title: Chronic alcohol self-administration in monkeys shows long-term quantity/frequency categorical stability.
abstract: BACKGROUND
  The current criteria for alcohol use disorders (AUDs) do not include consumption (quantity/frequency) measures of alcohol intake, in part due to the difficulty of these measures in humans. Animal models of ethanol (EtOH) self-administration have been fundamental in advancing our understanding of the neurobiological basis of AUD and can address quantity/frequency measures with accurate measurements over prolonged periods of time. The nonhuman primate model of voluntary oral alcohol self-administration has documented both binge drinking and drinking to dependence and can be used to test the stability of consumption measures over time.
  
  
  METHODS
  Here, an extensive set of alcohol intakes (g/kg/d) was analyzed from a large multi-cohort population of Rhesus (Macaca mulatta) monkeys (n = 31). Daily EtOH intake was uniformly distributed over chronic (12 months) access for all animals.
  
  
  RESULTS
  Underlying this distribution of intakes were subpopulations of monkeys that exhibited distinctive clustering of drinking patterns, allowing us to categorically define very heavy drinking (VHD), heavy drinking (HD), binge drinking (BD), and low drinking (LD). These categories were stable across the 12 months assessed by the protocol, but exhibited fluctuations when examined at shorter intervals.
  
  
  CONCLUSIONS
  The establishment of persistent drinking categories based on quantity/frequency suggests that consumption variables can be used to track long-term changes in behavioral, molecular, or physiochemical mechanisms related to our understanding of diagnosis, prevention, intervention, and treatment efficacies.
authors.affiliation: Department of Computer Science, Baylor University, Waco, Texas.
authors.forename: Erich J
authors.initials: EJ
authors.lastname: Baker
authors.forename: Jonathan
authors.initials: J
authors.lastname: Farro
authors.forename: Steven
authors.initials: S
authors.lastname: Gonzales
authors.forename: Christa
authors.initials: C
authors.lastname: Helms
authors.forename: Kathleen A
authors.initials: KA
authors.lastname: Grant
mesh_terms: D000428:Alcohol Drinking / Q000523:psychology* / Q000639:trends*; D000818:Animals; D015331:Cohort Studies; D000431:Ethanol / Q000008:administration & dosage*; D000882:Haplorhini; D008253:Macaca mulatta; D008297:Male; D012646:Self Administration; D013997:Time Factors
chemical_list: D000431:Ethanol
keywords: Alcohol; Binge Drinking; EtOH; Nonhuman Primates; Self-Administration