Perioperative pregabalin administration does not prevent chronic postoperative pain: systematic review with a meta-analysis of randomized trials

The efficacy of perioperative pregabalin treatment for preventing chronic pain remains a matter of debate. We searched the MEDLINE, EMBASE, LILACS, Cochrane, and Clinical Trial Register databases, and other sources, for randomized controlled trials comparing the effects of pregabalin and placebo. The primary outcome was the incidence of chronic postsurgical pain (CPSP) at 3 months. The secondary endpoints were CPSP at 3, 6, and 12 months and the incidence of chronic postsurgical neuropathic pain at the same time points. A random-effect meta-analysis was performed on the combined data. Evidence quality was rated by the GRADE method. We included 18 studies (2485 patients) in the meta-analysis. Overall, 60% of the trials reporting the primary outcome at 3 months were unpublished; the unpublished trials corresponded to 1492/1884 (79%) of the patients included in these studies. No difference in CPSP incidence between pregabalin and placebo was found at any time point; the risk ratio was 0.87 (0.66, 1.14), I-2 557% at 3 months. The evidence was considered to be of moderate quality. Subgroup analysis by publication status, daily dose, type of administration, and type of surgery did not highlight any differences between subgroups. Insufficient data concerning the incidence of chronic postsurgical neuropathic pain were available for any firm recommendation to be made. Pooled data from published and unpublished studies provide no support for the efficacy of pregabalin for preventing CPSP.