Identification of unhealthy alcohol use by self-report and phosphatidylethanol (PEth) blood concentrations in an acute psychiatric department

Abstract

Background: The use of standard screening methods could improve the detection rate of unhealthy alcohol use in patients admitted to psychiatric acute and emergency departments. The aim of the present study was to investigate the ability of the alcohol biomarker phosphatidylethanol (PEth) to identify patients with high levels of alcohol consumption prior to admission.

Methods: The data were prospectively collected at admittance to an acute psychiatric department in the period January 2016 to June 2017. A blood sample for the analysis of PEth was available from 177 patients. We compared the PEth concentrations with the Alcohol Use Disorders Identification Test (AUDIT) scores during the hospital stay, and psychiatric diagnoses at discharge.

Results: A total of 45.8% of the patients had a PEth concentration ≥ 0.03 μmol/L, indicating significant alcohol consumption. AUDIT scores consistent with unhealthy alcohol use were present in 51.7%. There was a significant positive correlation between PEth concentrations and AUDIT scores (r = 0.631, p < 0.001). PEth was above the detection limit of 0.03 μmol/L in 19% of those reporting an average daily intake of zero alcohol units per day during the last week before admission. PEth concentrations were significantly higher among those with an alcohol diagnosis than among those without such a diagnosis (0.82 μmol/L vs. 0.09 μmol/L, p = 0.001).

Conclusion: PEth provides supplementary information on recent alcohol consumption in a psychiatric population and would be particularly helpful in patients unable or unwilling to give such information at admission.

Keywords: Alcohol use disorder; Mental health; Phosphatidylethanol; Psychiatry.

Fig. 1

Flow diagram of patient inclusion into the data analysis. GAP study = Genetic and Affective Prediction Study, PEth = phosphatidylethanol, AUDIT = Alcohol Use Disorders Identification Test

Fig. 2

Distribution of phosphatidylethanol (PEth) concentrations in the study population

Fig. 3

Boxplots of hosphatidylethanol (PEth) concentrations by: a Alcohol Use Disorders Identification Test (AUDIT) score (n = 60, b average daily alcohol consumption the last week prior to hospitalization (n = 60) and c) diagnosed with alcohol disorder (n = 177). Two male patients in figure a) and b) with PEth concentrations above 1.5 μmol/L are not shown to increase readability. One of these had a PEth concentration of 2.00 μmol/L, no alcohol diagnosis, an AUDIT score of 11 and reported drinking 1-3 alcohol units per day. The other had a PEth concentration of 3.03 μmol/L, an alcohol diagnosis, an AUDIT score of 14 and reported drinking ≥4 alcohol units per day. In figure c) six patients with PEth concentrations above 1.5 μmol/L are not shown. Boxes represent the first quartile and third quartile, the central line represents median, whiskers represent minimum and maximum levels excluding outliers. Circles represent outliers with values between 1.5 and 3 times the interquartile range, the asterisks represent outliers more than 3 times the interquartile range

Fig. 4

Receiver operating characteristics (ROC) curves of phosphatidylethanol (PEth) as a test for: a an AUDIT score of eight and above, b an average daily consumption of four or more alcohol units the last week, and c diagnosed with alcohol disorder. AUC = area under the ROC curve. Asterisks indicate the location of Youden’s index in each curve, with details found in the embedded frames