Characteristics of Methamphetamine-Positive Drivers Killed in Motor Vehicle Crashes in San Diego County

Background: Methamphetamine abuse has been a persistent problem in San Diego County, with positive toxicology results found in over 10% of the cases tested by the County Medical Examiner (ME) since 2000. This analysis examines characteristics of drivers killed in motor vehicle crashes who had positive toxicology results for methamphetamine. Methods: We identified cases with positive toxicology results from the County of San Diego Medical Examiner's toxicology database and linked those records with the corresponding crash record from the California Statewide Traffic Records System (SWITRS) for incidents that occurred between 2000 and 2007. We then compared these cases with drivers who died but did not test positive for methamphetamine. Results: During this eight year period, out of 902 ME cases, 86 (9.5%) tested positive for methamphetamine. Meth-positive drivers were similar to others in terms of age, but more likely to be male (81% vs. 72%), Hispanic (31% vs. 20%), or unmarried (71% vs. 59%). Meth-positive drivers were also more likely to collide with objects (56% vs. 38%), and to be at fault in the collision (93% vs. 78%). Sixty percent of meth-positive drivers were unrestrained, with 33% being ejected. Conclusions: The proportion of fatal motor vehicle crashes involving methamphetamine is unacceptably high. This drug contributes to the hazard by altering behavior and judgement, with those who use it less likely to follow basic safety precautions at the same time that they take needless risks.