title: Long-Term Outcome of the Management of Chronic Neuropathic Pain: A Prospective Observational Study.
abstract: This prospective observational cohort study addressed the long-term clinical effectiveness of the management of chronic neuropathic noncancer pain at 7 Canadian tertiary pain centers. Patients were treated according to standard guidelines and were followed at 3, 6, 12, 18, and 24 months. Standard outcome measures for pain, mood, quality of life, and overall treatment satisfaction were administered, with the primary outcome measure designated as the composite of 30% reduction in average pain intensity and 1-point decrease in the mean Interference Scale Score (0-10) of the Brief Pain Inventory at 12 months relative to baseline. Of 789 patients recruited, mean age was 53.5 ± 14.2 years (55% female) and mean duration of pain was 4.88 ± 5.82 years. Mean average pain intensity (0-10) at baseline was 6.1 ± 1.9. All standard outcome measures showed statistically significant improvement at 12 months relative to baseline (P < .001). However, only 23.7% attained clinically significant improvement in pain and function at 12 months as the primary outcome measure. Univariable analyses showed poorer outcomes at 12-month follow-up with longer duration of pain (P = .002), greater cigarette use (P = .01), more disability compensation (P = .001), and higher opioid doses at baseline and at 12 months (P < .02). Our present treatment modalities provide significant long-term benefit in only about a quarter of patients with neuropathic pain managed at tertiary care pain clinics. Opioid therapy may not be beneficial for the long term. Perspective: Evidence-based treatment of chronic neuropathic pain provides long-term benefit in only about one-quarter of patients seen in tertiary care centers. Opioid therapy may not be beneficial.
authors.affiliation: Department of Clinical Neurological Sciences, Western University, London, Ontario, Canada. Electronic address: dwight.moulin@lhsc.on.ca.
authors.forename: Dwight E
authors.initials: DE
authors.lastname: Moulin
authors.affiliation: Department of Anesthesiology, Dalhousie University, Halifax, Nova Scotia, Canada; Department of Psychiatry, Dalhousie University, Halifax, Nova Scotia, Canada.
authors.forename: A John
authors.initials: AJ
authors.lastname: Clark
authors.affiliation: Wasser Pain Management Centre, University of Toronto, Toronto, Ontario, Canada.
authors.forename: Allan
authors.initials: A
authors.lastname: Gordon
authors.affiliation: Department of Anesthesiology, Dalhousie University, Halifax, Nova Scotia, Canada; Department of Psychiatry, Dalhousie University, Halifax, Nova Scotia, Canada.
authors.forename: Mary
authors.initials: M
authors.lastname: Lynch
authors.affiliation: Department of Anesthesia & Perioperative Medicine, Western University, London, Ontario, Canada.
authors.forename: Patricia K
authors.initials: PK
authors.lastname: Morley-Forster
authors.affiliation: Department of Anesthesiology, University of Ottawa, Ottawa, Ontario, Canada.
authors.forename: Howard
authors.initials: H
authors.lastname: Nathan
authors.affiliation: Department of Anesthesiology, University of Ottawa, Ottawa, Ontario, Canada.
authors.forename: Cathy
authors.initials: C
authors.lastname: Smyth
authors.affiliation: Department of Clinical Neurological Sciences, University of Calgary, Calgary, Alberta, Canada.
authors.forename: Cory
authors.initials: C
authors.lastname: Toth
authors.affiliation: School of Nursing & Department of Anesthesiology & Perioperative Medicine, Queens University, Kingston, Ontario, Canada.
authors.forename: Elizabeth
authors.initials: E
authors.lastname: VanDenKerkhof
authors.affiliation: Department of Internal Medicine, McMaster University, Hamilton, Ontario, Canada.
authors.forename: Ammar
authors.initials: A
authors.lastname: Gilani
authors.affiliation: Department of Family Medicine, McGill University, Montreal, Quebec, Canada.
authors.forename: Mark A
authors.initials: MA
authors.lastname: Ware
mesh_terms: D000328:Adult; D000368:Aged; D000701:Analgesics, Opioid / Q000008:administration & dosage*; D002170:Canada; D016009:Chi-Square Distribution; D002908:Chronic Disease; D005260:Female; D006801:Humans; D008137:Longitudinal Studies; D008297:Male; D008875:Middle Aged; D009437:Neuralgia / Q000453:epidemiology* / Q000628:therapy*; D010147:Pain Measurement; D011446:Prospective Studies; D016896:Treatment Outcome
chemical_list: D000701:Analgesics, Opioid
keywords: Prospective cohort study; chronic neuropathic pain; long-term outcome; opioid treatment