title: Alcohol hangover as a cause of impairment in apprehended drivers.
abstract: OBJECTIVE
  Previous studies have already shown the possibility of impairment during a hangover phase, after alcohol ingestion, when the blood alcohol concentration has returned to zero. The prevalence of drivers being in a hangover phase, in the driving population, and the relation to impairment relevant for traffic safety has, however, not been previously studied. The aim of this study was to investigate the prevalence and the concentrations of the 2 ethanol metabolites, ethyl glucuronide (EtG) and ethyl sulfate (EtS), in blood, indicating very recent alcohol intake, among apprehended drivers, in which no psychoactive substances, including alcohol, were detected. The aim was also to study these findings in relation to the impairment observed in these drivers.
  
  
  METHODS
  Blood samples, drawn from suspected drunk or drugged drivers, were analyzed for a broad repertoire of psychoactive substances, with a clinical test for impairment (CTI) being performed at the same time. One hundred and forty-six cases, in which no psychoactive substances were detected and where a valid CTI was performed, were analyzed for EtG and EtS in blood. The prevalence and concentrations were related to the conclusions of the CTIs.
  
  
  RESULTS
  EtS and EtG were detected in a total of 19 of the 146 cases (13%). Among the "impaired" drivers, EtG and EtS were detected in 16 cases (18%), whereas among "not impaired" drivers they were detected in 3 cases (5%). There were significantly more detections of EtS (and EtG) among the impaired group of drivers compared to the nonimpaired drivers (P =.030), and the concentrations of both EtG (P =.027) and EtS (P =.026) were significantly higher in the group of impaired drivers compared to the nonimpaired drivers. There was a statistically significant positive correlation between the concentrations of EtG (Spearman's rho = 0.170, P =.041) and EtS (Spearman's rho = 0.189, P =.022) and the degree of impairment.
  
  
  CONCLUSIONS
  EtG and EtS were prevalent findings in blood collected from the apprehended drivers, testing negative for all psychoactive substances. The higher rates of detections of EtG and EtS in impaired compared to nonimpaired drivers, and also the positive correlation between concentrations of EtG and EtS and the degree of impairment, indicate that hangover symptoms may be relevant for traffic safety.
authors.affiliation: a Norwegian Institute of Public Health , Division of Forensic Sciences , Oslo , Norway.
authors.forename: Gudrun
authors.initials: G
authors.lastname: Høiseth
authors.forename: Jan Toralf
authors.initials: JT
authors.lastname: Fosen
authors.forename: Veronica
authors.initials: V
authors.lastname: Liane
authors.forename: Stig Tore
authors.initials: ST
authors.lastname: Bogstrand
authors.forename: Jørg
authors.initials: J
authors.lastname: Mørland
mesh_terms: D000435:Alcoholic Intoxication / Q000097:blood / Q000453:epidemiology / Q000523:psychology*; D001334:Automobile Driving / Q000331:legislation & jurisprudence / Q000523:psychology*; D016208:Databases, Factual; D005965:Glucuronates / Q000097:blood*; D006801:Humans; D009664:Norway / Q000453:epidemiology; D013463:Sulfuric Acid Esters / Q000097:blood*
chemical_list: D005965:Glucuronates; D013463:Sulfuric Acid Esters; C093924:ethyl glucuronide; C011612:diethyl sulfate
keywords: DUI; alcohol; blood alcohol; impairment