title: Predictors of change in cocaine use in a street-recruited cohort of young cocaine users.
abstract: OBJECTIVE
  To determine predictors of changes in amount of cocaine use among regular users outside treatment services.
  
  
  METHODS
  Longitudinal study-we estimated the proportion of subjects who increased or decreased cocaine use and assessed possible predictors related to these changes among a street-recruited cohort of young regular cocaine users (RCU).
  
  
  METHODS
  Three Spanish cities: Barcelona, Madrid and Seville
  
  
  METHODS
  A total of 720 RCU aged 18-30 years not regularly using heroin were recruited in the community during 2004-06 (Itinere Project). Follow-up interviews (n = 501) were carried out at 12-24 months.
  
  
  METHODS
  The average amount of cocaine used weekly was calculated taking into account the number of days of use and the usual quantity (g/day). A multinomial logistic regression approach was used to investigate the association between changes in amount of cocaine use (i.e. difference exceeded 33.3% of baseline level) after 12-24 months, and baseline socio-demographic characteristics, nightlife, patterns of cocaine use and use of alcohol and other psychoactive drugs.
  
  
  RESULTS
  Cocaine use baseline average level was 2.14 g/week [95% confidence interval (CI) = 2.02-2.42]. It decreased in 71.5% of subjects and increased in 14.1%. In multinomial analysis, negative associations were found between decreasing cocaine use and high levels of alcohol consumption and using an increasing number of psychoactive drugs. Moreover, low education level, having used cocaine frequently in houses and reporting cocaine binges were associated with increasing cocaine use.
  
  
  CONCLUSIONS
  A street-recruited cohort of cocaine users in Spain showed a significant reduction in cocaine use over a period of 12-24 months. High consumption of alcohol and increasing use of other psychoactive drugs decreased the probability of reducing cocaine use.
authors: Centro Nacional de Epidemiología, Instituto de Salud Carlos III, Madrid, Spain; CIBER Epidemiología y Salud Pública (CIBERESP), Madrid, Spain.
authors: José
authors: J
authors: Pulido
authors: Gemma
authors: G
authors: Molist
authors: Antonia
authors: A
authors: Domingo-Salvany
authors: M Teresa
authors: MT
authors: Brugal
authors: Albert
authors: A
authors: Sanchez-Niubò
authors: Gregorio
authors: G
authors: Barrio
authors: Luis
authors: L
authors: de la Fuente
mesh_terms: D000293:Adolescent; D000328:Adult; D000437:Alcoholism / Q000453:epidemiology / Q000523:psychology / Q000534:rehabilitation; D019970:Cocaine-Related Disorders / Q000453:epidemiology* / Q000523:psychology / Q000534:rehabilitation*; D015331:Cohort Studies; D015897:Comorbidity; D003430:Cross-Sectional Studies; D005260:Female; D006801:Humans; D008137:Longitudinal Studies; D008297:Male; D009042:Motivation; D011619:Psychotropic Drugs; D013030:Spain; D013223:Statistics as Topic; D019966:Substance-Related Disorders / Q000453:epidemiology / Q000523:psychology / Q000534:rehabilitation; D055815:Young Adult
chemical_list: D011619:Psychotropic Drugs
keywords: Cocaine; cocaine-related disorders; epidemiology; natural drug use trajectories; prospective studies; substance abuse