The best predictor of earlier regular heroin use is initial heroin use at a younger age, according to Eric A. Woodcock and his associates at Wayne State University, Detroit.
The investigators analyzed self-reported data from 562 out-of-treatment, chronic heroin users, aged 18-55 years. People with psychiatric conditions, such as major depression, anxiety disorders, and schizophrenia, were excluded.
Mr. Woodcock and his associates found that alcohol, tobacco, marijuana, or a combination of those substances accounted for 88% of substances first used by the participants. Age at initial heroin use accounted for 72% of the variance, and regular alcohol and tobacco use were the best between-substance predictors, accounting for 8% of the variance in age. Earlier initial use was associated with faster progression to regular use, longer use duration, and more negative lifetime consequences. Nearly 80% of participants followed the gateway hypothesis, and those who did not had a younger initial use age, used for a longer period of time, and used more often.
“Taken together, these results indicate the trajectory of heroin use significantly influences current heroin use characteristics that are associated with a more burdensome disorder and worse treatment outcomes,” the investigators said. “These findings highlight the importance of early intervention.”
Find the full study in Addictive Behaviors (doi: 10.1016/j.addbeh.2015.02.014).