Outcomes of pain center treatment in Washington State workers' compensation.

Abstract

Injured workers with chronic pain who have failed conventional therapies often receive treatment at pain centers. This study evaluated the effect of pain center treatment on time loss status of Washington State injured workers. The primary hypothesis was that treatment at a pain center would lead to a reduction in the probability of a worker's receiving time loss benefits at a 2-year follow-up. A population-based retrospective cohort study was performed on 2,032 Washington State workers' compensation patients who underwent pain center evaluations. Subjects who received pain center treatment were compared to those who were evaluated but not treated with respect to time loss status at 2-year follow-up. Univariate analysis revealed that at 2-year follow-up, 35% of treated subjects were receiving time loss payments vs. 40% of evaluated only subjects (P < 0.05). Subjects who were younger, female, and less chronic were more likely to undergo pain center treatment and were less likely to be on time loss at 2-year follow-up. In multivariate analyses, which statistically controlled baseline differences between the two groups, there was no difference between treated subjects and evaluated only subjects. There was no evidence that pain center treatment alters 2-year time loss status of already disabled workers.