PROGNOSTIC FACTORS FOR RETURN TO WORK AFTER A FIRST COMPENSATED EPISODE OF BACK PAIN

Objectives-To determine which factors measured at baseline and during the course of treatment influence time to return to work after a first compensated episode of back pain. Methods-The design is a treatment i nception cohort including 305 compensated workers out of 402 eligible ones presenting at two rehabilitation centres for conventional treatme nt. Crude and adjusted rate ratios (RRs) along with 95% confidence int ervals (95% CIs) were estimated with the Cox's proportional hazards re gression. Results-50% of workers had not returned to work after 112 da ys of follow up, and 11.3% still had not after 270 days. At the end of the study period (maximum follow up time was 1228 days), 230 workers (75.4%) had returned to work, 6.5% had not, and a similar percentage h ad retired, gone into vocational training, or returned to school. In t he final model stratified for radiating pain during treatment, which w as an important prognostic variable, workers between 21 to 30 years of age had a greater chance of returning to work (RR (95% CI) 1.43 (1.03 to 1.98)) than those greater than or equal to 30. The other factors a ssociated with a greater chance of returning to work were: a diagnosis of sprain or pain v a diagnosis of intervertebral disc disorder (2.20 (1.233.91)), < 30 days of waiting between the accident and the beginn ing of treatment (1.30 (0.96 to 1.77)), a good flexion at baseline (1. 52 (1.01 to 2.23)), absence of neurological symptoms during treatment (1.40 (0.98-2.00)), > 24 months of employment in the industry (1.49 (1 .10 to 2.03)), working for a public industry v a private one (1.63 (1. 21 to 2.19)), and the ability to take unscheduled breaks (1.45 (1.06 t o 1.97)). Conclusions-Even with a first-episode of back pain, time to return to work is long and the proportion not returning is high. Retur n to work as expected is influenced by disease and host characteristic s but: also by social and work factors. Reinstatement programmes shoul d account for all these factors.