Evaluation of Phosphatidylethanol Elimination in Alcohol Use Disorder Patients Undergoing Withdrawal Treatment

Abstract

Phosphatidylethanol (PEth) is used to monitor alcohol consumption in alcohol use disorder (AUD). In this study, we aim to evaluate the elimination time of PEth with regard to the clinically established 200 and 20ng/ml cutoffs for PEth 16:0/18:1. Data from 49 patients undergoing treatment for AUD were evaluated. PEth concentrations were measured at the beginning and repeatedly during the treatment period of up to 12weeks to monitor the elimination of PEth. We evaluated the time in weeks until the cutoff concentrations of <200 and <20ng/ml were achieved. The correlation between the initial PEth concentration and the number of days until the PEth concentration had dropped below 200 and 20ng/ml was assessed by calculating Pearson's correlation coefficients. The initial PEth concentrations ranged from <20 to >2500ng/ml. In 31 patients, the time until the cutoff values were reached could be documented. Even after 6weeks of abstinence, PEth concentrations above the cutoff of 200ng/ml could still be detected in two patients. A strong significant positive correlation was found between the initial PEth concentration and the time required to drop below the two cutoffs. A waiting period of more than 6weeks after declared abstinence should be granted for individuals with AUD before using only one single PEth concentration to assess the consumption behavior. However, we recommend to always use at least two PEth concentrations for the evaluation of alcohol-drinking behaviors in AUD patients.