Although rheumatoid arthritis (RA) is well understood to be associated with cigarette smoking as well as with a risk for interstitial lung disease (ILD), its association with airway diseases such as asthma and chronic obstructive pulmonary disease (COPD), and with allergic disorders such as atopic dermatitis and allergic rhinitis, is unknown. Kim and colleagues performed a cross-sectional study using information from the Korean National Health and Nutrition Examination Survey by 334 respondents with RA and over 13,000 respondents without RA and analyzed the association of RA with asthma and asthma-related comorbidities. The prevalence of asthma was higher in respondents with RA (7.5% vs 2.8%; P < .001), but the prevalence of other allergic disorders and COPD wassimilar between groups. This finding in a small group of respondents is not striking and its importance is unclear compared with other nonallergic pulmonary disorders. Inferring a mechanistic connection to T-helper (Th) 1- vs Th2 immunity would thus be premature.
Baker and colleagues examined the risk for RA-associated ILD in patients taking different therapies for RA, a topic of great interest due to the frequency of this complication as well as uncertainty regarding its association with medications, including anti-tumor necrosis factor (TNF) agents and methotrexate. Using a claims database, they performed a retrospective study of patients with RA without existing ILD who were treated with a biologic (b) or targeted synthetic disease-modifying antirheumatic drugs (DMARD; abatacept, adalimumab, rituximab, tocilizumab, and tofacitinib). In over 28,000 patients with RA, incidence ratios for ILD were > 1 for all bDMARD, while the incidence ratio for ILD with tofacitinib was 1.47. As the group of patients treated with tofacitinib was the smallest, the reliability of this result is uncertain and thus not strong enough to suggest a protective effect or preference for this medication in patients with known ILD. However, prospective studies looking at ILD in RA patients taking tofacitinib would be of interest.
Kristensen and colleagues also looked at risks associated with tofacitinib and anti-TNF agents, in particular cardiovascular disease, malignancy, and venous thromboembolism, using data from the open-label randomized ORAL Surveillance study, which looked at patients taking 5 mg or 10 mg tofacitinib twice daily, adalimumab, or etanercept. The 10 mg dose was reduced to 5 mg twice daily after it was found that rates of pulmonary embolism were higher in the group taking the higher dose. Age and smoking are also known to be risk factors for malignancy and cardiovascular disease in patients with RA, and these findings carried through in this analysis as well. Within the study, patients taking tofacitinib over age 65 who had ever smoked had a higher risk for cardiovascular events, myocardial infarction, malignancy, venous thromboembolism, and death compared with patients on anti-TNF therapy, while patients taking tofacitinib who were younger than 65 and had never smoked had a risk similar to those on anti-TNF therapy.The study confirms prior knowledge regarding the risks of tofacitinib in different patient populations, suggesting that caution should be used with this medication in older patients and those who smoke.