According to results from a matched prospective cohort study within the Nurses’ Health Study (NHS), women with rheumatoid arthritis (RA) had an increased risk for chronic obstructive pulmonary disease (COPD) but did not have an increased risk for asthma compared with women without RA. These findings were published in Seminars in Arthritis and Rheumatism.
Between 1976 and 2014, a total of 121,701 women from an incident RA cohort within the NHS were identified. Each of the women with RA was matched with 10 comparators without RA based on age and year at index data of RA diagnosis. Women who had asthma or COPD at baseline were excluded from the study. Data were obtained from medical records and biennial questionnaires.
A total of 843 women with RA were ultimately identified and matched with 8399 comparator participants without RA. Mean patient age was 59.8 years; mean follow-up after index date was 18.6±9.0 years in women with RA and 18.8±9.5 years in women without RA.
Overall, among women with RA, incident COPD occurred in 8.1% (68 of 843) and asthma occurred in 4.7% (40 of 843). Rates of COPD and asthma in women without RA were 5.5% (459 of 8399) and 3.2% (268 of 8399), respectively.
RA was associated with an increased risk for COPD (hazard ratio [HR], 1.52; 95% CI, 1.17-1.97) and asthma (HR, 1.55; 95% CI, 1.11- 2.16) vs comparator participants without RA.
When additional adjustments were applied, such as confounders and time-varying mediators that occurred following the index date, including smoking, RA in women was significantly associated with COPD (HR, 1.68; 95% CI, 1.36- 2.07) but not with asthma (HR, 1.11; 95% CI, 0.59- 2.59) compared with non-RA participants.
In multivariable analysis based on serostatus, both seropositive RA (HR, 1.74; 95% CI, 1.36-2.23) and seronegative RA (HR, 1.62; 95% CI, 1.09-2.04) were significantly associated with an increased risk for COPD vs comparators without RA.
Worsened COPD-free survival was statistically significant for all RA (P <.001), for seropositive RA (P <.001), and for seronegative RA (P =.017) compared with non-RA in weighted cumulative survival curves.
The investigators concluded that RA-specific factors may predispose individuals to developing COPD independent of smoking. Screening and early treatment of respiratory illnesses in patients with RA may therefore help to decrease the respiratory burden of the disease.
Sparks JA, Lin T-C, Camargo CA Jr, et al. Rheumatoid arthritis and risk of chronic obstructive pulmonary disease or asthma among women: a marginal structural model analysis in the Nurses’ Health Study [published online September 18, 2017]. Semin Arthritis Rheum. pii:S0049-0172(17)30382-7. doi:10.1016/j.semarthrit.2017.09.005