Bone Mineral Density of the Radius Predicts All-Cause Mortality in Patients With Type 2 Diabetes: Diabetes Heart Study

Adherence to the Mediterranean diet regulates the association between osteopenia and the risk of all-cause mortality in general population

BACKGROUND

This study aimed to explore the association of adherence to the Mediterranean diet (MD), osteopenia and the risk of all-cause mortality in general population.

METHODS

This retrospective cohort study included 5452 participants ≥ 50 years from the National Health and Nutrition Examination Survey (NHANES). The associations of osteopenia and adherence to the MD with all-cause mortality, as well as the interaction and moderating effects between the osteopenia and adherence to the MD on the all-cause mortality, were explored via univariate and multivariable Cox proportional hazards models.

RESULTS

The follow-up was from October 1, 2006, to December 31, 2019. The median survival time of patients was 81 months. In total, 4724 people were survived and 728 were dead. Osteopenia was associated with increased risk of all-cause mortality in people [hazards ratio (HR) = 1.57, 95% confidence interval (CI) 1.23-1.99]. No significant risk of all-cause mortality was found in people with high adherence to the MD compared with those with low adherence to the MD (P > 0.05). Compared to subjects with no osteopenia who had high adherence to the MD, osteopenia people who had high adherence to the MD (HR = 1.52, 95% CI 1.17-1.98) or low adherence to the MD (HR = 1.81, 95% CI 1.23-2.66) were at increased risk of all-cause mortality after adjusting for confounding factors. The relationship between osteopenia and the risk of all-cause mortality was decreased in those with high adherence to the MD (HR = 1.57, 95% CI 1.17-2.11) compared with those with low adherence to the MD (HR = 1.62, 95% CI 1.08-2.41) after adjusting for confounding factors.

CONCLUSION

The adherence to the MD regulated the association between osteopenia and the risk of all-cause mortality, which suggested the importance of adherence to the MD in those with osteopenia, and the MD could be advocated in general people.

Aging and Bone Metabolism

Changes in bone architecture and metabolism with aging increase the likelihood of osteoporosis and fracture. Age-onset osteoporosis is multifactorial, with contributory extrinsic and intrinsic factors including certain medical problems, specific prescription drugs, estrogen loss, secondary hyperparathyroidism, microenvironmental and cellular alterations in bone tissue, and mechanical unloading or immobilization. At the histological level, there are changes in trabecular and cortical bone as well as marrow cellularity, lineage switching of mesenchymal stem cells to an adipogenic fate, inadequate transduction of signals during skeletal loading, and predisposition toward senescent cell accumulation with production of a senescence-associated secretory phenotype. Cumulatively, these changes result in bone remodeling abnormalities that over time cause net bone loss typically seen in older adults. Age-related osteoporosis is a geriatric syndrome due to the multiple etiologies that converge upon the skeleton to produce the ultimate phenotypic changes that manifest as bone fragility. Bone tissue is dynamic but with tendencies toward poor osteoblastic bone formation and relative osteoclastic bone resorption with aging. Interactions with other aging physiologic systems, such as muscle, may also confer detrimental effects on the aging skeleton. Conversely, individuals who maintain their BMD experience a lower risk of fractures, disability, and mortality, suggesting that this phenotype may be a marker of successful aging. © 2023 American Physiological Society. Compr Physiol 13:4355-4386, 2023.

Clinical Characteristics and Fracture Patterns Among Postmenopausal Women with Isolated Osteoporosis at the Forearm

Patients found to have isolated osteoporosis at the 1/3 radius (1/3RO) represent a therapeutic dilemma. It is unknown whether 1/3RO is associated with an increased risk of fragility fractures, and is therefore unclear whether these patients should be treated similarly to those with osteoporosis at central sites. This retrospective study investigated the clinical significance of 1/3RO by comparing medical history, fracture prevalence, areal BMD, and Trabecular Bone Score in postmenopausal women with 1/3RO (n = 107) to age-matched women with osteoporosis at the hip and/or spine (PMO, n = 214), and to controls without osteoporosis at any site (n = 214). We then compared the clinical and densitometric characteristics among women with 1/3RO according to fracture history. The mean age of the 535 women included in the study was 71 ± 8 yr. Women with 1/3RO had BMD in the osteopenic range at all other sites (mean spine T-score = -1.0, total hip = -1.4, femoral neck = -1.7). Women with 1/3RO reported similar calcium and vitamin D intake, prevalence of primary hyperparathyroidism, chronic kidney disease, and other comorbidities compared to the other groups. The prevalence of an osteoporotic fracture of the spine, hip, wrist, or humerus tended to be higher among women with PMO compared to 1/3RO or controls (PMO: 31%, 1/3RO: 21%, Controls: 23%, p = 0.07). Among women with 1/3RO, fracture prevalence was related to older age. No other clinical characteristic distinguished women with and without fracture. Neither BMD at other sites nor TBS differed according to fracture history. Among postmenopausal women with 1/3RO, those who are older are at an increased risk of fracture, even when T-scores at other sites are well above the osteoporosis threshold. Additional research is needed to confirm our results, and to assess whether treatment should be considered to reduce fracture risk in older women with 1/3RO.

Bone Mineral Density of the 1/3 Radius Refines Osteoporosis Diagnosis, Correlates With Prevalent Fractures, and Enhances Fracture Risk Estimates

OBJECTIVE

To investigate the added value of 1/3 radius (1/3R) for the diagnosis of osteoporosis by spine and hip sites and its correlation with prevalent fractures and predicted fracture risk.

METHODS

Fracture Risk Assessment Tool (FRAX) scores for hip and major osteoporotic fractures (MOF) with/without trabecular bone score were considered proxy for fracture risk. The contribution of 1/3R to risk prediction was depicted via linear regression models with FRAX score as the dependent variable-first only with central and then with radius T-score as an additional covariate. Significance of change in the explained variance was compared by F-test.

RESULTS

The study included 1453 patients, 86% women, aged 66 ± 10 years. A total of 32% (n = 471) were osteoporotic by spine/hip and 8% (n = 115) by radius only, constituting a 24.4% increase in the number of subjects defined as osteoporotic (n = 586, 40%). Prior fracture prevalence was similar among patients with osteoporosis by spine/hip (17.4%) and radius only (19.1%) (P = .77). FRAX prediction by a regression model using spine/hip T-score yielded explained variance of 51.8% and 49.9% for MOF and 39.8% and 36.4% for hip (with/without trabecular bone score adjustment, respectively). The contribution of 1/3R was statistically significant (P < .001) and slightly increased the explained variance to 52.3% and 50.4% for MOF and 40.9% and 37.4% for hip, respectively.

CONCLUSION

Reclassification of BMD results according to radius measurements results in higher diagnostic output. Prior fractures were equally prevalent among patients with radius-only and classic-site osteoporosis. FRAX tool performance slightly improved by incorporating radius BMD. Whether this approach may lead to a better fracture prediction warrants further prospective evaluation.

Forearm bone density is not elevated in Inuit women with impaired fasting glucose or type 2 diabetes mellitus

Bone mineral density (BMD) and fracture risk are elevated in adults with impaired fasting glucose (IFG) or type 2 diabetes mellitus (T2D). This study aimed to compare bone health among Inuit women with IFG, T2D and normoglycemia. The study included Inuit women (≥40 y) with IFG (n = 57), T2D (n = 72) or normoglycemia (n = 340) from the International Polar Year Inuit Health Survey 2007-2008 in Canada. Distal one-third forearm BMD (FaBMD) was measured using a peripheral instantaneous x-ray imager. Anthropometry, fasting plasma glucose (FPG), serum adiponectin, leptin and 25-hydroxyvitamin D (25(OH)D) were measured. Traditional food intakes were surveyed. Data were analysed using mixed model ANOVA and regression models. The median age was 53 (IFG: IQR 48, 67) y and 56 (T2D: IQR 49, 63) y. Compared to normoglycemic women, FaBMD and T-scores were significantly lower in women with T2D, but not with IFG. Frequency of marine mammal intakes (ß = 0.145; 95%CI: 0.018, 0.053, p = 0.0001) positively related to FaBMD. The odds ratio of having a T-score consistent with osteoporosis was lower among women with T2D and higher BMI, while aging increased the risk. Although T2D associates with lower BMD among Inuit women, risk of osteoporosis is tempered, possibly by maintenance of a traditional lifestyle.

Osteoporosis and osteopenia in the distal forearm predict all-cause mortality independent of grip strength: 22-year follow-up in the population-based Tromsø Study

Low bone mineral density (BMD) gives an increased risk of fractures, which can lead to premature death. Can BMD of the wrist predict mortality? BMD consistent with osteopenia and osteoporosis gave a significantly increased risk of death for both men and women in a general population in Tromsø, Norway.

INTRODUCTION

To investigate if bone mineral density (BMD) levels of the distal forearm, consistent with osteopenia and osteoporosis, can predict mortality and if grip strength is an effect modifier.

METHODS

The study population constituted 6565 participants aged 50-79 years at baseline in the Tromsø Study wave 4 conducted in 1994-1995. Forearm BMD measured by SXA was categorized as "normal," "osteopenia," or "osteoporosis" following WHO's definition. Cox regression with all-cause mortality as the outcome over 22 years of follow-up was performed for men and women separately, adjusting for health-related factors, as well as BMD by grip strength interaction. A secondary analysis with a 15-year follow-up also adjusted for hip fractures and osteoporotic fractures.

RESULTS

During follow-up, 3176 of participants died (47%). Those categorized as osteoporotic had higher mortality hazard ratio (HR) compared to those with normal BMD; men HR = 1.37 (95% confidence interval (CI) 1.19, 1.58) and women HR = 1.32 (1.14, 1.53) were adjusted for age, body mass index, physical activity, smoking habits, education, health status, chronic diseases, and grip strength. Corresponding HRs for osteopenia were men HR = 1.13 (1.00, 1.27) and women HR = 1.17 (1.01, 1.35). Further adjustments for fractures did only marginally attenuate the results, and HRs were still significant. There was no grip strength by BMD interaction.

CONCLUSION

Men and women with low distal forearm BMD values, consistent with osteoporosis or osteopenia, had an increased mortality compared to normal BMD participants. High grip strength did not modify this association, and the association remained after adjustment for a range of health-related factors.

Opportunistic Screening for Osteoporosis Using Computed Tomography: State of the Art and Argument for Paradigm Shift

PURPOSE OF REVIEW

Osteoporosis is disproportionately common in rheumatology patients. For the past three decades, the diagnosis of osteoporosis has benefited from well-established practice guidelines that emphasized the use of dual x-ray absorptiometry (DXA). Despite these guidelines and the wide availability of DXA, approximately two thirds of eligible patients do not undergo testing. One strategy to improve osteoporosis testing is to employ computed tomography (CT) examinations obtained as part of routine patient care to "opportunistically" screen for osteoporosis, without additional cost or radiation exposure to patients. This review examines the role of opportunistic CT in the evaluation of osteoporosis.

RECENT FINDINGS

Recent evidence suggests that opportunistic measurement of bone attenuation (radiodensity) using CT has sensitivity comparable to DXA. More importantly, such an approach has been shown to predict osteoporotic fractures. The paradigm shift of using CTs obtained for other reasons to opportunistically screen for osteoporosis promises to substantially improve patient care.

Volumetric bone mineral density of the spine predicts mortality in African-American men with type 2 diabetes

The study showed that in African-American men with type 2 diabetes mellitus (T2D), vertebral volumetric bone mineral density (vBMD) predicts all-cause mortality, independent of other risk factors for death.

INTRODUCTION

Compared to European Americans, African Americans have lower rates of osteoporosis and higher rates of T2D. The relationships between BMD and fractures with mortality are unknown in this population. The aim of this study was to determine relationships between vertebral fractures and vertebral vBMD and mortality in African Americans with T2D.

METHODS

Associations between vertebral fractures and vBMD with all-cause mortality were examined in 675 participants with T2D (391 women and 284 men) in the African American-Diabetes Heart Study (AA-DHS). Lumbar and thoracic vBMD were measured using quantitative computed tomography (QCT). Vertebral fractures were assessed on sagittal CT images. Associations of vertebral fractures and vBMD with all-cause mortality were determined in sex-stratified analyses and in the full sample. Covariates in a minimally adjusted model included age, sex, BMI, smoking, and alcohol use; the full model was adjusted for those variables plus cardiovascular disease, hypertension, coronary artery calcified plaque, hormone replacement therapy (women), African ancestry proportion, and eGFR.

RESULTS

After mean 7.6 ± 1.8-year follow-up, 59 (15.1%) of women and 58 (20.4%) of men died. In men, vBMD was inversely associated with mortality in the fully adjusted model: lumbar hazard ratio (HR) per standard deviation (SD) = 0.70 (95% CI 0.52-0.95, p = 0.02) and thoracic HR per SD = 0.71 (95% CI 0.54-0.92, p = 0.01). Only trends toward association between vBMD and mortality were observed in the combined sample of men and women, as significant associations were absent in women. Vertebral fractures were not associated with mortality in either sex.

CONCLUSIONS

Lower vBMD was associated with increased all-cause mortality in African-American men with T2D, independent of other risk factors for mortality including subclinical atherosclerosis.