Factors associated with alcohol and drug use among traffic crash victims in southern Brazil.

Objective: To investigate the prevalence of and factors associated with alcohol- or drug-related traffic crashes (TC) in a sample of TC victims who were admitted to the two emergency rooms of Porto Alegre in southern Brazil.

Methods: A cross-sectional study with consecutive samples was used. Victims of non-fatal TCs (as drivers, passengers or pedestrians) who had presented at emergency rooms during the 45 days of data collection were selected. Subjects participated in a structured interview, were breathalyzed and underwent salivary drug testing. A multinomial logistic regression model was used to verify factors associated with alcohol or drug use.

Results: Of the 609 victims who participated in the interview, 72% were male, and the median age was 29 years (interquartile range 23.0-40.0 years). The drivers were mostly men (p<0.001), with a higher binge drinking rate (p=0.003) and marijuana use (p=0.005) than seen in pedestrian and passengers. The prevalence of a positive blood alcohol concentration (BAC) ranged from 7.8% among the drivers to 9.2% among the pedestrians (p=0.861), and the cannabis prevalence was 13.3% among the drivers. The variables associated with an alcohol-related accident were binge drinking in the prior 12 months (OR 2.4; CI 95% 1.1-5.1) and coming from a party/bar (OR 8.7; CI 95% 2.8-26.7). Alcohol abuse or dependence increased by 5.2-fold the chance of another substance-related TC.

Conclusion: The large number of individuals found in TC-related emergency room visits in a short time frame is evidence of the Brazilian epidemic of TC. The data showed that alcohol abuse or dependence also increases the risk of intoxication by other drugs, and they point to alcohol and drug use as a major problem requiring specific TC-related public policies and law enforcement.