Background: The use of synthetic drugs has exceeded heroin to become a major public health concern in China. We aimed to estimate the trend of heroin-only, synthetic drug-only and poly-drug (heroin and synthetic drug) use during 2000-2030 period in China using existing data.
Methods: We used data from the Annual Report on Drug Control in China and peer-reviewed publications. We constructed a mathematical model to estimate the drug use trend based on Monte Carlo simulations.
Results: The best calibrated model estimated that the number of drug users would increase from 0.86 million to 3,120,059 (95% CI 2,669,214-3,570,904) during 2000-2030 period. The proportion of heroin-only users among the total drug users will decrease from 96.8% (95% CI, 96.6-97.1%) in 2000 to 36.9% (30.1-40.8%) in 2030, while the proportion of synthetic drug-only users will increase from 1.1% (0.9-1.3%) in 2000 to 57.7% (51.7-65.6%) in 2030. In contrast, the proportion of poly-drug users shared an increasing trend during 2000-2016 (from 2.1% (1.5-2.8%) to 15.1 (13.8-17.1%)) but declined to 5.5% (3.4-7.2%) in 2030. Estimated 46,370 (41,634-51,106) heroin-only users and 3767 (3481-4053) synthetic drug only users initiated poly-drug use in 2000. We observed a cross-over in 2012 where more synthetic drug-only users were initiating heroin use than heroin-only users initiating synthetic drug use. There will be estimated 2,094,052 (1,819,830-2,368,274) synthetic drug-only users and poly-drug users 211,407 (177,150-245,664) in 2030.
Conclusions: Synthetic drug use will become dominant in drug users in China, but poly-drug use of both heroin and synthetic drugs will remain substantial.
Keywords: China; Heroin; Monte Carlo simulation; Poly-drug users; Synthetic drug.
Copyright © 2019. Published by Elsevier Ltd.