Prevalence and predictors of reduced work productivity in patients with psoriatic arthritis

Objectives Psoriatic arthritis (PsA) is a unique inflammatory musculoskeletal disorder associated with psoriasis. Although high rates of absenteeism have been associated with PsA, less is known about the impact of the disease on the productivity of patients who remain at work. The aim of this study was to identify factors associated with reduced work productivity, as measured by the Work Limitations Questionnaire (WLQ), among patients with PsA. Methods Patients attending a single Psoriatic Arthritis Clinic were recruited for participation. Employed participants (including homemakers) first completed a Questionnaire for the Assessment of Work-Related Factors (QAWRF). Eligible participants then completed the WLQ. WLQ scores were used as the dependent variable in linear and logistic regression analyses. Independent variables assessed in this study include work characteristics, demographic factors, and clinical measures. Results One hundred and eighty-six eligible patients (60.9% males) returned their assessment forms for analysis. The mean reduction in work productivity due to illness was 4.3%. In univariate linear regression analysis, work productivity was significantly associated with sex, education status, Psoriasis Area and Severity Index (PASI), AJC, ESR, Functional Co-morbidity Index (FCI), and support at work; associations with gender, ESR, FCI, and medications were also significant in a reduced multivariate model. Conclusions Work productivity was associated with demographic, clinical, and work-related factors in PsA. These variables may be useful in identifying patients who require more aggressive intervention, including the use of effective drugs to control disease activity and advocacy for a more supportive work environment.