Study design: Systematic review.
Objective: The aim of this study was to assess the effect of catastrophizing on treatment efficacy and outcome in patients treated for low back pain.
Summary of background data: Psychological factors including catastrophizing thoughts are thought to increase the risk for chronic low back pain. The influence of catastrophizing is debated.
Methods: In September 2012, the following databases were searched: BIOSIS, CINAHL, Cochrane Library, EMBASE, OTseeker, PeDRO, PsycINFO, MEDLINE, Scopus, and Web of Science. For 50 of 706 references, full text was assessed. Results based on 11 studies were included in this analysis.
Results: In the 11 studies, a total of 2269 patients were included. Seven studies were of good and 4 of moderate methodological quality. Heterogeneity in study settings, treatments, outcomes, and patient populations impeded meta-analysis. Catastrophizing at baseline was predictive for disability at follow-up in 4 studies and for pain in 2 studies. Three studies found no predictive effect of catastrophizing. A mediating effect was found in all studies (n = 5) assessing the impact of a decrease in catastrophizing during treatment. A greater decrease was associated with better outcome. Most studies that investigated the moderating effects on treatment efficacy found no effect (n = 5). However, most studies did not look for a direct interaction between the treatment and catastrophizing thoughts. No study investigated the influence of catastrophizing on work-related outcomes including return to work.
Conclusion: Catastrophizing predicted degree of pain and disability and mediated treatment efficacy in most studies. The presence of catastrophizing should be considered in patients with persisting back pain. Limited evidence was found for the moderating effects on treatment efficacy. Future research should aim to clarify the role of catastrophizing as a moderator of outcome and investigate its importance for work-related outcomes.
Level of evidence: 1.