title: Heroin-using drivers: importance of morphine and morphine-6-glucuronide on late clinical impairment.
abstract: OBJECTIVE
  To evaluate the relationship between major heroin metabolites (morphine, morphine-6-glucoronide), pattern of drug use, and late impairment of psychomotor functions.
  
  
  METHODS
  From the database of the Norwegian Institute of Public Health, Oslo, blood morphine concentration in samples from heroin users (n=70) containing only morphine were correlated with results of the clinical test for impairment (CTI). For comparison, test results were explored in individuals without any positive analytical finding in blood samples (n=79) selected from the same database.
  
  
  RESULTS
  In the "no drug" cases, 86% were judged as not impaired and 14% as impaired. In the morphine only cases, 20% were judged as not impaired, and 80% as impaired. Both daily users and non-daily users had the same proportion of impaired cases. Median blood morphine concentration (M) was 0.09 micromol/l in the "not impaired" group and 0.15 micromol/l in the "impaired" group (P=0.067). For morphine-6-glucuronide (M6G), the median blood concentration was 0.09 micromol/l in the "not impaired" group and 0.14 micromol/l in the "impaired" group (P=0.030). A significant correlation between concentration quartiles and number of cases determined as "impaired" was found for M6G (P=0.018) and for the sum M+M6G (P=0.013).
  
  
  CONCLUSIONS
  In our population of heroin-drugged drivers, blood concentrations of M6G and the sum M+M6G appeared to have concentration-dependent effects on the CNS that may lead to impairment as judged from a CTI. Variations in pattern of use did not seem to have any bearing on the judgement of impairment.
authors.affiliation: Division for Forensic Toxicology and Drug Abuse, Norwegian Institute of Public Health, P.O. Box 4404, Nydalen, 0403, Oslo, Norway. liba@fhi.no
authors.forename: Liliana
authors.initials: L
authors.lastname: Bachs
authors.forename: Gudrun
authors.initials: G
authors.lastname: Høiseth
authors.forename: Svetlana
authors.initials: S
authors.lastname: Skurtveit
authors.forename: Jørg
authors.initials: J
authors.lastname: Mørland
mesh_terms: D000328:Adult; D001334:Automobile Driving; D003071:Cognition; D005260:Female; D006556:Heroin Dependence / Q000378:metabolism*; D006801:Humans; D008297:Male; D008875:Middle Aged; D009020:Morphine / Q000032:analysis*; D009022:Morphine Derivatives / Q000032:analysis*; D009294:Narcotics / Q000032:analysis*; D011597:Psychomotor Performance; D012189:Retrospective Studies; D015813:Substance Abuse Detection / Q000379:methods*; D013997:Time Factors
chemical_list: D009022:Morphine Derivatives; D009294:Narcotics; C035349:morphine-6-glucuronide; D009020:Morphine; C018108:morphine-3-glucuronide