Perceived work ability, quality of life, and fatigue in patients with rheumatoid arthritis after a 6-month course of TNF inhibitors: prospective intervention study and partial economic evaluation

Abstract

Objective: The objective of this exploratory study was to evaluate the effects and costs of a 6-month course of tumour necrosis factor (TNF) inhibitors on work ability, quality of life, and fatigue in patients with rheumatoid arthritis (RA).

Methods: In this prospective single-arm intervention study 59 consecutive patients of working age with established RA were recruited from an outpatient clinic in Amsterdam, the Netherlands. All patients received fortnightly subcutaneous injections of 40 mg adalimumab. The three outcomes at baseline and 6 months were: perceived work ability [Work Ability Index (WAI)], quality of life [Rheumatoid Arthritis Quality of Life instrument (RAQoL)], and fatigue [Checklist Individual Strength (CIS), Need for Recovery (NFR) scale]. Cost data of the preceding 6 months were collected using a self-administered patient questionnaire at baseline and follow-up.

Results: At 6 months, all outcomes showed a statistically significant improvement in mean scores from baseline, ranging from 10.0% (WAI), to 11.7% (RAQoL), to 15% (NFR) (subgroup paid work, n = 26). The total mean costs showed a twofold increase in mean costs per week per patient [difference EUR 169, 95% confidence interval (CI) EUR 113-226].

Conclusions: In this short-term exploratory evaluation, a 6-month course of TNF inhibitors improved work ability and quality of life, and reduced fatigue in patients with established RA. These effects are associated with an increase in total healthcare costs, attributable to the costs of TNF inhibitors. Randomized controlled trials with a longer follow-up are needed to show a long-term effect on work disability and the potential cost-effectiveness of TNF inhibitors.