Impact of osteoporosis risk on in-hospital mortality in older patients with acute myocardial infarction: Insight from Tokyo CCU network database.

Background: Osteoporosis and cardiovascular disease often coexist in older adults, yet the prognostic impact of osteoporosis risk on outcomes of acute myocardial infarction (MI) remains unclear. This study aimed to investigate the prevalence of high osteoporosis risk and its association with in-hospital mortality among older patients with acute MI. Methods: We analyzed 8591 consecutive patients admitted with acute MI and registered in the Tokyo CCU Network Database between 2021 and 2022. Patients were stratified into tertiles according to OST values, separately for men and women. The primary outcome was in-hospital all-cause mortality. Multivariate logistic regression, forest plots, and restricted cubic spline models were applied to assess the association between OST and the primary outcome. Results: According to the OST criteria, 23.1 % (1503/6493) of men and 85.3 % (1791/2098) of women were classified as high risk for osteoporosis. Among those aged ≥65 years, 39.2 % (1500/3828) of men and 95.2 % (1717/1804) of women were classified as high risk. In-hospital all-cause mortality rates were 2.9 % in OST Tertile 1, 4.0 % in Tertile 2, and 10.0 % in Tertile 3 (p < 0.001). After multivariable adjustment, OST Tertile 3 remained independently associated with increased in-hospital mortality (adjusted odds ratio 2.08; 95 % CI, 1.44-3.01) compared with Tertile 1. Conclusions: High osteoporosis risk, as estimated by the OST, was common and independently associated with increased in-hospital mortality among patients with acute MI. These findings suggest that simple screening for osteoporosis risk may help identify vulnerable older adults at higher risk of adverse outcomes following acute MI.