Oral Contraceptives May Protect Against Rheumatoid Arthritis

Investigators found that oral contraceptives (OC) use may offer protective benefits against rheumatoid arthritis (RA), according to a study published in Rheumatology.

This study aimed to assess the effects of exogenous sex hormones, specifically OC and menopausal hormone therapy (MHT), on the development of RA. While OCs and MHT are commonly used worldwide, their influence on RA risk remains debated, with prior research suggesting potentially opposite effects. Researchers sought to clarify the relationship between OC use and RA development during a woman's reproductive years, as well as the link between MHT and late-onset RA (LORA) later in life.

The analysis was conducted using time-dependent Cox regression models on data from White British women in the UK Biobank, with a sample size of 236,602 for OC use and 102,466 for MHT use. The findings were also validated across women of all ethnic groups. Results revealed that OC use was associated with a decreased risk of RA, with ever-users showing a hazard ratio (HR) of 0.89 compared to never-users. Current users (HR = 0.81) and former users (HR = 0.92) of OCs also had a lower risk of developing RA.

In contrast, MHT use was linked to an increased risk of LORA, with ever-users having a hazard ratio of 1.16 compared to never-users. Former MHT users showed a slightly lower, but still elevated, risk (HR = 1.13).

In conclusion, the study suggests that OC use may offer protective benefits against RA, while MHT may elevate the risk of LORA, highlighting the complex and divergent effects of different exogenous sex hormones on RA risk.

Reference
Hadizadeh F, Johansson T, Johansson Å, Karlsson T, Ek WE. Effects of oral contraceptives and menopausal hormone therapy on the risk of rheumatoid arthritis: a prospective cohort study. Rheumatology (Oxford). 2024;63(8):2101-2108. doi:10.1093/rheumatology/kead513