Longitudinal patterns of cocaine use among adolescents

Developmental patterns of cocaine use were examined in a longitudinal sample of 1,308 male and female adolescents. The data indicate that substantial increases in use occurred between 15 and 18 and between 18 and 21 years old. Although there were developmental changes, there were no significant increases over time for same aged individuals. Gender differences within age groups were not statistically significant, although some differences were apparent. Examinations of intraindividual changes in cocaine use among continuous users indicate significant individual increases in all measures of cocaine use over a 3-year period. While continuous users increased their use of cocaine, they experienced decreases in their frequency of use of alcohol, marijuana, and other drugs. Analyses also suggest that those individuals who initiated cocaine use between T1 and T2 were already different from their age peers in terms of their cigarette, alcohol, and marijuana use at T1. Overall, the findings suggest that patterns of cocaine use may be more dependent upon the number of years of use rather than on the age of the user.