Anti-drug antibody (ADA) testing for biologics, particularly anti–tumor necrosis factor (TNF) agents, has been commercially available for several years, though its clinical use in rheumatoid arthritis (RA) is not known owing to lack of prospective data. Bitoun and colleagues analyzed data from the European ABI-RA registry to evaluate the association between ADA and the anti–TNF monoclonal antibodies (mAb) etanercept, tocilizumab, and rituximab, and clinical response (as measured by disease activity scores, inflammatory markers, and European Alliance of Associations for Rheumatology [EULAR] response rate). Higher rates of ADA positivity were seen in patients treated with rituximab (50%), anti-TNF mAb (38%), and tocilizumab (20%) compared with etanercept (6%). Patients who had a positive ADA test were less likely to have a EULAR response. In addition, patients treated with methotrexate were less likely to have persistent ADA. Though the study was not powered enough to detect differences between the drug classes, the evidence presented is compelling and suggests a role for measuring ADA in patients with RA who do not respond to treatment.
RA is well-known to be associated with cardiovascular disease, particularly atherosclerotic disease and heart failure, but its association with valvular heart disease and its progression has not been well-explored in the literature. Johnson and colleagues performed a cohort study of over 73,000 patients with RA in the Veterans Health Administration (VHA) system compared with 640,000 patients without RA to evaluate the incidence of aortic stenosis, need for intervention, and risk for death. Though the overall incidence rate was low (about 3%), patients with RA had a higher risk for aortic stenosis, with a hazard ratio of 1.48 compared with those without RA, as well as a higher risk for aortic valve replacement and aortic stenosis–related death. The risk for aortic stenosis was associated with hypertension, stroke, and other cardiovascular disease, as well as a body mass index > 30 kg/m2, although not with a history of smoking or diabetes. Because the study was performed using data from the VHA — that is, from predominantly male patients — this finding may not be generalizable. In addition, the diagnosis of aortic stenosis is generally reliant on echocardiography and may be detected while searching for other conditions not evaluated here (such as pericarditis). As such, these findings would not support routine screening in patients with RA without other reasons for suspicion of valvular heart disease.
In particular, the increase in cardiovascular risk associated with glucocorticoid therapy in patients with RA has received increased scrutiny, along with other side effects of systemic glucocorticoids. In a recent retrospective study, So and colleagues examined the clinical data of over 12,000 patients with RA treated in public hospitals in Hong Kong with a mean of 9 years of follow-up. Consistent with prior studies, systemic glucocorticoid use (prednisolone equivalent > 5 mg daily) was associated with an increased risk for adverse cardiovascular events, whereas lower doses did not increase cardiovascular risk. Because the data on some disease activity measures and traditional cardiovascular risk factors (such as smoking or obesity) were not available in the database, the study supports, but does not expand on, prior evidence regarding cardiovascular risk.
Almayali and colleagues also looked at glucocorticoid therapy in RA in a follow-up study to the previously published pragmatic randomized double-blinded placebo-controlled GLORIA study, which evaluated the effects of 5 mg/d prednisolone added to standard care for 2 years in patients with active RA who were age 65 years or older. In the current study, 191 patients out of the initial 451 were followed for 3 months and prednisolone tapered off. Patients who tapered off prednisolone had, as expected, an increased risk for flare but no evidence of adrenal insufficiency. Although, again, this is not likely to change practice, it does suggest that glucocorticoid tapering is a reasonable goal in RA therapeutic trials.