N-of-1 Randomized Trials to Assess the Efficacy of Gabapentin for Chronic Neuropathic Pain

Yelland, Michael J., Poulos, Christopher J., Pillans, Peter I., Bashford, Guy M., Nikles, Catherine Jane, Sturtevant, Joanna M., Vine, Norma, Del Mar, Christopher, Schluter, Philip J., Tan, Meng, Chan, Jonathon, Mackenzie, Fraser and Brown, Robyn (2009) N-of-1 Randomized Trials to Assess the Efficacy of Gabapentin for Chronic Neuropathic Pain. Pain Medicine, 10 4: 754-761. doi:10.1111/j.1526-4637.2009.00615.x

Author Yelland, Michael J.
Poulos, Christopher J.
Pillans, Peter I.
Bashford, Guy M.
Nikles, Catherine Jane
Sturtevant, Joanna M.
Vine, Norma
Del Mar, Christopher
Schluter, Philip J.
Tan, Meng
Chan, Jonathon
Mackenzie, Fraser
Brown, Robyn
Title N-of-1 Randomized Trials to Assess the Efficacy of Gabapentin for Chronic Neuropathic Pain
Formatted title
N-of-1 Randomized Trials to Assess the Efficacy of Gabapentin for Chronic Neuropathic Pain
Journal name Pain Medicine   Check publisher's open access policy
ISSN 1526-2375
Publication date 2009-05-01
Year available 2009
Sub-type Article (original research)
DOI 10.1111/j.1526-4637.2009.00615.x
Volume 10
Issue 4
Start page 754
End page 761
Total pages 8
Place of publication United States
Publisher Wiley-Blackwell Publishing Inc
Collection year 2010
Language eng
Subject C1
111717 Primary Health Care
920199 Clinical Health (Organs, Diseases and Abnormal Conditions) not elsewhere classified
Formatted abstract
Objective. The objective of this study was to compare the efficacy of gabapentin with placebo for neuropathic pain at the individual and population levels.

Design. This study used an n-of-1 trial methodology with three double-blind, randomized, crossover comparisons of gabapentin with placebo.

Setting. This study was carried out at specialist outpatient clinics at two Australian hospitals.

Patients. The patients are adults with chronic neuropathic pain.

Interventions. Following a dose-finding period, participants underwent three comparisons of 2-week periods on gabapentin (600–1,800 mg per day) and placebo. The dose-finding period was commenced by 112 patients, of whom 39 had no response so they did not enroll, leaving 73 trial participants. Of these, 48 completed and 7 partially completed their trials, and 18 withdrew.
Outcome Measures. The five outcome measures were the visual analog scale (0–10) of pain, sleep interference and functional limitation; frequency of adverse events and medication preference. The aggregate response was determined by weighting the response to each measure equally.

Results. Of the 55 participants who completed at least one cycle, the aggregate response to gabapentin was better than placebo in 16 (29%), of whom 15 continued gabapentin posttrial. No difference was shown in 38 (69%), and 1 (2%) showed a better response to placebo. Fifteen of these
39 continued gabapentin posttrial. Meta-analysis of the mean scores showed lower mean (standard deviation) scores for gabapentin by 0.8 (0.2) for pain, 0.6 (0.2) for sleep interference, and 0.6 (0.2) for functional limitation.

Conclusions. The response rate and mean reduction in symptoms with gabapentin were small. Gabapentin prescribing posttrial was significantly influenced by the trial results.
Keyword randomised controlled trial
crossover trails
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Q-Index Code C1
Q-Index Status Confirmed Code

Document type: Journal Article
Sub-type: Article (original research)
Collections: 2010 Higher Education Research Data Collection
School of Nursing, Midwifery and Social Work Publications
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Citation counts: TR Web of Science Citation Count  Cited 16 times in Thomson Reuters Web of Science Article | Citations
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Created: Wed, 26 Aug 2009, 21:03:01 EST by Vicki Percival on behalf of School of Nursing, Midwifery and Social Work