POS0236 COMPARISON OF WORK PRODUCTIVITY OUTCOMES BETWEEN CHRONIC BACK PAIN PATIENTS WITH AND WITHOUT A DIAGNOSIS OF AXIAL SPONDYLOARTHRITIS AFTER 2-YEAR PROTOCOLISED FOLLOW-UP: DATA FROM THE SPONDYLOARTHRITIS CAUGHT EARLY COHORT
Authors: A. Boel, M. Van Lunteren, K. M. Fagerli, R. Ramonda, S. Exarchou, M. Van de Sande, F. A. Van Gaalen, D. Van der Heijde
Journal: Annals of the Rheumatic Diseases (2021)

Background: Objectives: To compare work-productivity and activity impairment outcomes between chronic back pain (CBP) patients with and without an axSpA diagnosis after two years of protocollised follow-up. Methods: Work productivity was assessed using the Work Productivity and Activity Impairment (WPAI) general health version 1.0 questionnaire. Presenteeism was defined as a reduction in performance due to disease while at work; absenteeism was time missed from work due to disease; work productivity loss (WPL) was a combined measure of presenteeism and absenteeism; and activity impairment was impairment due to disease in all non-work related activities. All WPAI outcomes were presented as percentages; higher scores implying greater impairment. Additionally, the proportion of patients with any (&gt;0%) absenteeism, presenteeism, WPL and activity impairment were given. This study used data from the SPACE cohort, which consists of patients with CBP (≥ 3 months &lt;2 years) suspected of axSpA. Analyses were restricted to patients with a diagnosis axSpA or no axSpA (CBP group) with a level of confidence ≥7 (on a 0-10 scale) after locally read imaging. Additionally, data had to be available on the WPAI questionnaire at both timepoints. Assessment of presenteeism, absenteeism and WPL was restricted to the working population, defined as having paid work at baseline and 2-year follow-up. Activity impairment was assessed for the entire study population. Regression models were used to test the difference between groups at two-year follow-up for all WPAI variables. Baseline WPAI values and NSAID-use over time were tested as confounders. Results: Patients with a diagnosis of axSpA were more frequently male (56% vs 30%) and HLA-B27 positive (73% vs 31%) and had more SpA features at baseline compared to the patients with CBP [mean (SD) 5(2) vs 3(1)]. Age, symptom duration, NSAID-use and the percentage of patients with paid work at baseline were similar between groups. The population having paid work at baseline and 2 years consisted of 124 patients (69%) in the axSpA group and 52 patients (70%) in the CBP group. In both groups the proportion of patients with any as well as the mean WPL reduces. This reduction was apparent in both presenteeism and absenteeism. Nevertheless, presenteeism, WPL and activity impairment were significantly higher at two-year follow-up in the group with CBP (Table 1). In these regression models with baseline values and NSAID-use over time as covariates, axSpA was an independent predictor of lower presenteeism, WPL and activity impairment at two-year follow-up. Table 1. Work-productivity outcomes at baseline and two-year follow-up for the group with a diagnosis of axSpA and the group without a diagnosis. Diagnosis axSpA Baseline 2 years CBP Baseline 2 years p-values between groups at 2yrs Working population N=124 N=52 Presenteeism, mean (SD) % 31 (28) 18 (24) † 40 (29) 30 (30) † p=0.003* Presenteeism present, % 73 52 87 67 Absenteeism, mean (SD) % 7 (18) 4 (14) † 12 (25) 6 (21) † p=0.334 Absenteeism present, % 22 7 27 12 Overall work impairment, mean (SD) % 33 (29) 22 (27) † 43 (30) 35 (33) p=0.005* Overall work impairment present, % 72 46 87 65 Total population N=181 N=74 Activity impairment, mean (SD) % 38 (28) 22 (24) † 50 (29) 33 (29) † p=0.001* Activity impairment, n(%) 86 64 93 70 * Significant difference between groups at two years; after correction for baseline values and NSAID use over time † Significant improvement within group over time Conclusion: Despite significant improvements in both groups, patients with axSpA have significantly better work-related outcomes after two years of protocolised follow-up compared to those without axSpA. Disclosure of Interests: None declared