Objective: To investigate the efficacy of anticonvulsants or antidepressants in combination pharmacotherapy for treatment of neuropathic pain in cancer patients.
Materials and methods: We systematically searched the Cochrane Central Register of Controlled Trials, MEDLINE, EMBASE, and the metaRegister of Controlled Trials for randomized controlled trials that compared anticonvulsants or antidepressants in combination pharmacotherapy (experimental group) with treatments without anticonvulsants or antidepressants (control group) for neuropathic pain in cancer patients. Risk of bias was evaluated in accordance with the Cochrane Handbook for Systematic Reviews of Interventions. The primary outcome was a mean difference (MD) in change in global pain analyzed by a random-effects model.
Results: Eight trials met the inclusion criteria with a total of 1359 participants of whom 698 received an experimental intervention. The MD in change in global pain suggested a favorable association with anticonvulsants or antidepressants in combination pharmacotherapy compared with control groups (MD, -0.41; 95% confidence interval, -0.70 to -0.12) with no heterogeneity across trials (I=0%). The MD in change estimated in all sensitivity analyses ranged from -0.36 to -0.47, suggesting that these effects were consistent across different study designs and statistical assumptions.
Conclusions: Anticonvulsants or antidepressants in combination pharmacotherapy reduce neuropathic pain in cancer patients compared with treatments without anticonvulsants or antidepressants. Limited evidence precludes a recommendation on specific adjuvants in combination pharmacotherapy.