Tracking the evolution of drug abuse in China, 2003-10: a retrospective, self-controlled study.

AIM

To characterize trends in drug abuse in China before and after the 2005 initiation of the 'People's War on Drugs'.

DESIGN

Retrospective self-controlled study.

SETTING

Annual, nation-wide surveillance from 2003 to 2010 of all registered drug users in China's National Surveillance System on Drug Abuse (NSSDA).

PARTICIPANTS

A total of 1,184,124 drug users registered in NSSDA were involved in this study and were classified into three groups based on registered dates-pre-war group (n=230,278) registered 2003-04, phase I group (n=518,651) registered 2005-07 and phase II group (n=435,195) registered 2008-10.

MEASUREMENTS

Indicators included proportions of:(i) new and relapsed drug users, (ii) heroin and synthetic drug users among new users, (iii) people aged 35 years or younger and (iv) women. Comparisons were made across groups using annual data to describe temporal trends.

FINDINGS

Between 2003 and 2010 the proportion of heroin users decreased by 52.3% and synthetic drugs use increased 860.7% among new users, while a 12.8% decrease in the proportion of heroin users and a 918.8% increase in synthetic drug use in all users was detected. Compared with the pre-war group, the proportion of relapsed users decreased 2.6% and 29.1% in the phase I and phase II groups, respectively, but a significant increase in the proportion of new users was found in phase I (OR=1.24, CI=1.15-1.35, p<0.0001), followed by an apparent decrease in phase II compared with phase I (OR=0.75, CI=0.70-0.80, p<0.0001). Similarly, the proportion of heroin users decreased 15.1 and 24.2% among new drug users in phase I and phase II in comparison with the pre-war group.

CONCLUSION

The decrease in proportions of drug users in China between 2003/4 and 2008/10 may suggest some positive influence of the 'People's War on Drugs', especially in the decreased proportion of relapsed users. In contrast, there was a rapid increase in new synthetic drug use over the same period.