REDUCED risk of cardiovascular events has been associated with sustained treatment with biologics or TNF inhibitors in patients with rheumatoid arthritis (RA), psoriatic arthritis (PsA), and ankylosing spondylitis (AS). One of the motivating factors behind this study was that RA, PsA, and AS are also associated with an increased risk of cardiovascular events. As this increased risk is speculated to result from systemic inflammation, it was hypothesised that treatment with TNF inhibitors would lower cardiovascular risk by reducing inflammation.
The patients included in this cohort study were consecutive participants with RA, PsA, or AS in the Australian Rheumatology Association (ARA) Database from September 2001–January 2015. A total of 4,140 patients comprised the analysis, encompassing 19,627 patient years. The study’s definition of a cardiovascular event was death from cardiovascular causes, including angina, myocardial infarction, coronary artery bypass graft, percutaneous coronary intervention, other heart disease, and stroke/transient ischaemic attack. The researchers used the Cox proportional hazards model with the counting process and time-varying covariates for their analysis.
Adjustments were made for a number of factors, including age, sex, hypertension, diabetes, and methotrexate use. Following adjustment, cardiovascular event risk was reduced with TNF inhibitor use (hazard ratio [HR]: 0.85; 95% confidence interval [CI]: 0.76–0.95) and also with the use of other biologic therapies (HR: 0.81; 95% CI: 0.70–0.95). However, if a patient had halted biologic therapy, there was no reduction in the risk of a cardiovascular event (HR: 0.96; 95% CI: 0.83–1.11).
The researchers noted: “These findings support the hypothesis that control of systemic inflammation in these conditions may reduce the treatment risk”, which is an encouraging finding for those seeking to reduce the risk of cardiovascular events in patients with RA, PsA, and AS. However, researchers also pointed out that this research was an observational study and, as such, showed association rather than causation. A suggested alternative explanation of the study results was that perhaps the rheumatologists had prescribed biologics for healthier patients.