Association between routes of drug administration and all-cause mortality among drug users

Abstract

Mortality among drug users based upon routes of administration (ROA) is less studied. We examined deaths by ROA, and association between ROA and all-cause deaths. Data of 2766 primary users of opiates and stimulants who sought treatment in Helsinki, Finland, from 1997 to 2008 were linked to the national cause-of-death register. Cox regression models were used to compute adjusted hazard ratios (aHRs) for all-cause deaths, with 95% confidence intervals (CIs). There were statistically significant differences in all-cause deaths by ROA reported at baseline interview (p = 0.012): 12.7% (n = 251/1976) among intravenous (IV) drug users, 11.5% (n = 27/235) among oral users, 7.9% (n = 12/152) among smokers, 6.9% (n = 19/276) among snorters, and 16.5% (n = 21/127) among those with unspecified ROA. IV users died more from accidental overdose relative to other specified routes (p = 0.036). All nine HIV and all three hepatitis C deaths occurred among IV users. The hazard for all-cause death was lower among smokers compared to IV users (aHR: 0.52 (95%CI: 0.28–0.97) after adjusting for gender, homelessness, drug use behaviours, and psychiatric comorbidities present at baseline. Deaths occurred in all groups: drug users in general need to be educated that no route of drug administration is harmless. Preventive and intervention measures should target all ROA.