Abstract
AIMS: To compare the performance of short- and long-term alcohol biomarkers for the evaluation of alcohol drinking in employment-related health controls. METHODS: The 519 blood samples originated from 509 patients (80% men) presenting at occupational health units and medical centers at employment agencies for the evaluation of risky drinking. The laboratory investigation comprised the measurement of phosphatidylethanol (PEth 16:0/18:1), carbohydrate-deficient transferrin (CDT; % disialotransferrin), gamma-glutamyl transferase (GGT), mean corpuscular volume (MCV), ethanol and ethyl glucuronide (EtG). RESULTS: Many samples tested positive for acute (57%) and chronic (69%) alcohol biomarkers. PEth was the single most positive biomarker (64%; cut-off 0.05 μmol/l or 35 μg/l) and the only positive chronic biomarker in 100 cases. The highest PEth concentrations were seen in samples positive for all chronic biomarkers, followed by those also being CDT positive (cut-off 2.0%). All 126 CDT-positive samples were positive for PEth using the lower reporting limit (≥0.05 μmol/l) and for 114 cases (90%) also using the higher limit (≥0.30 μmol/l or 210 μg/l). In the CDT-positive cases, the PEth median concentration was 1.71 μmol/l, compared with 0.45 μmol/l for the CDT-negative cases (P < 0.0001). PEth and CDT values were correlated significantly (r = 0.63, P < 0.0001). Among the EtG-positive cases (≥1.0 ng/ml), 95% were also PEth positive, and all ethanol-positive cases (≥0.10 g/l) were also PEth positive. CONCLUSIONS: For optimal detection of drinking habits, using a combination of short- and long-term alcohol biomarkers provided best information. PEth was the single most positive alcohol biomarker, whereas GGT and MCV offered little additional value over PEth and CDT.