An examination of the association betweeen bone mineral density and mortality in older men

PURPOSE: This study investigated the relationship between bone mineral density (BMD) and mortality in men using data from the NHANES I Epidemiologic Follow-up Study, which tracked participants from enrollment in 1971–1974 through 1992. METHODS: This analysis included 1,130 men aged 50–74 when first contacted for NHANES I in 1971–1974 who had baseline BMD measurements as part of their first NHANES visit. Mortality rates were calculated by age-adjusted quartile of BMD. RESULTS: Tests for trend showed that lower baseline BMD was significantly associated with total (p < 0.0001), cardiac (p = 0.0213), and cancer (p = 0.0034) mortality. After adjusting for potential confounders (age, cigarettes/day, BMI, exercise, systolic blood pressure, diabetes, serum cholesterol, and race), Cox proportional hazards analyses revealed that lower BMD was associated with cardiac mortality only in the first three years of follow up, while the association between lower BMD and all-cause or cancer mortality persisted through 14 years of follow-up. CONCLUSIONS: We conclude that low BMD appears to be a marker for cardiac and cancer mortality; delineation of the causal pathway awaits further studies.