Neuropathic pain is difficult to treat. Luckily, we have acupuncture! Acupuncturists leave us in no doubt that their needles are the solution. But are they correct or perhaps victims of wishful thinking?
This review was aimed at determining 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.
Randomized controlled trials were included 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.
A 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.
The authors concluded that there 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.
This review was published in a respected mainstream journal and conducted by a multidisciplinary team with the following titles and affiliations:
- Associate Professor in the College of Pharmacy at the University of Manitoba in Winnipeg.
- Pharmacist in Edmonton, Alta, and Clinical Evidence Expert for the College of Family Physicians of Canada.
- Family physician and Assistant Professor at the University of Alberta.
- Family physician and Associate Professor in the Department of Family Medicine at the University of Alberta.
- Pharmacist, Clinical Evidence Expert Lead for the College of Family Physicians of Canada, and Associate Clinical Professor in the Department of Family Medicine at the University of Alberta.
- Pharmacist in Edmonton and Clinical Evidence Expert for the College of Family Physicians of Canada.
- Pharmacist and Clinical Evidence Expert at the College of Family Physicians of Canada.
- Family physician, Director of Programs and Practice Support at the College of Family Physicians of Canada, and Adjunct Professor in the Department of Family Medicine at the University of Alberta.
- Professor in the Faculty of Pharmaceutical Sciences at the University of British Columbia in Vancouver.
- Pharmacist at the CIUSSS du Nord-de-l’lle-de-Montréal and Clinical Associate Professor in the Faculty of Pharmacy at the University of Montreal in Quebec.
- Care of the elderly physician and Assistant Professor in the Department of Family Medicine at the University of Alberta.
- Family physician and Professor in the Department of Family Medicine at the University of Alberta.
- Assistant Professor in the Department of Family Medicine at Queen’s University in Kingston, Ont.
- Research assistant at the University of Alberta.
- Medical student at the University of Alberta.
- Nurse in Edmonton and Clinical Evidence Expert for the College of Family Physicians of Canada.
As far as I can see, the review is of sound methodology, it minimizes bias, and its conclusions are therefore trustworthy. They suggest that acupuncture is not effective for neuropathic pain.
But how can this be? Do the authors not know about all the positive evidence on acupuncture? A quick search found positive recent reviews of acupuncture for all of the three indications in question:
- Diabetic neuropathy: Acupuncture alone and vitamin B combined with acupuncture are more effective in treating DPN compared to vitamin B.
- Herpes zoster: Acupuncture may be effective for patients with HZ.
- Trigeminal neuralgia: Acupuncture appears more effective than pharmacotherapy or surgery.
How can we explain this obvious contradiction?
Which result should we trust?
Do we believe pro-acupuncture researchers who published their papers in pro-acupuncture journals, or do we believe the findings of researchers who could not care less whether their work proves or disproves the effectiveness of acupuncture?
I think that these papers offer an exemplary opportunity for us to study how powerful the biases of researchers can be. They also remind us that, in the realm of so-called alternative medicine (SCAM), we should always be very cautious and not accept every conclusion that has been published in supposedly peer-reviewed medical journals.