Pharmacologic therapies of pain in patients with spinal cord injury: a systematic review

Abstract

Study design: Systematic review. Objectives: This systematic review evaluates all randomized clinical trials (RCTs) conducted on assessing the efficacy and safety of pharmacologic therapies for the treatment of Spinal Cord Injury (SCI)-associated pain. Methods: The PubMed/Medline, EMBASE, and Cochrane library online databases were searched from 1946 to May 2019 using specific search terms for SCI, pain, and RCTs meeting predetermined inclusion criteria. The efficacy outcome of interest was pain reduction, discontinuations, and adverse events (AEs). Results: Of 2746 records identified through database searching, 703 duplicates were deleted. 1814 were excluded, the full text of the remaining 230 articles was reviewed, and finally, 28 papers were selected for drafting. The most studied medications were pregabalin, gabapentin, amitriptyline, and ketamine. Pregabalin, gabapentin, and amitriptyline reduced VAS by more than 30%, and ketamine reduced VAS by 40%. Oxcarbazepine, lamotrigine, alfentanil, tramadol, and morphine added to clonidine, baclofen, and botulinum toxin type A (BTA) significantly reduced pain compared with placebo. On the other hand, valproate, levetiracetam, trazodone, and duloxetine did not significantly alleviate SCI-associated pain compared to placebo. The risks of AEs and discontinuations in anticonvulsants were the least, while it was highest in analgesics. Conclusions: Studies of SCI-associated pain were few, small, heterogenic in measures and values, and did not allow quantitative comparisons of efficacy. However, available data suggested pregabalin and gabapentin led to a more marked reduction in SCI-associated pain with fewer AEs. Additional clinical studies are needed to assess the effect of established and novel management options.