Blood Phosphatidylethanol Concentrations Following Regular Exposure to an Alcohol-Based Mouthwash

The effect of incidental ethanol exposures on the formation of blood phosphatidylethanol

Blood phosphatidylethanol (PEth), a metabolite of ethanol, is emerging as a direct biomarker of choice for characterizing ethanol consumption in clinical, research, and forensic contexts. An accumulating body of evidence, and a recent international consensus conference, supports a cutoff of 20 μg/L of PEth (16:0/18:1) to distinguish abstinence from beverage ethanol consumption. There is a dearth of research, however, on whether exposures to nonbeverage ethanol sources are sufficient to produce PEth concentrations that exceed this cutoff. To explore this possibility, we recruited 30 participants, who indicated past-90-day abstinence from beverage alcohol, to characterize their past-30-day nonbeverage ethanol exposures (including source, frequency, and intensity of exposures) and to undergo PEth testing. Two of the 30 participants (6.7%) produced PEth concentrations ≥20 μg/L. One of these participants (PEth = 26 μg/L) reported multiple ethanol exposure sources, including near-daily intensive exposures to ethanol vapor. The other participant (PEth = 49 μg/L) reported only once-daily use of an ethanol-containing mouthwash; the veracity of his abstinence claim is refuted. The results of this study support a rebuttable presumption that PEth ≥20 μg/L is indicative of beverage ethanol consumption. They suggest, however, that intensive, incidental alcohol exposures have the potential, under unusual circumstances, to result in PEth concentrations that modestly exceed this threshold.

Pilot Randomized Controlled Trial of Game Plan for PrEP: A Brief, Web and Text Message Intervention to Help Sexual Minority Men Adhere to PrEP and Reduce Their Alcohol Use

Suboptimal adherence to oral PrEP medications, particularly among younger sexual minority men (SMM), continues to be a key barrier to achieving more substantial declines in new HIV infections. Although variety of interventions, including web and text-message-based applications, have successfully addressed PrEP adherence, very few have addressed the potential influence of alcohol. This pilot study explored whether the Game Plan for PrEP, a brief, web-based and text messaging intervention, helped promote PrEP persistence and adherence and reduced condomless sex and alcohol use. Seventy-three heavy-drinking SMM on PrEP were recruited online from states with Ending the HIV Epidemic jurisdictions and randomly assigned 1:1 to receive either the Game Plan for PrEP intervention or an attention-matched control. We collected online surveys assessing primary outcomes at one, three, and six months post-enrollment. As secondary outcomes, we also collected dried blood spot samples at baseline, three, and six months to analyze for biomarkers of PrEP and alcohol use. Our results showed that the odds of stopping PrEP or experiencing a clinically meaningful lapse in PrEP adherence (≥ 4 consecutive missed doses) were not different across the two conditions. We also did not find evidence of any differences in condomless sex or drinking outcomes across conditions, although participants in both conditions reported drinking less often over time. These findings were consistent across both self-reported outcomes and biomarkers. Overall, we did not find evidence that our brief, web and text messaging intervention encouraged more optimal PrEP coverage or moderate their alcohol use.

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.

Phosphatidylethanol Detects Occult Heavy Alcohol Use in Patients With Acute and Chronic Pancreatitis

Given the paucity of interventions to treat pancreatitis, it is imperative to identify and intervene upon modifiable risk factors such as heavy alcohol use. Current trends indicate a concerning increase in alcohol misuse and alcohol-related disease since the onset of the coronavirus disease-2019 pandemic.1 The incidence of pancreatitis associated with alcohol misuse has increased by approximately 3% annually from 1961 to 2016.2 Alcohol recidivism may be the most important risk factor for pancreatitis recurrence and development of chronic pancreatitis in the United States.3 Early identification of alcohol misuse as a modifiable risk factor is paramount to mitigating pancreatitis-related morbidity. However, blood ethanol and urine ethyl glucuronide levels may be low in symptomatic individuals because they clear rapidly and patients may abstain from drinking in the days before their clinical presentation. Patient self-report may underestimate the quantity of alcohol intake and falsely reassure the provider that this is not a contributing factor to the presentation.4.

The alcohol biomarker phosphatidylethanol (PEth) - test performance and experiences from routine analysis and external quality assessment

Phosphatidylethanol (PEth) are membrane molecules formed from phosphatidylcholine and ethanol through transphosphatidylation catalyzed by phospholipase D. Measurement of the main PEth form 16:0/18:1 is used as a specific and sensitive alcohol biomarker, since its formation requires ethanol, it accumulates in the blood upon repeated ethanol exposure, and it is only slowly eliminated during abstinence. PEth formation correlates with alcohol intake at the population level, albeit with considerable inter-individual variation as for the half-life during withdrawal. Over the past decade, the use of PEth has increased significantly and the applications have broadened. In Sweden, routine decision limits and the interpretation of test results for PEth were harmonized in 2013, using < 0.05 µmol/L (∼35 µg/L) as the recommended lower reporting limit and values > 0.30 µmol/L (∼210 µg/L) to indicate regular high alcohol intake. Routine test results show a large variation with about half being < 0.05 µmol/L and some even exceeding 10 µmol/L. In 2013, an external quality assessment (EQA) scheme for PEth 16:0/18:1 measurement in whole blood was also started (Equalis, Uppsala, Sweden), presently involving 56 laboratories from 13 countries. The agreement of PEth results between the laboratories has gradually improved to a CV < 15%. The current clinical and scientific information suggests that PEth values below the lower reporting limit (typically ∼0.03-0.05 µmol/L, or ∼20-35 µg/L) indicates sobriety or only low or occasional alcohol consumption, while regular high alcohol intake at levels corresponding to harmful drinking is required in most cases to reach PEth values > 0.30 µmol/L.

Role of Biomarkers to Assess the Use of Alcohol

Alcohol-associated liver disease has seen a significant rise in the last 2 decades, with an associated rise in the need for accurate alcohol use assessment. Alcohol use has been associated with poor outcomes in both the pre-liver transplant and post-liver transplant patients. Patients with alcohol use disorder often under-report their alcohol consumption because of varying factors, highlighting the need for objective assessment of alcohol use. Aside from the available self-report questionnaires, multiple serologic biomarkers are currently available to assist clinicians to assess recent alcohol consumption among patients with chronic liver disease, liver transplant candidates, and recipients. In this review, we will assess some of these alcohol biomarkers, discuss their strengths and weakness, and review-available data to discuss their role in pre-liver transplant and post-liver transplant population.

Blood Phosphatidylethanol (PEth) Concentrations following Intensive Use of an Alcohol-based Hand Sanitizer

Alcohol use disorders are prevalent in the USA and throughout the world. Monitoring for alcohol abstinence is useful in several clinical and forensic contexts. The direct alcohol biomarkers have the requisite sensitivity and specificity for abstinence monitoring. The relatively new direct biomarker phosphatidylethanol (PEth), measured in blood, is gaining increasing acceptance in monitoring abstinence from beverage alcohol consumption, but there remains little research addressing the potential for PEth formation consequent to incidental alcohol exposures. In the midst of the coronavirus disease 2019 pandemic, high-alcohol content hand sanitizer is a particularly important source of nonbeverage alcohol exposure. To assess the extent of alcohol absorption and subsequent formation of blood PEth related to intensive use of high alcohol content hand sanitizer, we recruited 15 participants to use a 70% ethyl alcohol-based hand sanitizer 24-100 times daily, for 12-13 consecutive days. Blood was analyzed for PEth 16:0/18:1 by liquid chromatography--tandem mass spectrometry. Our hypothesis that blood PEth concentrations would fail to reach a 20 ng/mL threshold was confirmed. This work adds to the nascent literature on the effects of incidental alcohol exposures on blood PEth formation.

PEth 16:0/18:1 and 16:0/18:2 after consumption of low doses of alcohol-A contribution to cutoff discussion

Phosphatidylethanol in blood has gained recognition as a direct alcohol biomarker. Although different cutoffs have been suggested, there is no consensus for differentiating abstinence from alcohol consumption. In this study, 75 participants (72% female) consumed 20 g of ethanol on three consecutive evenings. Blood was sampled on each following day and PEth 16:0/18:1 and 16:0/18:2 were determined. PEth 16:0/18:1 ranged from 8.9-21.5, 8.7-19.3, and 8.8-42.3 ng/ml and PEth 16:0/18:2 from 8.7-31.7, 9.0-39.3, and 9.4-43.0 ng/ml after the respective days of ethanol consumption. PEth 16:0/18:1 yielded a sensitivity of 25%, 45%, and 49% and PEth 16:0/18:2 of 40%, 61%, and 68% for the consumption days, respectively (cutoff 10 ng/ml). PEth 16:0/18:1 reached >20 ng/ml in five samples overall. Sensitivity of PEth 16:0/18:2 > 20 ng/ml was better with 35% after the three drinking days. Overall, PEth 16:0/18:1 was >35 ng/ml in one sample and PEth 16:0/18:2 in three samples. Significantly, more women had PEth 16:0/18:1 > 10 ng/ml after the third day of consuming 20 g of alcohol (p = 0.02) and PEth 16:0/18:2 > 10 ng/ml after the second (p = 0.023) and the third (p = 0.002) consumption, which can be led back to the higher blood alcohol concentration women reach after consuming the same alcohol amount as men. Although the response rates of PEth to alcohol uptake are subject to strong interindividual differences, results suggest that PEth cutoff should be lowered for better detection of consumption of low to medium amounts of alcohol. Furthermore, it is advantageous to analyze both PEth 16:0/18:2 and 16:0/18:1.

Set-up of a population-based model to verify alcohol abstinence via monitoring of the direct alcohol marker phosphatidylethanol 16:0/18:1

BACKGROUND AND AIMS

Phosphatidylethanol 16:0/18:1 (PEth) is a biomarker for alcohol intake. It has a half-life of 7.9 days. Chronic alcohol consumption causes high PEth values. It can take weeks before PEth values fall below the decision limit for 'alcohol abstinence'. Our aim was to validate whether alcohol abstinence can be determined based on two consecutive PEth results above the decision limit.

DESIGN

Observational study.

SETTING

Belgium, February 2019. The study was linked to a social initiative in Belgium, 'Tournée Minérale'.

PARTICIPANTS

Adults (aged > 18 years, n = 796) with varying drinking habits who self-reportedly refrained from alcohol consumption during the study.

MEASUREMENTS

A validated liquid chromatography-tandem mass spectrometry method was used to quantify PEth in participants' dried blood samples, collected at three time-points via remote fingerprick-based self-sampling.

FINDINGS

A population-based algorithm to evaluate abstinence based on 95% prediction limits was developed by fitting a linear mixed-effect model to discern patterns in PEth elimination over time. It took intra- and inter-individual variability into consideration. The algorithm was included in a two-step decision tree, assessing whether (i) PEth values fell within the prediction interval and (ii) the slope between two PEth values was consistent with no alcohol consumption. Data for 74 participants reporting no alcohol intake during the study were used for validation. With a detection limit of 'four units spread over 14 days', the sensitivity and specificity of the decision tree was 89%.

CONCLUSIONS

Claims of alcohol abstinence can be verified using a two-step decision tree for phosphatidylethanol 16:0/18:1 values, even when those values are above the limit for 'alcohol abstinence'.

Positive blood phosphatidylethanol concentration is associated with unfavorable waitlist-related outcomes for patients medically appropriate for liver transplantation

BACKGROUND

Excessive alcohol use is a leading etiology of liver disease and indication for liver transplantation. Accurate measurement of alcohol use remains a challenge in the management of patients in the pre-, peri-, and post-liver transplant settings. Blood 16:0-18:1 phosphatidylethanol (PEth) concentration is a sensitive and specific biomarker of binge and moderate, chronic alcohol use. As PEth has the longest detection window of available blood-based direct alcohol biomarkers for moderate to heavy drinking, it shows promise as an indicator of patterns and chronicity of drinking. However, the utility of PEth in clinical liver transplantation is understudied. This study examines the association of PEth results with liver transplantation waitlist-focused patient outcomes.

METHODS

Retrospective data for all patients tested for PEth for a one-year period at a tertiary care medical center with an active liver transplantation program were abstracted. Indications for PEth testing, liver transplantation waitlist-related outcomes (e.g., listing and delisting) following testing and associations of PEth results with other parameters were analyzed.

RESULTS

Over a one-year period, 153 PEth tests were performed on 109 individuals. The most frequent indications for PEth testing were as an objective indicator of alcohol use patterns (86.3%) and to assess alcohol as a putative etiology of liver injury (13.7%). Of the 109 patients, 56 were medically appropriate for liver transplantation. Medically acceptable candidates with unfavorable transplantation waitlist-related outcomes (delisting, deferment of transplant evaluation, deferment of listing until completion of recommended alcohol rehabilitation, and being deemed not a transplant candidate) were at least 3.41 times more likely to have a positive PEth test than those with favorable transplantation waitlist-related outcomes (odds ratio 3.41, confidence interval 3.41 to ∞, p = 0.001).

CONCLUSION

This single-center study reporting a comprehensive account of PEth utilization at a liver transplant center demonstrates that liver transplantation waitlist-related outcomes are associated with PEth test results. Patients with positive PEth tests were more likely to have unfavorable transplant waitlist-related outcomes. PEth testing has not been validated as a predictor of relapse to drinking in post-transplant patients and because its utility in the pre-transplant setting is unclear its use could lead to disparities in the selection of patients for liver transplantation.