Hair ethylglucuronide and blood phosphatidylethanol detection of 4 DUI driver risk factors

Various alcohol biomarker types, sourced from urine, blood and hair predict interlock fail rates. Which biomarkers best predict recidivism and which would be the best components in a panel of markers to help evaluate drink-driving offenders? The aim is to characterize risk indicators and outcomes among interlock participants. This paper focuses on new analyses comparing different marker types in prediction of 4 categories of criterion correlates or outcomes: recidivism, alcohol dependence, ordinal fail rates, maximal BAC attained during the first two interlock months. Interlock offenders gave consent and interviews (for DSM4 diagnosis), self-report assessments and contributed blood, hair, urine for analysis. ROC analysis of interlock BAC test records and driver records yielded predictor and outcome variables. Hair ethylglucuronide (EtG) was the strongest predictor of baseline alcohol dependence and subsequent recidivism; it shared honors with phosphatidylethanol (Peth) for predicting maximal recorded levels of BAC. PEth was the strongest predictor of failed BAC tests across 5 ordinal combinations of failed BAC tests, both overall and morning tests. Hair EtG above either the 30 pg/mg cutoff (2/3 of drivers above) or the 50 pg/mg (1/3 of drivers above) is strongly associated with other self report, diagnostic and interlock-based indicators of alcohol driving risk. PEth and hair EtG are the two best component alcohol biomarkers to include in a comprehensive monitoring panel for driver alcohol risk.