Signs of altered psychomotor capacity and use of alcohol and other drugs among nightclub patrons who drive in the city of São Paulo, Brazil

Objectives: To investigate the occurrence of signs of altered psychomotor capacity (SAPC) associated with the violation of the dry law at the exits of nightclubs in the city of São Paulo, Brazil.

Methods: Data from drivers participating in the Balada com Ciência project were used. Alcohol dosages were measured with breathalyzer test. The use of other drugs was obtained by interviewees’ self-report. SAPC (speech, walking, glazed eyes, and alcohol odor) were verified by the interviewers at the time of the interview and categorized as “no sign” or “at least one sign”. All measurements were evaluated at the exit of the nightclubs. The population description considered the sample weighting. Logistic regression analysis evaluated the association between the occurrence of SAPC, alcohol and other drugs use, controlling for sociodemographic variables.

Results: At nightclubs, the SAPC among drivers are about 8 times higher when the breath alcohol concentration is above 0.05 mg/L if compared with those who did not drink alcohol, and about 30 times higher when the alcohol concentration was ≥ 0.34 mg/L in exhaled air. This finding is not generally verified in the literature for those who report the use of drugs inside nightclubs, which is interesting, since 20.4% of the interviewed population reported using drugs in the places surveyed.

Conclusion: This study suggests the potential of using the Perham (2007) physical test for alcohol intoxication in sobriety checkpoints at the exit of nightclubs. However, the verification of these signs is not enough for the identification of drug use by drivers.