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

ABSTRACT

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.