Association between travel length and drug use among Brazilian truck drivers.
To investigate whether the use of the stimulants amphetamines and cocaine by truck drivers in Brazil was related to travel length. Truck drivers were randomly stopped by the Federal Highway Police on interstate roads in Sao Paulo State during morning hours from 2008 to 2011 and invited to participate in the project Comandos de Saúde nas Rodovias (Health Commands on the Roads). Participants were asked about the use of drugs, travel distance, and age, and gender was recorded. Samples of urine were collected and analyzed for amphetamine, benzoylecgonine (a metabolite of cocaine), and carboxytetrahydrocannabinol (THC-COOH a metabolite of cannabis) by immunological screening and quantification by gas chromatography-mass spectroscopy. Current use of amphetamine, cocaine, and cannabis was reported by 5.7%, 0.7%, and 0.3% of the truck drivers, respectively. Amphetamine, benzoylecgonine, and THC-COOH were found in urine samples from 5.4%, 2.6,% and in 1.0% of the drivers, respectively. There was a significant association between the positive cases for amphetamine and reported travel length 9.9% of urine samples from drivers who reported travel length of more than 270 km were positive for amphetamine, and 10.9% of those drivers reported current use of amphetamines. In most cases, appetite suppressants containing amphetamines had been used, but the purpose was most often to stay awake and alert while driving. Truck drivers with travel length of more than 270 km had significantly higher odds ratio (OR) for having a urine sample that was positive for amphetamine when adjusted for age as confounding factor (OR 9.41, 95% confidence interval CI, 3.97-22.26). No significant association was found between the use of cocaine or cannabis and travel length. Truck drivers who reported driving more than 270 km had significantly higher frequencies of urine samples positive for amphetamine and reported significantly more frequent current use of amphetamines than those who reported shorter driving distances.