Adhering to TNFi Therapy May Reduce Joint Replacement Rates in Rheumatoid Arthritis

The National Institute for Health and Care Excellence (NICE) guidance on the approval of tumor necrosis factor inhibitor (TNFi) therapies for the management of rheumatoid arthritis (RA) in England and Wales has demonstrated a temporal association with reduced rates of total knee replacement (TKR) surgery, but not total hip replacement (THR) surgery, according to the results of a recent study published in Seminars in Arthritis & Rheumatism.  

The investigators used primary care health data gathered between 1995 and 2014 to identify adult patients with incident RA. NICE recommended the use of TNFi therapies (specifically, etanercept and infliximab) for treatment in adults with severe RA (Disease Activity Score [DAS] >5.1) who had not responded to 2 conventional synthetic disease-modifying antirheumatic drugs (DMARDs). Age- and sex-standardized 5-year incidence of THR and TKR was calculated separately in patients with RA diagnosed in each 6-month period between 1995 and 2009.

A total of 17,505 patients with incident RA were identified, 465 and 650 of whom had undergone THR and TKR surgery, respectively. The average incidence of THR and TKR over the biologic-use era was 6.57 per 1000 person-years (PYs) and 8.51 per 1000 PYs, respectively, with projected figures of 5.63 per 1000 PYs and 12.92per 1000 PYs, respectively

The use of NICE guidance was associated with a decrease in the incidence of TKR surgery of –4.41 per 1000 PYs (95% CI, –6.88 to –1.94), which translated into a relative reduction of 34%. In contrast, no significant effect was observed with respect to the incidence of THR surgery.

The researchers concluded that in patients with early RA (<5 years after diagnosis), a clinically meaningful, significant decline in the rates of TKR — but not THR — surgery was linked to the approval of TNFi treatments in England and Wales.

Reference

Hawley S, Cordtz R, Dreyer L, et al. Association between NICE guidance on biologic therapies with rates of hip and knee replacement among rheumatoid arthritis patients in England and Wales: an interrupted time-series analysis [published online September 23, 2017]. Semin Arthritis Rheum. doi:10.1016/j.semarthrit.2017.09.006