Phosphatidylethanol in post-mortem brain: correlation with blood alcohol concentration and alcohol use disorder

Phosphatidylethanol (PEth) is an alcohol derivative that has been employed as a blood-based biomarker for regular alcohol use. This study investigates the utility of phosphatidylethanol (PEth) as a biomarker for assessing alcohol consumption in post-mortem brain tissue. Using samples from the New South Wales Brain Tissue Resource Centre, we analysed PEth(16:0/18:1) levels in the cerebellum and meninges of individuals with varying histories of alcohol use, including those diagnosed with alcohol use disorder (AUD) and controls. Our findings demonstrate a significant correlation between PEth levels and blood alcohol content (BAC) at the time of death, supporting the biomarker's sensitivity to recent alcohol intake. Furthermore, this study explores the potential of PEth levels in differentiating AUD cases from controls, taking into consideration the complexities of diagnosing AUD post-mortem. The study also examined the relationship between PEth levels and liver pathology, identifying a link with the severity of liver damage. These results underscore the value of PEth as a reliable indicator of alcohol consumption and its potential contributions to post-mortem diagnostics and consequently, research into alcohol-related brain damage.

Stability of PEth 16:0/18:1, 16:0/18:2, 16:0/20:4, 18:0/18:1, 18:0/18:2, and 18:1/18:1 in authentic whole blood samples (at room temperature)

Phosphatidylethanol (PEth) is a direct alcohol biomarker to monitor individuals' drinking behavior that has gained recognition in clinical and forensic settings. The increasing application of the marker makes investigation of the preanalytical handling necessary, and analyte stability deserves major attention. This study was conducted to investigate the change of six PEth homologues' concentration, stored in authentic samples of EDTA blood over a course of 30 days at room temperature (n = 62). The stability criterion of concentration being ±15% of the original concentration was fulfilled at mean for 10, 3, 2, 5, 2, and 7 days for PEth 16:0/18:1, 16:0/18:2, 16:0/20:4, 18:0/18:1, 18:0/18:2, and 18:1/18:1, respectively. Regarding all homologues, there were samples in which concentration had declined by >15% or by more than the critical difference on day 1. Overall, calculated concentration declines were very inhomogeneous, with inter-sample differences of 43%-73% after 30 days. PEth 16:0/18:2, 16:0/20:4, and 18:0/18:2 declined to a greater extent than PEth 16:0/18:1. Blood alcohol concentration was measured >0.1‰ in 25 samples. Three of the six samples that exceeded 115% of initial concentrations were positive for blood alcohol. The study results add to the previously reported information on PEth stability and firstly look at six homologues in comparison. Due to the high scatter of stability among the samples and the observed poor stabilities in some, it can be concluded that transportation and storage times, especially if cooling cannot be provided, must be kept short. If analyzing from dried blood, spotting should preferably be conducted at the site of sampling.

Phosphatidylethanol (B-PEth) and other direct and indirect biomarkers of alcohol consumption

When identifying, preventing and treating alcohol use disorder, a correct estimation of alcohol intake is essential. An objective marker is preferred as self-reported alcohol intake suffers from bias, and the use of alcohol biomarkers is increasing globally. An easy-to-use blood biomarker to correctly assess alcohol consumption is an invaluable asset in alcohol treatment strategies, as well as in alcohol research studies. The specific, cumulative, biomarker phosphatidylethanol, mirroring the past two weeks of consumption, has shown superiority over traditional biomarkers and is an attractive choice of proxy for alcohol intake.

You can't handle the truth! Comparing serum phosphatidylethanol to self-reported alcohol intake in chronic liver disease patients

BACKGROUND

Serum phosphatidylethanol (PEth) testing has emerged as a promising biomarker for assessing recent alcohol consumption, surpassing the limitations of self-reported data. Limited clinical data exists comparing PEth levels and patients' reported alcohol intake.

AIMS

Compare PEth testing results with self-reported alcohol intake and assesses variables associated with underreporting.

METHODS

Single-center retrospective cohort of patients with a diagnosis of chronic liver disease and serum PEth. A patient's first positive PEth (>/=10 ng/mL) and self-reported alcohol consumption was used. PEth results were categorized as mild (10-20), moderate (20-200), or heavy (>200). Severity measures between self-report and PEth were assessed using Bhapkar's test and Bonferroni-adjusted McNemar's tests. Demographic data was analyzed using Chi-Square tests.

RESULTS

279 patients were included. 94 (33.7%) patients had consistency with self-report, and 185 patients had inconsistencies in their report (66.3%, p < 0.001). Of 279 patients, 161 (57.7%) underreported their alcohol consumption, and 55 (19.7%) heavy PEth patients underreported alcohol consumption as light. 58% of alcohol-related and 56.4% of non-alcohol-related cirrhotic patients underreported their alcohol use.

CONCLUSION

In our cohort, only one third of self-reported alcohol consumption was consistent with the PEth level. Notably, 57.7% underreported alcohol intake. Our study reinforces the clinical importance of PEth testing as an objective clinical measure.

Clinical Utility and Impact of Phosphatidylethanol Testing in Liver Transplantation Evaluations

BACKGROUND

Phosphatidylethanol (PEth) is a serum biomarker that can detect alcohol use within the last 28 days with excellent sensitivity and specificity. Urinary ethyl glucuronide (uEtG) is commonly used in transplant settings to screen for alcohol use; however, it has several limitations relevant to liver transplantation. Transplant centers are beginning to regularly utilize PEth as part of the screening process for high-risk liver transplantation candidates although the clinical utility of uniform pre-transplant PEth testing is unclear.

METHODS

This was a retrospective chart review of all patients evaluated for liver transplantation from December 1, 2019, through May 31, 2022, at a large academic tertiary referral center utilizing uniform serum PEth and uEtG screening. Information regarding the patients' transplantation status, age, sex, race, Model for End-Stage Liver Disease score, and PEth levels was obtained. In those with a positive PEth, we examined if the result would have been detected with uEtG, identified a discrepancy from the documented patient report of last use, led to a change in the Psychosocial Assessment of Candidate for Transplantation score, or influenced the transplant selection committee's decision.

RESULTS

Our sample included 865 individuals (mean age = 55.20, 61.27% male and 82.54% white) with calculated Model for End-Stage Liver Disease-Sodium scores ranging from 6.43 to 50.65 (mean: 18.09; median: 16.46). Forty-eight patients were found to have a positive PEth (PEth range 20-1833); 75% of the sample had alcohol-associated liver disease. In 23 of 48 (47.91%) cases, the positive PEth identified alcohol use missed by a concomitant uEtG screen. A positive PEth test identified a discrepancy from patients' self-report in 29 (60.42%) cases and influenced the selection committee's decision in 28 cases (58.33%).

CONCLUSION

Uniform pretransplant PEth screening of liver transplant candidates at the time of initial evaluation identified alcohol use that would have been missed by uEtG testing, identified discrepancies from the patient's self-report, and influenced clinical decision-making in a significant number of cases. These findings support the use of uniform PEth screening in liver transplantation evaluations.

LC-MS/MS analysis of erythrocyte phosphatidylethanol in haematocrit-corrected whole blood versus isolated erythrocytes: Results of an inter-laboratory comparison

Phosphatidylethanol (PEth) is a non-oxidative metabolite of alcohol (ethanol), which is a sensitive and specific indicator of historic ethanol consumption. Although PEth production from ethanol is catalysed by the ubiquitous enzyme phospholipase D, it resides mainly within the erythrocyte compartment of the blood. PEth analysis has been reported in different preparations of whole blood, representing one of the barriers of inter-laboratory comparisons. We previously reported that expressing PEth concentrations in terms of blood erythrocyte content is more sensitive than whole blood volume, and haematocrit-corrected liquid whole blood calculations of erythrocyte PEth and isolated erythrocyte PEth concentrations are comparable when assayed under identical analytical conditions. Acceptance of a clinical diagnostic assay by accreditation bodies requires proficiency testing with a third-party analytical facility. To explore different blood preparations within the same inter-laboratory program, 60 matched isolated erythrocyte or liquid whole blood specimens were tested at three laboratories. Laboratories measured PEth by liquid chromatography-tandem mass spectrometry (LC-MS/MS), two using isolated erythrocytes, while the third used liquid whole blood, which underwent haematocrit correction before comparison with isolated erythrocyte PEth concentrations. There was acceptable consensus (87%) among laboratories to detect PEth around a cut-off of 35 μg/L of erythrocytes. Each laboratory correlated well with the group average PEth concentration (R > 0.98) for each specimen above the cut-off. Differences were observed between laboratories in bias, which did not affect comparable sensitivity at the selected cut-off. This work demonstrates the feasibility of an inter-laboratory comparison for erythrocyte PEth analysis across different LC-MS/MS methodologies and different blood preparations.

Development of an LC-MS/MS assay with automated sample preparation for phosphatidylethanol (PEth)- Not your typical clinical marker

Phosphatidylethanol (PEth) is a group of phospholipids formed exclusively in the presence of ethanol on the erythrocyte membrane, making it a direct biomarker for long-term ethanol consumption for which a clinical reference interval has been established. Here, we describe an assay for quantitation for two most abundant PEth homologues, PEth 16:0/18:1 and PEth 16:0/18:2, from human whole blood, and present challenges overcome throughout the development process. Since PEth is localized within erythrocyte membranes, a reliable sample preparation technique is an important aspect of PEth analysis. Therefore, various erythrocyte lysing agents for recovery of exogenously spiked standards and controls were evaluated to identify one that performed comparably to the recovery of endogenous analytes found in authentic samples. A supported liquid extraction (SLE) technique was employed for sample cleanup and enrichment which together with liquid chromatography-tandem mass spectrometry (LC-MS/MS) analysis enabled automated sample preparation, appropriate chromatographic resolution, and minimal system carryover. This resulted in a laboratory developed test with an analytical measurement range (AMR) of 10-1000 ng/mL (slope = 0.9902-1.0138, R2 = 0.9958-0.9972), that was precise (intra-day precision: 3.4-4.1%; inter-day precision: 4.4-8.2% over the AMR), accurate when compared with an available external laboratory test (slope = 0.9943-1.0206, R2 = 0.9635-0.9678, no lower decision point interpretation changes), with effective analyte recovery (77.2-83.5%), and established stability characteristics, while chromatographically separating the analytes to ensure no additive effects due to the isotopic distribution of the opposing analyte.

Development and validation of an LC-MS/MS method to quantify the alcohol biomarker phosphatidylethanol 16:0/18:1 in dried blood spots for clinical research purposes

Phosphatidylethanol (PEth) is a group of phospholipids detectable in red blood cells exclusively following ethanol consumption. The primary PEth analog, PEth 16:0/18:1, has an extended half-life in red cells, providing a long window of detection and tremendous potential for the quantification of cumulative alcohol consumption. We developed and validated an LC/MS-MS method to quantify PEth 16:0/18:1 in dried blood spots (DBS) for clinical research purposes. Method development and validation followed FDA guidance but expanded on prior published methods through the evaluation of additional DBS-specific factors such as sample hematocrit, punch location, and spot volume. This method was applied to the quantification of PEth in participant samples.

Effect of two counseling interventions on self-reported alcohol consumption, alcohol biomarker phosphatidylethanol (PEth), and viral suppression among persons living with HIV (PWH) with unhealthy alcohol use in Uganda: A randomized controlled trial

PURPOSE

To test the efficacy of two interventions to reduce alcohol use and increase viral suppression compared to a control in persons with HIV (PWH).

METHODS

In a three-arm (1:1:1) randomized controlled trial (N = 269), we compared in-person counselling (45-70 minutes, two sessions over three months) with interim monthly booster phone calls (live call arm) or twice-weekly automated booster sessions (technology arm) to a brief advice control arm. We enrolled PWH self-reporting unhealthy alcohol use (Alcohol Use Disorders Identification Test - Consumption, prior three months, women ≥3, men ≥4). Primary outcomes were number of self-reported drinking days (NDD) in the prior 21 and biomarker phosphatidylethanol (PEth) at six and nine months and viral suppression (<40 copies/mL) at nine months; we adjusted for sex and baseline outcomes.

RESULTS

At baseline, mean 21-day NDDs were 9.4 (95 % CI: 9.1-9.8), mean PEth was 407.8 ng/mL (95 % CI: 340.7-474.8), and 89.2 % were virally suppressed. At follow-up, there were significant reductions in mean NDDs for the live call versus control arm (3.5, 95 % CI:2.1-4.9, p < 0.001) and for the technology versus control arm (3.6, 95 % CI: 2.2-5.1, p < 0.001). The mean PEth differences compared to the control arm were not significant, i.e. 36.4 ng/mL (95 % CI: -117.5 to 190.3, p = 0.643) for the live call and -30.9 ng/mL (95 % CI: -194.8 to 132.9, p = 0.711) for the technology arm. Nine-month viral suppression compared to the control was similar in the live call and in the technology arm.

CONCLUSION

Intervention effects were found on self-reported NDD but not PEth or viral suppression, suggesting no treatment effect. (NCT #03928418).

Increase of PEth after single consumption of alcohol and evaluation of a volumetric DBS filter paper device

Direct alcohol biomarkers are of growing interest for the assessment of alcohol consumption, with particular interest in phosphatidylethanol (PEth) in recent years. PEth is only formed when alcohol is present in the body. However, there is no statement about how much the PEth concentration increases after single moderate alcohol consumption. This study was conducted to determine the increase in PEth concentrations after a single drinking event. Additionally, a new volumetric sampling device (DBSV) was evaluated, which was designed to simplify further sampling processes and to allow for easy self-sampling. Dried blood samples from 31 volunteers were collected before and after single alcohol consumption with mean maximum breath alcohol concentration (BrAC) of 0.4 mg/L (range: 0.30 - 0.55 mg/L). PEth concentrations were determined after automated extraction by liquid chromatography-tandem mass spectrometry. PEth 16:0/18:1 and PEth 16:0/18:2 concentrations increased to an average of 45 ng/mL each in patients starting below 20 ng/mL (range: 25.0 - 57.0 ng/mL for PEth 16:0/18:1; range 26.8 - 62.3 ng/mL for PEth 16:0/18:2). PEth concentrations in patients starting above 20 ng/mL increased by a mean of 30 ng/mL (range: 6.2 - 71.3 ng/mL for PEth 16:0/18:1; range 8.8 - 65.3 ng/mL for PEth 16:0/18:2). In addition, the comparison of the new sampling device DBSV with a standard filter paper card (with volumetrically applied 20 µL blood samples) yielded a close agreement for the determined PEth concentrations in 24 forensic samples and 3 external controls. Therefore, the sampling device DBSV proved to be suitable for the determination of PEth concentrations in blood.

Alcohol-focused and transdiagnostic treatments for unhealthy alcohol use among adults with HIV in Zambia: A 3-arm randomized controlled trial

BACKGROUND

Clinical and quality of life outcomes in people living with human immunodeficiency virus (PLWH) are undermined by unhealthy alcohol use (UAU), which is highly prevalent in this population and is often complicated by mental health (MH) or other substance use (SU) comorbidity. In sub-Saharan Africa, evidence-based and implementable treatment options for people with HIV and UAU are needed.

METHODS

We are conducting a hybrid clinical effectiveness-implementation trial at three public-sector HIV clinics in Lusaka, Zambia. Adults with HIV, who report UAU, and have suboptimal HIV clinical outcomes, will be randomized to one of three arms: an alcohol-focused brief intervention (BI), the BI with additional referral to a transdiagnostic cognitive behavioral therapy (Common Elements Treatment Approach [CETA]), or standard of care. The BI and CETA will be provided by HIV peer counselors, a common cadre of lay health worker in Zambia. Clinical outcomes will include HIV viral suppression, alcohol use, assessed by audio computer-assisted self-interview (ACASI) and direct alcohol biomarkers, Phophatidylethanol and Ethyl glucuronide, and comorbid MH and other SU. A range of implementation outcomes including cost effectiveness will also be analyzed.

CONCLUSION

Hybrid and 3-arm trial design features facilitate the integrated evaluation of both brief, highly implementable, and more intensive, less implementable, treatment options for UAU among PLWH in sub-Saharan Africa. Use of ACASI and alcohol biomarkers will strengthen understanding of treatment effects.

Significantly elevated phosphatidylethanol levels in recent suicide attempters, but not in depressed controls and healthy volunteers

INTRODUCTION

Suicide is a complex transdiagnostic phenomenon. It is strongly associated with, but not exclusive to major depressive disorder (MDD). Hazardous alcohol drinking has also been linked to an increased risk of suicidal behaviours, however, it is often underreported. The study aimed to evaluate whether an objective measure of chronic alcohol use, phosphatidylethanol (PEth) could be useful as a biomarker in clinical practice.

METHOD

ology. The present case-control multi-centric study recruited 156 participants into three study groups: 52 patients treated for major depressive disorder (MDD), 51 individuals immediately following a suicide attempt (SA), and 53 volunteers. Sociodemographic data, medical history, and laboratory data, including PEth concentrations and C-reactive protein levels, were collected from study participants.

RESULTS

PEth concentrations were the highest in suicide attempters (232,54 ± 394,01 ng/ml), followed by patients with MDD (58,39 ± 135,82 ng/ml), and the control group (24,45 ± 70,83 ng/ml) (Kruskall Wallis χ2 = 12.23, df = 2, p = .002). In a multinomial logistic regression model with adjustments, PEth concentration was able to predict belonging to suicide attempters' group, but not to depression group (p = .01). Suicide attempters were also more likely to underreport their recent alcohol consumption.

LIMITATIONS

We did not analyze SA methods, psychiatric comorbidity and several other factors that might be associated with PEth levels, such as body mass index, race, and haemoglobin levels. Sample recruited in hospital settings may not be representative of the whole population. The results of this adult-only study cannot be generalized to adolescents.

CONCLUSIONS

PEth levels in recent suicide attempters significantly exceeded those of patients with MDD and controls. Suicide attempters also were more likely to underreport their alcohol consumption when questioned about their consuption. PEth might be an interesting biomarker to evaluate individuals at risk of SA.

Identification of unhealthy alcohol use by self-report and phosphatidylethanol (PEth) blood concentrations in an acute psychiatric department

BACKGROUND

The use of standard screening methods could improve the detection rate of unhealthy alcohol use in patients admitted to psychiatric acute and emergency departments. The aim of the present study was to investigate the ability of the alcohol biomarker phosphatidylethanol (PEth) to identify patients with high levels of alcohol consumption prior to admission.

METHODS

The data were prospectively collected at admittance to an acute psychiatric department in the period January 2016 to June 2017. A blood sample for the analysis of PEth was available from 177 patients. We compared the PEth concentrations with the Alcohol Use Disorders Identification Test (AUDIT) scores during the hospital stay, and psychiatric diagnoses at discharge.

RESULTS

A total of 45.8% of the patients had a PEth concentration ≥ 0.03 μmol/L, indicating significant alcohol consumption. AUDIT scores consistent with unhealthy alcohol use were present in 51.7%. There was a significant positive correlation between PEth concentrations and AUDIT scores (r = 0.631, p < 0.001). PEth was above the detection limit of 0.03 μmol/L in 19% of those reporting an average daily intake of zero alcohol units per day during the last week before admission. PEth concentrations were significantly higher among those with an alcohol diagnosis than among those without such a diagnosis (0.82 μmol/L vs. 0.09 μmol/L, p = 0.001).

CONCLUSION

PEth provides supplementary information on recent alcohol consumption in a psychiatric population and would be particularly helpful in patients unable or unwilling to give such information at admission.

Comparison of automated determination of phosphatidylethanol (PEth) in dried blood spots (DBS) with previous manual processing and testing

Phosphatidylethanol (PEth) is a sensitive and specific biomarker of alcohol consumption in the prior 2-3 weeks. Standard, manual PEth testing using dried blood spots (DBS) is a multi-step time-consuming process. A novel, automated processing and testing method has been developed to decrease DBS processing and testing time. We conducted automated testing, using regioisomerically pure PEth reference material, on randomly selected DBS, which had previously been tested via manual methods and then stored for 3-6 years at -80 °C, to compare the results (PEth 16:0/18:1 homologue). We chose samples for re-testing using categories found in the literature as follows: 1) PEth <20 ng/mL; 2) PEth 20-200 ng/mL; 3) PEth >200-1000 ng/mL; 4) PEth >1000 ng/mL. We calculated agreement between the categories using the weighted kappa statistic (n = 49 DBS). We quantified agreement between continuous measures using the intraclass correlation coefficient (ICC), and further described the relationship between variables using Spearman correlation. The median PEth result was 155 ng/mL (interquartile range [IQR]: 1-1312 ng/mL) via automated methods and 98.8 ng/mL (IQR: 10.2-625.0 ng/mL) via manual methods. The weighted kappa comparing the automated to manual PEth results was 0.76 [95% Confidence Interval (CI): 0.66-0.86]. The ICC was 0.69 (95% CI: 0.54-0.79), and the Spearman correlation was 0.98 (95% CI: 0.95-0.99). While the new methods yielded somewhat higher PEth values, we found good to excellent agreement between clinically relevant PEth categories. Automated DBS processing and testing using new reference standards are promising methods for PEth testing.

Phosphatidylethanol in patients with liver diseases of different etiologies: Analysis of six homologues and comparison with other alcohol markers

BACKGROUND AND AIMS

Phosphatidylethanol (PEth) is a direct alcohol biomarker. Aim of the study was to evaluate the performance of six homologues of PEth in comparison to other alcohol markers in patients with liver diseases.

METHODS

The study included 234 patients with liver disease, who gave statements about alcohol consumption during the three months prior to the doctor's appointment. Ethylglucuronide in urine (uEtG) and in hair (hEtG) and carbohydrate-deficient transferrin (CDT) were analyzed in addition to PEth.

RESULTS

Of all patients 47% stated to have drunk alcohol during the past three months. UEtG, hEtG and CDT showed a sensitivity of 29% and a specificity of 92% together for ingestion of at least two standard drinks (24 g) per week. With PEth 16:0/18:1 in addition, sensitivity increased to 59%. For consumption in the last week uEtG's sensitivity and specificity was 28% and 100%, respectively. PEth's was 75% and 93%. When looking at patients who consumed at least two standard drinks per week during the past three months and of which a hair sample could be obtained, hEtG's sensitivity was 37% and specificity 90%. PEth had a sensitivity of 53% and specificity of 100%. Quotients of PEth 16:0/18:1 with 16:0/18:2, 16:0/20:4 and 18:0/18:2 were smaller when alcohol had been consumed more recently.

CONCLUSION

Despite the rather poor overall sensitivity of alcohol biomarkers in this study, PEth showed best sensitivity for all time periods of alcohol consumption.

Phosphatidylethanol, ethyl glucuronide and ethanol in blood as complementary biomarkers for alcohol consumption

Alcohol biomarkers can monitor both recent and long-term drinking and provide information about drinking habits as a complement to self-reporting. Ethyl glucuronide (EtG) and phosphatidylethanol (PEth) are the most sensitive available biomarkers for this purpose. The present study aimed to collect data on both PEth and EtG in the same blood sample, in addition to ethanol, in order to evaluate the combined use of these biomarkers. Venous EDTA blood samples (n = 1149) sent to the laboratory as part of a clinical routine service for measuring PEth were investigated. PEth and EtG concentrations were analyzed using liquid chromatography-mass spectrometry methods and ethanol with an enzymatic method. Of the 1149 samples, 95 were positive for ethanol (range 0.11-3.12 g/L), 454 for EtG (1.0-9739 ng/mL), 635 for PEth (0.014-6.0 µmol/L), 534 for PEth ≥ 0.050 µmol/L, and 315 for PEth ≥ 0.30 µmol/L. EtG and PEth concentrations seemed largely independent as the coefficient of determination (r²) between PEth and EtG concentrations was 0.15. However, when the EtG concentrations were evaluated for different subgroups depending on ethanol or PEth concentrations a statistically significant difference between successive higher concentrations was observed. EtG and PEth are independent measures of recent alcohol drinking reflecting different time windows. Their combined measurement in the same blood sample is possible and will provide valuable information regarding recent alcohol consumption as a complement to self-reporting.

Investigating the use of PEth, CDT and MCV to evaluate alcohol consumption in a cohort of homeless individuals- A comparison of different alcohol biomarkers

In a cohort including individuals with suspected high alcohol consumption, the concentrations of the indirect alcohol biomarkers carbohydrate-deficient transferrin (CDT) and mean corpuscular volume (MCV) and the direct alcohol biomarker phosphatidylethanol (PEth) were investigated. Blood alcohol concentration (BAC) was analysed as a marker for acute alcohol ingestion. In addition to questions about subjective alcohol consumption behaviour, 147 homeless persons underwent a physical examination with blood sampling. BAC, PEth, CDT and MCV were determined in the blood samples. Special focus was on the comparison of PEth and CDT for indicating excessive alcohol consumption. BAC was measured above 0.1‰ in 39 blood samples (0.1-2.5‰, median 0.75‰). PEth was detected in all of them. Overall, PEth was positive (≥10 ng/ml) in 104 samples (71%) (11-5687 ng/ml, median 650 ng/ml) with 68 (46%) being above the cut-off for excessive alcohol consumption (210 ng/ml). In 26 subjects PEth was the only positive alcohol biomarker. CDT was ≥ 1.7% in 66 cases (47%) (1.8-22.2%, median 4.4%) and ≥ 2.5% in 52 (35%) cases. MCV was elevated (≥95 fl) in 58 subjects (39%). CDT and PEth concentrations showed a significant positive correlation (spearman's correlation coefficient ρ = 0.77, p < 0.001). PEth concentrations were significantly higher in samples that were also CDT positive than solely PEth positive (p = 0.004). PEth did not indicate excessive alcohol consumption (< 210 ng/ml) in eight and two cases in which CDT was ≥ 1.7% and ≥ 2.5%, respectively. On the other hand, CDT was< 1.7% and< 2.5% in ten and 18 cases, respectively, in which PEth was above cut-off for excessive alcohol consumption. Taking the self-reports of the participants into consideration, PEth's sensitivity for detecting excessive alcohol consumption was 100% (10 ng/ml) and 94% (210 ng/ml) and CDT's was 88% (1.7%) and 75% (2.5%). In individuals of the investigated cohort unusually high concentrations of the alcohol consumption markers PEth and CDT were quantified, which proves the assumption of chronic excessive alcohol consumption in parts of the cohort. PEth was the marker that was positive most often and was more sensitive for excessive alcohol consumption than CDT.

Heavy Alcohol Use is Associated with Lower CD4 Counts among Russian Women Living with HIV: A Multilevel Analysis

Alcohol use remains prevalent among Russian women with HIV infection. Multilevel mixed effects models were used to estimate the association of heavy drinking and HIV outcomes among women (N = 250 at baseline; N = 207 at follow-up), aged 18-35, engaged in HIV care in Saint Petersburg. Alcohol use was assessed at baseline and 3 months by self-report and by the biomarker phosphatidylethanol (PEth). Overall, 35% of women were heavy drinkers, defined as women reporting ≥ 1 past-30-day heavy drinking episode (≥ 4 standard drinks on one occasion) or with PEth blood levels ≥ 80 ng/mL. Women who engaged in heavy drinking had an average 41 CD4 cells/mm³ (95% CI = - 81, - 2; z = - 2.04; P = 0.042) fewer than those who did not. Heavy drinking was associated with higher HIV symptom burden (IRR = 1.20; 95% CI = 1.05, 1.36; z = 2.73; P = 0.006) and suboptimal antiretroviral adherence (OR = 3.04; 95% CI = 1.27, 7.28; χ² = 2.50; P = 0.013), but not with viral load. Findings support the integration of alcohol treatment interventions as part of routine HIV care in Russia.

Fully automated correction for the hematocrit bias of non-volumetric dried blood spot phosphatidylethanol analysis

The quantitative analysis of substances in dried blood spots (DBS) has gained vast popularity in the past decade. The World Anti-Doping Agency (WADA) also recently committed to implementing DBS. Currently, DBS sampling mainly has focused on various volumetric sampling devices such as Hemaxis, Capitainer, and Mitra. These devices are designed to collect a specific sample volume, independent of the hematocrit (HCT), to enable quantitative DBS analysis. Here, we present an automated solution that makes the necessity of volumetric sampling for quantitative DBS analysis obsolete. Combining automated reflectance-based HCT correction in combination with fully automated DBS LC-MS/MS analysis, the novel strategy permits high-throughput analysis in combination with HCT independence. Studying the model compound phosphatidylethanol 16:0/18:1, which is HCT-dependent due to incorporation into red blood cells, an implementation of DBS HCT normalization is presented. First, the performance of the automated HCT module with DBS is demonstrated compared to standardized HCT analysis from whole blood using a centrifuge. Second, the HCT dependency of fully automated PEth analysis from DBS is evaluated. Third, a solution to correct for the HCT dependency of PEth using the HCT scanner is presented. The study demonstrates that as soon as the HCT dependence of an analyte is known, a correction factor can be applied for the normalization of HCT levels. In the context of PEth, a linear increase in PEth concentration was observed, as the analyte is primarily located within the cellular fraction. Based on the obtained results, the use of a common correction factor for PEth DBS is possible.

The Drinkers' Intervention to Prevent Tuberculosis (DIPT) trial among heavy drinkers living with HIV in Uganda: study protocol of a 2×2 factorial trial

Background

The risk of tuberculosis (TB) is high among people with HIV (PWH). Heavy alcohol drinking independently increases TB risk and approximately 25% of PWH globally engage in heavy drinking. While isoniazid (INH) preventive therapy decreases TB incidence and mortality among PWH, heavy drinking during INH is associated with liver toxicity and poor adherence. Interventions are, therefore, urgently needed to decrease alcohol use and improve adherence to INH in this population in settings with high prevalence of HIV and TB like Uganda.

Methods

The Drinkers’ Intervention to Prevent TB (DIPT) study is a 2×2 factorial randomized controlled trial among HIV/TB co-infected adults (≥18 years) who engage in heavy alcohol drinking and live in Uganda. The trial will allocate 680 participants with a 1:1:1:1 individual randomization to receive 6 months of INH and one of the following interventions: (1) no incentives (control), (2) financial incentives contingent on low alcohol use, (3) financial incentives contingent on high adherence to INH, and (4) escalating financial incentives for both decreasing alcohol use and increasing adherence to INH. Incentives will be in the form of escalating lottery-based monetary rewards. Participants will attend monthly visits to refill isoniazid medications, undergo liver toxicity monitoring, and, except for controls, determine eligibility for prizes. We will estimate (a) the effect of incentives contingent on low alcohol use on reduction in heavy drinking, measured via a long-term objective and self-reported metric of alcohol use, at 3- and 6-month study visits, and (b) the effect of incentives contingent on high adherence to INH, measured as >90% pill-taking days by medication event monitoring system cap opening. We will use qualitative methods to explore the mechanisms of any influence of financial incentives on HIV virologic suppression.

Discussion

This study will provide new information on low-cost strategies to both reduce alcohol use and increase INH adherence among people with HIV and TB infection who engage in heavy drinking in low-income countries with high HIV and TB prevalence.

Trial registration

ClinicalTrials.gov NCT03492216. Registered on April 10, 2018

Objective assessment of alcohol consumption in early pregnancy using phosphatidylethanol: a cross-sectional study

Background

Alcohol consumption during pregnancy is associated with major birth defects and developmental disabilities. Questionnaires concerning alcohol consumption during pregnancy underestimate alcohol use while the use of a reliable and objective biomarker for alcohol consumption enables more accurate screening. Phosphatidylethanol can detect low levels of alcohol consumption in the previous two weeks. In this study we aimed to biochemically assess the prevalence of alcohol consumption during early pregnancy using phosphatidylethanol in blood and compare this with self-reported alcohol consumption.

Methods

To evaluate biochemically assessed prevalence of alcohol consumption during early pregnancy using phosphatidylethanol levels, we conducted a prospective, cross-sectional, single center study in the largest tertiary hospital of the Netherlands. All adult pregnant women who were under the care of the obstetric department of the Erasmus MC and who underwent routine blood testing at a gestational age of less than 15 weeks were eligible. No specified informed consent was needed.

Results

The study was conducted between September 2016 and October 2017. In total, we received 1,002 residual samples of 992 women. After applying in- and exclusion criteria we analyzed 684 samples. Mean gestational age of all included women was 10.3 weeks (SD 1.9). Of these women, 36 (5.3 %) tested positive for phosphatidylethanol, indicating alcohol consumption in the previous two weeks. Of women with a positive phosphatidylethanol test, 89 % (n = 32) did not express alcohol consumption to their obstetric care provider.

Conclusions

One in nineteen women consumed alcohol during early pregnancy with a high percentage not reporting this use to their obstetric care provider. Questioning alcohol consumption by an obstetric care provider did not successfully identify (hazardous) alcohol consumption. Routine screening with phosphatidylethanol in maternal blood can be of added value to identify women who consume alcohol during pregnancy.

Mixed-methods trial of a phosphatidylethanol-based contingency management intervention to initiate and maintain alcohol abstinence in formerly homeless adults with alcohol use disorders

Background

Contingency management (CM) is an intervention where incentives are provided in exchange for biochemically confirmed alcohol abstinence. CM is effective at initiating alcohol abstinence, but it is less effective at maintaining long-term abstinence. Phosphatidylethanol (PEth), collected via a finger-stick, can detect alcohol use for 14–28 days. PEth allows for the development of a CM model that includes increasingly less frequent monitoring of abstinence to assist high risk groups, such as formerly homeless individuals, maintain long-term abstinence.

Aims

Investigate whether PEth-based CM intervention targeting alcohol abstinence in formerly homeless, currently housed individuals with alcohol use disorders is: (1) acceptable and feasible for housing program tenants and personnel; and is associated with increased (2) alcohol abstinence and (3) housing tenure.

Methods

Acceptability and feasibility will be assessed using a QUAL+quant mixed-methods design using qualitative interviews and quantitative measures of satisfaction and attrition. Effectiveness will be evaluated through a randomized pilot trial of 50 study participants who will receive 6 months of either treatment as usual (TAU) including incentives (e.g., gift cards) for providing blood samples (Control Condition) or TAU and incentives for negative PEth results (PEth-CM Condition). Outcomes will be assessed during the intervention and at a three-month follow-up visit. The trial will be conducted via telehealth as a result of COVID-19.

Discussion

This protocol seeks to utilize a novel alcohol biomarker to evaluate the acceptability, feasibility, and initial effectiveness of a CM model that encourages long-term abstinence in a high-risk group.

Measurement of the alcohol biomarker phosphatidylethanol (PEth) in dried blood spots and venous blood-importance of inhibition of post-sampling formation from ethanol

Phosphatidylethanol (PEth) is a group of phospholipids formed in cell membranes following alcohol consumption by action of the enzyme phospholipase D (PLD). PEth measurement in whole blood samples is established as a specific alcohol biomarker with clinical and forensic applications. However, in blood specimens containing ethanol, formation of PEth may continue after sampling leading to falsely elevated concentrations. This study evaluated the use of dried blood spot (DBS) and microsampling specimens to avoid post-sampling formation of PEth. Filter paper cards and three commercial devices for volumetric microsampling of finger-pricked blood were assessed, using PEth-negative and PEth-positive whole blood fortified with 2 g/L ethanol. PEth (16:0/18:1) was measured by LC–MS/MS. Post-sampling formation of PEth occurred in wet blood and in the volumetric devices, but not filter paper cards, when stored at room temperature for 48 h. Addition of an inhibitor of PLD, sodium metavanadate (NaVO₃), eliminated post-sampling formation during storage and drying. In conclusion, the present study confirmed previous observations that PEth can be formed in blood samples after collection, if the specimen contains ethanol. The results further demonstrated that post-sampling formation of PEth from ethanol also occurred with commercial devices for volumetric dried blood microsampling. In order for a PEth result not to be questioned, it is recommended to use a PLD inhibitor, whether venous blood is collected in a vacutainer tube or finger-pricked blood is obtained using devices for dried blood microsampling.

Moderate alcohol consumption is associated with advanced fibrosis in non-alcoholic fatty liver disease and shows a synergistic effect with type 2 diabetes mellitus

BACKGROUND

Non-alcoholic fatty liver disease (NAFLD) is the most common chronic liver disease worldwide. Whether moderate alcohol consumption plays a role for progression of NAFLD is disputed. Moreover, it is not known which tool is ideal for assessment of alcohol consumption in NAFLD. This study aimed to evaluate if moderate alcohol consumption assessed with different methods, including the biological marker phosphatidylethanol (PEth), is associated with advanced fibrosis in NAFLD.

METHODS

We conducted a cross-sectional study of patients with biopsy-proven NAFLD. All participants were clinically evaluated with medical history, blood tests, and anthropometric measurements. Alcohol consumption was assessed using PEth in blood, the questionnaire AUDIT-C, and clinical interview.

FINDINGS

86 patients were included of which 17% had advanced fibrosis. All participants reported alcohol consumption < 140 g/week. Average weekly alcohol consumption was higher in the group with advanced fibrosis. Moderate alcohol consumption, independently of the method of assessment, was associated with increased probability of advanced fibrosis (adjusted OR 5.5-9.7, 95% CI 1.05-69.6). Patients with type 2 diabetes mellitus (T2DM) consuming moderate amounts of alcohol had a significantly higher rate of advanced fibrosis compared with those consuming low amounts (50.0-60.0% vs. 3.3-21.6%, p < 0.05).

CONCLUSIONS

Moderate alcohol consumption, irrespective of assessment method (clinical interview, AUDIT-C, and PEth), was associated with advanced fibrosis. PEth in blood ≥ 50 ng/mL may be a biological marker indicating increased risk for advanced fibrosis in NAFLD. Patients with T2DM consuming moderate amounts of alcohol had the highest risk of advanced fibrosis, indicating a synergistic effect of insulin resistance and alcohol on the histopathological progression of NAFLD.

Validating Self-Reported Unhealthy Alcohol Use With Phosphatidylethanol (PEth) Among Patients With HIV

BACKGROUND

We sought to compare self-reported alcohol consumption using Timeline Followback (TLFB) to biomarker-based evidence of significant alcohol use (phosphatidylethanol [PEth] > 20 ng/ml). Using data from patients with HIV (PWH) entering a clinical trial, we asked whether TLFB could predict PEth > 20 ng/ml and assessed the magnitude of association between TLFB and PEth level.

METHODS

We defined unhealthy alcohol use as any alcohol use in the presence of liver disease, at-risk drinking, or alcohol use disorder. Self-reported alcohol use obtained from TLFB interview was assessed as mean number of drinks/day and number of heavy drinking days over the past 21 days. Dried blood spot samples for PEth were collected at the interview. We used logistic regression to predict PEth > 20 ng/ml and Spearman correlation to quantify the association with PEth, both as a function of TLFB.

RESULTS

Among 282 individuals (99% men) in the analytic sample, approximately two-thirds (69%) of individuals had PEth > 20 ng/ml. The proportion with PEth > 20 ng/ml increased with increasing levels of self-reported alcohol use; of the 190 patients with either at-risk drinking or alcohol use disorder based on self-report, 82% had PEth > 20 ng/ml. Discrimination was better with number of drinks per day than heavy drinking days (AUC: 0.80 [95% CI: 0.74 to 0.85] vs. 0.74 [95% CI: 0.68 to 0.80]). The number of drinks per day and PEth were significantly and positively correlated across all levels of alcohol use (Spearman's R ranged from 0.29 to 0.56, all p values < 0.01).

CONCLUSIONS

In this sample of PWH entering a clinical trial, mean numbers of drinks per day discriminated individuals with evidence of significant alcohol use by PEth. PEth complements self-report to improve identification of self-reported unhealthy alcohol use among PWH.

Secondary Analysis of a Randomized Clinical Trial of Naltrexone Among Women Living With HIV: Correlations Between Reductions in Self-Reported Alcohol Use and Changes in Phosphatidylethanol

BACKGROUND

Direct biomarkers such as phosphatidylethanol (PEth) have the capability to detect heavy alcohol use, but it is unclear how strongly self-reported reduction in alcohol use correlates with reduction in PEth. We sought to explore the strength of correlation between reductions in self-reported alcohol use and change in PEth among a sample of women living with HIV (WLWH) who participated in a clinical trial to reduce heavy alcohol use. We also sought to determine whether this correlation was stronger in women with lower body mass index (BMI) and women without an alcohol use disorder (AUD).

METHODS

81 WLWH (mean age = 48.7, 80% Black) engaging in a randomized trial of naltrexone versus placebo with a positive baseline PEth (≥8 ng/ml), and alcohol use data at baseline, 2, and 7 months were included in this analysis. Spearman correlation coefficients were compared to measure the correlation between baseline PEth and number of drinks per week by demographic, biological, and alcohol use factors. Mini-International Neuropsychiatric Interview was used to screen for AUD. Further analyses were stratified by BMI and AUD. Spearman correlation coefficients were calculated for the change in PEth and the change in number of drinks per week over 7 months, including 3 time-points: baseline, 2, and 7 months.

RESULTS

At baseline, the correlation between baseline PEth and the number of drinks per week was significantly stronger for those with a BMI ≤25 compared to those with a BMI > 25 (r = 0.66; r = 0.26, respectively). Similarly, the correlation between baseline PEth and number of drinks was stronger for those who did not screen positive for AUD compared with those who did (r = 0.66; r = 0.25, respectively). When stratifying by BMI, a low-to-moderate correlation (r = 0.32, p = 0.02) was present for persons with a BMI > 25; when stratifying by AUD, a moderate correlation (r = 0.50, p < 0.01) was present for persons without an AUD between 0 and 2 months only.

CONCLUSIONS

In this sample of WLWH, BMI and AUD affected the strength of correlation between PEth and drinks per week. Future work examining changes in PEth over time in broader populations is needed, particularly to understand the sex differences in PEth levels.

Phosphatidylethanol Reliably and Objectively Quantifies Alcohol Consumption in Adolescents and Young Adults

BACKGROUND

Alcohol contributes to numerous annual deaths and various societal problems not just in adult, but also in adolescent, populations. Therefore, it is vital to find methods for reliably detecting alcohol use for early preventative measures. Research has shown phosphatidylethanol (PEth) to be superior to self-report instruments and indirect biomarkers for alcohol consumption in adult populations. However, the transferability onto an adolescent population has not yet been investigated.

METHODS

N = 106 adolescents and young adults aged between 13 and 21 years were included. PEth analysis using high-pressure liquid chromatography-tandem mass spectrometry was performed on dried blood spot samples. Self-report questionnaires for alcohol consumption (Alcohol Use Disorders Identification Test-Consumption, AUDIT-C, and Timeline Followback, TLFB) and drug and alcohol consumption (Detection of Alcohol and Drug Problems in Adolescents, DEP-ADO) were completed by each participant.

RESULTS

AUDIT-C scores showed large correlations with PEth 16:0/18:1 (r_s  = 0.732) and PEth 16:0/18:2 (r_s  = 0.661) concentrations. AUDIT-C with a cutoff value ≥3 was largely correlated with PEth 16:0/18:1 (η = 0.411) and showed a medium-sized correlation with PEth 16:0/18:2 (η = 0.397) concentrations. Using an AUDIT-C cutoff value ≥5 showed large correlations with both PEth 16:0/18:1 (η = 0.510) and PEth 16:0/18:2 (η = 0.497) concentrations, respectively. ROC curves indicated higher PEth concentrations are a good model for detecting positive AUDIT-C cutoff values (AUROC range: 0.800 to 0.849). PEth concentrations showed medium to large correlations with DEP-ADO and TLFB subscales (range r_s  = 0.469 to 0.746).

CONCLUSION

The results suggest that PEth is a reliable and objective marker for quantifying alcohol consumption in adolescents and young adults. This could be of importance for early preventative measures against hazardous alcohol consumption, which is increasingly common at younger ages.

Quantitation of phosphatidylethanol in dried blood after volumetric absorptive microsampling

BACKGROUND

Stimulated by the increased recognition of phosphatidylethanol (PEth) as sensitive direct marker of alcohol intake, the Ghent University's Laboratory of Toxicology and the National Institute of Criminalistics and Criminology combined their efforts to develop a quantitative method. To facilitate implementation the focus was on the use of a sampling technique which allows quick and easy blood collection, without the need of dedicated personnel at any place/any time. In the meantime the cooperation of the two labs should also allow to initiate a Belgian network of laboratories capable of quantifying PEth.

METHODS

Dried blood microsamples were collected via volumetric absorptive microsampling (VAMS). PEth 16:0/18:1 was quantified after liquid-liquid extraction using two independent isotope dilution - liquid chromatography - tandem mass spectrometry methods. A systematic review of the entire process at both sites was performed before the final method comparison using samples from 59 routine toxicology cases collected within a one-year time interval.

RESULTS

Initial differences between both laboratories were solved by focusing on important methodological aspects: (i) trueness verification of the calibration protocol focusing on the primary material, preparation of the stock solutions and adequate equilibration of calibrators and QCs, and (ii) verification of comparability of results obtained with different m/z transitions. Several of these aspects could only be verified by critically assessing spiked and native samples. After a final validation good average comparability of the two methods was observed. The average bias was -0.4%, with 85% of the differences within 20%. Moreover, the methods proved to be reproducible and robust within a one-year time interval.

CONCLUSION

This study is the first to develop a quantitative volumetric absorptive microsampling based method for PEth measurements, in addition it is the first to perform a systematic comparison of PEth measurements between two laboratories. From the discussion on the encountered pitfalls it is clear that also on a global scale, more efforts are needed to improve interlaboratory agreement.

Distributions of alcohol use biomarkers including ethanol, phosphatidylethanol, ethyl glucuronide and ethyl sulfate in clinical and forensic testing

Laboratory tests vary widely in their utility and each test has unique advantages and disadvantages. For the detection of ethanol use and abuse, a variety of direct and indirect markers are available. Alcohol biomarkers provide objective measures for numerous areas of testing including clinical trials, alcohol abuse, postmortem assessment, and drugs of abuse screening. Because the utility of alcohol biomarkers vary depending on the context in which the results will be used, knowing the analogous distribution of results is of value. Herein we report distributions of ethanol in blood, phosphatidylethanol in blood, ethyl glucuronide in urine, and ethyl sulfate in urine for results reported in the last twelve months by our laboratory. Positivity rates were higher for directed analyses when compared to broad screening or panel tests with the highest overall positivity for ethyl glucuronide and ethyl sulfate. The distribution of results for ethyl glucuronide and ethyl sulfate were higher in clinical testing scenarios compared to forensic and a significant correlation between ethyl glucuronide and ethyl sulfate was found consistent with previous reports. Phosphatidylethanol was rarely ordered for forensic use while distributions between routine clinical and clinical trial use were similar. Approximately 21% of all phosphatidylethanol results were in the moderate to chronic alcohol use category. These results provide a summary of four commonly used direct markers for alcohol use with positivity rates and overall quantitative distributions. These data supply insights broken out by various disciplines where applicable providing a concise comparison of results for these markers.

Comprehensive Assessment of Alcohol Consumption in People Living with HIV (PLWH): The New Orleans Alcohol Use in HIV Study

BACKGROUND

High frequency of alcohol use among people living with HIV (PLWH) warrants careful assessment and screening to better understand its impact on HIV disease progression and development of comorbidities. Due to the limitations of the tools used to measure alcohol use, the links to health consequences are not fully understood.

METHODS

We completed a cross-sectional analysis to examine the prevalence of alcohol consumption using multiple alcohol assessment tools and their correlation and consistency in a cohort of PLWH (N = 365) enrolled in the New Orleans Alcohol Use in HIV (NOAH) Study. Alcohol use was assessed with the Alcohol Use Disorders Identification Test (AUDIT), timeline followback (TLFB) Calendar, lifetime drinking history, Alcohol and Drug Addiction Severity Index, and blood levels of phosphatidylethanol (PEth). Spearman's correlations were estimated for continuous measures of alcohol consumption; Wilcoxon rank-sum tests were used to compare means; and logistic regression was used to estimate odds of alcohol use by demographic characteristics.

RESULTS

Self-report of current alcohol use varied from 58.9 to 73.7% depending on the assessment. All the self-reported alcohol measures showed statistically significant correlations with the biological marker PEth. The highest correlation was with TLFB grams (r = 0.67, p < 0.001). Using TLFB, 73.7% of the cohort reported using alcohol in the last 30 days, and 61.6% had a positive PEth value. The prevalence of risky drinkers, meeting the TLFB > 3 (women) or >4 (men) drinks/day or>7 (women) or>14 (men) drinks/week, was 49.0%. Medium-risk drinking defined as an AUDIT score ≥ 8 was reported in 40.3%, and high-risk drinkers/probable AUD (AUDIT score ≥ 16) was met by 17.0% of the cohort.

CONCLUSIONS

Our results demonstrate the importance of comprehensive assessments for alcohol use, including self-report via multiple assessment tools administered by trained staff, as well as the addition of biomarkers for improved classification of subjects into different drinking categories.

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.

Differentiating Types of Self-Reported Alcohol Abstinence

We contrast three types of abstinence: quit after alcohol associated problems (Q-AP), quit for other reasons (Q-OR), and lifetime abstainer (LTA). We summarized the characteristics of people living with HIV (PLWH), and matched uninfected individuals, by levels of alcohol use and types of abstinence. We then identified factors that differentiate abstinence and determined whether the association with an alcohol biomarker or a genetic polymorphism is improved by differentiating abstinence. Among abstainers, 34% of PLWH and 38% of uninfected were Q-AP; 53% and 53% were Q-OR; and 12% and 10% were LTA. Logistic regression models found smoking, alcohol, cocaine, and hepatitis C increased odds of Q-AP, whereas smoking and marijuana decreased odds of LTA. Differentiating types of abstinence improved association. Q-APs and LTAs can be readily differentiated by an alcohol biomarker and genetic polymorphism. Differentiating type of abstinence may enhance understanding of alcohol health effects.

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.

Social Desirability Bias Impacts Self-Reported Alcohol Use Among Persons With HIV in Uganda

BACKGROUND

Self-report is widely used to assess alcohol use in research and clinical practice, but may be subject to social desirability bias. We aimed to determine if social desirability impacts self-reported alcohol use.

METHODS

Among 751 human immunodeficiency virus (HIV)-infected patients from a clinic in southwestern Uganda, we measured social desirability using the Marlowe-Crowne Social Desirability Scale (SDS) Short Form C, self-reported alcohol use (prior 3 months) Alcohol Use Disorders Identification Test-Consumption (AUDIT-C), and phosphatidylethanol (PEth), a biomarker of prior 3 weeks' drinking. We conducted multiple regression analyses to assess the relationship between SDS score (low, medium, and high levels) and (i) any self-reported recent alcohol use, among those who were PEth-positive (≥8 ng/ml), and (ii) continuous AUDIT-C score, among those reporting any recent alcohol use. We controlled for PEth level, age, gender, education, economic assets, marital status, religion, spirituality/religiosity, social support, and study cohort.

RESULTS

Of 751 participants, 59% were women; the median age was 31 years (interquartile range [IQR]: 26 to 39). Median SDS score was 9 (IQR: 4 to 10). Two-thirds (62%) self-reported any recent alcohol use; median AUDIT-C was 1 (IQR: 0 to 4). Among those who were PEth-positive (57%), 13% reported no recent alcohol use. Those with the highest SDS tertile had decreased odds of reporting any recent alcohol use compared to the lowest tertile, but the association did not reach statistical significance in multivariable analyses (adjusted odds ratio 0.55 [95% confidence interval (CI): 0.25, 1.23]). Among participants self-reporting recent alcohol use, SDS level was negatively associated with AUDIT-C scores (adjusted β: -0.70 [95% CI: -1.19, -0.21] for medium vs. low SDS and -1.42 [95% CI: -2.05, -0.78] for high vs. low SDS).

CONCLUSIONS

While use of objective measures (e.g., alcohol biomarkers) is desirable for measuring alcohol use, SDS scores may be used to adjust self-reported drinking levels by participants' level of social desirability in HIV research studies.

Inter Individual Variation and Factors Regulating the Formation of Phosphatidylethanol

BACKGROUND

Alcohol use disorders are a major but often unrecognized health problem. Alcohol markers can therefore be of great value for diagnosis, follow-up, and treatment evaluation. Phosphatidylethanol in blood (B-PEth) is an alcohol biomarker with higher clinical sensitivity and specificity than commonly used alcohol markers but has shown a considerable interindividual variation in relation to reported consumption.

METHODS

An in vitro system was used to investigate factors, which may affect the formation rate of PEth or which may give rise to interindividual variation in the rate of formation. In this system, isolated erythrocytes from 31 individuals were incubated in the presence of various concentrations of ethanol (EtOH). The concentration of PEth and phosphatidylcholine (PC), the parent molecule of PEth, was determined by chromatographic methods.

RESULTS

Time, EtOH, and PC concentration were major factors determining the amount of PEth formed. The interindividual variation in PEth formation rate, calculated at an EtOH concentration of 50 mmol/l, showed a coefficient of variation (CV) from 23 to 31% for the different PEth forms studied (PEth 16:0/18:2, total PEth and PEth 16:0/18:1). The concentration of PC was found to be an important determinant of this variation. The formation rate for PEth 16:0/18:2 was somewhat higher than for PEth 16:0/18:1. The formation of PEth 16:0/18:1 but not PEth 16:0/18:2 showed a positive correlation to the concentration of PEth at baseline (endogenous PEth). Calculation of enzyme kinetics for the reaction resulting in the formation of PEth 16:0/18:1 or PEth 16:0/18:2 showed an apparent K_m (Michaelis constant) of approximately 160 to 170 mmol/l.

CONCLUSIONS

Interindividual variation in the formation rate of PEth appears to be a significant but relatively modest source of variation in the relation between B-PEth and reported consumption. Correction for interindividual variation in PC concentrations might substantially reduce the interindividual variability in PEth formation and consequently in B-PEth.

Discussion: Automated filtration or really just solid phase extraction

In this article, we discuss a recent publication by Casati et al. (2018) focusing on the sample preparation that is described for the analysis of phosphatidylethanols and whether or not their proposed method of 'automated filtration' and the advantages it brings is really just a standard solid phase extraction protocol.

No blue-yellow color vision impairment after acute ethanol ingestion

Several studies showed that chronic ethanol exposure can cause color vision deficiencies. There has been no agreement about the axis of color defects due to alcohol misuse since changes in the red-green and the blue-yellow axis have been described in literature. The acute influence of alcohol on the blue-yellow color vision has not been studied as well. The aim of this study was to determine the effect of acute alcohol ingestion on blue-yellow color vision by using short wavelength automated perimetry (SWAP) and anomaloscopy with the Moreland equation. This is the first study evaluating that question by using SWAP and anomaloscopy. Sixteen healthy subjects without a history of alcohol-related and ophthalmological problems were examined by SWAP and anomaloscopy (Moreland equation) before and after alcohol ingestion. Mean sensitivity (MS), mean deviation (MD), loss of variance (LV), reliability factor (RF), and duration of examination were assessed for perimetry and match midpoint (MP), matching range (MR), and duration of examination for anomaloscopy. Blood alcohol concentrations (BAC) were determined by gas chromatography and phosphatidylethanol concentrations (marker of an alcohol misuse) by liquid-chromatography tandem-mass spectrometry in venous blood samples from a cubital vein. Mean blood BAC was 0.86 ± 0.20 g/kg while performing perimetry and 0.84 ± 0.20 g/kg while performing anomaloscopy (BAC: 0.1 g/kg ≈ 0.01 g/dL). MS, MD, RF, MP, MR, and duration of perimetry examination were not altered significantly after alcohol intake. LV showed a significant increase. The duration of anomaloscope testing was shortened significantly under the influence of alcohol. The subjects also revealed a significantly narrower matching range after alcohol intake. In the range of 0.8 g/kg BAC, no blue-yellow vision deficiencies could be demonstrated. In further studies, the effect of higher BAC on blue-yellow vision should be investigated by different methods.

An automated sample preparation approach for routine liquid chromatography tandem-mass spectrometry measurement of the alcohol biomarkers phosphatidylethanol 16:0/18:1, 16:0/16:0 and 18:1/18:1

BACKGROUND

Phosphatidylethanols (PEths) are currently under investigation as highly sensitive and specific direct biomarkers of long-term alcohol abuse. PEths belong to a group of aberrant phospholipids formed in erythrocyte membranes in presence of ethanol by the catalytic action of the enzyme phospholipase D on phosphatidylcholine. Compared to other alcohol biomarkers, a higher sensitivity (94.5-100%) and specificity (100%) characterizes PEth species.

METHOD

Prior to detection, an important practical aspect in the work-flow of PEths analysis is the sample preparation step. To date, traditional techniques such as liquid-liquid extraction (LLE) and solid phase extraction (SPE) require multiple steps to remove blood interferences. Due to the simplicity of use and the possibility of automation, sample filtration is also a widespread technique in biomedical laboratories. In this work, a reliable sample preparation method based on an automated filtration with Phree™ Phospholipid Removal Plates (Phenomenex, California, USA) was developed to extract PEths from human whole blood. Surface characteristics of Phospholipids Removal material allow phospholipids retention on the filter and a suitable PEths recovery after elution. The blood samples were added with internal standard (IS) and purified in acetonitrile (1 mL). After centrifugation, supernatants were applied to the Phospholipids Removal Plates in an automated workstation. After washing, the phospholipids retained on the filter were eluted with 1-mL 2-propanol 1% ammonia. PEth 16:0/18:1, PEth 16:0/16:0 and PEth 18:1/18:1 were extracted using the proposed method and detected by LC-MS/MS operated in electron spray ionization (ESI). The detection of all compounds was based on multiple reaction monitoring (MRM) transitions. This method was validated for the quantitative profiling of PEth molecular species in human blood collected from heavy and social drinkers.

RESULTS

The method was validated according to Food and Drug Administration (FDA) guidelines. Linearity was observed in the 25-1250 (PEth 16:0/18:1) and 5-250 (PEth 16:0/16:0 and PEth 18:1/18:1) ng/mL range with a correlation coefficient (r²) between 0.997 and 0.999 for all three compounds. Moreover, the nominal concentrations of non-zero calibrators were ±15%. Variation coefficient (%CV) was < 10% for all the analytes, while lowest limit of quantitation (LLOQ) was found to be 1.25 ng/mL for PEth 16:0/18:1, 0.50 ng/mL for PEth 16:0/16:0 and 0.50 ng/mL for PEth 18:1/18:1. Intra- and inter-day precision and accuracy were always lower than 14% and 11%, respectively. Analytical recovery was higher than 68.8% for all analytes. Sample stability at 4 °C and -20 °C showed a concentration drop lower than 20% up to 4 weeks. Extracts were stable for 7 days in the autosampler and 30 days at -20 °C and 4 °C in a closed vial. The procedure was successfully applied to blood samples collected from heavy drinkers (n = 8), social drinkers (n = 5), and teetotalers (n = 7).

CONCLUSIONS

Due to the simplicity of application and the possibility of automation, sample filtration is well suited for a clinical and forensic laboratory. To monitor alcohol consumption, an analytical method based on liquid chromatography-tandem mass spectrometry (LC-MS/MS) with novel and automated sample preparation was developed and validated for the simultaneous quantification of PEth 16:0/18:1, PEth 16:0/16:0 and PEth 18:1/18:1 in whole blood samples, characterized by a fast sample preparation and lower pre-analysis costs than other extraction procedures.

Use of alcohol biomarkers to identify alcohol misuse in organ donors

Phosphatidylethanol is a direct alcohol biomarker for identifying alcohol misuse. It carries several advantages over other alcohol biomarkers, including a detection half-life of several weeks and little confounding by patient characteristics or organ dysfunction. The aim of this study is to derive an optimal phosphatidylethanol cut point to identify organ donors with alcohol misuse, and to assess the impact of alcohol misuse on organ allocation. Discrimination of phosphatidylethanol was evaluated using the area under the ROC curve from a mixed effects logistic regression model. Phosphatidylethanol had an area under the ROC curve of 0.89 (95% CI 0.80-0.98). A phosphatidylethanol cut point of ≥84 ng/mL provided optimal discrimination for the identification of alcohol misuse with a sensitivity of 75% (95% CI 52.9%-89.4%) and a specificity of 97% (95% CI 91%-99%), a positive predictive value of 82% (95% CI 59%-94%), and a negative predictive value of 95% (95% CI 89%-98%). In deceased organ donors who had been critically ill, phosphatidylethanol had good test characteristics to discriminate alcohol misuse. Other alcohol biomarkers performed poorly in deceased organ donors. Liver allocation was decreased in donors with alcohol misuse by proxy history, but not in those with phosphatidylethanol >84 ng/mL, revealing possible information bias in liver allocation.

Pharmacokinetics of Phosphatidylethanol 16:0/20:4 in Human Blood After Alcohol Intake

BACKGROUND

The purpose of this study was to characterize the pharmacokinetics of the phosphatidylethanol (PEth) 16:0/20:4 homolog in uncoagulated human blood samples taken from 18 participants in a clinical laboratory setting after consumption of 2 standard doses of ethanol (EtOH).

METHODS

Male and female participants received either 0.4 or 0.8 g/kg oral doses of EtOH during a 15-minute period. Blood samples were collected before and throughout 6 hours immediately after alcohol administration and then again at days 2, 4, 7, 11, and 14 of the follow-up period. PEth 16:0/20:4 levels were quantified by high-performance liquid chromatography with tandem mass spectrometry detection.

RESULTS

(i) The increase in PEth 16:0/20:4 from baseline to maximum concentration was less than that of PEth 16:0/18:1 or PEth 16:0/18:2 homologs during the 6-hour period after EtOH administration; (ii) the mean half-life of PEth 16:0/20:4 was 2.1 ± 3 (SD) days, which was shorter than the mean half-life of either PEth 16:0/18:1 or PEth 16:0/18:2, 7.6 ± 3 (SD) or 6.8 ± 4 (SD) days, respectively.

CONCLUSIONS

The pharmacokinetics of PEth 16:0/20:4 in whole blood samples is detectable after alcohol consumption and differs in amount synthesized and rate of elimination versus PEth 16:0/18:1 and 16:0/18:2. Measuring the concentrations of these 3 homologs has the potential to provide more information about the amount and time frame of alcohol consumption than any one alone.

The Relationship Between Spirituality/Religiousness and Unhealthy Alcohol Use Among HIV-Infected Adults in Southwestern Uganda

HIV and alcohol use are two serious and co-existing problems in sub-Saharan Africa. We examined the relationship between spirituality and/or religiousness (SR) and unhealthy alcohol use among treatment-naïve HIV-infected adults attending the HIV clinic in Mbarara, Uganda. Unhealthy alcohol was defined as having either an alcohol use disorders identification test-consumption score of ≥4 for men or ≥3 for women, or having a phosphatidylethanol level of ≥50 ng/ml based on analysis of dried bloodspot specimens. Of the 447 participants, 67.8% were female; the median age was 32 years (interquartile range [IQR] 27-40). About half reported being Protestant (49.2%), 35.1% Catholic, and 9.2% Muslim. The median SR score was high (103 [IQR 89-107]); 43.3% drank at unhealthy levels. Higher SR scores were associated with lower odds of unhealthy drinking (adjusted odds ratio [aOR]: 0.83 per standard deviation [SD] increase; 95% confidence interval [CI] 0.66-1.03). The "religious behavior" SR subscale was significantly associated with unhealthy alcohol use (aOR: 0.72 per SD increase; 95% CI 0.58-0.88). Religious institutions, which facilitate expression of religious behavior, may be helpful in promoting and maintaining lower levels of alcohol use.

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.

Formation of phosphatidylethanol from endogenous phosphatidylcholines in animal tissues from pig, calf, and goat

In the presence of alcohol, phosphatidylcholine (PC) is transformed to the direct alcohol biomarker phosphatidylethanol (PEth). This reaction is catalyzed by the enzyme phospholipase D (PLD) and dependent on substrate availability. As recent methods have solely focused on the determination of PEth, information about the PC composition was generally missing. To address this issue and monitor PC (16:0/18:1 and 16:0/18:2) and PEth (16:0/18:1 and 16:0/18:2) simultaneously, a reversed phase LC-MS/MS method based on a C8 core-shell column, coupled to a Sciex 5500 QTrap instrument was developed. By application of polarity switching, at first, PC was measured in ESI positive SRM mode, while PEth was determined at a later stage in ESI negative SRM mode. The PEth method was validated for human blood samples to show its robustness and subsequently applied for the investigation of systematic in vitro PEth formation in animal tissue samples (brain, kidney, liver, and blood) from a pig, a calf, and a goat. Homogenized tissue was incubated at 37°C with varying ethanol concentrations from 1 to 7g/kg (determined by HS-GC-FID) for 5h, whereby a sample was taken every 30min. For all tissue samples, an increase in PEth was measurable. PEth concentrations formed in blood remained below the LLOQ, in agreement with literature. Data analysis of Michaelis-Menten kinetics and PC within the tissue provided a detailed insight about PEth formation, as the occurrence of PEth species can be linked to the observed PC composition. The results of this study show that PEth formation rates vary from tissue to tissue and among different species. Furthermore, new recommendations for PEth analysis are presented.

Phosphatidylethanol in Comparison to Self-Reported Alcohol Consumption Among HIV-Infected Women in a Randomized Controlled Trial of Naltrexone for Reducing Hazardous Drinking

BACKGROUND

Biomarkers can play a key role in supplementing self-report information in alcohol research. In this study, we examined phosphatidylethanol (PEth) in comparison with self-reported alcohol use over time in a randomized controlled trial.

METHODS

Participants were women living with HIV enrolled in a randomized placebo-controlled trial of naltrexone for reducing hazardous drinking. Drinking behavior was measured using Timeline Followback (TLFB), and PEth as a biomarker using dried blood spots. Data collected at baseline, and months 2 and 7 were analyzed. In addition to calculated Spearman's correlations, mixed-effects modeling was used to evaluate the changes in self-reported drinking and PEth, respectively, adjusting for body mass index (BMI).

RESULTS

A total of 194 participants (83% black, mean age 48) were included in the analysis. PEth levels were significantly correlated with self-reported drinking via TLFB, Spearman's r = 0.21 at baseline, r = 0.29 at 2 months, and r = 0.28 at 7 months, respectively. No demographic or health factors, except for BMI, was associated with whether self-report was consistent with PEth. Mixed-effects model indicated that self-reported drinking showed significantly greater reductions in the naltrexone treatment group than the placebo group at the 2- and 7-month visits, whereas PEth measure only showed this difference at the 7-month follow-up.

CONCLUSIONS

The magnitude of the correlation between PEth and self-reported alcohol consumption was small. Caution is needed when using either self-report or PEth as a sole outcome measure for alcohol behavior changes in clinical trials.

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.

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.

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.

Phosphatidylethanol is superior to carbohydrate-deficient transferrin and γ-glutamyltransferase as an alcohol marker and is a reliable estimate of alcohol consumption level

BACKGROUND

In clinical practice as well as research situations, it is of great importance to get reliable information about a patient's alcohol consumption. The aim of the study was to investigate the correlation of alcohol biomarkers (phosphatidylethanol [PEth], carbohydrate-deficient transferrin [CDT], γ-glutamyltransferase, aspartate aminotransferase, and alanine aminotransferase) to retrospective as well as diary-based alcohol self-reports and to examine whether it is possible to correlate a biomarker result to a more precise level of alcohol consumption.

METHODS

One hundred and sixty alcohol-dependent patients were included in a randomized, placebo-controlled clinical trial of pharmacotherapy for alcohol dependence, of which 115 (76 men and 39 women) completed the study. Retrospective alcohol consumption data were collected at baseline, and alcohol diaries were used during the study. Blood samples for determination of alcohol biomarkers were collected on 5 occasions during the study.

RESULTS

PEth and CDT showed a better correlation with alcohol consumption documented in the diary (PEth rs = 0.56 and CDT rs = 0.35) than with retrospective consumption data (PEth rs = 0.23 and CDT rs = 0.22). An even higher correlation (rs = 0.63) was seen between the 2 alcohol biomarkers PEth and CDT. At all consumption levels, PEth had the highest sensitivity of all biomarkers studied.

CONCLUSIONS

PEth was the biomarker with the best correlation to self-reported alcohol consumption. PEth was superior to CDT owing to its substantially higher sensitivity but also due to its closer correlation to self-report. PEth values can be translated into an approximate level of alcohol consumption and PEth appears to be a more reliable measure of alcohol consumption than self-reports.