Examining Gender Effects on Time to Fulfillment of Rheumatoid Arthritis Classification Criteria

Gender does not play an outsized role in the classification, diagnosis, and treatment of early rheumatoid arthritis (RA), according to research published in Rheumatology International. However, women with seronegative RA are more likely to experience significant delays.

Researchers compared gender differences in the time to fulfillment of the classification criteria developed by the 1987 and 2010 American College of Rheumatology/European League Against Rheumatism. They also examined the effect of gender on time to initiation of disease-modifying antirheumatic drug (DMARD) therapy.

Data were taken from the Rochester Epidemiology Project, a geographic-based collaborative effort of healthcare facilities across Olmstead County, Minnesota. The participants included adults who developed incident RA between 2009 and 2014 and fulfilled either the 1987 or 2010 American College of Rheumatology/European League Against Rheumatism criteria.

The total study population included 214 patients (148 women; mean age 53.6±15.2 years). In both genders, rheumatoid factor, anticitrullinated protein antibody, obesity, joint involvement, and presence of erosive disease were similar, although men were more likely to be either current or former smokers and more men had abnormal erythrocyte sedimentation rate or C-reactive protein measures. At baseline, 48% of men and 52% of women met the 2010 criteria.

In general, the median time from the first incidence of joint swelling to fulfillment of the 1987 or 2010 classification criteria was not significant across genders (6.5 vs 2.5 days and 1 vs 0 days, P =.48 and P =.34, respectively). Similarly, the median time from joint swelling to clinical diagnosis of either RA or inflammatory arthritis was not significantly different between genders.

In terms of treatment, the median time from initial joint swelling to DMARD or glucocorticoid therapy did not differ by gender (15.5 vs 16 days and 5 vs 9.5 days; P =.90 and P =.70, respectively). Men were slightly more likely to receive methotrexate as their first DMARD (64% vs 61%), but there was no significant difference in choice of first DMARD, use of methotrexate as the first-line DMARD, or starting dose of methotrexate.

Stratifications by rheumatoid factor and anticitrullinated protein antibody status were similar to overall study results. However, among seronegative patients, women were “significantly less likely to meet 2010 criteria at baseline than [men],” according to the results (24% vs 56%; P =.018). Additionally, whereas the delay between the first instance of joint swelling to DMARD initiation was not significantly different, the delay in glucocorticoid treatment initiation was significantly longer in women than in men (60 vs 15 days and 4 vs 0 days; P =.25 and P =.035).

Study limitations included the small sample size, retrospective study design, and lack of generalizability to ethnically and geographically diverse populations.

“The results of this study … suggest that previously described differences in the RA disease course between [men] and [women] patients are likely due to factors other than treatment delay, and further study is needed to improve gender-specific outcomes in RA,” the researchers concluded.

Reference

Coffey CM, Davis JM III, Crowson CS. The impact of gender on time to rheumatoid arthritis classification: a retrospective analysis of a population-based cohort [published online July 23, 2019]. Rheumatol Int. doi: 10.1007/s00296-019-04360-2