30-Year trajectories of heroin and other drug use among men and women sampled from methadone treatment in California (2011)

BACKGROUND This study examines 30-year trajectories of heroin and other drug use among men and women who were in methadone maintenance treatment in California in the late1970s and interviewed in 1978–1981.
METHODS Nearly half (N = 428; 46.8%) of the original study sample (N = 914) was deceased. Of the remaining 486 subjects, 343 (44.3% female) completed a follow-up interview in 2005–2009 (70.6% of those not deceased). Average age at follow-up was 58.3 (SD = 4.9) years for males and 55.0 (SD = 4.1) years for females. Longitudinal data was obtained on their drug use, treatment participation, and criminal justice status over the follow-up period. Trajectory group modeling was used to identify distinctive trajectory groups based on monthly averages of heroin and other drug use per year; group differences were examined.
RESULTS Four heroin and five alcohol and other drug (AOD) trajectory groups were identified. A greater proportion of women (60%) were in the “rapid decrease” heroin group (odds of use less than 10% by 10 years following initiation of use) as compared with the other groups. More rapid decrease of heroin use was associated with increases in AOD use, whereas a gradual decrease in heroin use was associated with a gradual decrease in AOD use. More school problems and earlier age at onset of heroin use and first arrest were associated with more persistent heroin use.
CONCLUSION Heroin-use trajectories were linked with changes in AOD use. Childhood antecedents of heroin-use trajectories were identified as well as gender differences.