PHOSPHATIDYLETHANOL IN BLOOD AS A MARKER OF ETHANOL-CONSUMPTION IN HEALTHY-VOLUNTEERS - COMPARISON WITH OTHER MARKERS

Phosphatidylethanol is a ''pathological'' phospholipid, formed via the action of phospholipase D only in the presence of ethanol. The presen t study was made to elucidate how different levels and patterns of alc ohol intake affect: blood levels of phosphatidylethanol in comparison with other markers of abuse, We used a new HPLC-evaporative light-scat tering detection technique for phosphatidylethanol quantitation, This method had a total coefficient of variation of <20% at the detection l imit of 0.2 nmol, equaling 0.8 mu mol/liter of whole blood. Two groups were studied. (a) Five healthy volunteers were given 32 to 49 g of et hanol in a single dose, to give blood ethanol levels of similar to 25 mmol/liter after 30 to 60 min. Phosphatidylethanol, carbohydrate-defic ient transferrin (CDT), and blood ethanol were measured before and aft er the intake. (b) Twelve student volunteers were studied during a 3 w eek period of prolonged alcohol consumption (total estimated intake: 1 334 +/- 488 g, mean +/- SD) and phosphatidylethanol, serum-CDT, gamma- glutamyltransferase, and blood ethanol were measured at the start of t he period (day 1) and twice at the end of the period (days 18 and 21). In group (a), no phosphatidylethanol was detected at any time after e thanol dosage/intake. In group (b), no blood phosphatidylethanol or bl ood ethanol could be demonstrated at the start, and serum-CDT was belo w the discrimination limit (1.3%) in all persons. No phosphatidylethan ol was detected in those four persons with the lowest intake(742 +/- 1 50 g), However, the remaining eight persons had detectable levels of p hosphatidylethanol (1.0 to 2.1 mu mol/liter), and these had a higher t otal intake (1630 +/- 389 g). There was a statistically significant (p = 0.02) increase In serum CDT for 3 weeks. However, only 3 of 12 pers ons increased above the discrimination limit The present results indic ate that a substantial alcohol intake is needed to elevate blood phosp hatidylethanol, In comparison with serum-CDT, blood phosphatidylethano l appears more sensitive.