Oral Contraceptives May Protect Against Rheumatoid Arthritis
WEDNESDAY, Nov. 8, 2023 (HealthDay News) -- Oral contraceptive use appears to protect against rheumatoid arthritis (RA), while menopausal hormone therapy (MHT) use may increase the risk for late-onset RA, according to a study published online Sept. 29 in Rheumatology.
Fatemeh Hadizadeh, M.D., Ph.D., from Uppsala University in Sweden, and colleagues estimated the effects of exogenous hormones on the development of RA, both during the reproductive lifespan and later in life. The analysis included 236,602 oral contraceptive users and 102,466 MHT users participating in the U.K. Biobank.
The researchers found that oral contraceptive use was associated with a decreased risk for RA in ever-users (hazard ratio [HR], 0.89; 95 percent confidence interval [CI], 0.82 to 0.96). The association was seen in both current (HR, 0.81; 95 percent CI, 0.73 to 0.91) and former users (HR, 0.92; 95 percent CI, 0.84 to 1.00) versus never-users. MHT use was associated with an increased risk for late-onset RA in ever-users (HR, 1.16; 95 percent CI, 1.06 to 1.26), as well as in former users (HR, 1.13; 95 percent CI, 1.03 to 1.24) versus never-users.
"The observed presence of two distinct effects of exposure to exogenous hormones on risk of RA could be related to differences in the hormones' functions in the body, variations in the response to hormones in different reproductive statuses, or heterogeneity between early-onset RA and late-onset RA," the authors write.