Risk and predictors of work disability in Chinese patients with systemic lupus erythematosus

Abstract

The aim of this study is to determine the risk and predictive factors for work disability in patients with SLE. A cross-sectional questionnaire study was performed to evaluate the employment status of a sample of consecutive Chinese patients with SLE. Demographic, socioeconomic data (age, gender, marital status, years of education and household income), employment status, self-reported fatigue score and disease characteristics (SLE duration, organ damage and disease activity) were collected. Work disability was defined by the failure to work due to SLE. The cumulative incidence of work disability since the time of SLE diagnosis was studied by a Kaplan Meier’s plot, and factors predictive of work disability were studied by Cox regression. A total of 147 patients with SLE were studied (mean age = 39.4 ± 11.3 years; 95% women). Among 105 patients who were working at the time of SLE diagnosis, 39 (37%) lost their ability to work as a result of SLE after a mean disease duration of 10.0 ± 6.1 years. Twenty-two (56%) patients lost their work ability within 2 years of diagnosis of SLE. The self-reported reasons for job loss were musculoskeletal pain (87%), skin disease (26%), renal problem (21%), fatigue (85%), memory deterioration (51%), anxiety or depressive symptoms (74%), too frequent sick leave (10%) and long-term hospitalisation (10%). The cumulative risk of work disability was 36% at 5 years after SLE diagnosis. In a Cox regression model, age (HR = 1.06 [1.02–1.11] per year; P = 0.008), self-reported fatigue score (HR = 1.06 [1.01–1.10] per point; P = 0.01) and mean disease activity score in the preceding two years (HR = 1.20 [1.02–1.42] per point; P = 0.03) were independently associated with working disability. In all, 37% of this group of patients with SLE lost their work ability after having the disease for 10 years. More than 50% of these patients developed work disability within the first 2 years of SLE diagnosis. Older age, fatigue and more active disease were independent predictors of work disability.