Is there a sex bias in prescribing anti-tumour necrosis factor medications to patients with rheumatoid arthritis? A nation-wide cross-sectional study.

OBJECTIVES:To determine whether men and women with rheumatoid arthritis are prescribed anti-tumour necrosis factor (anti-TNF) treatment at different levels of disease activity. METHODS:Data from the Swedish national biologics registry ARTIS were used to analyse characteristics of patients' disease at the start of the first anti-TNF treatment. Means for men and women were compared using t-tests, and non-normally distributed covariates were compared using the Wilcoxon rank-sum test. Linear regression models, adjusted for age and calendar year, were used to investigate the association between sex and each disease activity measurement. RESULTS:Women were younger and had longer disease duration at treatment start than men. Tender joint count, erythrocyte sedimentation rate, patient's global assessment, patient-reported pain and health assessment questionnaire scores were significantly higher in women, whereas men had a higher level of C-reactive protein (p<0.05 for all comparisons). Swollen joint count and physician's global assessment did not differ by sex. CONCLUSIONS:For women with rheumatoid arthritis, treatment with anti-TNF therapy was initiated at a higher level of subjective disease activity than for men, but at the same level of physician-reported disease activity. These data imply that patients' subjectively experienced disease activity may be discounted in the treatment decision.