Drug induced mortality: a multiple cause approach on Italian causes of death Register

Abstract

Background: Drug-related mortality is a complex phenomenon that has several health, social and economic effects. In this paper trends of drug-induced mortality in Italy are analysed. Two approaches have been followed: the traditional analysis of the underlying cause of death (UC) (data refers to the Istat mortality database from 1980 to 2011), and the multiple cause (MC)analysis, that is the analysis of all conditions reported on the death certificate (data for 2003-2011 period).

Methods: Data presented in this paper are based on the Italian mortality register. The selection of Icd codes used for the analysis follows the definition of the European Monitoring Centre for Drugs and Drug Addiction. Using different indicators (crude and standardized rates, ratio multiple to underlying), the results obtained from the two approaches (UC and MC) have been compared. Moreover, as a measure of association between drug-related causes and specific conditions on the death certificate, an estimation of the age-standardized relative risk (RR) has been used.

Results: In the years 2009-2011, the total number of certificates whit mention of drug use was 1,293, 60% higher than the number UC based. The groups of conditions more strongly associated with drug-related causes are the mental and behavioral disorders (especially alcohol consumption), viral hepatitis, cirrhosis and fibrosis of liver, AIDS and endocarditis.

Conclusions : The analysis based on multiple cause approach shows, for the first time, a more detailed picture of the drug related death; it allows to better describe the mortality profiles and to re-evaluate  the contribution of a specific cause to death.