Medline ® Abstract for Reference 40
of 'Risk factors for and possible causes of osteoarthritis'
Estrogen replacement therapy and the development of osteoarthritis.
Oliveria SA, Felson DT, Klein RA, Reed JI, Walker AM
Recent studies have indicated that estrogen users have a lower than expected rate of concurrent osteoarthritis. We assessed the association between estrogen replacement therapy and incident symptomatic osteoarthritis, using a nested case-control design. We identified all incident cases of hand, hip, and knee osteoarthritis in women members of the Fallon Community Health Plan, age 20-89 years, from January 1, 1990, to December 31, 1993. For each case, we selected a control woman matched by closest date of birth. We used pharmacy records to classify women as new users, past users, ongoing users (past and new users), and never-users of estrogen replacement therapy. There were 60 informative case-control pairs. After controlling for obesity and health care utilization, we found that new use of estrogen replacement therapy was a predictor of new osteoarthritis diagnosis. Past use was inversely associated with risk of osteoarthritis [adjusted odds ratio = 0.7; 95% confidence interval (CI) = 0.3-1.9]. For ongoing use of estrogen replacement therapy and osteoarthritis, the adjusted odds ratio was 1.4 (95% CI = 0.6-3.3). The associations between osteoarthritis and both new use of estrogen replacement therapy and utilization of services suggest that frequent medical care increases the likelihood of diagnosis of osteoarthritis.
Department of Epidemiology, Harvard School of Public Health, Boston, MA, USA.