Linear Versus Non-Linear Dose-Response Relationship Between Prenatal Alcohol Exposure and Meconium Concentration of Nine Different Fatty Acid Ethyl Esters

Quantifying fetal alcohol exposure by meconium fatty acid ethyl esters (FAEE); association with adverse fetal outcomes and population estimates of fetal alcohol exposure

Fetal Alcohol Spectrum Disorder (FASD) describes the wide range of adverse physical, behavioral and cognitive effects resulting from ethanol exposure during embryonic and fetal development. Identification of children suffering from FASD is often difficult, as abuse of ethanol during pregnancy is a heavily stigmatized behavior that receives little prenatal screening attention in routine care. Over the last 3 decades, measurement of the ethanol metabolites fatty acid ethyl esters (FAEE) has emerged as a useful tool to detect in the neonatal period fetal alcohol exposure starting from mid gestation. This review aims at updating clinicians and researchers on the validity and utility of this biological marker in two aspects: The association with adverse fetal outcomes and in generating population estimates of fetal alcohol exposure.

Prenatal alcohol exposure prevalence as measured by direct ethanol metabolites in meconium in a Native American tribe of the southwest

BACKGROUND

Although fetal alcohol spectrum disorders represent a significant public health problem, Native Americans are underrepresented in population and targeted screening programs. Prior reports suggest that Native American tribal communities may have a higher prevalence of alcohol use during pregnancy; however, systematic examination using ethanol biomarkers is lacking.

METHODS

This study utilized data collected through the Navajo Birth Cohort Study (NBCS)-a birth cohort study of a Southwestern tribal community. Prevalence of prenatal alcohol exposure (PAE) was assessed by a battery of meconium biomarkers among 333 NBCS participants. Meconium samples were analyzed for nine individual fatty acid ethyl ester (FAEE) species, ethyl glucuronide (EtG), and ethyl sulfate (EtS) by LC-MS/MS.

RESULTS

Participants were recruited from five hospitals at the Navajo Nation located in Arizona (Chinle, Tséhootsooí, Tuba City) and New Mexico (Gallup, Shiprock). All participants identified as Native American; most reported a personal income of <$20,000 per year (71.3%), and ≤high school education (55.3%). The most prevalent biomarker was EtS (7.8%) followed by ethyl oleate (6.9%); 5.4% of the sample were positive for at least two biomarkers.

CONCLUSIONS

Results of this study on the prevalence of PAE in the Navajo Nation, obtained for the first time with an objective comprehensive panel of meconium biomarkers, indicate that the rates in the NBCS may be comparable to the general U.S. population and are in accord with recent U.S. national survey estimates. Our findings emphasize that drinking behaviors among Native American communities in the United States can vary, and generalization across all Native American populations is not warranted.

Biomarkers for the Detection of Prenatal Alcohol Exposure: A Review

Alcohol exposure during pregnancy can cause adverse effects to the fetus, because it interferes with fetal development, leading to later physical and mental impairment. The most common clinical tool to determine fetal alcohol exposure is maternal self-reporting. However, a more objective and useful method is based on the use of biomarkers in biological specimens alone or in combination with maternal self-reporting. This review reports on clinically relevant biomarkers for detection of prenatal alcohol exposure (PAE). A systematic search was performed to ensure a proper overview in existing literature. Studies were selected to give an overview on clinically relevant neonatal and maternal biomarkers. The direct biomarkers fatty acid ethyl esters (FAEEs), ethyl glucuronide (EtG), ethyl sulfate, and phosphatidylethanol (PEth) were found to be the most appropriate biomarkers in relation to detection of PAE. To review each biomarker in a clinical context, we have compared the advantages and disadvantages of each biomarker, in relation to its window of detectability, ease of collection, and the ease and cost of analysis of each biomarker. The biomarkers PEth, FAEEs, and EtG were found to be applicable for detection of even low levels of alcohol exposure. Meconium is an accessible matrix for determination of FAEEs and EtG, and blood an accessible matrix for determination of PEth.