title: Characteristics of methadone-related fatalities in Norway.
abstract: There are currently over 7000 patients enrolled in opioid maintenance treatment (OMT) programs in Norway. A rise in methadone-related deaths proportional to increasing methadone sales over the period 2000-2006 has been observed, but the causative factors for these fatalities have been elusive. In the present study, individual characteristics, methadone concentrations and additional toxicological findings were analyzed. Methadone intoxication deaths (n = 264) were divided into 3 groups according to toxicological findings in whole blood: group 1 - methadone detected alone, or together with one additional drug at low or therapeutic levels, or a low concentration of ethanol (<1 g/L) (n = 21); group 2 - multiple additional drugs/substances detected below lethal levels (n = 175); group 3 - one or more additional drugs/substances detected at lethal levels, or ethanol >3 g/L (n = 55). Methadone blood concentrations in decedents who had been enrolled in OMT were higher than for decedents not in treatment, in all groups. Blood methadone concentrations around 1 mg/L were present in fatal multi-drug intoxications in OMT patients. Results suggest that some patients may be at risk of dying when combining therapeutic concentrations of methadone with other psychoactive substances. Somatic disease was a common finding among deceased OMT patients. Concentrations in methadone users not enrolled in OMT were predominantly between 0.3 and 0.4 mg/L and were not related to the presence of other drugs. However, methadone concentrations below 0.1 mg/L may be associated with intoxication following methadone use, both alone and in combination with other drugs. Younger male users (mean age 34 years) seemed to have a higher susceptibility to methadone intoxication.
authors.affiliation: Norwegian Institute of Public Health, Division of Forensic Sciences, Oslo, Norway; Centre for Psychopharmacology, Diakonhjemmet Hospital, Oslo, Norway. Electronic address: jpbern28@hotmail.com.
authors.forename: Jean-Paul
authors.initials: JP
authors.lastname: Bernard
authors.affiliation: Norwegian Institute of Public Health, Division of Forensic Sciences, Oslo, Norway; Oslo University Hospital, Rikshospitalet, Department of Pharmacology, Oslo, Norway.
authors.forename: Hassan Z
authors.initials: HZ
authors.lastname: Khiabani
authors.affiliation: Norwegian Institute of Public Health, Division of Forensic Sciences, Oslo, Norway; Fürst Medical Laboratory, Oslo, Norway.
authors.forename: Thor
authors.initials: T
authors.lastname: Hilberg
authors.affiliation: Norwegian Institute of Public Health, Division of Forensic Sciences, Oslo, Norway.
authors.forename: Ritva
authors.initials: R
authors.lastname: Karinen
authors.affiliation: Department of Laboratory Medicine, Children's and Women's Health, Norwegian University of Science and Technology, Trondheim, Norway; Department of Clinical Pharmacology, St. Olav's Hospital, Trondheim, Norway.
authors.forename: Lars
authors.initials: L
authors.lastname: Slørdal
authors.affiliation: SERAF-Norwegian Centre for Addiction Research, University of Oslo, Oslo, Norway; Oslo University Hospital, Division of Mental Health and Addiction, Oslo, Norway.
authors.forename: Helge
authors.initials: H
authors.lastname: Waal
authors.affiliation: Norwegian Institute of Public Health, Division of Forensic Sciences, Oslo, Norway; Institute of Clinical Medicine, University of Oslo, Norway.
authors.forename: Jørg
authors.initials: J
authors.lastname: Mørland
mesh_terms: D000328:Adult; D002492:Central Nervous System Depressants / Q000097:blood; D015897:Comorbidity; D000431:Ethanol / Q000097:blood; D005260:Female; D053593:Forensic Toxicology; D006801:Humans; D008297:Male; D008691:Methadone / Q000097:blood / Q000506:poisoning*; D008875:Middle Aged; D009294:Narcotics / Q000097:blood / Q000506:poisoning*; D009664:Norway / Q000453:epidemiology; D058850:Opiate Substitution Treatment; D011619:Psychotropic Drugs / Q000009:adverse effects / Q000097:blood; D019966:Substance-Related Disorders / Q000097:blood / Q000401:mortality
chemical_list: D002492:Central Nervous System Depressants; D009294:Narcotics; D011619:Psychotropic Drugs; D000431:Ethanol; D008691:Methadone
keywords: Deaths; Methadone; OMT; Opioids; Toxicity