Individual-level and neighborhood-level shifts in mortality patterns among drug poisoning deaths in a high-density Asian city: a territory-wide, case-only analysis.

Misuse of registered drugs (e.g. opioid pain relievers) could be a rising trend among vulnerable subpopulations in Hong Kong other than illegal drug use (heroin). Health officials should provide more advice and support on drug information. Specifically, an improved health system with education regarding the appropriate use of registered drugs for medical treatments should be provided to mid-/high-income and local-born individuals.