapies in order to identify common denominators for the management of sarcopenia, osteoarthritis, and their comorbidities.

Association between abdominal obesity and fragility fractures among elderly Israeli women

BACKGROUND

Obesity has been traditionally viewed as a protective factor for fractures. Recent studies have challenged this concept, particularly regarding abdominal obesity. We aimed to investigate the association between abdominal obesity, body mass index (BMI) and fragility fractures prevalence in a sample of community-dwelling elderly Israeli women.

METHODS

The data in this cross-sectional study were based on 'Mabat Zahav'-a survey of a nationally representative sample of elderly Israelis. The study population included 669 women. Data on fragility fractures site and circumstances were self-reported, and height, weight, waist and calf circumferences were measured. Waist circumference (WC) variable was divided into tertiles: < 88 cm, 88-99 cm and > 99 cm.

RESULTS

Sixty-five women reported fragility fractures (14 hip fractures, 18 vertebral fractures and 39 wrist fractures). Mean age was 73.9 ± 5.9 years, mean BMI was 29.9 ± 5 kg/m² and mean WC was 93.9 ± 12 cm. While BMI was not associated with osteoporotic fractures, abdominal obesity (WC > 88 cm) was positively associated with fragility fractures, independently of age, smoking, physical activity [middle and high WC tertiles {3.15 (95% CI 1.41-7.02), 2.78 (95% CI 1.05-7.31), respectively}].

CONCLUSIONS

Among this sample of elderly women, abdominal obesity was positively associated with fragility fractures, independently of age, smoking, physical activity and BMI. Waist circumference, an easily measured anthropometric indicator, may be useful for assessing the risk of fragility fractures in elderly women, particularly among those with normal or high BMI-a vast population which has been traditionally considered as having lower fracture risk.

Loss in DXA-estimated total body lean mass but not fat mass predicts incident major osteoporotic fracture and hip fracture independently from FRAX: a registry-based cohort study

During median follow-up 6.0 years in 9622 individuals, prior loss in estimated total body lean mass (TBLM), but not total body fat mass loss (TBFM), was associated with increased fracture risk, particularly for hip fracture.

INTRODUCTION

Weight loss, and especially muscle loss, adversely affects skeletal health. The FRAX® tool considers baseline body mass index, but not body composition nor changes in its components over time. Our aim was to compare the independent associations between prior loss in DXA-estimated TBLM and TBFM and subsequent fracture risk.

METHODS

We identified women and men age 40 years or older with two DXA assessments at least 1 year apart (median interval 3.3 years). TBLM and TBFM were estimated from weight, sex, and DXA of the spine and hip. Incident fractures and deaths were ascertained from linked population-based health service data after the date of the second DXA. Hazard ratios (HRs) from Cox regression models were used to study time to fracture from prior loss in TBLM and TBFM adjusted for FRAX-related covariates.

RESULTS

The study population consisted of 9622 individuals (mean age 67 [SD 10] years, 95% female). We identified 692 subjects with incident major osteoporotic fracture [MOF] and 194 with hip fracture. Mean TBLM loss was significantly greater in those with incident MOF and hip fracture (P < 0.001) while TBFM loss was only significantly greater in those with incident hip fracture (P < 0.001). Each SD greater TBLM loss was associated with 10-13% increased MOF risk and 29-38% increased hip fracture risk, adjusted for TBFM loss and other covariates. Prior TBFM loss was not associated with fractures when adjusted for TBLM loss.

CONCLUSIONS

Prior loss in total body lean mass, but not in fat mass, is associated with increased fracture risk, particularly hip fracture, independent of other risk factors. This is consistent with the hypothesis that muscle loss (sarcopenia) adversely impacts skeletal health and fracture risk.

The Favorable Effects of a High-Intensity Resistance Training on Sarcopenia in Older Community-Dwelling Men with Osteosarcopenia: The Randomized Controlled FrOST Study

Purpose

Sarcopenia, the loss of muscle mass combined with the loss of muscle function, has become a public health issue. There is an urgent need for interventions. The study aimed to determine the effect of high-intensity resistance training (HI-RT), a time- and cost-efficient training modality, on sarcopenia in osteosarcopenic (OS) older men.

Methods

Forty-three community-dwelling men aged ≥72 years from Northern Bavaria, Germany, with OS were randomly assigned to either an active HI-RT group (HI-RT) or an inactive control group (CG). Both received dietary protein (up to 1.5 g/kg/day in HI-RT and 1.2 g/kg/day in CG) and Vitamin-D (up to 800 IE/d) supplements. The HI-RT was applied as a consistently supervised single-set training on resistance exercise machines using intensifying strategies, with two training sessions/week, structured into three phases (ranging from 8 to 12 weeks) totaling 28 weeks. The primary study endpoint was the Sarcopenia Z-score; secondary endpoints were changes in the underlying physiological parameters, skeletal muscle mass index (SMI), handgrip-strength and gait velocity.

Results

The results show a significant effect of the exercise intervention on the sarcopenia Z-score in the HI-RT (p<0.001) and a significant worsening of it in the CG (p=0.012) in the intention-to-treat analysis, as well as a significant intergroup change (p<0.001). Analysis upon the underlying parameters showed a significant increase of skeletal muscle mass index (SMI) in the HI-RT group (p<0.001) and a significant intergroup difference of SMI (p<0.001) and handgrip strength (p<0.001). There were no adverse effects related to dietary supplementation or training.

Conclusion

The results clearly confirm the favorable effects of HI-RT on sarcopenia. We conclude that HI-RT is a feasible, highly efficient and safe training modality for combating sarcopenia, also in the elderly.

Differences in the relation between bone mineral content and lean body mass according to gender and reproductive status by age ranges

The present study aims: (1) to explore the influence of lean mass (LM) on bone mineral content (BMC), (2) to investigate the pubertal influences on the BMC-LM relation, and (3) to perform Z-score charts of BMC-LM relation, stratified by gender and reproductive status categorized by age ranges. A cross-sectional analysis was conducted using 4001 healthy subjects between 7 and 90 years participating in the Health Workers Cohort Study. Of these, 720 participants were ≤ 19 years, 2417 were women ≥ 20 years, and 864 were men ≥ 20 years. Using Dual X-ray absorptiometry (DXA), we measured BMC and LM. Participants' pubertal development was assessed according to Tanner's stage scale. To describe BMC-LM relation, simple correlation coefficients were computed. To produce best-fit equations, an ANOVA test was conducted. Z-score graphs for the BMC-LM relation were obtained. In general, the BMC-LM correlations were linear and highly significant. For boys, curves were virtually parallel, with similar intercepts and a progressive displacement of values toward the upper-right region of the graph, for each Tanner subgroup. For girls, curves for Tanner 1-2 and 4-5 stages were parallel; but, in girls Tanner 4-5, the intercepts were significantly higher by about +300-400 g of BMC (P < 0.001). For postmenopausal women, the curve was parallel to that for the premenopausal but showed a lower intercept (P < 0.001). We provide DXA reference data on a well-characterized cohort of 4001 healthy subjects. These reference curves provide a reference value for the assessment and monitoring of bone health in all age groups included in the present study.

Implications of low muscle mass across the continuum of care: a narrative review

Abnormalities in body composition can occur at any body weight. Low muscle mass is a predictor of poor morbidity and mortality and occurs in several populations. This narrative review provides an overview of the importance of low muscle mass on health outcomes for patients in inpatient, outpatient and long-term care clinical settings. A one-year glimpse at publications that showcases the rapidly growing research of body composition in clinical settings is included. Low muscle mass is associated with outcomes such as higher surgical and post-operative complications, longer length of hospital stay, lower physical function, poorer quality of life and shorter survival. As such, the potential clinical benefits of preventing and reversing this condition are likely to impact patient outcomes and resource utilization/health care costs. Clinically viable tools to measure body composition are needed for routine screening and intervention. Future research studies should elucidate the effectiveness of multimodal interventions to counteract low muscle mass for optimal patient outcomes across the healthcare continuum. Key messages Low muscle mass is associated with several negative outcomes across the healthcare continuum. Techniques to identify and counteract low muscle mass in clinical settings are needed.

Defining sarcopenia in terms of skeletal health

Among several sarcopenic indices, height-adjusted appendicular lean mass (ALM) in men and BMI-adjusted ALM in women are associated with fragility fracture. Handgrip strength is the risk factor for fragility fracture.

PURPOSE

Various sarcopenia definitions and cutoff points result in mixed skeletal health results. Here, we aimed to determine a suitable definition and elucidate the cutoff values of sarcopenic indices for identifying fracture risk in a community-dwelling Korean cohort.

METHODS

In an Ansung cohort study (2009-2010), we included 1201 men aged > 50 years and 1627 postmenopausal women with a median age of 64 years. Body composition and bone mineral density were derived on dual-energy X-ray absorptiometry. Grip strength was measured using a hand dynamometer. Fragility fractures included the history of osteoporotic fractures using self-reported questionnaires.

RESULTS

Among appendicular lean mass (ALM)/body mass index (BMI), ALM/height², and ALM/weight, ALM/height² for men and ALM/BMI for women significantly predicted fragility fractures. On receiver operating characteristic curve analysis, the cutoff values of ALM/height² in men and ALM/BMI in women were 7.69 kg/m², and 0.57, respectively. The optimal grip strength values were 31 kg in men and 19 kg in women. The odds ratios of low ALM/height² (95% confidence interval) and weak grip strength for fragility fracture were 1.95 (1.03-3.68) and 2.05 (1.01-4.18), respectively, in men after covariate adjustment. The combination of low ALM/height² and weak grip strength increased fragility fractures 2.16-fold in men. Only the combination of low ALM/BMI and grip strength increased the fracture risk by 1.76-fold in women.

CONCLUSIONS

In men, low ALM/height² or grip strength played a role in fragility fractures. In women, only the combination of low ALM/BMI and grip strength had discriminatory power for fragility fractures.

The QUALYOR (QUalité Osseuse LYon Orléans) study: a new cohort for non invasive evaluation of bone quality in postmenopausal osteoporosis. Rationale and study design

The diagnostic performance of densitometry is inadequate. New techniques of non-invasive evaluation of bone quality may improve fracture risk prediction. Testing the value of these techniques is the goal of the QUALYOR cohort.

INTRODUCTION

The bone mineral density (BMD) of postmenopausal women who sustain osteoporotic fracture is generally above the World Health Organization definition for osteoporosis. Therefore, new approaches to improve the detection of women at high risk for fracture are warranted.

METHODS

We have designed and recruited a new cohort to assess the predictive value of several techniques to assess bone quality, including high-resolution peripheral quantitative computerized tomography (HRpQCT), hip QCT, calcaneus texture analysis, and biochemical markers. We have enrolled 1575 postmenopausal women, aged at least 50, with an areal BMD femoral neck or lumbar spine T-score between - 1.0 and - 3.0. Clinical risk factors for fracture have been collected along with serum and blood samples.

RESULTS

We describe the design of the QUALYOR study. Among these 1575 women, 80% were aged at least 60. The mean femoral neck T-score was - 1.6 and the mean lumbar spine T-score was -1.2. This cohort is currently being followed up.

CONCLUSIONS

QUALYOR will provide important information on the relationship between bone quality variables and fracture risk in women with moderately decreased BMD.

Low Skeletal Muscle Mass is Associated with the Risk of Low Bone Mineral Density in Urban Dwelling Premenopausal Women

To evaluate the relationship between skeletal muscle mass and bone mineral density (BMD) and to determine the association between low skeletal muscle mass and low BMD in urban dwelling young adults. This study was based on data from the 2008-2011 Korea National Health and Nutrition Examination Surveys. The subjects were 1702 20-49-year-old men and 2192 premenopausal women (age 20-55 years). BMD at the lumbar spine, femoral neck, and total hip and the appendicular skeletal muscle mass (ASM) were measured by dual-energy X-ray absorptiometry. Skeletal muscle mass index (SMI) was defined as weight-adjusted ASM. Mildly and severely low muscle skeletal mass were defined as SMI that was 1-2 and >2 standard deviations below the sex-specific mean ASM of young adults, respectively. Low BMD was defined as T score of less than -1.0 at the lumbar spine, femoral neck, and/or total hip. After adjusting for confounders, skeletal muscle mass was positively associated with BMD at the lumbar spine, femoral neck, and total hip in both men and women. Mildly and severely low skeletal muscle mass increased the risk of low BMD in premenopausal women [OR (95% CI) = 1.4 (1.1-1.9) and 2.4 (1.2-4.6), respectively] but not men. In women, low skeletal muscle mass independently was associated with the risk of low BMD at the femoral neck and total hip but not the lumbar spine. Skeletal muscle mass was independently associated with BMD in urban dwelling young men and women, but low skeletal muscle mass was associated with the risk of low BMD in premenopausal women only.

Prospective Associations of Dietary and Nutrient Patterns with Fracture Risk: A 20-Year Follow-Up Study

Studies on long-term exposure to foods/nutrients and its associations with fracture risk are scarce. Using data from the China Health and Nutrition Survey (CHNS), we determined the prospective association of dietary and nutrient patterns with fractures. Data from 15,572 adults aged ≥18 years were analyzed. Fracture occurrence was self-reported and dietary intake data were collected using a 24-h recall method for three consecutive days, for each individual across nine waves (1989–2011). We used cumulative and overall mean, recent and baseline dietary and nutrient exposures. Hazard ratios (HR) were used to determine the associations. Two dietary (traditional and modern) and two nutrient (plant- and animal-sourced) patterns were identified. After adjusting for potential confounders, study participants in the third tertiles (highest intake) of the modern dietary and animal-sourced nutrient patterns’ cumulative scores had a 34% (HR = 1.34; 95% CI: 1.06–1.71) and 37% (HR = 1.37; 95% CI: 1.08–1.72) increase in fracture risks compared to those in the first tertiles, respectively. While the overall mean factor scores of dietary and nutrient patterns had a similar (or stronger) pattern of association as the cumulative scores, no association between recent and baseline scores and fracture was found. Greater adherence to a modern dietary and/or an animal-sourced nutrient pattern is associated with a higher risk of total fractures. This suggests that a modern animal based diet is related to bone fragility. A repeated three-day 24-h recall dietary assessment provides a stronger association with fracture compared to a recent or baseline exposure.

Abdominal Obesity and Risk of Hip Fracture: A Systematic Review and Meta-Analysis of Prospective Studies

Data on the association between general obesity and hip fracture were summarized in a 2013 meta-analysis; however, to our knowledge, no study has examined the association between abdominal obesity and the risk of hip fracture. The present systematic review and meta-analysis of prospective studies was undertaken to summarize the association between abdominal obesity and the risk of hip fracture. We searched online databases for relevant publications up to February 2017, using relevant keywords. In total, 14 studies were included in the systematic review and 9 studies, with a total sample size of 295,674 individuals (129,964 men and 165,703 women), were included in the meta-analysis. Participants were apparently healthy and aged ≥40 y. We found that abdominal obesity (defined by various waist-hip ratios) was positively associated with the risk of hip fracture (combined RR: 1.24, 95% CI: 1.05, 1.46, P = 0.01). Combining 8 effect sizes from 6 studies, we noted a marginally significant positive association between abdominal obesity (defined by various waist circumferences) and the risk of hip fracture (combined RR: 1.36; 95% CI: 0.97, 1.89, P = 0.07). This association became significant in a fixed-effects model (combined effect size: 1.40, 95% CI: 1.25, 1.58, P < 0.001). Based on 5 effect sizes, we found that a 0.1-U increase in the waist-hip ratio was associated with a 16% increase in the risk of hip fracture (combined RR: 1.16, 95% CI: 1.04, 1.29, P = 0.007), whereas a 10-cm increase in waist circumference was not significantly associated with a higher risk of hip fracture (combined RR: 1.13, 95% CI: 0.94, 1.36, P = 0.19). This association became significant, however, when we applied a fixed-effects model (combined effect size: 1.21, 95% CI: 1.15, 1.27, P < 0.001). We found that abdominal obesity was associated with a higher risk of hip fracture in 295,674 individuals. Further studies are needed to test whether there are associations between abdominal obesity and fractures at other bone sites.