Catastrophizing moderates the effect of exposure in vivo for back pain patients with pain-related fear

Abstract

This investigation was an initial attempt to explore psychological factors that might help or hinder the effect of exposure in vivo for patients with musculoskeletal pain and pain-related fear. The study was based on data from a randomized-controlled trial for patients with non-specific spinal pain (Linton et al., 2008). First, catastrophizing, anxiety, and depression were studied as possible treatment moderators. We found evidence that catastrophizing was a moderator of treatment outcome in exposure. When further exploring the nature of the relationship between catastrophizing and outcome, the results showed that the exposure was effective only for patients with low or moderate levels of catastrophizing. High catastrophizers did not improve from the treatment. On the other hand, anxiety was a general predictor of poor outcome, and not a specific moderator of outcome in exposure. In contrast, depression was not significantly related to outcome. Next, patients were divided into high change participants and low change participants based on their improvement in disability after treatment in order to investigate the change in psychological variables during treatment. Descriptive data indicated that high change participants had large improvements across treatment on depression, anxiety, catastrophizing, and fear-avoidance beliefs whereas low change participants virtually did not change at all on these variables across treatment. These findings denote that catastrophizing is a moderator of treatment outcome in exposure whereas several psychological variables might be important for the treatment process.