PEER systematic review of randomized controlled trials: Management of chronic neuropathic pain in primary care

ObjectiveTo determine the proportion of patients with neuropathic pain who achieve a clinically meaningful improvement in their pain with the use of different pharmacologic and nonpharmacologic treatments.Data sourcesMEDLINE, EMBASE, the Cochrane Library, and a gray literature search.Study selectionRandomized controlled trials that reported a responder analysis of adults with neuropathic pain—specifically diabetic neuropathy, postherpetic neuralgia, or trigeminal neuralgia—treated with any of the following 8 treatments: exercise, acupuncture, serotonin-norepinephrine reuptake inhibitors (SNRIs), tricyclic antidepressants (TCAs), topical rubefacients, opioids, anticonvulsant medications, and topical lidocaine.SynthesisA total of 67 randomized controlled trials were included. There was moderate certainty of evidence that anticonvulsant medications (risk ratio of 1.54; 95% CI 1.45 to 1.63; number needed to treat [NNT] of 7) and SNRIs (risk ratio of 1.45; 95% CI 1.33 to 1.59; NNT = 7) might provide a clinically meaningful benefit to patients with neuropathic pain. There was low certainty of evidence for a clinically meaningful benefit for rubefacients (ie, capsaicin; NNT = 7) and opioids (NNT = 8), and very low certainty of evidence for TCAs. Very low-quality evidence demonstrated that acupuncture was ineffective. All drug classes, except TCAs, had a greater likelihood of deriving a clinically meaningful benefit than having withdrawals due to adverse events (number needed to harm between 12 and 15). No trials met the inclusion criteria for exercise or lidocaine, nor were any trials identified for trigeminal neuralgia.ConclusionThere is moderate certainty of evidence that anticonvulsant medications and SNRIs provide a clinically meaningful reduction in pain in those with neuropathic pain, with lower certainty of evidence for rubefacients and opioids, and very low certainty of evidence for TCAs. Owing to low-quality evidence for many interventions, future high-quality trials that report responder analyses will be important to strengthen understanding of the relative benefits and harms of treatments in patients with neuropathic pain.