Association between metabolic syndrome and osteoporosis among adults aged 50 years and older: using the National Health Information Database in South Korea

Summary This study aimed to examine the association between a history of metabolic syndrome (MetS) and osteoporosis with specific characteristics. The results showed that MetS was inversely associated with osteoporosis. In contrast, MetS was positively associated with osteoporosis in both obese men and postmenopausal obese women. Purpose Although several previous studies have investigated the association between MetS and osteoporosis, their findings remain controversial. This study aimed to examine the association between a MetS history and osteoporosis using a subset of data from a large, long-term, national database. Methods This nested case–control study used the National Health Information Database (NHID) of the Korea National Health Insurance Service (NHIS) from 2009 to 2017. Osteoporosis ( n = 459,771) and control ( n = 459,771) participants were matched in a 1:1 ratio by age, gender, income, and region of residence. MetS was defined based on the modified National Cholesterol Education Program-Adult Treatment Panel III criteria. Crude and adjusted odds ratios (ORs) with 95% confidence intervals (CIs) for osteoporosis in patients with MetS and its components were analyzed using logistic regression. Subgroup analyses were performed according to the combination of gender, menopausal status, and obesity status. Results The adjusted OR (95% CI) for osteoporosis in patients with MetS was 0.95 (0.94–0.96). This finding was consistent with the subgroup analyses in normal weight men, premenopausal (pre-MP) women with all obesity statuses, and postmenopausal (post-MP) underweight and normal weight women. In contrast, the opposite was observed for obese men (OR = 1.05, 95% CI = 1.01–1.09) and post-MP obese women (OR = 1.05, 95% CI = 1.01–1.08). Conclusion This study results suggested that MetS was associated with a low occurrence of osteoporosis. In contrast, MetS was associated with a high occurrence of osteoporosis in both obese men and post-MP obese women.