Characterization of phosphatidylethanol blood concentrations for screening alcohol consumption in early pregnancy

Phosphatidylethanol is a promising tool for screening alcohol consumption during pregnancy

BACKGROUND

Prenatal alcohol exposure (PAE) is one of the leading causes of preventable developmental disabilities. A lack of objective screening methods results in an under-recognition of the phenomenon. Phosphatidylethanol (PEth) is a specific ethanol biomarker that reveals alcohol intake up to several weeks after alcohol use. So far, PEth has mostly been a tool for detecting moderate and heavy drinking. With lower PEth cut-offs, revealing even minor prenatal alcohol consumption is possible. We aimed to find out if a sensitive method for PEth analysis would give additional information about PAE and to assess the cut-off value for a positive alcohol result in prenatal screening.

METHODS

The study was an observational study of 3000 anonymous blood samples collected from the Helsinki University Hospital Diagnostic Center between June and September 2023. The Finnish Red Cross Blood Service received the samples originally for blood group typing and antibody screening as part of the prenatal blood screening program. We developed a sensitive PEth 16:0/18:1 analysis method using ultra-high-performance liquid chromatography tandem mass spectrometry (UHPLC-MS/MS) equipment after liquid-liquid extraction of PEth from whole blood. The lower limit of quantification was 1 ng/mL.

RESULTS

PEth was ≥2 ng/mL in 5.2% of the cases, ≥8 ng/mL in 2.0%, and ≥20 ng/mL in 1.0%. The detection time of PEth can be several weeks, especially with low PEth concentrations and after heavy alcohol consumption. It remained unknown whether the positive PEth tests resulted from drinking deliberately during pregnancy or before pregnancy recognition.

CONCLUSIONS

We suggest adding PEth 16:0/18:1 to a routine prenatal blood screening program with a cut-off of 2 ng/mL-and in positive cases, clinical evaluation and retesting in 2-4 weeks. In clinical settings, information on gestational week and alcohol consumption before pregnancy is relevant and needs to be considered when interpreting low PEth concentrations.

Identifying Prenatal Alcohol Exposure and Children Affected by It: A Review of Biomarkers and Screening Tools

PURPOSE

Early identification of prenatal alcohol exposure (PAE) and of those in need of services resulting from this exposure is an important public health concern. This study reviewed the existing literature on potential biomarkers and screening tools of PAE and its impact.

SEARCH METHODS

Electronic databases were searched for articles published between January 1, 1996, and November 30, 2021, using the following search terms: ("fetal alcohol" or "prenatal alcohol" or "FASD" or "alcohol-related neurodevelopmental disorder" or "ARND" or "ND-PAE") and ("screening" or "identification" or "biomarker"). Duplicate articles were electronically eliminated. Titles and abstracts were reviewed for appropriateness, and selected articles were retrieved for further analysis. Additional articles were added that were referenced in the reviewed articles or identified from expert knowledge. Information about the characteristics of the sample, the biomarker or screening tool, and the predictive validity outcome data were abstracted. A narrative analysis of the studies was then performed on the data.

SEARCH RESULTS

A total of 3,813 articles were initially identified, and 1,215 were removed as duplicates. Of the remaining articles, 182 were identified as being within the scope of the review based on title and abstract inspection, and 181 articles were successfully retrieved. Of these, additional articles were removed because they were preclinical (3), were descriptive only (13), included only self-report of PAE (42), included only mean group comparison (17), were additional duplicates (2), focused on cost analysis (9), missed predictive validity data (24), or for other reasons (23). The remaining articles (n = 48) were abstracted. An additional 13 manuscripts were identified from these articles, and two more from expert knowledge. A total of 63 articles contributed to the review.

DISCUSSION AND CONCLUSIONS

Biomarkers and screening tools of PAE and its impact fall short of ideal predictive validity characteristics. Higher specificity than sensitivity was found for many of the biomarkers and screening tools used to identify PAE and its impact, suggesting that current methods continue to under-identify the full range of individuals impacted by PAE. Exceptions to this were found in recent investigations using microRNAs related to growth and vascular development, proteomic changes associated with PAE, and combinations of markers estimating levels of various cytokines. Replications of these findings are needed across other samples to confirm the limited data available. Future research on biomarkers and screening tools should attend to feasibility and scalability of implementation. This article also recommends a systematic process of evaluation to improve early identification of individuals impacted by PAE so that harm reduction and habilitative care efforts can be implemented.

Biomarkers of moderate alcohol intake and alcoholic beverages: a systematic literature review

The predominant source of alcohol in the diet is alcoholic beverages, including beer, wine, spirits and liquors, sweet wine, and ciders. Self-reported alcohol intakes are likely to be influenced by measurement error, thus affecting the accuracy and precision of currently established epidemiological associations between alcohol itself, alcoholic beverage consumption, and health or disease. Therefore, a more objective assessment of alcohol intake would be very valuable, which may be established through biomarkers of food intake (BFIs). Several direct and indirect alcohol intake biomarkers have been proposed in forensic and clinical contexts to assess recent or longer-term intakes. Protocols for performing systematic reviews in this field, as well as for assessing the validity of candidate BFIs, have been developed within the Food Biomarker Alliance (FoodBAll) project. The aim of this systematic review is to list and validate biomarkers of ethanol intake per se excluding markers of abuse, but including biomarkers related to common categories of alcoholic beverages. Validation of the proposed candidate biomarker(s) for alcohol itself and for each alcoholic beverage was done according to the published guideline for biomarker reviews. In conclusion, common biomarkers of alcohol intake, e.g., as ethyl glucuronide, ethyl sulfate, fatty acid ethyl esters, and phosphatidyl ethanol, show considerable inter-individual response, especially at low to moderate intakes, and need further development and improved validation, while BFIs for beer and wine are highly promising and may help in more accurate intake assessments for these specific beverages.

Phosphatidylethanol in Maternal or Neonatal Blood to Detect Alcohol Exposure during Pregnancy: A Systematic Review

BACKGROUND

Alcohol consumption during pregnancy, even at low doses, may damage the fetus. Pregnant women tend to underreport their alcohol consumption generating the need for sensitive and specific biomarkers, among which PEth has emerged due to its high specificity and possibility to be measured in both maternal and neonatal blood. The aim of this study is to systematically review the latest 20 years of literature for depicting the state of the art, the limitations, and the prospects of PEth for estimating alcohol consumption during pregnancy.

MATERIALS AND METHODS

A systematic search, adhering to PRISMA guidelines, of the latest 20 years of literature through "MeSH" and "free-text" protocols in the databases PubMed, SCOPUS, and Web of Science, with time limits 1 January 2002-1 March 2022, was performed. The inclusion criteria were as follows: PEth used for detecting alcohol consumption during pregnancy, quantified in blood through liquid chromatography coupled to mass spectrometry, and full texts in the English language. Opinion papers, editorials, and narrative reviews were excluded.

RESULTS

Sixteen (16) papers were included in the present review (0.81% of total retrieved records). All the included records were original articles, of which there were seven prospective cohort/longitudinal studies, six cross-sectional studies, two observational-descriptive studies, and one retrospective study. All studies assayed PEth in at least one biological matrix; seven (7) studies quantified PEth in maternal blood, seven studies in newborn blood, and only two studies in both maternal and neonatal blood. In several included papers, PEth proved more sensitive than self-reports for identifying pregnant women with an active alcohol intake with the diagnostic efficiency improving with the increase of the maternal alcohol intake.

CONCLUSIONS

Further studies, performed on wider and well-stratified populations, are needed to drive any definitive conclusion. PEth is a promising marker for monitoring alcohol use in pregnancy; however, at the present time, its use is still limited mainly by the absence of a globally agreed interpretative cut-off, the paucity of data regarding its specificity/sensitivity, and the lack of standardization on the diagnostic efficiency of the different isoforms.

Intergenerational genetic programming mechanism and sex differences of the adrenal corticosterone synthesis dysfunction in offspring induced by prenatal ethanol exposure

We previously found that prenatal ethanol exposure (PEE) induced adrenal dysplasia in offspring, which was related to intrauterine maternal glucocorticoid overexposure. This study investigated the intergenerational genetic effect and sex differences of PEE-induced changes in the synthetic function of adrenal corticosterone in offspring, and to clarify the intrauterine origin programming mechanism. Wistar pregnant rats were gavaged with ethanol (4 g/kg bw/d) from gestation day (GD) 9-20, and F1 generation was born naturally. The F1 generation female rats in the PEE group were mated with normal male rats to produce F2 generation. Serum and adrenal glands of fetal rats and F1/F2 adult rats were collected at GD20 and postnatal week 28. PEE increased the serum corticosterone level, while diminishing the expression of adrenal steroid synthases of fetal rats. Moreover, PEE enhanced the mRNA expression of GR and HDAC1, but inhibited the mRNA expression of SF1 and reduced the H3K9ac level of P450scc in the fetal adrenal gland. In PEE adult offspring of F1 and F2 generation the serum corticosterone level, the H3K9ac level of P450scc and its expression were decreased in males but were increased in females. In NCI-H295R cells, cortisol reduced the production of endogenous cortisol, down-regulated SF1, and up-regulated HDAC1 expression by activating GR, and decreased H3K9ac level and expression of P450scc. In conclusion, PEE could induce adrenal dysplasia in offspring with sex differences and intergenerational genetic effects, and the adrenal insufficiency in male offspring was related to the induction of low functional genetic programming of P450scc by intrauterine high corticosterone through the GR/SF1/HDAC1 pathway.

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.

Distribution of Phosphatidylethanol in Maternal and Fetal Compartments After Chronic Gestational Binge Alcohol Exposure

BACKGROUND

Phosphatidylethanol (PEth) is a promising biomarker for gestational alcohol exposure. Studies show PEth accumulation in maternal and fetal blood following alcohol exposure; however, distribution of specific PEth homologues (16:0/18:1, 16:0/18:2, 16:0/20:4) in maternal and fetal blood is unknown. Additionally, PEth levels in highly vulnerable FASD targets in maternal and fetal compartments remain unexplored. We hypothesized that all 3 major PEth homologues will be detectable in the maternal and fetal blood, the maternal uterine artery (a reproductive tissue that delivers oxygen and nutrients to fetoplacental unit), and fetal brain regions following gestational binge alcohol exposure and that homologue distribution profiles will be tissue-specific.

METHODS

Pregnant rats received once-daily orogastric gavage of alcohol (Alcohol; BAC 216 mg/dl@4.5g/kg/d; BAC 289 mg/dl@6g/kg/d) or iso-caloric maltose dextrin (Pair-fed control) from gestation days (GD) 5 to 20 or 21. Following chronic exposure, maternal and fetal tissues were analyzed for PEth homologue concentrations utilizing LC-MS/MS technology.

RESULTS

All 3 PEth homologues were detected in alcohol-exposed maternal blood, fetal blood, maternal uterine artery, and fetal brain regions (hippocampus, cerebral cortex, and cerebellum). In both maternal and fetal blood, respectively, PEth 16:0/18:2 was more abundant compared to 16:0/18:1 (p < 0.0001,~66%,↑; p = 0.0159, 20.4%↑) and 16:0/20:4 (p = 0.0072,~25%↑; p = 0.0187, 19.4%↑). Maternal PEth 16:0/20:4 was ~ 42% higher than 16:0/18:1 (p = 0.0015). Maternal PEth 16:0/18:2 and 16:0/20:4 were ~ 25%↑ and ~ 20%↑ higher than in fetal blood (p < 0.05). No homologue differences were detected in the maternal uterine artery. In all fetal brain regions, PEth 16:0/18:1 was significantly higher (p < 0.0001) than 16:0/18:2 (~48 to 78%↑) and 16:0/20:4 (~31 to 62%↑) concentrations. PEth 16:0/20:4 was ~ 18% higher than 16:0/18:1 (p < 0.05) in the fetal hippocampus and cortex.

CONCLUSION

All major PEth homologues were detected in maternal and fetal blood following chronic gestational binge alcohol exposure; homologue distribution profiles were tissue-specific. This study also provides insights into PEth accumulation in critical FASD targets, specifically the maternal uterine artery and fetal brain.

High Rates of Biomarker-Confirmed Alcohol Use Among Pregnant Women Living With HIV in South Africa and Uganda

BACKGROUND

Alcohol use is common among people living with HIV and particularly harmful during pregnancy. However, objective data on alcohol use in pregnant women living with HIV (WLWH) are lacking. In areas with high levels of alcohol use generally, such as South Africa and Uganda, these data are needed to inform interventions.

METHODS

Pregnant and nonpregnant, antiretroviral therapy-naive WLWH were recruited from outpatient clinics in South Africa and Uganda. Women provided self-report data on previous three-month alcohol use and potential mental health correlates of alcohol use (depression and stigma). Blood samples were used to measure phosphatidylethanol (PEth), an objective biomarker of recent alcohol intake. We analyzed any alcohol use (ie, any self-reported use or PEth-positive [≥8 ng/mL]) and under-reporting of alcohol use (ie, no self-reported use with concurrent PEth-positive).

RESULTS

Among pregnant WLWH (n = 163, median age was 26 [interquartile range: 23-29], median gestational age was 20 weeks [interquartile range: 16-26]), 40% were using alcohol and 16% under-reported alcohol use. Neither any alcohol use nor under-reporting of alcohol use differed significantly between pregnant and nonpregnant women or by country (P > 0.05). Greater depression (but not greater stigma) was significantly associated with any alcohol use (adjusted odds ratio = 1.41, 95% confidence interval: [1.01 to 1.99]; P = 0.045).

CONCLUSIONS

Alcohol use was prevalent and under-reported among pregnant WLWH in South Africa and Uganda, similar to nonpregnant participants, and associated with depression. General health care and antenatal clinic settings present opportunities to provide integrated alcohol-based counseling and depression treatment.

Assessing prevalence of alcohol consumption in early pregnancy: Self-report compared to blood biomarker analysis

Providing appropriate antenatal and postnatal care for women who drink alcohol in pregnancy is only possible if those at risk can be identified. We aimed to compare the prevalence of alcohol consumption in the first trimester of pregnancy using self-report and blood biomarker analysis. Six-hundred routine blood samples from 2014, taken at the antenatal booking appointment, in the first trimester of pregnancy, were anonymously analysed for the presence of Carbohydrate Deficient Transferrin (CDT), a validated marker of chronic alcohol exposure (normalising 2-3 weeks from abstinence) and Gamma-glutamyltransferase (GGT), a liver enzyme elevated for up to 8 weeks after alcohol exposure. In a separate sample of women, from 2015, data taken during the antenatal visit, documenting women's self-reported alcohol consumption, were collected. The percentage of women who reported alcohol intake in the first trimester was 0.8%. This compared to 74.1% of women who reported consuming alcohol before pregnancy. CDT analysis revealed a prevalence rate of 1.4% and GGT a prevalence rate of 3.5% in the first trimester of pregnancy. Although those with elevated CDT generally had high levels of GGT, only one person was positive for CDT and GGT. Results from CDT analysis and self-report may underestimate prevalence for different reasons. GGT appeared to lack specificity, but it may have value in supporting findings from CDT analysis. Further studies using additional blood biomarkers, or a combination of blood biomarkers and self-report, may be beneficial in accurately detecting alcohol drinking history in pregnancy.

Improving screening for alcohol consumption during pregnancy with phosphatidylethanol

OBJECTIVE

The study objective was to compare rates of alcohol use between urine ethanol testing and self- reporting (Method: 1) and Phosphatidylethanol (PEth) dried blood spot testing and self-reporting (Method: 2).

METHODS

This was a prospective observational study in an obstetric clinic with universal alcohol screening.

RESULTS

Method: 1 identified 11 patients with alcohol use (5 urine and 6 self-reported); Method: 2 identified 28 (22 PEth and 6 self-reported) out of 315 patients (one patient positive for both urine and PEth). The six patients with self-reported use had negative urine and PEth testing. We had fair agreement between the two methods (282 negative and 7 positive; 289/314=92.0%; Kappa 0.32, p<0.001); method 2 identified significantly more women (McNemar, p<0.001). Combining methods: resulted in an alcohol detection rate of 10.2% (32/314).

CONCLUSION

Method: 2 identified more alcohol users than Method: 1. Combining both methods: identified the most alcohol consumption.

Phosphatidylethanol (PEth) as a Biomarker of Alcohol Consumption in HIV-Infected Young Russian Women: Comparison to Self-Report Assessments of Alcohol Use

Alcohol use is particularly deleterious for HIV-infected individuals and thus accurate assessment of alcohol consumption is crucial in this population. Phosphatidylethanol (PEth) provides an objective assessment of drinking and can be compared to self-reported alcohol assessments to detect underreporting. The purpose of this study was to identify underreporting and its potential predictors in an HIV-infected sample of young Russian women. The current study examined the concordance between a quantitative measure of PEth and self-reported recent alcohol consumption in a prospective sample of HIV-infected young women (N = 204) receiving medical care in Saint Petersburg, Russia. At baseline, 53% of participants who denied drinking in the prior 30 days tested positive for PEth (i.e., underreporters), although this rate decreased significantly at a three-month follow-up assessment. Further exploration did not identify consistent predictors of underreporting status. Quantitative PEth levels showed, at best, modest overlap to self-reported alcohol consumption among those reporting alcohol use (e.g., Spearman's r = 0.27 between PEth and total drinks past-30 days at baseline). Objective measures of alcohol consumption demonstrate modest overlap with self-report measures of use in HIV-infected young Russian women. Incorporating objective and quantifiable biological markers are essential for valid assessments of alcohol use.

How strong is the evidence for using blood biomarkers alone to screen for alcohol consumption during pregnancy? A systematic review

Accurate and early identification of women at risk from alcohol consumption during pregnancy allows education and support programmes to be targeted at those most in need. We aimed to conduct a systematic review to compare the efficacy of blood analysis and maternal self-report in detecting at risk women during pregnancy. This review investigated diagnostic accuracy. We searched four databases (Medline, Embase, Psychinfo and CINAHL) for relevant articles and conducted hand searches of recent issues of key journals in the field. No restriction was placed on inclusion in terms of publication date or language. Studies were deemed eligible if they were original research and included a direct comparison of the results of blood biomarker analysis and self-reported alcohol use for the detection of alcohol consumption in pregnant women. Quality appraisal of included studies was conducted using the QUADAS II tool. Eight studies met the inclusion criteria. Gamma-glutamyltransferase (GGT) was investigated in five studies, mean corpuscular volume (MCV) and phosphatidylethanol (PEth) in three studies and carbohydrate deficient transferrin (CDT), aspartate aminotransferase (AST), alanine aminotransferase (ALT) and whole blood associated acetaldehyde assay (WBAA) were each investigated in two studies. Although all of the studies were rated of good methodological quality, none of the biomarkers had both high sensitivity and specificity when compared to self-report. There was some evidence that a combination of biomarkers, or combining biomarkers with self-report, increases accuracy. In summary, the blood biomarkers examined were of limited use in screening for low and moderate alcohol consumption in pregnancy when compared to self-report. However, certain biomarkers, such and CDT and PEth may complement self-report and help improve the accuracy of diagnosis.

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.

Objective Measures of Prenatal Alcohol Exposure: A Systematic Review

CONTEXT

Objective measurement of prenatal alcohol exposure (PAE) is essential for identifying children at risk for adverse outcomes, including fetal alcohol spectrum disorders. Biomarkers have been advocated for use in universal screening programs, but their validity has not been comprehensively evaluated.

OBJECTIVE

To systematically review the validity of objective measures of PAE.

DATA SOURCES

Thirteen electronic databases and supplementary sources were searched for studies published between January 1990 and October 2015.

STUDY SELECTION

Eligible studies were those that evaluated the diagnostic accuracy of objective measures of PAE.

DATA EXTRACTION

Three reviewers independently verified study inclusion, quality assessments, and extracted data.

RESULTS

Twelve studies met inclusion criteria. Test performance varied widely across studies of maternal blood (4 studies; sensitivity 0%-100%, specificity 79%-100%), maternal hair (2 studies; sensitivity 19%-87%, specificity 56%-86%) maternal urine (2 studies; sensitivity 5%-15%, specificity 97%-100%), and biomarker test batteries (3 studies; sensitivity 22%-50%, specificity 56%-97%). Tests of the total concentration of 4 fatty acid ethyl esters (in meconium: 2 studies; in placenta: 1 study) demonstrated high sensitivity (82%-100%); however, specificity was variable (13%-98%).

LIMITATIONS

Risk of bias was high due to self-report reference standards and selective outcome reporting.

CONCLUSIONS

Current evidence is insufficient to support the use of objective measures of prenatal alcohol exposure in practice. Biomarkers in meconium and placenta tissue may be the most promising candidates for further large-scale population-based research.

Stability of Phosphatidylethanol in Dry Blood Spot Cards

BACKGROUND

The analysis of phosphatidylethanol, a promising direct ethanol metabolite, in dry blood spots (PEth-DBS) is advantageous due to ease of storage, transportation and minimal invasiveness of capillary blood collection. One potential application of PEth-DBS is to confirm prenatal alcohol exposure in newborns suspected of FASD; however, stability of PEth-DBS is largely unknown.

METHODS

Phlebotomized samples from 31 adults with a history of alcoholism, admitted to the University of New Mexico Emergency Department, were analyzed for blood alcohol content and pipetted onto DBS cards (13 spots per patient). The first spot was analyzed within 2 weeks of collection for a baseline PEth; the remaining 12 spots were allocated into three temperature conditions (room temperature, 4°C, -80°C) for the repeated measures analysis. In addition, 5 newborn DBS samples with a baseline PEth>LOD were obtained from a prospective cohort at UNM and re-analyzed at 4 months after storage at -80°C. A mixed linear model was fitted to examine the effects of temperature, time and temperature-time interaction on PEth degradation over the first 9 months.

RESULTS

The baseline PEth levels were 592.8 ± 86.7 ng/ml and 18.3 ± 4.8 ng/ml in adult and newborn samples, respectively. All DBS samples remained positive in successive samples in all temperature conditions. Results of mixed linear model demonstrated a significant effect of temperature (P < 0.001) on PEth degradation over 9 months.

CONCLUSIONS

PEth-DBS appears to be relatively stable, especially when stored at lower temperatures. These initial results are encouraging and highlight the PEth-DBS potential in retrospective assessment of alcohol exposure.

Could a first-trimester blood phosphatidylethanol concentration ⩾4 nM be useful to identify women with moderate-to-heavy prenatal alcohol exposure who are at high risk of adverse pregnancy outcomes?

It is accepted that blood phosphatidylethanol (PEth) concentrations are reliable biomarkers of ethanol (alcohol) exposure. We therefore conducted a preliminary study to test the hypothesis that elevated blood PEth concentrations can help to identifying women with prenatal alcohol exposure who are at higher risk of adverse pregnancy outcomes. The study included 35 first-trimester pregnant women who self-reported alcohol ingestion and had PEth blood concentration ⩾4 nM at recruitment. As a control group, 233 first-trimester pregnant women who self-reported as being either abstainers or light alcohol drinkers and had blood PEth concentrations <4 nM, were also included. All participants were followed up until completion of their pregnancies. Women with prenatal alcohol exposure and PEth concentrations ⩾4 nM had a risk ratio of spontaneous abortions of 3.21 (95%CI 0.93-11.06; P=0.074). Because of the potential implications in the prenatal care of women reporting risky alcohol exposure, the preliminary results from the present study indicate the need for testing the hypothesis in a more definitive approach.

Biomolecules and Biomarkers Used in Diagnosis of Alcohol Drinking and in Monitoring Therapeutic Interventions

BACKGROUND

The quantitative, measurable detection of drinking is important for the successful treatment of alcohol misuse in transplantation of patients with alcohol disorders, people living with human immunodeficiency virus that need to adhere to medication, and special occupational hazard offenders, many of whom continually deny drinking. Their initial misconduct usually leads to medical problems associated with drinking, impulsive social behavior, and drunk driving. The accurate identification of alcohol consumption via biochemical tests contributes significantly to the monitoring of drinking behavior.

METHODS

A systematic review of the current methods used to measure biomarkers of alcohol consumption was conducted using PubMed and Google Scholar databases (2010-2015). The names of the tests have been identified. The methods and publications that correlate between the social instruments and the biochemical tests were further investigated. There is a clear need for assays standardization to ensure the use of these biochemical tests as routine biomarkers.

FINDINGS

Alcohol ingestion can be measured using a breath test. Because alcohol is rapidly eliminated from the circulation, the time for detection by this analysis is in the range of hours. Alcohol consumption can alternatively be detected by direct measurement of ethanol concentration in blood or urine. Several markers have been proposed to extend the interval and sensitivities of detection, including ethyl glucuronide and ethyl sulfate in urine, phosphatidylethanol in blood, and ethyl glucuronide and fatty acid ethyl esters in hair, among others. Moreover, there is a need to correlate the indirect biomarker carbohydrate deficient transferrin, which reflects longer lasting consumption of higher amounts of alcohol, with serum γ-glutamyl transpeptidase, another long term indirect biomarker that is routinely used and standardized in laboratory medicine.

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

Presence of individual fatty acid ethyl esters (FAEEs) in meconium is considered to be a reliable biomarker of prenatal alcohol exposure, and their concentration has been found to be linearly associated with poor postnatal development, supporting the widely extended idea that ethanol is a non-threshold teratogen. However, a growing number of epidemiological studies have consistently found a lack of adverse short- and long-term fetal outcomes at low exposure levels. We therefore aimed to investigate the relationship between the concentration of individual FAEEs and prenatal alcohol exposure in meconium samples collected within the first 6 to 12?h after birth from 182 babies born to abstainer mothers and from 54 babies born to women who self-reported either light or moderate alcohol ingestion in the second or third trimester of pregnancy. In most cases, the individual FAEE concentrations were negligible and not significantly different (P >0.05) between exposed and control babies. The concentrations appeared to increase linearly with the dose only in the few babies born to mothers who reported >3 drinks/week. These results provide evidence that the correlation between prenatal alcohol exposure and individual FAEE concentrations in meconium is non-linear shape, with a threshold probably at 3 drinks/week.

Dose-response and time-response analysis of total fatty acid ethyl esters in meconium as a biomarker of prenatal alcohol exposure

OBJECTIVES

Little is known on how the dose and timing of exposure co-influence the cumulative concentration of fatty acid ethyl esters (FAEEs) in meconium. The objective of the study was to assess the cumulative concentration of FAEEs in meconium as a biomarker of light, moderate, or heavy prenatal alcohol exposure occurring at either first, second, or third trimesters of pregnancy.

METHODS

History of prenatal alcohol exposure was obtained in the 34th week of gestation from 294 pregnant women. Meconium was collected from their babies within the first 6 to 12 h after birth and examined for the presence of nine FAEEs.

RESULTS

No significant differences were identified between the cumulative levels of FAEEs in the meconium from the babies born to abstainers and those born to mothers with history of light-to-moderate prenatal alcohol exposure during their pregnancy.

CONCLUSIONS

Light-to-moderate prenatal alcohol exposure cannot be reliably predicted by the cumulative FAEE concentrations in meconium of exposed babies. A cumulative FAEE level of >10 nmol/g would be required to consider that prenatal alcohol exposure during the second to third trimesters occurred at risky levels in the absence of reliable maternal history of ethanol exposure.