The Association of Mitral Annular Calcification With Cardiovascular and Noncardiovascular Outcomes: The Multi-Ethnic Study of Atherosclerosis

Mitral annular calcification (MAC) may be a potential marker of biologic aging. However, the association of MAC with noncardiovascular measures, including bone mineral density (BMD), incident renal failure, dementia, and noncardiovascular mortality, is not well-studied in a multiracial cohort. We used data from 6,814 participants (mean age: 62.2 ± 10.2 years, 52.9% women) without cardiovascular disease at baseline in the Multi-Ethnic Study of Atherosclerosis. MAC was assessed with noncontrast cardiac computed tomography at study baseline. Using multivariable-adjusted linear and logistic regression, we assessed the cross-sectional association of MAC with BMD and walking pace. Furthermore, using Cox proportional hazards, we evaluated the association of MAC with incident renal failure, dementia, and all-cause mortality. In addition, we assessed the association of MAC with cardiovascular and noncardiovascular mortality using competing risks regression. The prevalence of MAC was 9.5% and was higher in women (10.7%) than in men (8.0%). MAC was associated with low BMD (coefficient −0.04, 95% confidence interval [CI] −0.06 to −0.02), with significant interaction by gender (p-interaction = 0.035). MAC was, however, not associated with impaired walking pace (odds ratio 1.09, 95% CI 0.89 to 1.33). Compared with participants without MAC, those with MAC had an increased risk of incident renal failure, albeit nonsignificant (hazard ratio [HR] 1.18, 95% CI 0.95 to 1.45), and a significantly higher hazards of dementia (HR 1.36, 95% CI 1.10 to 1.70). In addition, participants with MAC had a substantially higher risk of all-cause (HR 1.47, 95% CI 1.29 to 1.69), cardiovascular (subdistribution HR 1.39, 95% CI 1.04 to 1.87), and noncardiovascular mortality (subdistribution HR 1.35, 95% CI 1.14 to 1.60) than those without MAC. MAC ≥100 versus <100 was significantly associated with reduced BMD, incident renal failure, dementia, all-cause, cardiovascular, and noncardiovascular mortality. In conclusion, MAC was associated with reduced BMD and dementia and all-cause, cardiovascular, and noncardiovascular mortality in this multiracial cohort. Thus, MAC may be a marker not only for atherosclerotic burden but also for other metabolic and inflammatory factors that increase the risk of noncardiovascular outcomes and death from other causes.