The Increased Sensitivity of Phosphatidylethanol Over Fatty Acid Ethyl Esters in Identifying Neonates Exposed to Dangerous Levels of Alcohol In Utero

A. Baldwin, M. Jones, R. Magri, J. Jones, C. Plate, D. Lewis

Significance• Despite initiatives to increase awareness, alcohol consumption during

pregnancy continues to be a serious public health concern in manycountries.

• Cultural patterns of drinking alcohol in Uruguay have changed in thelast 30 years, from moderate consumption with meals to more risky,dangerous patterns of heavy alcohol consumption.

• Data from a surveillance study conducted in Uruguay in 2007 foundthat 65.6% of women surveyed reported alcohol use duringpregnancy (1).

• The incidence of prenatal alcohol exposure in Montevido, Uruguay,as determined by fatty acid ethyl esters (FAEE) detection inmeconium, was found to be 44% (2).

• Maternal self-report questionnaires and detection of FAEE inmeconium are currently standard tests for identifying alcohol-exposed neonates but we have found a significant number ofalcohol-exposed newborns can be missed by these methods.

• Phosphatidylethanol (PEth) is a direct biomarker of alcoholmetabolism that has been shown to be an indicator of high,sustained levels of alcohol intake, at levels that would put a fetus athigh risk for potential alcohol-induced birth defects.

• Detection of PEth in dried blood spot (DBS) cards from routineneonatal heel sticks has been shown to be a feasible and costeffective method to screen for prenatal alcohol exposure (3).

Research Aims• Assess the presence of FAEEs in meconium and PEth in DBS cards of

neonates from a high risk population of mothers.

• Evaluate the usage of self-reported drinking assessments and thedirect alcohol biomarkers FAEE and PEth in newborns to comparetheir utility in identifying prenatal alcohol exposure.

Experimental Design• Pregnant women considered at high risk for prenatal alcohol

exposure, who delivered at the Neonatologist University School at theNational Social Security Perinatology Unit in Montevideo, Uruguay,were enrolled in the study by Dr. Raquel Magri, Assessor in Alcoholand Drugs for this hospital.

• Of the 232 mothers enrolled, 135 subjects had:• Complete maternal self-report data• Complete newborn birth characteristics data• Sufficient meconium for FAEE analysis• DBS cards for PEth analysis.

• Evaluate the number of infants positive for FAEE in meconium and/orpositive for PEth in DBS.

• Identify mothers that self-report drinking during pregnancy andcompare the positive rates for FAEE in meconium and PEth in DBS inthis population of infants with known prenatal alcohol exposure.

Results

Figure 1. Sensitivity of newborn alcohol biomarkers based on the percentage of mothers who self-report alcohol use during pregnancy.

Conclusions

Variable Mean ± SDGestational age (weeks) 38.4 ± 1.5Birth weight (grams) 3277 ± 481Birth length (cm) 48.9 ± 2.1Birth head circumference (cm) 34.4 ± 1.4Apgar score 8.9 ± 0.7Females 69 (51.1%)Premature (<37 weeks gestation) 15 (11.1%)

Table II. Newborn Characteristics

VariableAge at birth (years) 24.7 ± 5.5Education (years) 8.8 ± 2.3Married 31 (23.0%)Employed 14 (10.4%)Low socioeconomic status 118 (87.4%)Reported any alcohol use during pregnancy 81 (60.0%)Reported smoking during pregnancy 53 (39.3%)Reported marijuana use during pregnancy 0 (0.0%)Reported cocaine use during pregnancy 0 (0.0%)

Table I. Maternal Characteristics (135 subjects)

• Detection of PEth in DBS cards identified newborns exposed to alcohol in uteroat a higher rate than detection of FAEE in meconium.

• The positive rate of PEth detection in DBS cards was higher than detection ofFAEE in meconium for all maternal alcohol consumption timeframes andfrequencies during pregnancy.

• Detection of PEth in newborns of mothers who report drinking only during thefirst 3 months suggests that these mothers in fact drank throughout pregnancyand PEth detects a higher rate of these at-risk mothers.

• The advantage of PEth analysis over current biomarkers is that:• Analysis of PEth in DBS is less expensive• DBS are a universally available sample• PEth is stable at RT for at least 6 months, indefinitely at -80oC• The DBS sample can be collected and analyzed sooner• Specimen integrity improved since DBS are a single collection

Acknowledgements• This research was funded by NIAAA R43 grant AA017792-01

References:(1) Magri, R., Miguez, H., Jones, J. H. S., Rios, R., & Su´arez, H., Bustos, R., et al. (in progress). Drug consumption during pregnancy:

Second study in a maternity hospital in Uruguay—survey and two biomarkers: Meconium and umbilical cord tissue. Manuscriptsubmitted for publication.

(2) Hutson JR, Magri R, Gareri JN, Koren G. The incidence of prenatal alcohol exposure in Montevideo Uruguay as determined bymeconium analysis. Therapeutic drug monitoring. 2010;32(3):311-7. Epub 2010/05/07.

(3) Bakhireva LN, Savich RD, Raisch DW, Cano S, Annett RD, Leeman L, et al. The Feasibility and Cost of Neonatal Screening forPrenatal Alcohol Exposure by Measuring Phosphatidylethanol in Dried Blood Spots. Alcoholism, clinical and experimentalresearch. 2013. Epub 2013/02/21.

Self-report rate PETH positive FAEE positive

Consumed alcohol once per week 6 (7.4%) 6/6 (100%) 2/6 (33.3%)Consumed alcohol twice per month 3 (3.7%) 2/3 (66.7%) 2/3 (66.7%)Consumed alcohol once per month 12 (14.8%) 11/12 (91.7%) 7/12 (58.3%)Consumed alcohol 1 - 3 times during pregnancy 52 (64.2%) 44/52 (84.6%) 23/52 (44.2%)

Unsure of consumption frequency 8 (9.9%) 5/8 (62.5%) 3/8 (37.5%)

* PETH posit ive ≥ 8 ng/mL, **FAEE posit ive ≥ 500 ng/g

Table V. Maternal alcohol consumption frequency patterns based on self-report and PETH in DBS and FAEE in meconium positive result rates from their offspring (of the 81 subjects who reported drinking)

Drank at any point during pregnancy 81 (60.0%)Drank throughout pregnancy 10 (7.4%)Drank during first 3 months 24 (17.8%)Drank during last 6 months 37 (27.4%)Stopped drinking before pregnant 54 (40.0%)Drank during pregnancy, not sure on timing 10 (7.4%)

Table III. Maternal drinking habits based on self-report results (of all 135 subjects)

Self-report rate PETH positive FAEE positive

Drank throughout pregnancy 10 (7.4%) 9/10 (90%) 6/10 (60%)Drank during first 3 months 24 (17.8%) 22/24 (91.7%) 8/24 (33.3%)Drank during last 6 months 37 (27.4%) 30/37 (81.1%) 18/37 (48.6%)Drank during pregnancy, not sure on timing 10 (7.4%) 8/10 (80%) 5/10 (50%)

Stopped drinking before pregnant 54 (40.0%) 39/54 (72.2%) 23/54 (42.6%)

Table IV. Maternal drinking duration habits based on self-report and PETH in DBS and FAEE in meconium positive result rates from their offspring (of all 135 subjects)

* PETH posit ive ≥ 8 ng/mL, **FAEE posit ive ≥ 500 ng/g