Relationship between alcohol intake based on daily smartphone-reported consumption and PEth concentrations in healthy volunteers.

AIMS: To investigate the association between alcohol consumption registered daily with a digital smartphone-based diary and concentration of phosphatidylethanol (PEth) 16:0/18:1 in a population without a known alcohol use disorder (AUD), and evaluate whether prospective registration of alcohol consumption is better than retrospective registration and if the association between alcohol intake and PEth was affected by sex or body mass index (BMI). METHODS: A total of 41 women and 21 men without AUD-diagnosis registered their alcohol consumption prospectively with a digital diary for 14 days, and retrospectively with the Timeline Followback method in the same time interval. PEth was measured before and after the registration period. RESULTS: The correlation between alcohol consumption and PEth varied from 0.65 to 0.87. It did not depend significantly on the reporting method, and was not influenced by sex or BMI. Based on the regression coefficient, a reduction of alcohol consumption by two alcohol units (26 g of pure ethanol) per day would lead to a reduction of the PEth concentration of about 0.1 µmol/l, and vice versa. CONCLUSIONS: There was a good correlation between PEth concentration and alcohol consumption, both when alcohol consumption was reported prospectively and retrospectively. The preferred cut-off for PEth should be adjusted to the level of alcohol consumption considered harmful and a purposeful trade-off between sensitivity and specificity. In order to identify persons with a daily alcohol consumption of more than two or three units of alcohol with a sensitivity of 80% or 90%, we suggest a cut-off of around 0.1 µmol/l.

Phosphatidylethanol as Blood Biomarker of Alcohol Consumption in Early Pregnancy: An Observational Study in 4,067 Pregnant Women.

BACKGROUND: The teratogenic effects of alcohol are well documented, but there is a lack of screening methods to detect alcohol use during pregnancy. Phosphatidylethanol 16:0/18:1 (PEth) is a specific and sensitive biomarker reflecting alcohol intake up to several weeks after consumption. The aim of this study was to investigate the prevalence of positive PEth values as an indicator of early prenatal alcohol exposure in a general population of pregnant women. METHODS: Rhesus typing is routinely performed in Norway in all pregnancies around gestational week 12. Rhesus-negative women have an additional test taken around week 24. Blood samples submitted to St. Olav University Hospital in Trøndelag, Norway, for Rhesus typing during the period September 2017 to October 2018 were collected. A total of 4,533 whole blood samples from 4,067 women were analyzed for PEth (limit of quantification of 0.003 µM). RESULTS: Fifty-eight women had a positive PEth sample. Of these, 50 women were positive around gestational week 12, 3 women were positive around week 24, and in 5 cases, the timing was unknown. There were no significant differences in proportions of women with positive PEth values related to age, or rural versus urban residency. CONCLUSION: In an unselected pregnant population in Norway, 1.4% had a positive PEth sample around gestational week 12, whereas 0.4% had a positive sample around week 24. The use of PEth as an alcohol biomarker should be further investigated as a diagnostic tool in the antenatal setting.