Background Little is known about disease activity at start of biologic therapy and influence on productivity losses.
Objectives To compare work loss in patients with RA starting their first ever biologic therapy with high vs. moderate disease activity.
Methods We identified RA patients aged 20-63 years-old from the Swedish Biologics Register who started their first biologic treatment in 2007-2009 with high (DAS28>5.1; n=830) or moderate (DAS28 3.2-5.1; n=843) disease activity. Lost work days were defined as net sick leave and/or disability pension days, retrieved from the Swedish Social Insurance Agency. Between-group mean differences (at month 12 and per annum the year after treatment start) were estimated by adjusting for age, sex, calendar year, education level, disease duration, comorbidity, and lost work days the month before treatment start.
Results Patients with high vs. moderate disease activity were older (52y vs. 50y; P<0.01), in both groups 77% were women, and mean disease duration was 9y (both P>0.98). During follow-up, patients with high disease activity accumulated 178 annual lost work days compared to 136 in the moderate group (adjusted mean difference, 13; 95%CI 4-21, figure). No between-group difference was detected in patients with no or full-time disability pension at baseline. Among patients with part-time disability pension, those starting treatment at high vs. moderate disease activity had greater work loss.
Conclusions 1-year work loss after starting biologic treatment was substantial in both patients with high and moderate disease activity, with a between-group difference that was largely driven by differences in baseline disability pension status. Although accumulated disease activity over time is a predictor of many outcomes in RA, disease activity at start of biologics was not a strong predictor of subsequent work loss after adjustment.
Acknowledgements The ARTIS Study Group conducts scientific analyses using data from the Swedish biologics register (ARTIS) run by the Swedish Society for Rheumatology. For the maintenance of this register, the Swedish Society for Rheumatology has received funding, independent of the conduct of these scientific analyses, from Merck, BMS, Pfizer, AbbVie, SOBI, UCB, Astra Zeneca and Roche.
This study further received funding from Pfizer and the Swedish Foundation for Strategic Research. These entities had no influence on the data collection, statistical analyses, manuscript preparation, or decision to submit.
Disclosure of Interest None declared
Statistics from Altmetric.com
If you wish to reuse any or all of this article please use the link below which will take you to the Copyright Clearance Center’s RightsLink service. You will be able to get a quick price and instant permission to reuse the content in many different ways.