title: Ultramicronized palmitoylethanolamide in spinal cord injury neuropathic pain: a randomized, double-blind, placebo-controlled trial.
abstract: Neuropathic pain and spasticity after spinal cord injury (SCI) represent significant problems. Palmitoylethanolamide (PEA), a fatty acid amide that is produced in many cells in the body, is thought to potentiate the action of endocannabinoids and to reduce pain and inflammation. This randomized, double-blind, placebo-controlled, parallel multicenter study was performed to investigate the effect of ultramicronized PEA (PEA-um) as add-on therapy on neuropathic pain in individuals with SCI. A pain diary was completed and questionnaires were completed before and after the 12-week treatment with either placebo or PEA-um. The primary outcome measure was the change in mean neuropathic pain intensity from the 1-week baseline period to the last week of treatment measured on a numeric rating scale ranging from 0 to 10. The primary efficacy analysis was the intention to treat (baseline observation carried forward). Secondary outcomes included a per protocol analysis and effects on spasticity, evoked pain, sleep problems, anxiety, depression, and global impression of change. We randomized 73 individuals with neuropathic pain due to SCI, of which 5 had a major protocol violation, and thus 68 were included in the primary analysis. There was no difference in mean pain intensity between PEA-um and placebo treatment (P = 0.46, mean reductions in pain scores 0.4 (-0.1 to 0.9) vs 0.7 (0.2-1.2); difference of means 0.3 (-0.4 to 0.9)). There was also no effect of PEA-um as add-on therapy on spasticity, insomnia, or psychological functioning. PEA was not associated with more adverse effects than placebo.
authors.affiliation: Spinal Cord Injury Centre of Western Denmark, Department of Neurology, Regional Hospital of Viborg, Viborg, Denmark.
authors.forename: Sven R
authors.initials: SR
authors.lastname: Andresen
authors.affiliation: Clinic for Spinal Cord Injuries, Rigshospitalet, University of Copenhagen, Copenhagen, Denmark.
authors.forename: Jette
authors.initials: J
authors.lastname: Bing
authors.affiliation: Spinal Cord Injury Centre of Western Denmark, Department of Neurology, Regional Hospital of Viborg, Viborg, Denmark.
authors.forename: Rikke M
authors.initials: RM
authors.lastname: Hansen
authors.affiliation: Clinic for Spinal Cord Injuries, Rigshospitalet, University of Copenhagen, Copenhagen, Denmark.
authors.forename: Fin
authors.initials: F
authors.lastname: Biering-Sørensen
authors.affiliation: Spinal Cord Injury Centre of Western Denmark, Department of Neurology, Regional Hospital of Viborg, Viborg, Denmark.
authors.forename: Inger L
authors.initials: IL
authors.lastname: Johannesen
authors.affiliation: Spinal Cord Injury Centre of Western Denmark, Department of Neurology, Regional Hospital of Viborg, Viborg, Denmark.|Department of Clinical Medicine, University of Bergen, Bergen, Norway.|The Autonomic Unit, National Hospital for Neurology and Neurosurgery, University College London, Queen Square, United Kingdom.
authors.forename: Ellen Merete
authors.initials: EM
authors.lastname: Hagen
authors.affiliation: Pain Research, Department of Surgery and Cancer, Imperial College, London, United Kingdom.
authors.forename: Andrew S C
authors.initials: ASC
authors.lastname: Rice
authors.affiliation: Hammel Neurorehabilitation and Research Centre, Hammel, Denmark.
authors.forename: Jørgen F
authors.initials: JF
authors.lastname: Nielsen
authors.affiliation: Department of Neurology, Aalborg University Hospital, Aalborg, Denmark.
authors.forename: Flemming W
authors.initials: FW
authors.lastname: Bach
authors.affiliation: Danish Pain Research Center, Department of Clinical Medicine, Aarhus University, Aarhus, Denmark.
authors.forename: Nanna B
authors.initials: NB
authors.lastname: Finnerup
mesh_terms: D000328:Adult; D000368:Aged; D000577:Amides; D000700:Analgesics / Q000627:therapeutic use*; D000704:Analysis of Variance; D004311:Double-Blind Method; D004983:Ethanolamines / Q000627:therapeutic use*; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D008297:Male; D008875:Middle Aged; D009437:Neuralgia / Q000188:drug therapy* / Q000209:etiology*; D010169:Palmitic Acids / Q000627:therapeutic use*; D013119:Spinal Cord Injuries / Q000150:complications*; D016896:Treatment Outcome
chemical_list: D000577:Amides; D000700:Analgesics; D004983:Ethanolamines; D010169:Palmitic Acids; C005958:palmidrol