Grip strength in men and women aged 50-79 years is associated with non-vertebral osteoporotic fracture during 15 years follow-up: The Tromsø Study 1994-1995

Hand grip strength and all-cause mortality risk in individuals with decreased bone mass: a study from NHANES database

Objective

Previous studies have demonstrated that grip strength is associated with various health outcomes, including osteoporosis. However, the impact of grip strength on long-term mortality risk among individuals with low bone mass remains unclear. This study aims to investigate the association between grip strength and the risk of all-cause mortality in the population with low bone mass.

Methods

We included 1,343 cases of decreased bone mass from the NHANES database spanning 2013 to 2014. All-cause mortality data were ascertained through linkage with national death index records up to December 31, 2015. Analysis was conducted using the Cox proportional hazards regression model, and we assessed result reliability through various model adjustments and hierarchical analyses, Schoenfeld's global and individual tests are utilized to estimate the time-varying covariance in the Cox proportional hazards regression model's hypothesis.

Results

Throughout an average follow-up period of 69.5 months, 148 deaths were documented. After adjusting for covariates, a significant association between grip strength and the risk of all-cause mortality was observed in individuals with decreased bone mass (HR = 0.9, 95% CI: 0.87-0.93, p < 0.001). Individuals with normal grip strength, compared to those with low grip strength, exhibited a 56% lower risk of all-cause mortality (HR = 0.44, 95% CI: 0.29-0.67, p < 0.001). Various models consistently demonstrated similar significant trends post-adjustment. Subgroup analysis revealed an interaction between grip strength and coronary heart disease (p < 0.05). Schoenfeld's global and individual tests confirmed the reliability of the model (p > 0.05).

Conclusion

Our findings indicate that low grip strength is associated with increased all-cause mortality risk in individuals with decreased bone mass. The inclusion of routine monitoring of grip strength in patients with osteopenia and the encouragement of maintaining or improving grip strength in this population may offer a novel approach to health management for these individuals.

Association between handgrip strength weakness and asymmetry with incident hip fracture among older Chinese adults

BACKGROUND

To evaluate the association between handgrip strength (HGS) weakness and asymmetry with incident hip fracture among older Chinese adults.

METHODS

Data was obtained from the 2011 and 2015 waves of the China Health and Retirement Longitudinal Study (CHARLS). HGS weakness was defined as maximal HGS 〈 28 kg in men and < 18 kg in women. HGS asymmetry was defined as the HGS ratio < 0.9 or 〉 1.1. Participants were categorized into normal HGS, weakness only, asymmetry only, and both weakness and asymmetry. Given the sex differences in HGS, the association between HGS weakness and asymmetry was analyzed by sex using the multivariable logistic regression models.

RESULTS

A total of 4789 participants aged ≥ 60 years old without hip fracture at baseline were included in the final analysis. Over the four-year follow-up, there were 152 (3.17 %) participants having incident hip fractures, of which 69 (2.90 %) were men and 83 (3.45 %) were women. Compared to the normal group, men with both weakness and asymmetry had a significantly higher risk of incident hip fracture in the fully adjusted model (adjusted odds ratio (OR): 2.31, 95 % confidence interval (CI):1.17-4.52). There was no significant association between HGS asymmetry and weakness with hip fracture in women.

CONCLUSIONS

Our findings indicated that among the Chinese population, men with both HGS weakness and asymmetry were associated with increased odds of hip fracture, while no significant association was observed in women.

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.

Explaining declining hip fracture rates in Norway: a population-based modelling study

Background

Although age-standardised hip fracture incidence has declined in many countries during recent decades, the number of fractures is forecast to increase as the population ages. Understanding the drivers behind this decline is essential to inform policy for targeted preventive measures. We aimed to quantify how much of this decline could be explained by temporal trends in major risk factors and osteoporosis treatment.

Methods

We developed a new modelling approach, Hip-IMPACT, based on the validated IMPACT coronary heart disease models. The model applied sex- and age stratified hip fracture numbers and prevalence of pharmacologic treatments and risk/preventive factors in 1999 and 2019, and best available evidence for independent relative risks of hip fracture associated with each treatment and risk/preventive factor.

Findings

Hip-IMPACT explained 91% (2500/2756) of the declining hip fracture rates during 1999-2019. Two-thirds of the total decline was attributed to changes in risk/preventive factors and one-fifth to osteoporosis medication. Increased prevalence of total hip replacements explained 474/2756 (17%), increased body mass index 698/2756 (25%), and increased physical activity 434/2756 (16%). Reduced smoking explained 293/2756 (11%), and reduced benzodiazepine use explained (366/2756) 13%. Increased uptake of alendronate, zoledronic acid, and denosumab explained 307/2756 (11%), 104/2756 (4%) and 161/2756 (6%), respectively. The explained decline was partially offset by increased prevalence of type 2 diabetes and users of glucocorticoids, z-drugs, and opioids.

Interpretation

Two-thirds of the decline in hip fractures from 1999 to 2019 was attributed to reductions in major risk factors and approximately one-fifth to osteoporosis medication.

Funding

The Research Council of Norway.

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.

Risk Factors Associated With Fragility Fracture Among Older Adults With Fragility Fracture: A Systematic Review

Aim: To investigate risk factors of fragility fractures among older people. Data Sources: The electronic databases employed were PubMed, Science Direct, and Google Scholar from 2016 to December 2021. Review Method: The methodological quality of the studies was assessed using the National Institutes of Health (NIH) Quality Assessment Tool for Observational Cohort and Cross-sectional study. Two independent reviewers screened total 147 articles. Results: Twelve studies were finally included in this review that consisted of 7 cross sectional, 2 longitudinal and 3 cohort studies. Six studies were of good quality and six were fair. Studies that were of good quality showed that physical performance, muscle strength, and falls due to balance impairment were associated with an increased of fragility fractures. While the results for sarcopenia status were uncertain. Conclusion: This review suggests that physical functional related factors were main contributors to the risk of fragility fracture among older people. Lack of research in this area warrants more studies to be carried out in the future.

Physical capability, physical activity, and their association with femoral bone mineral density in adults aged 40 years and older: The Tromsø study 2015-2016

Since muscles can influence bone growth and vice versa, we examined if level of physical activity and physical capability tests can predict areal bone mineral density (aBMD). Both high activity level and good test performance were associated with higher aBMD, especially in women.

INTRODUCTION

Muscle influences bone formation and vice versa. Tests of physical capability and level of physical activity reflect various muscle qualities. We assessed the associations between total hip aBMD and physical activity as well as a range of standardized physical capability tests in an adult general population.

METHODS

A total of 3 533 women and men aged 40-84 years, participating in the population-based cross-sectional Tromsø study in Norway in 2015-2016, were included. Linear regression was used to assess associations between aBMD and physical activity and the physical capability tests grip strength, Timed Up and Go (TUG), Short Physical Performance Battery (SPPB), and standing balance. Non-linear associations were examined in cubic spline models. Standardized regression coefficients were calculated to compare effect sizes across physical capability measures.

RESULTS

In fully adjusted models, higher physical activity was positively associated with total hip aBMD in both sexes compared to a sedentary lifestyle. All tests of physical capability were associated with aBMD in women, SPPB showing the strongest association although effect sizes were too small to indicate clinically significant differences (1 point increase corresponded to an aBMD increase of 0.009 g/cm², CI = 0.005 to 0.012). In men, SPPB and its subtests were associated with aBMD with chair rises showing the strongest association (1 s increase in execution time corresponded to an aBMD decrease of 0.005 g/cm², CI = 0.008 to 0.002).

CONCLUSION

Physical activity was associated with aBMD, and tests of physical capability can account for some of the aBMD variations in adults aged 40 years and older, especially in women.

Early-senescent bone marrow mesenchymal stem cells promote C2C12 cell myogenic differentiation by preventing the nuclear translocation of FOXO3

AIMS

Mouse bone marrow mesenchymal stem cells (BMSCs) are pluripotent cells with self-renewal and differentiation abilities. Since the effects of senescent BMSCs on C2C12 cells are not fully clear, the present study aimed to elucidate these effects.

MAIN METHODS

Senescence-associated β-galactosidase staining and western blotting were performed to confirm the senescence of BMSCs. Immunofluorescence and western blotting were used to assess myoblast differentiation in each group. The role of the AKT/P70 signaling pathway and forkhead box O3 (FOXO3) nuclear translocation was explored by western blotting. BMSC-derived exosomes were injected into the tibialis anterior of mice, and RT-qPCR was used to assess the role of exosomes in promoting muscle differentiation.

KEY FINDINGS

Conditioned medium (CM) from early-senescent BMSCs promoted myogenic differentiation in vitro, which was detected as enhanced expression of myosin heavy chain (MHC), myogenin (MYOG), and myogenic differentiation 1 (MyoD). The AKT signaling pathway was found to be regulated by CM, which inhibited FOXO3 nuclear translocation. RT-qPCR analysis results showed that MHC, MyoD, and MYOG mRNA expression increased in the tibialis anterior of mice after exosome injection.

SIGNIFICANCE

The present study demonstrated that early-senescent BMSCs accelerated C2C12 cell myogenic differentiation, and the transcription factor, FOXO3, was the target of senescent cells. Collectively, our results suggest that the AKT/P70 signaling pathway mediates the effect of BMSCs on neighboring cells.

Impact of Bone Fracture on Muscle Strength and Physical Performance-Narrative Review

PURPOSE OF REVIEW

Low muscle strength and poor physical performance are associated with high risk of fracture. Many studies assessed clinical and functional outcomes of fractures. Fewer studies analyzed the impact of fractures on muscle strength and physical performance.

RECENT FINDINGS

Vertebral fractures (especially multiple and severe ones) are associated with back pain, back-related disability, lower grip strength, lower strength of lower limbs, lower gait speed, and poor balance. Patients with hip fracture have slower gait and lower quadriceps strength. Non-vertebral fractures were associated with lower strength of the muscles adjacent to the fracture site (e.g., grip strength in the case of distal radius fracture, knee extensors in the case of patellar fracture) and poor physical function dependent on the muscles adjacent to the fracture site (e.g., limited range of motion of the shoulder in the case of humerus fracture, gait disturbances in the case of the ankle fracture). Individuals with a fracture experience a substantial deterioration of muscle strength and physical performance which exceeds that related to aging and is focused on the period close to the fracture occurrence. After fracture, muscle strength increased and physical performance improved. The rate of normalization depended partly on the therapeutic approach and on the rehabilitation program. A subgroup of patients, mainly the elderly, never returns to the pre-fracture level of physical performance. The permanent decline of physical function after fracture may be related to the limitation of movements due to pain, low physical activity, poor health before the fracture, and reduced efficacy of retraining after immobilization.

Handgrip strength-a risk indicator for future fractures in the general population: findings from a prospective study and meta-analysis of 19 prospective cohort studies

Evolving debate suggests that handgrip strength, a measure of muscular strength, might be associated with the risk of fractures; however, the evidence is conflicting. We aimed to assess the association of handgrip strength with the risk of fracture in the general population. Handgrip strength, measured using a dynamometer, was assessed at baseline in a population-based sample of 853 men and women aged 61-73 years in the Kuopio Ischemic Heart Disease prospective cohort. Hazard ratios (HRs) with 95% confidence intervals (CIs) were estimated for incident fractures. Incident fractures (hip, humeral, or wrist) (n = 159) occurred during a median follow-up of 16.7 years. Comparing extreme tertiles of handgrip strength, the age- and sex-adjusted hazard ratio (95% CI) for fractures was 0.80 (0.55-1.18). The association remained similar on further adjustment for other potential confounders: HR (95% CI) of 0.82 (0.55-1.21). In a meta-analysis of 19 population-based prospective cohort studies (including the current study) comprising 220,757 participants and 9199 fractures (including 1302 hip fractures), the fully adjusted relative risk (RR) (95% confidence interval, CI) for incident fractures was 0.70 (0.61-0.80) comparing the top versus bottom thirds of handgrip strength. The association remained significant after trim-and-fill correction for publication bias. The corresponding RR (95% CI) for hip fractures (9 studies) was 0.61 (0.54-0.70). Handgrip was only modestly associated with fracture risk in the primary analysis, which may be driven by the low event rate. Pooled prospective cohort evidence suggests that elevated handgrip strength is associated with reduced future fracture risk.