Is there epidemiological evidence to support the idea that a cocaine dependence syndrome emerges soon after onset of cocaine use?

The present study uses latent class methods and multiple regression to shed light on hypothesized cocaine dependence syndromes experienced by community residents, who initiated cocaine use within 24 months of survey assessment, and explores possible variation in risk. Identified within public use data files from the United States National Household Surveys on Drug Abuse (NHSDA), and with assessments completed between 1995 and 1998, the study sample consists of 927 recent-onset cocaine users, defined as having initiated cocaine use no more than 24 months prior to assessment (approximate median elapsed time since onset of use approximately 12-13 months). The NHSDA included items to assess seven clinical features often associated with cocaine dependence, which were used in latent class modeling. Empirically derived latent classes, in conjunction with prior theory, tend to support a three-class solution, according to which 4% of recent-onset users are members of a class that resembles the DSM-IV cocaine dependence syndrome (mean: 5.4 clinical features (CF)); 16% might be in a cocaine dependence prodrome (mean: 2.4 CF); 80% of recent-onset cocaine users had few or no clinical features (mean<1 CF). Results from latent class regressions indicate that susceptibility to rapid transition from first cocaine use to onset of the LCA-assigned cocaine dependence syndrome might depend upon whether the user starts smoking crack-cocaine and, independently, age at first cocaine use.