Knee osteoarthritis and menopausal hormone therapy in postmenopausal women: a nationwide cross-sectional study

Objective: The incidence of osteoarthritis (OA) increases after menopause, and may be related to hormonal changes in women. Estrogen deficiency is known to affect the development of OA, and menopausal hormone therapy (MHT) is suggested to be related to the development of OA. However, the relationship between knee OA and MHT remains controversial. The association between knee OA prevalence and MHT was investigated using large-scale national data. Methods: Data were collected from 4,766 postmenopausal women from the Korea National Health and Nutrition Examination Survey (2009-2012). MHT was defined as regular hormone medication for >= 1 year, and demographic and lifestyle variables were compared between the MHT and non-MHT groups. Knee OA was defined according to symptoms and radiographic findings. Results: In the multiple logistic regression models, the OA odds ratio was 0.70 for the MHT group (95% confidence interval 0.50-0.99), compared with the non-MHT group. Conclusions: The prevalence of knee OA was lower in participants with MHT than in those without MHT.