The validity of phosphatidylethanol in dried blood spots of newborns for the identification of prenatal alcohol exposure

Methods applied to neonatal dried blood spot samples for secondary research purposes: a scoping review

This scoping review aimed to synthesize the analytical techniques used and methodological limitations encountered when undertaking secondary research using residual neonatal dried blood spot (DBS) samples. Studies that used residual neonatal DBS samples for secondary research (i.e. research not related to newborn screening for inherited genetic and metabolic disorders) were identified from six electronic databases: Cochrane Library, Cumulative Index to Nursing and Allied Health Literature (CINAHL), Embase, Medline, PubMed and Scopus. Inclusion was restricted to studies published from 1973 and written in or translated into English that reported the storage, extraction and testing of neonatal DBS samples. Sixty-seven studies were eligible for inclusion. Included studies were predominantly methodological in nature and measured various analytes, including nucleic acids, proteins, metabolites, environmental pollutants, markers of prenatal substance use and medications. Neonatal DBS samples were stored over a range of temperatures (ambient temperature, cold storage or frozen) and durations (two weeks to 40.5 years), both of which impacted the recovery of some analytes, particularly amino acids, antibodies and environmental pollutants. The size of DBS sample used and potential contamination were also cited as methodological limitations. Residual neonatal DBS samples retained by newborn screening programs are a promising resource for secondary research purposes, with many studies reporting the successful measurement of analytes even from neonatal DBS samples stored for long periods of time in suboptimal temperatures and conditions.

The Impact of Prenatal Alcohol Exposure on Longitudinal Growth, Nutritional Status, and Insulin-Like Growth Factor 1 in Early Childhood in Leyte, the Philippines

OBJECTIVE

To assess the impact and potential mechanistic pathways of prenatal alcohol exposure (PAE) on longitudinal growth and nutritional status in early childhood.

STUDY DESIGN

A cohort of 296 mother-infant dyads (32% with PAE vs 68% unexposed) were recruited in Leyte, the Philippines, and followed from early gestation through 24 months of age. PAE was assessed using serum phosphatidylethanol (PEth) captured twice prenatally and in cord blood and supplemented with self-reported alcohol consumption. Linear mixed models were used to examine longitudinal effects of PAE on growth from birth through 2 years including key potential mediating factors (placental histopathology, and infant serum leptin and Insulin-like Growth Factor 1 [IGF-1]).

RESULTS

After adjusting for potential confounders, we found that PAE was significantly associated with a delayed blunting of linear growth trajectories (height-for-age z-score, body length) and weight (weight-for-age z-score, body weight) that manifested between 4 and 6 months and continued through 12-24 months. PAE was also associated with a decreased rate of mid-upper-arm circumference growth from birth to 12 months, and a lower mean IGF-1 levels at birth and 6 months.

CONCLUSION

This study demonstrates a delayed impact of PAE on growth that manifested around 6 months of age, underscoring the importance of routine clinical monitoring in early childhood. Furthermore, the findings supported prior animal model findings that suggest a mechanistic role for IGF-1 in PAE-induced growth delay.

Impact of low-level prenatal alcohol exposure and maternal stress on autonomic regulation

BACKGROUND

Prenatal alcohol exposure (PAE) impacts the neurodevelopment of the fetus, including the infant's ability to self-regulate. Heart rate variability (HRV), that is, the beat-to-beat variability in heart rate, is a non-invasive measurement that can indicate autonomic nervous system (ANS) function/dysfunction.

METHODS

The study consisted of a subset of our ENRICH-2 cohort: 80 participants (32 PAE and 48 Controls) who had completed three visits during pregnancy. The participants completed a comprehensive assessment of PAE and other substances throughout pregnancy and assessments for stress, anxiety, and depression in the third trimester. At 24 h of age, infant HRV was assessed in the hospital during the clinically indicated heel lance; 3- to 5-min HRV epochs were obtained during baseline, heel lancing, and recovery episodes.

RESULTS

Parameters of HRV differed in infants with PAE compared to Controls during the recovery phase of the heel lance (respiratory sinus arrhythmia (RSA) and high-frequency (HF), p < 0.05). Increased maternal stress was also strongly associated with abnormalities in RSA, HF, and low-frequency / high-frequency (LF/HF, p's < 0.05).

CONCLUSIONS

Alterations in ANS regulation associated with PAE and maternal stress may reflect abnormal development of the hypothalamic-pituitary-adrenal axis and have long term implications for infant responsiveness and self-regulation.

IMPACT

Previous studies have focused on effects of moderate to heavy prenatal alcohol exposure (PAE) on autonomic dysregulation, but little is known about the effects of lower levels of PAE on infant self-regulation and heart rate variability (HRV). Prenatal stress is another risk factor for autonomic dysregulation. Mild PAE impacts infant self-regulation, which can be assessed using HRV. However, the effect of prenatal stress is stronger than that of mild PAE or other mental health variables on autonomic dysregulation.

Predictive risk markers in alcoholism

The medical disorders of alcoholism rank among the leading public health problems worldwide and the need for predictive and prognostic risk markers for assessing alcohol use disorders (AUD) has been widely acknowledged. Early-phase detection of problem drinking and associated tissue toxicity are important prerequisites for timely initiations of appropriate treatments and improving patient's committing to the objective of reducing drinking. Recent advances in clinical chemistry have provided novel approaches for a specific detection of heavy drinking through assays of unique ethanol metabolites, phosphatidylethanol (PEth) or ethyl glucuronide (EtG). Carbohydrate-deficient transferrin (CDT) measurements can be used to indicate severe alcohol problems. Hazardous drinking frequently manifests as heavy episodic drinking or in combinations with other unfavorable lifestyle factors, such as smoking, physical inactivity, poor diet or adiposity, which aggravate the metabolic consequences of alcohol intake in a supra-additive manner. Such interactions are also reflected in multiple disease outcomes and distinct abnormalities in biomarkers of liver function, inflammation and oxidative stress. Use of predictive biomarkers either alone or as part of specifically designed biological algorithms helps to predict both hepatic and extrahepatic morbidity in individuals with such risk factors. Novel approaches for assessing progression of fibrosis, a major determinant of prognosis in AUD, have also been made available. Predictive algorithms based on the combined use of biomarkers and clinical observations may prove to have a major impact on clinical decisions to detect AUD in early pre-symptomatic stages, stratify patients according to their substantially different disease risks and predict individual responses to treatment.

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.

High-resolution imaging in studies of alcohol effect on prenatal development

Fetal alcohol syndrome represents the leading known preventable cause of mental retardation. FAS is on the most severe side of fetal alcohol spectrum disorders that stem from the deleterious effects of prenatal alcohol exposure. Affecting as many as 1 to 5 out of 100 children, FASD most often results in brain abnormalities that extend to structure, function, and cerebral hemodynamics. The present review provides an analysis of high-resolution imaging techniques that are used in animals and human subjects to characterize PAE-driven changes in the developing brain. Variants of magnetic resonance imaging such as magnetic resonance microscopy, magnetic resonance spectroscopy, diffusion tensor imaging, along with positron emission tomography, single-photon emission computed tomography, and photoacoustic imaging, are modalities that are used to study the influence of PAE on brain structure and function. This review briefly describes the aforementioned imaging modalities, the main findings that were obtained using each modality, and touches upon the advantages/disadvantages of each imaging approach.

Assessing the sensitivity and specificity of phosphatidylethanol (PEth) cutoffs to identify alcohol exposed pregnancies

In the literature on alcohol use biomarkers, there has been debate as to what a valid and/or utilitarian cut off level should be for various research applications. In this manuscript, we assessed the sensitivity and specificity of multiple cutoff values for phosphatidylethanol (PEth) from bloodspots relative to self-report, the Alcohol Use Disorder Identification Test (AUDIT) scores, and another alcohol use biomarker ethyl glucuronide (EtG) from fingernails in a sample of 222 pregnant women in the Western Cape Province of South Africa. Receiver operating characteristic (ROC) curves were used to assess the area under the curve (AUC) and assess PEth cutoff values of ≥2, ≥4, ≥8, ≥14, and ≥20 nanograms per milliliter (ng/ml). The highest AUC value was attained when PEth was compared to an AUDIT score of 1 or more. Depending on the cutoff used to determine alcohol consumption, PEth identified 47%-70% of the individuals as alcohol-consuming while 62.6%-75.2% were identified by self-reported measures, and 35.6% were identified by EtG. In this sample, sensitivity and accuracy were highest at less stringent PEth cutoffs when compared to self-report, AUDIT score of 1 or more, 5 or more, 8 or more, and EtG ≥ 8 picograms per milligram (pg/mg). For research purposes, less stringent cutoffs, such as PEth ≥ 8 ng/ml, may be considered a valid, positive cutoff for identifying women who consume alcohol during pregnancy in this population. A cutoff of PEth ≥ 20 ng/ml may miss individuals who reported consuming alcohol (false negatives).

Assessing maternal alcohol consumption in pregnancy: does phosphatidylethanol measured from day 5 newborn blood spot cards have any value? An observational, population-based study

OBJECTIVE

Prenatal alcohol exposure (PAE) places children at risk of fetal alcohol spectrum disorder (FASD) but ascertainment of PAE is problematic. Early intervention for children at risk of FASD may help mitigate long-term difficulties. Phosphatidylethanol (PEth), a metabolite of alcohol, is incorporated into red cell membranes and can be measured in dried blood spot (DBS) cards. In the UK, DBS samples are collected on day 5 for routine newborn screening. We sought to examine if PEth measured from DBS correlates with postnatal maternal self-report of alcohol consumption in pregnancy.

DESIGN

Observational population-based study. Comparison of infant PEth concentration and self-report of maternal alcohol use during pregnancy.

SETTING

Large maternity unit in Glasgow, Scotland.

PARTICIPANTS

All singleton mother-infant dyads delivered during each fourth consecutive 24-hour period.

INTERVENTIONS

Mother: direct, confidential, immediate postnatal interview by a single researcher examining alcohol use during pregnancy. Infant: one extra DBS collected coincident with routine newborn screening if bleeding continued.

RESULTS

92.5% of eligible mothers agreed to participate. 510 DBS were obtained of which 502 were successfully analysed. 216 (43%) samples contained PEth at a concentration of ≥8 ng/mL and 148 (29.5%) at ≥20 ng/mL. The sensitivity of PEth ≥8 ng/mL and ≥20 ng/mL in identifying women who self-reported modest alcohol use after 36 weeks' gestation was 50% and 36.4%, respectively.

CONCLUSION

PEth measured from DBS obtained on day 5 of life does not reliably identify modest PAE after 36 weeks' gestation from maternal self-report.

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.

Prenatal alcohol exposure can be determined from baby teeth: Proof of concept

BACKGROUND

Prenatal alcohol exposure (PAE), leading to fetal alcohol spectrum disorders (FASD), is a serious public health issue in the United States and globally. Diagnosis of FASD is crucial in obtaining appropriate care, but it is not always possible when PAE cannot be documented.

METHODS

Deciduous teeth from a child with known PAE and a child with known absence of PAE were analyzed using liquid chromatography-isotope dilution tandem mass spectrometry (LC-IDMS/MS) in a multiple-reaction monitoring mode for direct markers and LC-high resolution MS in positive and negative mode with hydrophilic interaction liquid chromatography and reverse-phase chromatography, respectively, for indirect markers.

RESULTS

Direct markers of PAE (ethyl glucuronide and ethyl sulfate) were detected in prenatal and postnatal dentine from a case tooth but not from a control tooth. Indirect biomarker analysis indicated a dysregulation of amino acids and an increase in cholesterol sulfate in the case compared to the control tooth.

CONCLUSIONS

This proof-of-concept study demonstrates for the first time that direct biomarkers of PAE are detectable and measurable in deciduous teeth which begin forming in utero and are typically naturally shed between 5 and 12 years of age. Further examination of these novel biomarkers may allow diagnosis of FASD where documentation of PAE is otherwise unavailable. Furthermore, because teeth grow incrementally, defined growth zones can be sampled allowing for identification of gestational timing of PAE to help better understand mechanisms underlying alcohol's disruption of perinatal development.

Prenatal opioid-exposed infant extracellular miRNA signature obtained at birth predicts severity of neonatal opioid withdrawal syndrome

Prenatal opioid exposure (POE) is commonly associated with neonatal opioid withdrawal syndrome (NOWS), which is characterized by a broad variability in symptoms and severity. Currently there are no diagnostic tools to reliably predict which infants will develop severe NOWS, while risk stratification would allow for proactive decisions about appropriate clinical monitoring and interventions. The aim of this prospective cohort study was to assess if extracellular microRNAs (miRNAs) in umbilical cord plasma of infants with POE could predict NOWS severity. Participants (n = 58) consisted of pregnant women receiving medications for opioid use disorder and their infants. NOWS severity was operationalized as the need for pharmacologic treatment and prolonged hospitalization (≥ 14 days). Cord blood miRNAs were assessed using semi-quantitative qRT-PCR arrays. Receiver operating characteristic curves and area under the curve (AUC) were estimated. The expression of three miRNAs (miR-128-3p, miR-30c-5p, miR-421) predicted need for pharmacologic treatment (AUC: 0.85) and prolonged hospitalization (AUC: 0.90). Predictive validity improved after two miRNAs (let-7d-5p, miR-584-5p) were added to the need for pharmacologic treatment model (AUC: 0.94) and another two miRNAs (let-7b-5p, miR-10-5p) to the prolonged hospitalization model (AUC: 0.99). Infant cord blood extracellular miRNAs can proactively identify opioid-exposed neonates at high-risk for developing severe NOWS.

Quantitation of phosphatidylethanols in dried blood spots to determine rates of prenatal alcohol exposure in Ontario

BACKGROUND

Estimating rates of prenatal alcohol exposure (PAE) in a population is necessary to ensure that proper medical and social supports and interventions are in place. This study sought to estimate PAE in Ontario, Canada by quantifying phosphatidylethanol (PEth) homologues in over 2000 residual neonatal dried blood spots (DBS).

METHODS

A random selection of 2011 residual DBS collected over a 1-week time period were anonymized and extracted. A targeted liquid chromatography-mass spectrometry method was used to quantify 1-palmitoyl-2-oleoyl-sn-glycero-3-phosphoethanol (PEth (16:0/18:1) or POPEth), the clinically accepted biomarker, and six additional PEth homologues. A POPEth level above the United States Drug Testing Laboratories (USDTL) cutoff up to 4 weeks predelivery was indicative of PAE. All PEth homologues were correlated to one another and logistic regression was used to determine the association between PAE status and infant characteristics.

RESULTS

The estimated rate of PAE in Ontario, up to the last 4 weeks of gestation, was 15.5% (POPEth >28.5 nM). Most PEth homologues were moderately to strongly correlated to one another. A low birth weight and preterm birth were both associated with PAE, while being small for gestational age had lower odds of PAE.

CONCLUSIONS

The results of this study suggest that PAE may be more prevalent in Ontario than previous estimates by self-report or meconium testing. These findings support the need to consider the effectiveness of current interventions and the design of new interventions to address this significant public health issue.

Using primary teeth and archived dried spots for exposomic studies in children: Exploring new paths in the environmental epidemiology of pediatric cancer

It is estimated that 300,000 children 0-14 years of age are diagnosed with cancer worldwide each year. While the absolute risk of cancer in children is low, it is the leading cause of death due to disease in children in high-income countries. In spite of this, the etiologies of pediatric cancer are largely unknown. Environmental exposures have long been thought to play an etiologic role. However, to date, there are few well-established environmental risk factors for pediatric malignancies, likely due to technical barriers in collecting biological samples prospectively in pediatric populations for direct measurements. In this review, we propose the use of novel or underutilized biospecimens (dried blood spots and teeth) and molecular approaches for exposure assessment (epigenetics, metabolomics, and somatic mutational profiles). Future epidemiologic studies of pediatric cancer should incorporate novel exposure assessment methodologies, data on molecular features of tumors, and a more complete assessment of gene-environment interactions.

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.

Phosphatidylethanol Levels in Postpartum Women and Their Newborns in Uruguay and Brazil

BACKGROUND

There is increasing interest in the development of newborn screening tests to identify children at risk of fetal alcohol spectrum disorder (FASD) in order to provide these children with early intervention. Phosphatidylethanol (PEth) has emerged as a potential universal newborn screening candidate.

METHODS

The aim of this report was to present the results of a study designed to compare PEth levels in 1,140 postpartum women and their newborn infants in Montevideo, Uruguay, and Sao Paulo, Brazil. Self-report alcohol use during pregnancy data was collected, along with both maternal and newborn dried blood spot samples for PEth analysis.

RESULTS

The average age and parity of the women in the sample were 26 years of age and 2.3 pregnancies. For the Uruguay sample (n = 611), 45.8% of postpartum women had PEth levels ≥ 8 ng/ml with a mean positive PEth of 43.6 ng/ml. In contrast, 86.8% of the newborns had PEth levels ≥ 8 ng/ml, with a mean positive PEth of 77.4 ng/ml. For the Brazil sample (n = 529), 33.2% of women had PEth levels ≥ 8 ng/ml with a mean positive PEth of 31 ng/ml. In contrast, 76.9% of the Brazil newborns had PEth levels ≥ 8 ng/ml and 43.9% with a mean positive PEth of 61.1 ng/ml. PEth levels were significantly higher in newborns compared with their postpartum mothers in both the Uruguay and Brazil samples. Self-reported third-trimester alcohol was 6% in the Uruguay sample and 9.1% in the Brazil sample compared with positive maternal PEth levels in 45.8% and 33.2%, respectively.

CONCLUSIONS

Clinicians may want to consider newborn PEth screening in high-risk populations where prenatal alcohol use is common. The mechanism underlying significantly higher PEth levels in newborns compared with their mothers is not known.

CDT reference values for monitoring chronic alcohol abuse in pregnancy

INTRODUCTION AND AIM

Carbohydrate Deficient Transferrin (CDT) is one of the most used biomarkers for monitoring alcohol use in pregnancy. However, its effective application in this context is hampered by the demonstrated physiological progressive increase during pregnancy (even in abstinent women) of CDT values, which in the third trimester can reach values close or exceeding the cut-offs usually adopted in clinical and forensic diagnostics. The present work was aimed at the re-assessment of CDT reference values in pregnancy.

MATERIALS AND METHODS

The CDT analysis was performed by a validated HPLC-UV Vis method on 284 serum samples of women with a physiological pregnancy and on 370 sera of non-pregnant woman from the general population (control group). All the samples were tested also for GGT for excluding alcohol abuse. The statistical analysis was performed using the MedCalc® Statistical Software.

RESULTS

The re-definition of the specific reference concentrations was carried out according to the Horn and Pesce Robust Method. The resulting CDT upper reference values were 1.45%, 2.01% and 2.05% in the first, second, and third trimester, respectively.

CONCLUSIONS

In order to prevent the development of maternal and fetal prenatal alcohol exposure complications, the use of alcohol biomarkers, including CDT, has been proposed. However, this biomarker, in the monitoring of alcohol use in pregnancy, has so far been applied adopting the same cut-off used for general population without taking into consideration the progressive physiological increase of its value throughout the pregnancy. In the present study, a specific re-assessment of the CDT reference concentrations of each trimester is reported.

Multiple Tools Are Needed for the Detection of Prenatal Alcohol Exposure: Findings From a Community Antenatal Setting

BACKGROUND

Although the toxic effects of prenatal alcohol exposure (PAE) on children are well established, there is emerging evidence about the dynamics and associated demographics of drinking patterns across pregnancy, with risky drinking more likely to take place in the period before pregnancy awareness. This study investigated the use of complementary measurement tools in the understanding of alcohol use across pregnancy and reports on the rates and patterns of alcohol use in a community antenatal setting.

METHODS

Data on alcohol consumption before and after awareness of pregnancy were collected via multiple measurement tools: anonymous lifestyle questionnaire, TWEAK (Tolerance, Worried, Eye-opener, Amnesia, K/Cut down) screener questionnaire, and Substance Use Inventory interviews across multiple pregnancy timepoints. Additionally, phosphatidylethanol (PEth), a direct biomarker of alcohol metabolism, collected from newborns' dried blood spot cards, was analyzed.

RESULTS

The TWEAK screener was more likely to identify risky drinking behavior than the lifestyle questionnaire. When pregnancy was unplanned, women were more likely to find out they are pregnant significantly later (p < 0.001) and consume alcohol at moderate-heavy levels (p = 0.03), prolonging the risk to the fetus. There was an association between maternal self-reported alcohol use on the lifestyle questionnaire and Substance Use Inventory interviews, but no association between maternal reports of alcohol use and PEth results (p = 0.72). Women self-reported moderate-heavy alcohol use in early pregnancy only and a positive PEth screen indicated PAE in late pregnancy, suggesting that these methods may identify different groups of women.

CONCLUSIONS

Multiple measurement tools and methods are needed to identify PAE at different points across pregnancy. Prospective sensitive interviewing is better suited to detecting PAE in early pregnancy, but not later when social desirability bias is stronger, and the use of an objective biomarker, such a PEth, may be useful for identifying the risk of PAE in late pregnancy.

Prevalence of alcohol use in late pregnancy

BACKGROUND

Prenatal alcohol exposure (PAE) can result in detrimental developmental complications. The objective of this study was to estimate the most recent PAE prevalence data for the state of West Virginia (WV) and associated factors.

METHOD

In all, 1830 newborn residual dried blood spots (DBS) in the WV Newborn Screening Repository were analyzed for phosphatidylethanol (PETH). Data were matched with Project WATCH data (94% match, N = 1729).

RESULTS

The prevalence of late pregnancy PAE was 8.10% (95%CI: 6.81, 9.38) for all births, 7.61% (95%CI: 6.26, 8.97) for WV residents only, and ranged from 2.27 to 17.11% by region. The significant factors associated with PAE included smoking (OR: 2.03, 95% CI: 1.40, 2.94), preterm births (OR: 1.88; 95% CI: 1.23, 2.89), birth weight of ≤2000 g vs. >3000 g (OR: 2.62, 95%CI: 1.19, 5.79), no exclusive breastfeeding intention (OR: 1.45, 95% CI: 1.02, 2.04), and not exclusively breastfeeding before discharge (OR: 1.61; 95% CI: 1.09, 2.38).

CONCLUSION

The prevalence of PAE is higher than previously shown for the state. Accurate and timely estimates are vital to inform public health workers, policymakers, researchers, and clinicians to develop and promote effective prevention strategies to lower PAE prevalence and provide targeted interventions and treatment services for infants affected by PAE.

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.

The cost-effectiveness of screening tools used in the diagnosis of fetal alcohol spectrum disorder: a modelled analysis

BACKGROUND

Fetal Alcohol Spectrum Disorder (FASD) is characterized by physical and neurological abnormalities resulting from prenatal alcohol exposure. Though diagnosis may help improve patient outcomes, the diagnostic process can be costly. Subsequently, screening children suspected of FASD prior to diagnostic testing has been suggested, to avoid administering testing to children who are unlikely to receive a diagnosis. The present study set out to assess the cost-effectiveness of currently recommended FASD screening tools.

METHODS

The screenings tools evaluated were chosen from Children's Healthcare Canada's National Screening Toolkit for Children and Youth Identified and Potentially Affected by FASD and include meconium testing of fatty acid ethyl esters (meconium testing) and the neurobehavioral screening tool (NST). An economic model was constructed to assess cost-effectiveness. One-way and probabilistic sensitivity analyses were conducted to assess the robustness of findings. Costs reflect 2017 Canadian dollars and the perspective is the public healthcare system.

RESULTS

Both screening tools evaluated resulted in reduced costs and fewer diagnosed years of life than a no screening strategy in which all children suspected of FASD receive diagnostic testing. The model predicts that screening newborns with meconium testing results in a reduced cost of $89,186 per 100 individuals screened and 38 fewer diagnosed years of life by age 18, corresponding to an incremental cost-effectiveness ratio (ICER) of $2359. Screening children with the NST resulted in a reduced cost of $183,895 per 100 individuals screened and 77 fewer diagnosed years of life by age 18, corresponding to an ICER of $2390.

CONCLUSION

Findings suggest that screening is associated with less use of healthcare recourses but also fewer years of life with an FASD diagnosis over a no screening strategy. Since diagnosis can be key to children receiving timely and appropriate health and educational services, cost-savings must be weighed against the fewer years of life with a diagnosis associated with screening.

Should phosphatidylethanol be currently analysed using whole blood, dried blood spots or both?

Phosphatidylethanol (PEth) are phospholipids produced through non-oxidative ethanol metabolism. They accumulate in red blood cells and have been traditionally analysed in whole blood as potential biomarkers for moderate to long-term alcohol consumption. More recently, their analysis in dried blood spots has been gaining favour, namely, due to the ease in sampling, transport and storage conditions required. This paper aims at providing a short comparative review between analysing PEth in whole blood and dried blood spots and the potential pitfalls that researchers may face when setting up PEth testing for clinical use.

Screening for prenatal alcohol exposure and corresponding short-term neonatal outcomes

Detection of prenatal alcohol exposure (PAE) is important for early intervention and treatment. The main purpose of this study was to compare 1.) PAE rates using the biomarker, phosphatidylethanol (PEth), in umbilical cord (UC) blood vs. ethyl glucuronide (EtG) in UC tissue, the standard of care, and 2.) Pregnancy characteristics and neonatal outcomes in newborns positive vs. negative for PAE biomarkers. We examined records of neonates born over a two-year span receiving UC-PEth dried blood spots testing at the time of delivery in addition to standard of care PAE screening (n = 146). UC-PEth testing had a higher PAE detection rate (26%) vs. UC tissue EtG (0%, p < 0.01). PAE was not associated with any neonatal dysmorphic features or short-term adverse outcomes. The absence of significant clinical findings for identifying PAE in neonates reinforces alcohol biomarker necessity. We conclude that UC-PEth may be a valuable test for assessing PAE at birth and in identifying infants at risk for developing fetal alcohol spectrum disorder.

Determination of phosphatidylethanol 16:0/18:1 in whole blood by 96-well supported liquid extraction and UHPLC-MS/MS

BACKGROUND

Phosphatidylethanols (PEths) are specific, direct alcohol biomarkers that can be determined in human blood to distinguish between heavy and social drinking. PEth 16:0/18:1 is among the most predominant PEth homologues in human blood. The aim of the study was to develop a high throughput and sensitive UHPLC-MS/MS method for the determination of PEth 16:0/18:1 in whole blood.

METHODS

Whole blood samples were prepared by 96-well supported liquid extraction (SLE). Extracted samples were analyzed for PEth 16:0/18:1 by reversed phase UHPLC-MS/MS.

RESULTS

The developed UHPLC-MS/MS method was fully validated in whole blood with PEth 16:0/18:1-D₅ as internal standard. Intermediate precision and intermediate accuracy were within ≤± 12% and ≤± 17%, respectively, at PEth 16:0/18:1 concentrations of 1.4-2112 ng/mL (2.0-3004 nmol/L). Limit of quantification (LOQ) was 1.7 ng/mL (2.4 nmol/L).

CONCLUSION

For the first time, 96-well SLE was used for preparation of a PEth homologue in biological samples. A mixture of tert-butyl methyl ether and 2-propanol (5:1, v:v) was chosen as organic eluent based on an evaluation of extraction recovery, purity of extracts, and evaporation time. The developed UHPLC-MS/MS method can be used for high throughput analyses and sensitive determinations of PEth 16:0/18:1 in whole blood.

Fetal Cerebral Circulation as Target of Maternal Alcohol Consumption

Alcohol (ethanol [EtOH]) is one of the most widely used psychoactive substances worldwide. Alcohol consumption during pregnancy may result in a wide range of morphological and neurodevelopmental abnormalities termed fetal alcohol spectrum disorders (FASD), with the most severe cases diagnosed as fetal alcohol syndrome (FAS). FAS and FASD are not readily curable and currently represent the leading preventable causes of birth defect and neurodevelopmental delay in the United States. The etiology of FAS/FASD remains poorly understood. This review focuses on the effects of prenatal alcohol exposure (PAE) on fetal cerebrovascular function. A brief introduction to the epidemiology of alcohol consumption and the developmental characteristics of fetal cerebral circulation is followed by several sections that discuss current evidence documenting alcohol-driven alterations of fetal cerebral blood flow, artery function, and microvessel networks. The material offers mechanistic insights at the vascular level itself into the pathophysiology of PAE.

Challenges of diagnosing fetal alcohol spectrum disorders in foster and adopted children

Fetal Alcohol Spectrum Disorders (FASD) might be 10-15 times more prevalent among foster/adopted children compared to the general population; however, many of these children remain undiagnosed or misdiagnosed. The lack of confirmed prenatal alcohol exposure (PAE) may be a key barrier to diagnosis. Our sample included 681 patients evaluated for FASD, according to the University of Washington 4-Digit Diagnostic Code, at a pediatric specialty clinic. Guardianship status and other patient characteristics were evaluated by multinomial logistic regression as potential predictors of being classified into one of the following FASD groups: 1) full or partial Fetal Alcohol Syndrome (FAS/pFAS; n = 97); 2) Static Encephalopathy/Alcohol-Exposed (SE/AE) or Neurobehavioral Disorder/Alcohol-Exposed (ND/AE) (n = 135); and 3) some features of FASD (equivalent to pFAS, SE/AE or ND/AE phenotypes) but unknown PAE (n = 449). Median age at assessment was 7.0 years, non-Hispanic White constituted the predominant racial/ethnic group (49.5%), and the majority (81.8%) lacked involvement from a biological parent/relative. Many patients (66.0%) had some features of FASD but lacked reliable PAE information. Children classified into the 'some features/unknown PAE' group had higher median age of assessment (8 years) compared to other groups (6 years; p < 0.001). No association was observed between race/ethnicity or child's sex and FASD outcomes (p > 0.05). Adopted/foster children were 2.8 times as likely (95% CI: 1.6; 4.8) to be classified into the 'some features/unknown PAE' group compared to children living with a parent/relative after adjusting for covariates. This study's findings indicate that adopted/foster children are more likely to have unknown PAE and not receive a FASD diagnosis, potentially denying them access to specialized services, treatment, and rehabilitation.

A utilitarian comparison of two alcohol use biomarkers with self-reported drinking history collected in antenatal clinics

BACKGROUND

Alcohol use is reported accurately among pregnant women in some populations.

METHODS

Self-reported alcohol use via the AUDIT and 90-day recall for 193 women from antenatal clinics was compared to biomarker results: phosphatidylethanol (PEth) from bloodspots and ethyl glucuronide (EtG) in fingernails.

RESULTS

AUDIT was positive for 67.9% of respondents, and 65.3% directly reported drinking. Individual biomarkers detected less drinking (PEth = 57.0%, EtG = 38.9%) than self-report. But 64.8% had drinking-positive values (>8 ng) on one or both biomarkers, which was not significantly different from self-report. Biomarkers indicated that 3.1% -6.8% of drinkers denied drinking. Combined biomarker sensitivity was 95% -80% and specificity 49% -76% for drinking in the previous 7-90 days. Combined biomarker results have their best yield (89.6%) and accuracy (78.8%) when measuring 90 day drinking.

CONCLUSIONS

Women reported their alcohol use accurately, and the combined use of PEth and EtG is supported.

Prevalence of Fetal Alcohol Spectrum Disorders in 4 US Communities

IMPORTANCE

Fetal alcohol spectrum disorders are costly, life-long disabilities. Older data suggested the prevalence of the disorder in the United States was 10 per 1000 children; however, there are few current estimates based on larger, diverse US population samples.

OBJECTIVE

To estimate the prevalence of fetal alcohol spectrum disorders, including fetal alcohol syndrome, partial fetal alcohol syndrome, and alcohol-related neurodevelopmental disorder, in 4 regions of the United States.

DESIGN, SETTING, AND PARTICIPANTS

Active case ascertainment methods using a cross-sectional design were used to assess children for fetal alcohol spectrum disorders between 2010 and 2016. Children were systematically assessed in the 4 domains that contribute to the fetal alcohol spectrum disorder continuum: dysmorphic features, physical growth, neurobehavioral development, and prenatal alcohol exposure. The settings were 4 communities in the Rocky Mountain, Midwestern, Southeastern, and Pacific Southwestern regions of the United States. First-grade children and their parents or guardians were enrolled.

EXPOSURES

Alcohol consumption during pregnancy.

MAIN OUTCOMES AND MEASURES

Prevalence of fetal alcohol spectrum disorders in the 4 communities was the main outcome. Conservative estimates for the prevalence of the disorder and 95% CIs were calculated using the eligible first-grade population as the denominator. Weighted prevalences and 95% CIs were also estimated, accounting for the sampling schemes and using data restricted to children who received a full evaluation.

RESULTS

A total of 6639 children were selected for participation from a population of 13 146 first-graders (boys, 51.9%; mean age, 6.7 years [SD, 0.41] and white maternal race, 79.3%). A total of 222 cases of fetal alcohol spectrum disorders were identified. The conservative prevalence estimates for fetal alcohol spectrum disorders ranged from 11.3 (95% CI, 7.8-15.8) to 50.0 (95% CI, 39.9-61.7) per 1000 children. The weighted prevalence estimates for fetal alcohol spectrum disorders ranged from 31.1 (95% CI, 16.1-54.0) to 98.5 (95% CI, 57.5-139.5) per 1000 children.

CONCLUSIONS AND RELEVANCE

Estimated prevalence of fetal alcohol spectrum disorders among first-graders in 4 US communities ranged from 1.1% to 5.0% using a conservative approach. These findings may represent more accurate US prevalence estimates than previous studies but may not be generalizable to all communities.

Phosphatidylethanol Levels Among Incarcerated Women: The Influence of Pre-incarceration Alcohol Consumption and Length of Abstinence

BACKGROUND

Phosphatidylethanol (PEth) is a direct biomarker for alcohol that is formed shortly after alcohol use and may remain detectable in blood for weeks after alcohol consumption. There is little research on alcohol use factors that influence PEth elimination, especially among women.

METHODS

Data were collected from 116 alcohol use-disordered women who were recently incarcerated. We used a 2-part model with logistic and linear components to examine whether alcohol consumption in the 2 weeks prior to incarceration and days since last alcoholic drink (operationalized as abstinence days prior to incarceration + days incarcerated) were associated with PEth detectability (>8 ng/ml) and level (ng/ml) in blood.

RESULTS

Participants reported drinking an average of 10 drinks per day in the 2 weeks prior to incarceration. Days since last drink was negatively associated with PEth level (odds ratio [OR] = 0.97, 95% confidence interval [CI] = 0.93; 0.99) and being PEth detectable (OR = 0.96, 95% CI = 0.91; 0.99). Quantity of alcohol consumed prior to jail admission was associated with PEth detection (OR = 1.08; 95% CI = 1.03; 1.16), but not PEth level.

CONCLUSIONS

Days since last alcoholic drink and drinks per day both influenced PEth detectability, but only days since last drink predicted PEth level among a large sample of women with alcohol use disorder in the criminal justice system.

Dietary Intake Among Opioid- and Alcohol-Using Pregnant Women

BACKGROUND

Substance abuse in nonpregnant adults has been associated with increased intake in calories and decreased intake of nutrient-dense foods; however, studies examining dietary intake in opioid-using and alcohol-using pregnant women are lacking.

OBJECTIVE

The objective of this study was to evaluate dietary intake in opioid-using pregnant women with or without concurrent light-to-moderate alcohol use as compared to abstaining controls.

METHODS

This prospective birth cohort included 102 pregnant women classified into four study groups: controls (n = 27), medication-assisted treatment (MAT; n = 26), alcohol (ALC; n = 22), and concurrent use of both substances (MAT + ALC; n = 27). Percentage differences in macro- and micronutrient intake were estimated from the food frequency questionnaire and compared among the study groups. Proportions of participants with intakes below the estimated average requirements (EAR) based on diet and diet with supplements were estimated.

RESULTS

Three exposed groups had lower prevalence of multivitamin use in periconceptional period (11.5-31.8%) than controls (44.4%). Unadjusted mean energy intake was significantly higher in the MAT + ALC group compared to controls, while micronutrient intake per 1000 kcal was the highest in the control group for almost all of the micronutrients analyzed. After adjustment for energy intake and sociodemographic characteristics, MAT group had lower estimated dietary intake of iron (-15.0%, p = 0.04) and folate (-16.8%, p = 0.04) compared to controls. A high proportion of participants in all study groups had dietary intake below the EAR for vitamin E, iron, and folate.

CONCLUSION

Results highlight the need for targeted dietary interventions for opioid-using pregnant women.

A survey of attitudes, beliefs and practice regarding alcohol use and screening in pregnancy: an opportunity for support and education?

Providing antenatal and postnatal support for women who drink alcohol in pregnancy is only possible if those at risk can be identified. However, screening will only be helpful if women feel comfortable with the method used. We conducted a survey of pregnant women and their partners to investigate self-reported beliefs and practice regarding drinking during pregnancy and the acceptability of screening. Pregnant women and their partners attending antenatal clinics in North-East England were asked to complete a short survey regarding their alcohol consumption in pregnancy, their beliefs about safe levels of alcohol in pregnancy and whether they would be happy to have their blood or their baby’s meconium analysed for alcohol biomarkers. The data were summarised using descriptive statistics and thematic analysis. A total of 171 pregnant women and 41 partners participated. Of the pregnant women, 153 (89.5%) felt women should abstain from alcohol consumption, although only 70 (40.9%) reported not drinking in pregnancy. Of 96 women who reported drinking in pregnancy and reported when they stopped, all but six (6.3%) stopped drinking when they found out they were pregnant. Of women and partners who recorded an answer, 177 (87.2%) said they would consent to blood biomarker analysis. Confusion over what level of alcohol is safe and using screening as an opportunity for education and support emerged as key themes from free-text responses. Most women viewed screening for alcohol in pregnancy positively, although its acceptability in the small number of women who continue to drink is unclear.

The effect of prenatal substance use and maternal contingent responsiveness on infant affect

BACKGROUND

The effects of prenatal substance exposure on neurobehavioral outcomes are inherently confounded by the effects of the postnatal environment, making it difficult to disentangle their influence. The goal of this study was to examine the contributing effects of prenatal substance use and parenting style (operationalized as contingent responding during the play episodes of the Still-face paradigm [SFP]) on infant affect.

METHODS

A prospective cohort design was utilized with repeated assessment of substance use during pregnancy and the administration of the SFP, which measures infant response to a social stressor, at approximately 6months of age. Subjects included 91 dyads classified into four groups: 1) Control (n=34); 2) Medication assisted therapy for opioid dependence (MAT; n=19); 3) Alcohol (n=15); 4) Alcohol+MAT (n=23). Mean % of positive infant affect and mean % of maternal responsiveness (watching, attention seeking, and contingent responding) was compared among the five SFP episodes across the four study groups by MANOVA. Mixed effects modelling was used to estimate the contributing effects of the study groups and maternal responsiveness on infant affect.

RESULTS

Maternal contingent responding was associated with increase (β̂=0.84; p<0.0001) and attention seeking with decrease (β̂=-0.78; p<0.0001) in infant positive affect. The combined effect of prenatal exposures and covariates explained 15.8% of the variability in infant positive affect, while the model including contingent responding and covariates explained 67.1% of the variability.

CONCLUSIONS

Higher maternal responsiveness was a much stronger predictor of infant behavior than prenatal exposures, providing the basis for future intervention studies focusing on specific parenting strategies.

Do Subjective Alcohol Screening Tools Correlate with Biomarkers Among High-Risk Transgender Women and Men Who Have Sex with Men in Lima, Peru?

Alcohol abuse can influence sexual risk behavior; however, its measurement is not straightforward. This study compared self-reported alcohol use, via the AUDIT and CAGE, with levels of phosphatidylethanol (Peth), a phospholipid biomarker that forms with chronic, heavy drinking, among high-risk MSM and TW in Lima, Peru. Chi square, Fisher's exact, Wilcoxon ranksum tests compared the instruments. Receiver operating curves determined sensitivity and specificity of the self-reported measures. Among 69 MSM and 17 TW, PEth was positive for 86% (95% CI 77-93%) of participants, while 67% reported binge-drinking in the last 2 weeks. The AUDIT classified 25% as hazardous drinkers while CAGE identified 6% as problem drinkers. Self-reported binge drinking was more sensitive than the AUDIT for PEth positivity (71% vs. 27%, p = 0.022). Among high-risk MSM and TW in Lima, validated, self-report measures of alcohol abuse underestimated biological measures. Further research correlating bio-markers and self-reported alcohol abuse measures is needed.

Cut-Point Levels of Phosphatidylethanol to Identify Alcohol Misuse in a Mixed Cohort Including Critically Ill Patients

BACKGROUND

Although alcohol misuse is associated with deleterious outcomes in critically ill patients, its detection by either self-report or examination of biomarkers is difficult to obtain consistently. Phosphatidylethanol (PEth) is a direct alcohol biomarker that can characterize alcohol consumption patterns; however, its diagnostic accuracy in identifying misuse in critically ill patients is unknown.

METHODS

PEth values were obtained in a mixed cohort comprising 122 individuals from medical and burn intensive care units (n = 33), alcohol detoxification unit (n = 51), and healthy volunteers (n = 38). Any alcohol misuse and severe misuse were referenced by Alcohol Use Disorders Identification Test (AUDIT) and AUDIT-C scores separately. Mixed-effects logistic regression analysis was performed, and the discrimination of PEth was evaluated using the area under the receiver-operating characteristic (ROC) curve.

RESULTS

The area under the ROC curve for PEth was 0.927 (95% CI: 0.877, 0.977) for any misuse and 0.906 (95% CI: 0.850, 0.962) for severe misuse defined by AUDIT. By AUDIT-C, the area under the ROC curves was 0.948 (95% CI: 0.910, 0.956) for any misuse and 0.913 (95% CI: 0.856, 0.971) for severe misuse. The PEth cut-points of ≥250 and ≥400 ng/ml provided optimal discrimination for any misuse and severe misuse, respectively. The positive predictive value for ≥250 ng/ml was 88.7% (95% CI: 77.5, 95.0), and the negative predictive value was 86.7% (95% CI: 74.9, 93.7). PEth ≥ 400 ng/ml achieved similar values, and similar results were shown for AUDIT-C. In a subgroup analysis of critically ill patients only, test characteristics were similar to the mixed cohort.

CONCLUSIONS

PEth is a strong predictor and has good discrimination for any and severe alcohol misuse in a mixed cohort that includes critically ill patients. Cut-points at 250 ng/ml for any, and 400 ng/ml for severe, are favorable. External validation will be required to establish these cut-points in critically ill patients.

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.

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.

In utero alcohol effects on foetal, neonatal and childhood lung disease

Maternal alcohol use during pregnancy exposes both premature and term newborns to the toxicity of alcohol and its metabolites. Foetal alcohol exposure adversely effects the lung. In contrast to the adult "alcoholic lung" phenotype, an inability to identify the newborn exposed to alcohol in utero has limited our understanding of its effect on adverse pulmonary outcomes. This paper will review advances in biomarker development of in utero alcohol exposure. We will highlight the current understanding of in utero alcohol's toxicity to the developing lung and immune defense. Finally, we will present recent clinical evidence describing foetal alcohol's association with adverse pulmonary outcomes including bronchopulmonary dysplasia, viral infections such as respiratory syncytial virus and allergic asthma/atopy. With research to define alcohol's effect on the lung and translational studies accurately identifying the exposed offspring, the full extent of alcohol's effects on clinical respiratory outcomes of the newborn or child can be determined.

Alcohol Use During Pregnancy is Associated with Specific Alterations in MicroRNA Levels in Maternal Serum

Background

Given the challenges of confirming prenatal alcohol exposure (PAE) during pregnancy using currently established biomarkers of alcohol consumption, we examined whether serum microRNAs (miRNAs) may serve as stable biomarkers for PAE. Alterations in the levels of specific circulating miRNAs have been associated with various disease states and in animal models of fetal alcohol spectrum disorder.

Methods

Pregnant women in this prospective study were recruited from substance abuse and general maternity clinics affiliated with the University of New Mexico. Serum was collected at the time of admission for delivery from 14 subjects who reported ≥1 binge‐drinking episode or ≥3 drinks/wk during pregnancy and 16 subjects who reported abstinence during pregnancy and tested negative for 5 ethanol biomarkers. Total RNA was isolated from serum and used for microarray analysis.

Results

False discovery rate‐corrected analyses of covariance revealed that 55 miRNAs were significantly altered between the 2 groups. Hierarchical clustering using only the significantly altered miRNAs grouped samples into alcohol‐consuming and non‐alcohol‐consuming individuals. Discriminant analysis then identified miRs‐122*, ‐126, ‐216b, ‐221*, ‐3119, ‐3942‐5p, ‐4704‐3p, ‐4743, ‐514‐5p, and ‐602 as the top 10 discriminators between the 2 groups. Ingenuity Pathway Analysis of putative miRNA targets illustrated that miRNAs identified in this study are involved in biological pathways that mediate the effects of alcohol, such as brain‐derived neurotrophic factor, ERK1/2, and PI3K/AKT signaling.

Conclusions

This is the first report of alterations in serum miRNA expression that are associated with alcohol use during human pregnancy. These results suggest that serum miRNAs could be useful as biomarkers of alcohol exposure.

Second-Trimester Ultrasound as a Tool for Early Detection of Fetal Alcohol Spectrum Disorders

BACKGROUND

Early detection of fetal alcohol spectrum disorders (FASDs) is desirable to allow earlier and more comprehensive interventions to be initiated for the mother and infant. We examined prenatal ultrasound as an early method of detecting markers of the physical features and neurobehavioral deficits characteristic of FASD.

METHODS

A longitudinal cohort of pregnant women in Ukraine was recruited as part of the Collaborative Initiative on Fetal Alcohol Spectrum Disorders. Women were enrolled into a moderately to heavy-alcohol-exposed group or a low- or no-alcohol exposure group and were followed to pregnancy outcome. In the second trimester, a fetal ultrasound was performed to measure transverse cerebellar diameter, occipital frontal diameter (OFD), caval-calvarial distance, frontothalamic distance (FTD), interorbital distance (IOD), outer orbital diameter, and orbital diameter (OD). Live born infants received a dysmorphological examination and a neurobehavioral evaluation using the Bayley Scales of Infant Development. These data were used to classify infants with respect to FASD. Comparisons were made on the ultrasound measures between those with and without features of FASD, adjusting for gestational age at ultrasound and maternal smoking.

RESULTS

A total of 233 mother/child dyads were included. Children classified as FASD had significantly longer IOD and lower FTD/IOD, OFD/IOD, and FTD/OD ratios (p < 0.05). Children with a Bayley score <85 had significantly shorter FTD, longer IOD, lower OFD/IOD, and FTD/IOD ratios (p < 0.05). In general, mean differences were small. Ultrasound variables alone predicted <10% of the variance in the FASD outcome.

CONCLUSIONS

Some ultrasound measurements were associated with FASD, selected facial features of the disorder, and lower neurobehavioral scores. However, mean differences were relatively small, making it difficult to predict affected children based solely on these measures. It may be advantageous to combine these easily obtained ultrasound measures with other data to aid in identifying high risk for an FASD outcome.

Assays of Gamma-Glutamyl Transferase and Carbohydrate-Deficient Transferrin Combination from Maternal Serum Improve the Detection of Prenatal Alcohol Exposure

BACKGROUND

Alcohol use during pregnancy leads to detrimental effects on fetal development. As self-reports by mothers are known to be unreliable for assessing prenatal alcohol exposure, there is a need for sensitive and specific biomarkers for identifying those at risk for alcohol-affected offspring.

METHODS

We measured serum gamma-glutamyl transferase (GGT), carbohydrate-deficient transferrin (CDT), a mathematically formulated combination of GGT and CDT (GGT-CDT), and ethylglucuronide (EtG) concentrations from 1,936 mothers with a positive (n = 480) or negative (n = 1,456) history of alcohol use at the time of pregnancy. The material included 385 alcohol-abusing mothers who subsequently gave birth to children with fetal alcohol syndrome (FAS) and 1,551 mothers without FAS children including 95 women who reported a median of 1.0 standard drinks of alcohol per day during pregnancy and 1,456 nondrinking controls. Among those without FAS outcome, there were 405 mothers with gestational diabetes mellitus (GDM) and 745 mothers representing lifelong abstainers.

RESULTS

Mothers of FAS children had higher mean GGT, CDT, GGT-CDT, and EtG levels than abstainers (p < 0.001 for all comparisons) or mothers reporting some alcohol consumption but whose children were not diagnosed with FAS (p < 0.001 for all comparisons). In receiver operating characteristic analyses using cutoffs based on abstainers, the area under the curves (AUCs) for GGT-CDT (0.873) were higher than those of GGT (0.824), CDT (0.776), or EtG (0.584) for differentiating the mothers of FAS children and abstainers. Unlike CDT, this combination marker also differed significantly between drinking mothers without FAS outcome and abstainers (AUC = 0.730, p < 0.001). In comparisons adjusted for GDM and body mass index, the group of mothers who had reported a median of 1.0 standard drinks of alcohol per day during pregnancy also differed from the group reporting no current alcohol intake in GGT (p < 0.02) and GGT-CDT (p < 0.01) levels.

CONCLUSIONS

Combination of GGT and CDT improves the identification of prenatal alcohol exposure and associated high-risk pregnancies. A more systematic use of biomarkers may help intervention efforts to prevent alcohol-induced adverse effects on fetal development.

Validity of Self-Reported Drug Use Information Among Pregnant Women

INTRODUCTION

This study assesses validity of self-report for the use of major classes of illicit drugs and opioid-maintenance therapy among pregnant women at a substance abuse treatment program.

METHODS

Analyses used data collected from 83 pregnant women in a prospective cohort study at the University of New Mexico. Study participants with a history of substance abuse were screened and, if eligible, enrolled during an early prenatal care visit. A follow-up interview was conducted shortly after delivery. Self-reported information about drug use later in pregnancy was compared with urine drug screen (UDS) results collected during the third trimester. Simple kappa (k) and prevalence-and-bias-adjusted kappa (PABAK) coefficients were calculated as the measures of agreement. Sensitivity and specificity of self-report for each drug class were estimated using UDS as the 'gold standard'.

RESULTS

The sample included a large proportion of ethnic minority (80% Hispanic/Latina and 7% American Indian) and socially disadvantaged (50% less than high school education and 94% Medicaid-insured) pregnant women. On average, patients had 4.8 ± 3.0 urine drug screens during the third trimester. Sensitivity of self-report was low (<60%) for all classes of illicit drugs; however, marijuana and opioids demonstrated slightly higher sensitivity (57.9 and 58.3%, respectively) than other classes (<47%).

CONCLUSIONS

This study found substantial underreporting for all classes of illicit drugs among pregnant women in a substance abuse treatment program. Rates of underreporting are expected to be higher among the general population of pregnant women.

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.

Fetal alcohol-spectrum disorders: identifying at-risk mothers

Fetal alcohol-spectrum disorders (FASDs) are a collection of physical and neurobehavioral disabilities caused by prenatal exposure to alcohol. To prevent or mitigate the costly effects of FASD, we must identify mothers at risk for having a child with FASD, so that we may reach them with interventions. Identifying mothers at risk is beneficial at all time points, whether prior to pregnancy, during pregnancy, or following the birth of the child. In this review, three approaches to identifying mothers at risk are explored: using characteristics of the mother and her pregnancy, using laboratory biomarkers, and using self-report assessment of alcohol-consumption risk. At present, all approaches have serious limitations. Research is needed to improve the sensitivity and specificity of biomarkers and screening instruments, and to link them to outcomes as opposed to exposure. Universal self-report screening of all women of childbearing potential should ideally be incorporated into routine obstetric and gynecologic care, followed by brief interventions, including education and personalized feedback for all who consume alcohol, and referral to treatment as indicated. Effective biomarkers or combinations of biomarkers may be used during pregnancy and at birth to determine maternal and fetal alcohol exposure. The combination of self-report and biomarker screening may help identify a greater proportion of women at risk for having a child with FASD, allowing them to access information and treatment, and empowering them to make decisions that benefit their children.

Alternative sampling strategies for the assessment of alcohol intake of living persons

Monitoring of alcohol consumption by living persons takes place in various contexts, amongst which workplace drug testing, driving under the influence of alcohol, driving licence regranting programs, alcohol withdrawal treatment, diagnosis of acute intoxication or fetal alcohol ingestion. The matrices that are mostly used today include blood, breath and urine. The aim of this review is to present alternative sampling strategies that allow monitoring of the alcohol consumption in living subjects. Ethanol itself, indirect (carbohydrate deficient transferrin, CDT%) as well as direct biomarkers (ethyl glucuronide, EtG; ethyl sulphate, EtS; fatty acid ethyl esters, FAEEs and phosphatidylethanol species, PEths) of ethanol consumption will be considered. This review covers dried blood spots (CDT%, EtG/EtS, PEths), dried urine spots (EtG/EtS), sweat and skin surface lipids (ethanol, EtG, FAEEs), oral fluid (ethanol, EtG), exhaled breath (PEths), hair (EtG, FAEEs), nail (EtG), meconium (EtG/EtS, FAEEs), umbilical cord and placenta (EtG/EtS and PEth 16:0/18:1). Main results, issues and considerations specific to each matrix are reported. Details about sample preparation and analytical methods are not within the scope of this review.

Quantification of phosphatidylethanol 16:0/18:1, 18:1/18:1, and 16:0/16:0 in venous blood and venous and capillary dried blood spots from patients in alcohol withdrawal and control volunteers

Phosphatidylethanol species (PEths) are promising biomarkers of alcohol consumption. Here, we report on the set-up, validation, and application of a novel UHPLC-ESI-MS/MS method for the quantification of PEth 16:0/18:1, PEth 18:1/18:1, and PEth 16:0/16:0 in whole blood (30 μL) and in venous (V, 30 μL) or capillary (C, 3 punches (3 mm)) dried blood spots (DBS). The methods were linear from 10 (LLOQ) to 2000 ng/mL for PEth 16:0/18:1, from 10 (LLOQ) to 1940 ng/mL for PEth 18:1/18:1, and from 19 (LLOQ) to 3872 ng/mL for PEth 16:0/16:0. Extraction efficiencies were higher than 55% (RSD < 18%) and matrix effects compensated for by IS were between 77 and 125% (RSD < 10%). Accuracy, repeatability, and intermediate precision fulfilled acceptance criteria (bias and RSD below 13%). Validity of the procedure for determination of PEth 16:0/18:1 in blood was demonstrated by the successful participation in a proficiency test. The quantification of PEths in C-DBS was not significantly influenced by the hematocrit, punch localization, or spot volume. The stability of PEths in V-DBS stored at room temperature was demonstrated up to 6 months. The method was applied to authentic samples (whole blood, V-DBS, and C-DBS) from 50 inpatients in alcohol withdrawal and 50 control volunteers. Applying a cut-off value to detect inpatients at 221 ng/mL for PEth 16:0/18:1 provided no false positive results and a good sensitivity (86%). Comparison of quantitative results (Bland-Altman plot, Passing-Bablok regression, and Wilcoxon signed rank test) revealed that V-DBS and C-DBS were valid alternatives to venous blood for the detection of alcohol consumption.

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.