Serious infection risk of tofacitinib compared to biologics in patients with rheumatoid arthritis treated in routine clinical care.

Recently, serious infections related to the use of tofacitinib (TOF) for treatment of rheumatoid arthritis (RA) have raised considerable interest. This study aimed to compare the risk for serious infections in patients with RA upon receiving TOF versus biologic disease-modifying antirheumatic drugs (bDMARDs) by age at treatment initiation. We identified adult RA patients exposed to TOF or bDMARDs using data collected by the Swiss registry for inflammatory rheumatic diseases (SCQM) from 2015 to 2018. The event of interest was the first non-fatal serious infection (SI) during drug exposure. Missing or incomplete SI dates were imputed as either the lower (left) or upper (right) limit of the known occurrence interval. The ratio of SI hazards (HR) of TOF versus bDMARDs was estimated as a function of age using covariate-adjusted Cox regression applied to each type of imputed time-to-SI. A total of 1687 patients provided time at risk for a first SI during study participation and drug exposure for 2238 different treatment courses, 345 for TOF and 1893 for bDMARDs. We identified 44 (left imputation) or 43 (right imputation), respectively, first SIs (12/12 on TOF versus 32/31 on bDMARDs). Left and right imputation produced similar results. For patients aged ≥ 69 years, the treatment HR started to be increased (lower limit of 95% confidence intervals (LLCIs) > 1). By the age of 76, the difference between TOF and bDMARDs started to be clinically relevant (LLCIs > 1.25). For patients aged < 65 years, the data were insufficient to draw conclusions. Our results suggest that we should expect an increased risk for SIs in older patients treated with TOF compared to bDMARDs supporting a cautious use of TOF in these patients.

Female hormonal factors and the development of anti-citrullinated protein antibodies in women at risk of rheumatoid arthritis.

Objectives: To analyse the association between female hormonal factors and the development of systemic autoimmunity associated with RA in women at increased risk for RA, namely first-degree relatives of patients with RA (RA-FDRs). Methods: In an ongoing cohort study of RA-FDRs, we analysed all women with available ACPA status. The primary outcome was ACPA positivity. The predictors of interest were female hormonal factors, such as oral contraceptives, breastfeeding, post-menopausal status, early post-menopausal period and total number of ovulatory years. Results: A total of 768 female RA-FDRs were analysed, of which 42 (5%) had developed ACPA positivity. ACPA-positive women were older (52 vs 44 years, P = 0.001). Hormonal factors significantly and independently associated with the presence of ACPA were the post-menopausal (P < 0.001) and the early post-menopausal periods (P = 0.040). Conclusions: In women at increased risk of RA, characteristic systemic autoimmunity was associated with menopause, suggesting that the acute decline in ovarian function might contribute to the development of autoimmunity associated with RA and potentially to the increased risk of RA in women.

The prevalence of anticitrullinated protein antibodies increases with age in healthy individuals at risk for rheumatoid arthritis.

Transition from genetic risk to the development of systemic autoimmunity associated with rheumatoid arthritis (RA) is considered a key step for the development of RA and often referred to as the immune onset of the disease. The aim of this study is to identify predictors for the presence of anticitrullinated protein antibodies (ACPA) as a marker of systemic autoimmunity associated with RA in a high-risk population, an ongoing cohort of first-degree relatives of patients with RA. We assessed the presence of ACPA in individuals without clinical evidence of RA. We examined characteristics associated with ACPA positivity using general estimation equations to account for multiple observations per individual. A total of 1159 serum samples from 1025 subjects were analyzed, 69 samples (6%) were ACPA-positive, and 227 (20%) positive for rheumatoid factor. Participants had a median age of 45 years (interquartile range (IQR): 33-55) at baseline and 76% were women. Overall, ACPA positivity increased with age (p < 0.001). Among women, ACPA positivity was particularly associated with the age group 45 to 55 years (p = 0.003), but not among men (p = 0.7). In multivariable adjusted analyses, age older than 45, female sex and tobacco smoking were independently associated with ACPA positivity. In our cohort, the presence of ACPA was associated with older age and peaked in women around age 45 to 55 years, the perimenopausal period, suggesting that the development of ACPA may be favored by the decline in ovarian function.

Increased concentrations of antibody-bound circulatory cell-free DNA in rheumatoid arthritis.

BACKGROUND: Increased concentrations of cell-free DNA have been found in several disorders and have been interpreted as evidence of increased rates of cell death or turnover. Evidence from in vitro and animal experiments suggests that DNA may play a role in the pathogenesis of rheumatoid arthritis (RA). METHODS: We measured cell-free DNA in plasma and serum from patients with RA and healthy controls by use of quantitative PCR for glyceraldehyde-3-phosphate dehydrogenase (GAPDH) DNA. We used protein G Sepharosetrade mark bead adsorption of plasma and elution to isolate antibody-bound DNA. RESULTS: In paired plasma and serum samples of 16 healthy controls the median GAPDH copies were 4500 genome equivalents (GE)/mL plasma (range 319-21 000) and in 26 RA patients 17 000 GE/mL plasma (2100-2 375 000, P = 0.0001). In the serum from normal controls the median GAPDH copies were 35 000 GE/mL (1700-239 000) and from RA patients 222 000 GE/mL (21 000-2 375 000, P = 0.004). A median of 81% of the cell-free DNA in RA was associated with antibody compared with 9% in healthy controls (P = 0.001). The concentrations of DNA did not vary with the type of therapy patients received. CONCLUSIONS: These results provide new evidence for a role of cell-free DNA-antibody complexes in the etiology of RA, suggest new avenues for basic research, and may prove to be relevant to diagnosis and assessment of therapy.