Potential population impact of changes in heroin treatment and smoking prevalence rates: using Population Impact Measures.

BACKGROUND: The drug misuse and asthma are major health problems in urban settings. There are effective interventions to reduce cigarette smoking and also to treat heroin use; in the context of European System of Urban Health Indicators Project (EURO-URHIS), we explored the use of Population Impact Measures (PIMs) to describe the potential for increase in methadone use and reduction in cigarette smoking to reduce deaths -from heroin use- and asthma events in examples of urban populations. METHODS: The two PIMs calculated here are the Number of Events Prevented in your Population (NEPP) and the Population Impact Number of Eliminating (or reducing the prevalence of) a Risk Factor (PIN-ER-t). RESULTS: Increasing methadone treatment uptake from its current levels to 90% would prevent 21 (95% CI: 11-34) deaths in Manchester City, 218 (95% CI: 114-339) in Greater London and overall 1 243 (95% CI: 641-1953) in England in 1 year. In males 2 (95% CI: -22 to 28), 27 (95% CI: -296 to 363) and 170 (95% CI: -1757 to 2186) and in females 36 (95% CI: 6-70), 0 and 2312 (95% CI: 934-3783) fewer asthma cases per year would have been expected in Manchester City, Greater London and overall in England respectively, if the smoking prevalence is reduced from current levels to 20% in both sexes. CONCLUSIONS: PIMs provide estimates of absolute risk and benefit to a total population, of potential use to policy-makers since current practice and intervention goals are taken into account.