Relationship Between Obesity and Risk of Major Osteoporotic Fracture in Postmenopausal Women: Taking Frailty Into Consideration

The Causal Relationship between PCSK9 Inhibitors and Osteoporosis Based on Drug-Targeted Mendelian Combined Mediation Analysis

PCSK9 inhibitors have been shown to lower serum low density lipoprotein cholesterol (LDL-C) levels and are considered integral in the treatment of cardiovascular diseases. However, the potential association between PCSK9 inhibitors and osteoporosis is unclear now. In this study, drug-targeted mendelian randomization (MR) was utilized in conjunction with mediation analysis including bone mineral density (BMD), total 25-hydroxyvitamin D (T25(OH)D) levels and calcium supplementation to investigate the causal relationship between PCSK9 inhibitors and osteoporosis. The LDL-C level was chosen as the exposure variable in a sample size of 173,082 individuals. We conducted a MR analysis on the relationship between PCSK9 inhibitors and osteoporosis, elucidating the mediators involved. Utilizing the inverse variance weighted (IVW) method, we found the risk of osteoporosis was reduced by 0.6% in those who used PCSK9 inhibitors compared with non-users (OR: 0.994, 95%CI: 0.991-0.998, P < 0.001). In people aged 30-45 years, the risk of low BMD was 1.176 times higher among PCSK9 inhibitor users compared to non-users (OR: 1.176, 95%CI: 1.017-1.336, P = 0.045). Conversely, people aged 45-60 years who used PCSK9 inhibitors had a 14.9% lower risk of low BMD compared to non-users (OR: 0.851, 95%CI: 0.732-0.968, P = 0.007). Mediation analysis revealed that 43.33% of the impact of PCSK9 inhibitors on osteoporosis was mediated through BMD levels, with the remaining 56.67% being a direct effect. Effects of PCSK9 inhibitors on BMD levels varied in different ages. In addition, the risk of high serum T25(OH)D levels were 1.091 times among PCSK9 inhibitor users compared to non-users (OR: 1.091, 95%CI: 1.065-1.112, P < 0.001), providing valuable insights for clinicians.

Bone mineral density T-scores comparison between obese and non-obese individuals included in a Fracture Liaison Service following a recent fragility fracture

We used data from a Fracture Liaison Service to compare the mean T-scores of obese and non-obese patients after a recent fragility fracture. After adjusting for age, sex, and diabetes mellitus, T-score values were significantly higher at all measurement sites in obese patients, with a mean difference of 1 SD.

PURPOSE

This study aimed to compare the mean T-scores of obese and non-obese patients after recent fragility fractures.

METHODS

Over a period of 5 and a half years, from January 2016 to May 2021, patients from a fracture liaison service were identified and their demographic characteristics, osteoporosis risk factors, BMD T-scores, and fracture sites were compared between obese (BMI ≥ 30 kg/m2) and non-obese (19 kg/m2 < BMI < 30 kg/m2) patients.

RESULTS

A total of 712 patients were included (80.1% women; mean age 73.8 ± 11.3 years). Sixteen % had type 2 diabetes mellitus and 80% had a major osteoporotic fracture (MOF). 135 patients were obese and 577 non-obese, with obese patients younger (p < 0.001) and more frequently female (p = 0.03). Obese patients presented with fewer hip fractures (10% vs. 21%, p = 0.003) and more proximal humerus fractures (16% vs. 7%, p < 0.001) than non-obese patients. After adjusting for age, sex, and diabetes mellitus, BMD T-score values were significantly higher at all measurement sites (lumbar spine, total hip, and femoral neck) in obese patients than in non-obese patients for all types of fractures, with a mean difference of 1 standard deviation (p < 0.001 for all comparisons). The same results were observed in the population limited to MOF.

CONCLUSIONS

Given the crucial role of BMD T-score in determining the need for anti-osteoporotic medication following fragility fractures, it is reasonable to question the existing T-score thresholds in obese patients.

Obesity and risk of fracture in postmenopausal women: a meta-analysis of cohort studies

BACKGROUND

Obesity is associated with an increased risk of fracture in adults, but is unclear in postmenopausal women. We aim to determine the association of obesity with the risk of fracture in postmenopausal women.

METHODS

PubMed, EMBASE, Cochrane Library and Web of Science were searched up to 11 April 2022 for cohort studies. And the included studies regarding the relationship between obesity with all cause of fracture in postmenopausal women were included in our meta-analysis. Data were screened and extracted independently by two reviewers. The relative risks (RR) were estimated using a random-effects model. Between-study heterogeneity was assessed using Cochran's Q and I² statistics.

RESULTS

Eight cohort studies comprising 671,532 postmenopausal women and 40,172 fractures were included. Overall, the pooling analysis shows that obesity in postmenopausal women is associated with an increased risk of all-cause fracture (relative ratio (RR) = 1.18; 95% confidence interval (CI):1.09-1.28, I² = 86.3%, p = .000). Sub-analyses for each site of fracture indicate that obesity was associated with an increased risk of vertebral fracture in postmenopausal women (RR = 1.154, 95% CI: 1.020-1.305, I² = 94.5%, p = .023), but reduced the risk of pelvic fracture (RR = 0.575, 95% CI:0.470-0.702, I² = 0.0%, p = .000). There is no statistically significant difference in the risk of hip and humerus fractures associated with obesity in postmenopausal women.

CONCLUSION

Obesity is associated with an increased risk of all-cause and vertebral fractures in postmenopausal women, but is a protective factor for pelvic fractures. Our findings suggest that postmenopausal women who regulate their weight might lower their risk of fractures.Registration: (PROSPERO: CRD42022324973)KEY MESSAGESObesity is associated with an increased risk of all-cause and vertebral fractures in postmenopausal women.Obesity maybe a protective factor for pelvic fractures in postmenopausal women.Postmenopausal women should regulate their weight to prevent fractures.

Influence of Obesity and Changes in Weight or BMI on Incident Fractures in Postmenopausal Women: From Peking Vertebral Fracture Study

This study aims to investigate the influence of overweight/obesity and change in weight or body mass index (BMI) on incident fractures among Chinese postmenopausal women. According to BMI, 754 postmenopausal women were categorized into normal weight (NW), overweight (OW), and obesity (OB) groups, respectively. We used data from the baseline and the second survey for statistical analysis, including anthropometric data, clinical fractures, and morphometric vertebral fractures (MVFs) assessed by X-rays. The prevalence of previous MVFs was 32.7% and 21.8% in the OB and NW groups, respectively (p < 0.05). All incident fractures and incident MVFs accounted for 10.7 and 6.3% among all participants within five years. Overweight/obesity and increase in weight or BMI during the follow-up had no associations with all incident fractures, incident MVFs, and incident clinical non-VFs among all participants. However, after multivariate adjustment, the increased BMI at baseline was the risk factor of incident MVFs in the OW group (odds ratio, OR 2.06, 95% confidence interval, 95% CI 1.16-3.66, p = 0.014), and increase in weight (OR 0.89, 95% CI 0.79-0.99, p = 0.036) or BMI (OR 0.77, 95% CI 0.59-0.99, p = 0.045) during the follow-up were the protective factors of all incident fractures in the NW group. Overweight/obesity and change in weight or BMI do not correlate with fracture risk in postmenopausal women, but an increase in weight is the protective factor against incident fractures in normal-weight participants. Overweight postmenopausal women with a higher BMI should pay attention to the risk of MVFs.

Osteoporosis in adults in clinical practice (1): diagnosis and differential diagnosis

Osteoporosis is a systemic metabolic disease of the skeleton characterized by low bone strength that results in an increased risk of fracture. Fractures are associated with serious clinical consequences, including pain, disability, loss of independence, and death, as well as high healthcare costs. Early identification and intervention with patients at high risk for fracture is needed to reduce the burden of osteoporotic fractures. The identification of a patient at high risk of fracture should be followed by evaluation for factors contributing to low bone mineral density (BMD) and/or low bone quality, falls, and fractures. Components of the osteological evaluation include an assessment of BMD by dual-energy X-ray absorptiometry, osteoporosis-directed medical history and physical exam, laboratory studies, and possibly skeletal imaging. Disorders other than osteoporosis, requiring other types of treatment, may be found. This overview summarizes the basic procedures for the diagnosis and differential diagnosis of osteoporosis, which are necessary before starting treatment.

Oxidative stress bridges the gut microbiota and the occurrence of frailty syndrome

The incidence of frailty gradually increases with age. This condition places a heavy burden on modern society, of which the aging population is increasing. Frailty is one of the most complicated clinical syndromes; thus, it is difficult to uncover its underlying mechanisms. Oxidative stress (OS) is involved in frailty in multiple ways. The association between the gut microbiota (GM) and frailty was recently reported. Herein, we propose that OS is involved in the association between the GM and the occurrence of frailty syndrome. An imbalance between oxidation and antioxidants can eventually lead to frailty, and the GM probably participates in this process through the production of reactive oxygen species. On the other hand, OS can disturb the GM. Such dysbiosis consequently induces or exacerbates tissue damage, leading to the occurrence of frailty syndrome. Finally, we discuss the possibility of improving frailty by intervening in the vicious cycle between the imbalance of OS and dysbiosis.

Dietary Acid Load Was Positively Associated with the Risk of Hip Fracture in Elderly Adults

Previous studies have shown that dietary acid load (DAL) harms bone health, but the evidence is inconsistent and insufficient. This study examined the relationships between DAL and the risk of hip fracture. This case−control study contained 1070 pairs of 1:1 age-, city-, and gender-matched incident cases and controls (mean age, 71 years) recruited in Guangdong, China. Dietary information was collected using a validated 79-item food frequency questionnaire through face-to-face interviews. DAL was estimated based on established algorithms for the potential renal acid load (PRAL) and net endogenous acid production (NEAP). Higher PRAL and NEAP were dose-dependently associated with a higher risk of hip fracture in both the conditional logistic regression model and restricted cubic spline analysis after adjusting for potential covariates. The multivariate-adjusted odds ratios and 95% CI of hip fracture for tertiles 2 and 3 (vs. 1) of DAL were 1.63 (1.18, 2.25) and 1.92 (1.36, 2.71) for PRAL and 1.81 (1.30, 2.53) and 2.55 (1.76, 3.71) for NEAP in all participants (all p-trends < 0.001), respectively. Subgroup analyses showed more pronounced associations in participants with a lower body mass index. Our findings suggested positive associations between the estimated DAL and the risk of hip fractures in the elderly Chinese population.

Risk Factors of Frailty in Patients with Distal Radius Fractures

Aim

The aim of this study was to determine risk factors for the incidence of frailty in patients with distal radius fractures (DRFs).

Methods

In total, 116 patients (mean age, 66.3 ± 7.7 years) with DRFs were recruited. The participants were categorized into two groups, “frail” and “non-frail,” according to the presence or absence of frailty, respectively. The areal bone mineral densities (aBMDs) of the total hip, femoral neck, and lumbar spine were measured using dual-energy x-ray absorptiometry. The participants’ levels of resilience, depression, anxiety, nutritional intake, oral health-related quality of life, and social support were evaluated by self-reported questionnaires. The participants’ grip strength, gait speed, number of teeth present in their oral cavities, circumference of their upper arms and calves, and serum levels of vitamin D were also assessed.

Results

The participants in the “frail” group seemed to have lower aBMDs and muscle function and mass than those in the “non-frail” group. There were significant differences in grip strength, calf circumference, gait speed, and aBMD of the total hip, femoral neck, and lumbar spine between the groups. There were also significant differences in the levels of resilience and depression between the groups. A multivariate logistic regression analyses demonstrated that levels of sarcopenia, malnutritional status, and aBMDs of the total hip and femoral neck had significant relationships with the development of frailty in patients with DRFs.

Conclusions

An interdisciplinary approach involving the management of osteoporosis, sarcopenia, oral health, social relationships, and psychological support would be required for the proper management of DRF patients in preventing frailty.

Evaluating Patients for Secondary Causes of Osteoporosis

PURPOSE OF REVIEW

This review provides suggestions for the evaluation of patients with osteoporosis in order to assure that the diagnosis is correct, to identify potentially correctable conditions contributing to skeletal fragility and fracture risk, and to assist in individualizing management decisions.

RECENT FINDINGS

Some patients who appear to have osteoporosis have another skeletal disease, such as osteomalacia, that requires further evaluation and treatment that is different than for osteoporosis. Many patients with osteoporosis have contributing factors (e.g., vitamin D deficiency, high fall risk) that should be addressed before and after starting treatment to assure that treatment is effective and safe. Evaluation includes a focused medical history, skeletal-related physical examination, assessment of falls risk, appropriate laboratory tests, and rarely transiliac double-tetracycline labeled bone biopsy. Evaluation of patients with osteoporosis before starting treatment is essential for optimizing clinical outcomes.

Association between Visceral and Bone Marrow Adipose Tissue and Bone Quality in Sedentary and Physically Active Ovariectomized Wistar Rats

Background: Obesity is considered protective for bone mass, but this view has been progressively challenged. Menopause is characterized by low bone mass and increased adiposity. Our aim was to determine how visceral and bone marrow adiposity change following ovariectomy (OVX), how they correlate with bone quality and if they are influenced by physical activity. Methods: Five-month-old Wistar rats were OVX or sham-operated and maintained in sedentary or physically active conditions for 9 months. Visceral and bone marrow adiposity as well as bone turnover, femur bone quality and biomechanical properties were assessed. Results: OVX resulted in higher weight, visceral and bone marrow adiposity. Visceral adiposity correlated inversely with femur Ct.Th (r = −0.63, p < 0.001), BV/TV (r = −0.67, p < 0.001), Tb.N (r = −0.69, p < 0.001) and positively with Tb.Sp (r = 0.58, p < 0.001). Bone marrow adiposity also correlated with bone resorption (r = 0.47, p < 0.01), bone formation rate (r = −0.63, p < 0.01), BV/TV (r = −0.85, p < 0.001), Ct.Th (r = −0.51, p < 0.0.01), and with higher empty osteocyte lacunae (r = 0.39, p < 0.05), higher percentage of osteocytes with oxidative stress (r = 0.64, p < 0.0.01) and lower femur maximal stress (r = −0.58, p < 0.001). Physical activity correlated inversely with both visceral (r = −0.74, p < 0.01) and bone marrow adiposity (r = −0.92, p < 0.001). Conclusions: OVX increases visceral and bone marrow adiposity which are associated with inferior bone quality and biomechanical properties. Physical activity could contribute to reduce adipose tissue and thereby improve bone quality.