Nonlinear association between bone mineral density and all-cause mortality: the Dong-gu study

The Association between Bone Mineral Density and Risk of Mortality: A Prospective Cohort Study of 233,397 Taiwanese

PURPOSE

Osteoporosis is an important public health challenge given its high prevalence in western populations and the prevalence has shown an upward trend in recent decades in Asia. However, epidemiological evidence on the association between bone mineral density (BMD) and mortality risk in the Asian population is sparse.

METHODS

The Cox proportional hazards model and cause-specific hazard models were used to investigate the association of BMD with the risk of all-cause mortality and cause-specific mortality.

RESULTS

The present study comprised of 3,332,207 person-years with a median follow-up of 14.6 years. 27,508 participants (15,967 men and 11,541 women) died among 233,397 participants (112,348 men and 121,049 women) during the follow-up period. Compared to those with normal BMD level, both men and women with low BMD had a significantly higher risk of all-cause, cardiovascular disease (CVD), and cancer mortality after adjusting for the covariates. [For men with osteoporosis: all-cause: 1.37 (1.27-1.49); CVD: 1.28 (1.08-1.52); cancer: 1.29 (1.12-1.49); For women with osteoporosis: all-cause: 1.72 (1.63-1.82); CVD: 1.85 (1.64-2.08); cancer: 1.47 (1.35-1.61)]. The P for interactions for BMD with sex were significant for all-cause and CVD mortality. The adverse effects of BMD on the risk of all-cause and CVD were higher in women than in men [men vs. women: all-cause: 1.37 (1.27-1.49) vs. 1.72 (1.63-1.82); CVD: 1.28 (1.08-1.52) vs. 1.85 (1.64-2.08)]. In the nonlinear dose-response analyses, the association between BMD increments and all-cause mortality risk shows an L-shaped pattern in men and a similar U-shaped trend in women (P for non-linear association: <0.001). Likewise, a similar L-shaped association was observed between BMD levels and cancer mortality risk in men.

CONCLUSIONS

Low BMD had an increased risk of all-cause, CVD, and cancer mortality in both men and women. Women had a stronger positive association between low BMD and an increased risk of all-cause and CVD mortality compared to men.

Bone mineral density and osteoporosis in relation to all-cause and cause-specific mortality in NHANES: A population-based cohort study

OBJECTIVE

The majority of the published studies ascertaining the relationships between low bone mineral density (BMD) and mortality highlighted the elderly population with limited sample size. Our study aimed to ascertain the relationships in general population.

METHODS

This study ascertained the relationships between BMD levels in femur and lumbar spine with all-cause and cause-specific mortality in the National Health and Nutrition Examination Survey (NHANES) (n = 15,076, mean age 48.6 years). Cox proportional hazards models were adopted to calculate the hazard ratios (HR) and the corresponding 95% confidence intervals (CIs) for mortality.

RESULTS

During a 6.8-year median follow-up, 1216 men and women in the cohort died. There was a higher risk of all-cause mortality among participants with osteoporosis compared with normal in the regions of total femur (HR = 1.36, 95% CI = 1.07-1.73), femur neck (HR = 1.41, 95% CI = 1.11-1.78), intertrochanter (HR = 1.34, 95% CI = 1.05-1.72), as well as overall (HR = 1.36, 95% CI = 1.09-1.69). Non-linear dose-response analyses showed a statistically significant L-shaped association for all-cause mortality with BMD increment in the regions of total femur, femur neck, trochanter, and intertrochanter. The protective role of higher BMD level in femur for decreased risk of cancer mortality and heart diseases mortality was more evident in male participants and female participants, respectively.

CONCLUSIONS

In summary, our results revealed that maintaining normal BMD is critical to lower the risk of mortality. The association between higher BMD level in femur and decreased risk of cancer as well as heart diseases mortality varies by gender.

Oral Bisphosphonate use Reduces Cardiovascular Events in a Cohort of Danish Patients Referred for Bone Mineral Density

CONTEXT

The cardiovascular (CV) safety of oral bisphosphonates (oBPs) is uncertain.

OBJECTIVE

Determine the risk of CV events in oBP users referred for bone mineral density (BMD) testing compared with matched controls.

DESIGN

Cohort study.

SETTING

Danish national prescription registry enriched with local hospital data from Odense.

PARTICIPANTS

Individuals aged ≥45 years referred for BMD testing.

EXPOSURE

oBP.

OUTCOMES

Hospitalization for any CV event. Secondary study outcomes were specific CV events. Negative (inguinal hernia surgery and ingrown toenail) and positive (fragility fracture) control outcomes assessed systemic bias. Cox proportional hazards models were fitted to estimate hazard ratio (HR) and 95% confidence intervals.

RESULTS

There were 2565 oBP users (82.6% women) and 4568 (82.3% women) propensity score-matched controls. Alendronate accounted for 96% of oBP prescription. A total of 406 (15.8%) CV events occurred in oBP users (rate = 73.48 [66.67-80.98]); rate = events divided by person-time; and 837 (18.3%) events in controls (rate = 104.73 [97.87-112.07]) with an adjusted HR of 0.68 (95% CI 0.60-0.77). Additional adjustment for BMD did not attenuate estimates (HR 0.67; 95% CI 0.58-0.78]. Similar results were seen for secondary outcomes where risk reductions were seen regarding atrial fibrillation, stroke, heart failure, and aneurysms. Positive and negative control outcome analyses identified minimal residual confounding.

CONCLUSION

Oral BP users experienced a 33% reduced risk of CV events. This observational real-world study adds to a growing body of evidence for cardioprotection by oBP that warrants testing in a randomized setting.

Association of Heel Bone Mineral Density With Incident Disability and Mortality in Community-Dwelling Older Adults

Age‐related bone loss is common in older adults. However, the association of low bone mass with incident disability and mortality is not well established. A sample of 738 participants in the Rush Memory and Aging Project (MAP) was evaluated at baseline for bone mineral density (BMD) using quantitative ultrasound at the calcaneus. An annual interview assessed basic activities of daily living (BADL), instrumental activities of daily living (IADL), mobility disability, and history of hip fracture. The associations between baseline BMD and risk of death; incident BADL, IADL, and mobility disability; and hip fracture were investigated using Cox hazard models, adjusting for age, sex, education, race, and body mass index (BMI). The robustness of our findings was evaluated by adjusting for confounding factors and health conditions including joint pain, musculoskeletal medications, smoking status, motor function, global cognition, falls, cardiovascular events, and diabetes. Participants were on average (mean ± SD) 80.9 ± 7.0 years old, 72% female, and 3.8% black, with a baseline BMI of 27.3 ± 5.4 kg/m², and a baseline of BMD of 0.44 ± 0.14 g/cm². In models adjusted for age, sex, education, race, and BMI, lower BMD was associated with a higher rate of death (hazard ratio [HR] 1.20; 95% confidence interval [CI], 1.08–1.33), incident BADL disability (HR 1.20; 95% CI, 1.05–1.37), and hip fracture (HR 2.57; 95% CI, 1.72–3.82), but not of IADL disability (HR 1.00; 95% CI, 0.85–1.17) or mobility disability (HR 1.13; 95% CI, 0.97–1.32). The association between BMD and mortality was not significant in fully adjusted models, but the BMD and BADL associations remained significant in models adjusting for both demographic variables and BMD‐modifying health conditions. BMD is associated with incident disability in older adults. © 2020 The Authors. JBMR Plus published by Wiley Periodicals LLC on behalf of American Society for Bone and Mineral Research.