Assessment of fitness to drive in correlation with narcotic and psychotropic drug use. Epidemiologic study in Verona

Driving under the influence of drugs is a serious problem for road traffic safety. According to the Italian Road Traffic Code, the driving licence must not be issued to anyone who abuses, is addicted to, or suffers for dependence to illicit or psychotropic drugs. The diagnosis of such clinical conditions is performed by Provincial Medical Commissions of the Public Health Service also on the basis of drugs of abuse testing results on urine and/or hair samples. This study aimed at examining test results obtained by the Forensic Toxicology laboratory of the Department of Public Health & Community Medicine, University of Verona, upon request of the local Medical Commission, over the period 2003-2008 with the purposes of (i) defining trends in drug abuse in the examined population (ii) identifying specific risk factors for testing positive and for relapse, (iii) selecting the most effective and efficient analytical strategy to detect illicit drugs use. During the study period, cocaine was the most frequently detected illicit drug. The comparison of results from urine and hair testing confirmed the complementary features of these two biological substrates and the importance to have both data in order to increase the sensitivity in detecting illicit drug use. Moreover, this study showed that testing for driving fitness is an effective deterrent to illicit drug use, as only about one quarter of subjects testing positive at the first testing are still positive at the second testing.