Ethanol Metabolites: Their Role in the Assessment of Alcohol Intake

Biomarkers of food intake and their relevance to metabolic syndrome

Metabolic syndrome (MetS) constitutes a prevalent risk factor associated with non communicable diseases such as cardiovascular disease and type 2 diabetes. A major factor impacting the etiology of MetS is diet. Dietary patterns and several individual food constituents have been related to the risk of developing MetS or have been proposed as adjuvant treatment. However, traditional methods of dietary assessment such as 24 h recalls rely greatly on intensive user-interaction and are subject to bias. Hence, more objective methods are required for unbiased dietary assessment and efficient prevention. While it is accepted that some dietary-derived constituents in blood plasma are indicators for certain dietary patterns, these may be too unstable (such as vitamin C as a marker for fruits/vegetables) or too broad (e.g. polyphenols for plant-based diets) or reflect too short-term intake only to allow for strong associations with prolonged intake of individual food groups. In the present manuscript, commonly employed biomarkers of intake including those related to specific food items (e.g. genistein for soybean or astaxanthin and EPA for fish intake) and novel emerging ones (e.g. stable isotopes for meat intake or microRNA for plant foods) are emphasized and their suitability as biomarker for food intake discussed. Promising alternatives to plasma measures (e.g. ethyl glucuronide in hair for ethanol intake) are also emphasized. As many biomarkers (i.e. secondary plant metabolites) are not limited to dietary assessment but are also capable of regulating e.g. anti-inflammatory and antioxidant pathways, special attention will be given to biomarkers presenting a double function to assess both dietary patterns and MetS risk.

Modeling social cognition in alcohol use disorder: lessons from schizophrenia

A better understanding of social deficits in alcohol use disorder (AUD) has the potential to improve our understanding of the disorder. Clinical research shows that AUD is associated with interpersonal problems and the loss of a social network which impedes response to treatment. Translational research between animal models and clinical research may benefit from a discussion of the models and methods that currently guide research into social cognition in AUD. We propose that research in AUD should harness recent technological developments to improve ecological validity while maintaining experimental control. Novel methods allow us to parse naturalistic social cognition into tangible components, and to investigate previously neglected aspects of social cognition. Furthermore, to incorporate social cognition as a defining element of AUD, it is critical to clarify the timing of these social disturbances. Currently, there is limited evidence to distinguish factors that influence social cognition as a consequence of AUD, and those that precede the onset of the disorder. Both increasing the focus on operationalization of social cognition into objective components and adopting a perspective that spans the clinical spectrum will improve our understanding in humans, but also possibly increase methodological consistency and translational dialogue across species. This commentary underscores current challenges and perspectives in this area of research.

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.

Monitoring of phosphatidylethanol in dried blood spots and of ethyl glucuronide in hair over 6 months of alcohol consumption

The aim of this study was to monitor seven phosphatidylethanol (PEth) homologues in dried blood spots (DBS) and ethyl glucuronide in hair (EtGH) over a 6-month period of drinking while documenting the daily drinks (amount and type) of alcohol via app. A total of 23 volunteers (12 males and 11 females) aged 19-54 years were enrolled. At four-weekly intervals, capillary blood to create DBS and after 3 and 6 months, respectively, a strand of hair (proximal, 3 cm) was collected. Analyses of EtGH and PEth homologues were performed using liquid chromatography-tandem mass spectrometry. All participants consumed alcohol during the 6 months. Only one participant tested negative for both PEth and EtGH. Eight participants had PEth 16:0/18:1 concentrations between 20 and <210 ng/mL (mean: 45.6 ng/mL) but EtGH concentrations below 5 pg/mg. PEth 16:0/18:1 concentrations between 20 and <210 ng/mL and EtGH concentrations between 5 and <30 pg/mg were assigned to eight subjects, uniformly matching them in the category of socially accepted drinking behavior. Four test subjects exceeded the cutoff for social drinking behavior in both PEth 16:0/18:1 (mean: 528 ng/mL) and EtGH (mean: 84.5 pg/mg). Two participants exceeded the threshold for PEth 16:0/18:1 of 210 ng/mL in blood but remained below 30 pg EtG/mg hair. PEth showed a higher detection rate for alcohol consumption than EtGH did. Moreover, PEth concentrations reacted quickly to changes in drinking behavior, whereas EtGH concentrations remained similar over time.

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.

Gut and bladder fermentation syndromes: a narrative review

We recently reported the first clinical case of bladder fermentation syndrome (BFS) or urinary auto-brewery syndrome, which caused the patient to fail abstinence monitoring. In BFS, ethanol is generated by Crabtree-positive fermenting yeast Candida glabrata in a patient with poorly controlled diabetes. One crucial characteristic of BFS is the absence of alcoholic intoxication, as the bladder lumen contains transitional epithelium with low ethanol permeability. In contrast, patients with gut fermentation syndrome (GFS) or auto-brewery syndrome can spontaneously develop symptoms of ethanol intoxication even without any alcohol ingestion because of alcoholic fermentation in the gut lumen. In abstinence monitoring, a constellation of laboratory findings with positive urinary glucose and ethanol, negative ethanol metabolites, and the presence of yeast in urinalysis should raise suspicion for BFS, whereas endogenous ethanol production needs to be shown by a carbohydrate challenge test for GFS diagnosis. GFS patients will also likely fail abstinence monitoring because of the positive ethanol blood testing. BFS and GFS are treated by yeast eradication of fermenting microorganisms with antifungals (or antibiotics for bacterial GFS cases) and modification of underlying conditions (diabetes for BFS and gut dysbiosis for GFS). The under-recognition of these rare medical conditions has led to not only harm but also adverse legal consequences for patients, such as driving under the influence (DUI). GFS patients may be at risk of various alcohol-related diseases.

Catechol-O-Methyltransferase inhibition and alcohol use disorder: Evaluating the efficacy of tolcapone in ethanol-dependent rats

Alcohol Use Disorder (AUD) is a significant public health issue in the United States. It affects millions of individuals and their families and contributes to substantial societal and economic burdens. Despite the availability of some pharmacological treatments, there is still a pressing need to develop more effective therapeutic strategies to address the diverse range of symptoms and challenges associated with AUD. Catechol-O-methyltransferase (COMT) inhibition recently emerged as a promising new approach to treating AUD due to its potential to improve cognitive effects commonly associated with AUD. Tolcapone, an FDA-approved COMT inhibitor, has shown some promise for treating AUD; however, its ability to decrease drinking in ethanol-dependent rats has not been well-established. In this study, we evaluated the effects of tolcapone on operant, oral ethanol self-administration in non-dependent and dependent rats, and in rats that self-administered oral saccharin. To induce dependence, rats underwent the chronic intermittent exposure to vapor model, and their drinking levels were assessed during acute withdrawal from ethanol. Our results demonstrated that tolcapone attenuated responding for ethanol in dependent rats only, without affecting self-administration in non-dependent rats or rats self-administering saccharin. Moreover, we found that tolcapone was differentially effective in different estrous phases in female rats. These findings suggest that COMT inhibition, specifically using tolcapone, may be a valuable pharmacotherapy for treating AUD, particularly in individuals who are physically dependent on alcohol. Further research is needed to elucidate the precise mechanisms underlying the observed effects and to assess the potential of COMT inhibitors in a broader population of individuals with AUD.

Elimination of matrix effects in urine for determination of ethyl glucuronide by liquid chromatography-tandem mass spectrometry

RATIONALE

Alcohol use disorder affects 4% to 5% of the world's population. Analysis methods are available for various biological fluids to detect this disorder. Determination of ethyl glucuronide in urine by the liquid chromatography-tandem mass spectrometry (LC/MS/MS) method is frequently used in forensic toxicology. These analyses are known to cause matrix effects.

METHODS

The presented study describes the elimination of matrix effects for ethyl glucuronide. This study used two different LC/MS/MS systems containing orthogonal and z-spray ion sources. Ethyl glucuronide was analyzed in negative polarity in electrospray ionization. A different dilution method was chosen for each study. The methods were developed and validated according to the European Medicines Agency bioanalytical method validation parameters.

RESULTS

The lower limit of quantitation of the developed methods was 0.025 μg/mL for ethyl glucuronide. The calibration curve of ethyl glucuronide was between 0.025 and 100 μg/mL with a correlation coefficient of >0.99 for the two methods.

CONCLUSIONS

It was determined that the analyses using the z-spray ion source were more affected by the matrix effect. The two validated methods involve rapid analysis time and simple sample preparation. Also, the methods were applied to real patients' urine.

GPs' experiences of phosphatidylethanol in treatment of hypertension: a qualitative study

BACKGROUND

Hazardous alcohol use increases the risk of hypertension but is underdetected in primary healthcare (PHC) patients. Use of the biomarker phosphatidylethanol (PEth), which reflects the last 2-3 weeks of alcohol consumption, is increasing in Swedish PHC, but studies exploring its use for hypertension are scarce or missing.

AIM

To explore GPs' experiences of using PEth to identify hazardous alcohol use in the context of managing hypertension.

DESIGN & SETTING

A qualitative study of GPs (n = 12) experienced in using PEth in hypertension management who were recruited at Swedish primary healthcare centres (PHCC) in 2021.

METHOD

The GPs participated in five focus group interviews. A questioning route was used. The interviews were audio-recorded, transcribed verbatim, and analysed with inductive qualitative content analysis.

RESULTS

'I don't hesitate anymore' was the overall theme, which reflected both the disappearance of GPs' fear that the PEth result might upset the patient, as this rarely occurred, and that the positive effects of PEth predominated in the findings. The theme is underpinned by the following four sub-themes: serving as an eye-opener; improving the dialogue; using with care; and learning by doing.

CONCLUSION

PEth is a useful tool that changed GPs' routines for addressing alcohol and identifying hazardous alcohol use in patients with hypertension managed in PHC. The GPs advocated adopting PEth as a routine test in the treatment of hypertension. However, PEth needs to be used with care to maximise benefit and minimise harm.

Confounders of Serum Phosphatidylethanol: Role of Red Blood Cell Turnover and Cirrhosis

Purpose

Ethyl glucuronide (EtG), ethyl sulfate (EtS) and phosphatidylethanol (PEth) are considered specific direct biomarkers for detecting alcohol consumption. However, PEth, which is produced in red blood cells (RBC), varies considerably between patients for unknown reasons. We here studied various confounders of PEth elimination including fibrosis after alcohol withdrawal.

Patients and Methods

EtG, EtS and PEth together with routine laboratory and clinical parameters were studied in 100 Caucasian heavy drinkers prior and after alcohol detoxification. In addition, fibrosis stage and degree of steatosis were assessed by transient elastography (Fibroscan, Echosens, Paris).

Results

All three biomarkers were highly correlated (0.61-0.72) with initial serum alcohol levels, but only PEth correlated with daily alcohol consumption. After alcohol withdrawal, PEth significantly decreased within 6.1 days from 1708 to 810 ng/mL (half-life varied from 1.6 to 15.2 days). Both levels of serum alcohol but also EtG and EtS were higher in patients with liver cirrhosis as compared to patients without fibrosis despite comparable alcohol consumption suggesting a decreased alcohol elimination in patients with cirrhosis. PEth was also elevated in cirrhosis but not significantly. In contrast, PEth elimination rate was significantly higher in patients with enhanced RBC turnover and signs of alcohol-mediated hemolytic anemia with elevated ferritin, LDH and increased mean corpuscular volume (MCV).

Conclusion

We here demonstrate that alcohol elimination is decreased in patients with liver cirrhosis. In patients with cirrhosis, PEth levels are both affected in opposite directions by enhanced red blood cell turnover and elevated alcohol levels. Our data have important implications for the use and interpretation of PEth in the clinical setting.

Perspectives on contingency management for alcohol use and alcohol-associated conditions among people in care with HIV

BACKGROUND

Contingency management (CM) is an evidence-based approach for reducing alcohol use; however, its implementation into routine HIV primary care-based settings has been limited. We evaluated perspectives on implementing CM to address unhealthy alcohol use and associated conditions for people with HIV in primary care settings.

METHODS

From May 2021 to August 2021, we conducted two focus groups with staff involved in delivering the intervention (n = 5 Social Workers and n = 4 Research Coordinators) and individual interviews (n = 13) with a subset of participants involved in the multi-site Financial Incentives, Randomization, and Stepped Treatment (FIRST) trial. Qualitative data collection and analyses were informed by the Promoting Action on Research Implementation in Health Service (PARIHS) implementation science framework, including evidence (perception of CM), context (HIV primary care clinic and CM procedures), and facilitation (feasibility outside the research setting).

RESULTS

Several major themes were identified. Regarding the evidence, participants lacked prior experience with CM, but the intervention was well received and, by some, perceived to lead to lasting behavior change. Regarding the clinical context for the reward schedule, the use of biochemical testing, specifically fingerstick phosphatidylethanol testing, and the reward process were perceived to be engaging and gratifying for both staff and patients. Participants indicated that the intervention was enhanced by its co-location within the HIV clinic. Regarding facilitation, participants suggested addressing the intervention's feasibility for non-research use, simplifying the reward structure, and rewarding non-abstinence in alcohol use.

CONCLUSIONS

Among patients and staff involved in a clinical trial, CM was viewed as a helpful, positive, and feasible approach to addressing unhealthy alcohol use and related conditions. To enhance implementation, future efforts may consider simplified approaches to the reward structure and expanding rewards to non-abstinent reductions in alcohol consumption.

Contingency management with stepped care for unhealthy alcohol use among individuals with HIV: Protocol for a randomized controlled trial

BACKGROUND

Although unhealthy alcohol use is associated with increased morbidity and mortality among people with HIV (PWH), many are ambivalent about engaging in treatment and experience variable responses to treatment. We describe the rationale, aims, and study design for the Financial Incentives, Randomization, with Stepped Treatment (FIRST) Trial, a multi-site randomized controlled efficacy trial.

METHODS

PWH in care recruited from clinics across the United States who reported unhealthy alcohol use, had a phosphatidylethanol (PEth) >20 ng/mL, and were not engaged in formal alcohol treatment were randomized to integrated contingency management with stepped care versus treatment as usual. The intervention involved two steps; Step 1: Contingency management (n = 5 sessions) with potential rewards based on 1) short-term abstinence; 2) longer-term abstinence; and 3) completion of healthy activities to promote progress in addressing alcohol consumption or conditions potentially impacted by alcohol; Step 2: Addiction physician management (n = 6 sessions) plus motivational enhancement therapy (n = 4 sessions). Participants' treatment was stepped up at week 12 if they lacked evidence of longer-term abstinence. Primary outcome was abstinence at week 24. Secondary outcomes included alcohol consumption (assessed by TLFB and PEth) and the Veterans Aging Cohort Study (VACS) Index 2.0 scores; exploratory outcomes included progress in addressing medical conditions potentially impacted by alcohol. Protocol adaptations due to the COVID-19 pandemic are described.

CONCLUSIONS

The FIRST Trial is anticipated to yield insights on the feasibility and preliminary efficacy of integrated contingency management with stepped care to address unhealthy alcohol use among PWH.

CLINICALTRIALS

gov identifier: NCT03089320.

Medications for treating alcohol use disorder: A narrative review

Chronic heavy alcohol use impacts all major neurotransmitter systems and is associated with multiple medical, psychiatric, and social problems. Available evidence-based medications to treat alcohol use disorder (AUD) are underutilized in clinical practice. These medications promote abstinence or reduce alcohol consumption, though there are questions regarding their optimal dosage, length of treatment, and utility in combination with one another. Pharmacogenetic approaches, which use a patient's genetic make-up to inform medication selection, have garnered great interest but have yet to yield results robust enough to incorporate them in routine clinical care. This narrative review summarizes the evidence both for medications approved by the Food and Drug Administration (disulfiram, oral naltrexone, acamprosate, and extended-release naltrexone) and those commonly used off-label (e.g., gabapentin, baclofen, and topiramate) for AUD treatment. We discuss these drugs' mechanisms of action, clinical use, pharmacogenetic findings, and treatment recommendations. We conclude that the most consistent evidence supporting the pharmacotherapy of AUD is for the opioid antagonists, naltrexone and nalmefene (which is not approved in the United States), and topiramate. These medications demonstrate consistent small or moderate effects in reducing the frequency of drinking and/or heavy drinking. Lastly, we make suggestions for research needed to refine and expand the current literature on effective pharmacotherapy for AUD.

Predictive risk markers in alcoholism

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

Spectrum, Screening, and Diagnosis of Alcohol-related Liver Disease

Alcohol-related liver disease (ALD) represents one of the leading causes of chronic liver disease and is a major cause of liver-related deaths worldwide. ALD encompasses a range of disorders including simple steatosis, alcoholic steatohepatitis, fibrosis, cirrhosis, and hepatocellular carcinoma. Patients with underlying ALD and continued heavy alcohol consumption can also develop an episode of acute-on-chronic liver injury called alcohol-associated hepatitis, the most severe form of the disease, which portends a poor prognosis. The most important risk factor for the development of ALD is the amount of alcohol consumed. Individual susceptibility to progression to advanced fibrosis among heavy drinkers is likely determined by a combination of behavioral, environmental, genetic, and epigenetic factors, but the mechanisms are largely unknown. The only effective therapy for ALD is prolonged alcohol abstinence. Diagnosis of ALD involves assessing patients for alcohol use disorder and signs of advanced liver disease. In clinical practice, the histological assessment for ALD diagnosis is uncommon, and it is usually based on the medical history, clinical manifestations, and laboratory and imaging tests. Several promising biomarkers that can have both diagnostic and prognostic value in patients with ALD have been identified in recent years. This review provides an overview of the clinical spectrum of ALD, the diagnostic approach of the disease from different perspectives as well as current diagnostic and prognostic biomarkers.

Association of topiramate prescribed for any indication with reduced alcohol consumption in electronic health record data

BACKGROUND AND AIMS

Topiramate is a medication that is widely prescribed to treat a variety of conditions, including alcohol use disorder (AUD). We used electronic health record (EHR) data to measure topiramate's effects on drinking in individuals differentiated by a history of AUD.

DESIGN

Parallel-groups comparison of patients prescribed topiramate and a propensity score-matched comparison group.

SETTING

A large US integrated health-care system.

PARTICIPANTS

Patients with Alcohol Use Disorders Identification Test-Consumption (AUDIT-C) scores prior to and after a minimum of 180 days of topiramate prescription for any indication and a propensity score-matched group. The sample included 5918 patients with an electronic health record diagnosis of alcohol use disorder at any time (AUD-hx-pos) (1738 topiramate-exposed and 4180 controls) and 23 614 patients with no EHR diagnosis of AUD (AUD-hx-neg) (6324 topiramate-exposed and 17 290 controls).

MEASUREMENTS

Regression analyses compared difference-in-difference (DiD) estimates, separately by AUD history. DiD estimates represent exposure-group (i.e. topiramate versus control) differences on the pre-post difference in AUDIT-C score. Effects of baseline AUDIT-C score and daily topiramate dosage were also tested.

FINDINGS

AUD-hx-neg patients who received topiramate had a greater reduction in AUDIT-C score (-0.11) than matched controls (-0.04). This yielded a DiD score of -0.07 [95% confidence interval (CI) = -0.11,-0.03; P = 0.002], with the greatest effect among AUD-hx-neg patients with a baseline AUDIT-C score of 4+ (DiD = -0.35, 95% CI = -0.49, -0.21; P < 0.0001) and those prescribed > 150 mg/day of the medication (DiD = -0.15, 95%CI = -0.23, -0.07; P < 0.001).

DISCUSSION

Among individuals with no history of alcohol use disorder, topiramate appears to be associated with reduced drinking. This small effect is most evident among patients with higher baseline drinking levels and at a higher average daily topiramate dosage.

Alcoholic liver disease: a new insight into the pathogenesis of liver disease

Excessive alcohol consumption contributes to a broad clinical spectrum of liver diseases, from simple steatosis to end-stage hepatocellular carcinoma. The liver is the primary organ that metabolizes ingested alcohol and is exquisitely sensitive to alcohol intake. Alcohol metabolism is classified into two pathways: oxidative and non-oxidative alcohol metabolism. Both oxidative and non-oxidative alcohol metabolisms and their metabolites have toxic consequences for multiple organs, including the liver, adipose tissue, intestine, and pancreas. Although many studies have focused on the effects of oxidative alcohol metabolites on liver damage, the importance of non-oxidative alcohol metabolites in cellular damage has also been discovered. Furthermore, extrahepatic alcohol effects are crucial for providing additional information necessary for the progression of alcoholic liver disease. Therefore, studying the effects of alcohol-producing metabolites and interorgan crosstalk between the liver and peripheral organs that express ethanol-metabolizing enzymes will facilitate a comprehensive understanding of the pathogenesis of alcoholic liver disease. This review focuses on alcohol-metabolite-associated hepatotoxicity due to oxidative and non-oxidative alcohol metabolites and the role of interorgan crosstalk in alcoholic liver disease pathogenesis.

Management of alcohol-related liver disease: the French Association for the Study of the Liver and the French Alcohol Society clinical guidelines

Excessive alcohol consumption is the leading cause of liver diseases in Western countries, especially in France. Alcohol-related liver disease (ARLD) is an extremely broad context and there remains much to accomplish in terms of identifying patients, improving prognosis and treatment, and standardising practices. The French Association for the Study of the Liver wished to organise guidelines together with the French Alcohol Society in order to summarise the best evidence available about several key clinical points in ARLD. These guidelines have been elaborated based on the level of evidence available in the literature and each recommendation has been analysed, discussed and voted by the panel of experts. They describe how patients with ARLD should be managed nowadays and discuss the main unsettled issues in the field.

Development and Validation of a GC-EI-MS/MS Method for Ethyl Glucuronide Quantification in Human Hair

Ethyl glucuronide (EtG) is a minor, non-oxidative ethanol metabolite detectable in several matrices for specific periods of time. In recent years, quantification of EtG in hair has been established as the most reliable biomarker for long-term alcohol consumption, with the Society of Hair Testing offering cut-off values for assessment of both abstinence and heavy drinking. Instrumental constrains and wide inter- and intra-laboratory variability represent the ultimate barriers to widespread acceptance of hair EtG determination in the forensic context. In this study, a new analytical method for hair EtG based on gas chromatographic (GC) separation, electron impact (EI) ionization, and tandem mass spectrometry (MS/MS) detection was developed and validated. At the same time, several parameters for sample pretreatment and instrumental analysis were optimized using real hair samples obtained from different drinking subjects. A full-factorial design-of-experiment approach included procedures for hair washing, pulverization, and extraction. Rigorous multi-step washing proved not to reduce the EtG content extracted in the subsequent sample incubation. Hair pulverization with a ball mill significantly improved the EtG extraction from the keratin matrix and allowed us to reduce the time needed for the subsequent extraction step, without affecting the extraction recovery. The hair extract was derivatized with N-methyl-N-(trimethylsilyl)-trifluoroacetamide. Upon electron impact ionization of the EtG-TMS derivative, triple quadrupole mass analyzers were operated in the selected reaction monitoring (SRM) mode using the fragment m/z 405 as the precursor ion (m/z 410 for the EtG-D5 internal standard), the transitions m/z 405 → 359 and m/z 410 → 359 for quantitation, and m/z 405 → 331 and m/z 405 → 287 for qualification/confirmation, all at 10 V collision energy. The final method was fully validated and then applied to 25 real hair samples. The calibration curve proved linear between 6 and 60 pg/mg. The limit of detection (LOD) was 4 pg/mg. Intra- and inter-assay precision and accuracy tests showed a variability and bias close to 15% or lower over the entire calibration range. The new method is routinely applied in the Italian State Police’s toxicology laboratory for hair analyses addressed to exclude excessive alcohol drinking and verify the psycho-physical requirements of the personnel.

Change in Alcohol Use Based on Self-Report and a Quantitative Biomarker, Phosphatidylethanol, in People With HIV

The timeline followback (TLFB) takes more resources to collect than the Alcohol Use Disorder Identification Test (AUDIT-C). We assessed agreement of TLFB and AUDIT-C with the biomarker phosphatidylethanol (PEth) and compared changes in TLFB and PEth among persons with HIV (PWH) using secondary data from randomized trials. We calculated operating characteristics and agreement between TLFB (> 1 and > 2 average drinks/day), AUDIT-C ≥ 4 and PEth ≥ 20 among 275 men with HIV. Median age was 57 years, 80% were African-American; and 17% white. Sixty-eight percent had PEth ≥ 20, 46% reported > 2 average drinks/day on TLFB, 61% reported > 1 average drinks/day on TLFB, and 72% had an AUDIT-C ≥ 4. Relative to PEth, sensitivity for AUDIT-C ≥ 4 was 84% (kappa = 0.36), and for TLFB > 1 average drink/day was 76% (kappa = 0.44). Change in alcohol use appeared greater using TLFB measures than PEth. Strategies to robustly assess alcohol use in PWH may require both self-report and biomarkers.

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.

Computer delivered intervention for alcohol and sexual risk reduction among women attending an urban sexually transmitted infection clinic: A randomized controlled trial

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Unhealthy alcohol use is prevalent among women attending STI clinics.

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We tested whether CBI or CBI-IVR-TM, reduced alcohol use among women in this setting.

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Neither CBI nor CBI-IVR-TM reduced alcohol use more than control.

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2/3 of women had an alcohol use disorder, 65% substance use, 28% depressive symptoms.

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CBI is insufficient for alcohol reduction in this high severity, high comorbidity setting.

Objective

We sought to determine if a computer delivered brief alcohol intervention (CBI) with or without interactive voice response counseling and text messages (CBI-IVR-TM), reduced alcohol use and sexual risk behaviors compared to attention control.

Methods

We conducted a 3-arm RCT among women (n = 439) recruited from Baltimore City Sexually Transmitted Infection (STI) Clinics. Eligibility included: 1) consumption of >7 drinks per week or 2) ≥2 episodes of heavy episodic drinking or ≥2 episodes of sex under the influence of alcohol in the prior three months. Research assessments conducted at baseline, 3, 6 and 12 months included a 30-day Timeline Followback querying daily alcohol use, drug use, and sexual activity. We used the MINI International Neuropsychiatric Interview-DSM-IV to ascertain drinking severity. Primary alcohol outcomes included: drinking days, heavy drinking days, drinks per drinking day. Secondary sexual risk outcomes included number of sexual partners, days of condomless sex, and days of condomless sex under the influence of drugs and alcohol.

Results

Median age was 31 (IQR 25–44 years), 88% were African American, 65% reported current recreational drug use, and 26% endorsed depressive symptoms. On the MINI 66% met criteria for alcohol use disorder (49% alcohol dependence, 18% abuse). At follow-up, all three groups reduced drinking days, heavy drinking days, drinks per drinking day and drinks per week with no significant differences between study arms. There was no difference in sexual risk outcomes among the groups.

Conclusions

 Among women attending an urban STI clinic single session CBI with or without IVR and text message boosters was insufficient to reduce unhealthy alcohol use or sexual risk behaviors beyond control. The high severity of alcohol use and the prevalence of mental health symptoms and other substance use comorbidity underscores the importance of developing programs that address not only alcohol use but other determinants of STI risk among women.

Research Needs for Inpatient Management of Severe Alcohol Withdrawal Syndrome: An Official American Thoracic Society Research Statement

Background: Severe alcohol withdrawal syndrome (SAWS) is highly morbid, costly, and common among hospitalized patients, yet minimal evidence exists to guide inpatient management. Research needs in this field are broad, spanning the translational science spectrum. Goals: This research statement aims to describe what is known about SAWS, identify knowledge gaps, and offer recommendations for research in each domain of the Institute of Medicine T0-T4 continuum to advance the care of hospitalized patients who experience SAWS. Methods: Clinicians and researchers with unique and complementary expertise in basic, clinical, and implementation research related to unhealthy alcohol consumption and alcohol withdrawal were invited to participate in a workshop at the American Thoracic Society 2019 International Conference. The committee was subdivided into four groups on the basis of interest and expertise: T0-T1 (basic science research with translation to humans), T2 (research translating to patients), T3 (research translating to clinical practice), and T4 (research translating to communities). A medical librarian conducted a pragmatic literature search to facilitate this work, and committee members reviewed and supplemented the resulting evidence, identifying key knowledge gaps. Results: The committee identified several investigative opportunities to advance the care of patients with SAWS in each domain of the translational science spectrum. Major themes included 1) the need to investigate non-γ-aminobutyric acid pathways for alcohol withdrawal syndrome treatment; 2) harnessing retrospective and electronic health record data to identify risk factors and create objective severity scoring systems, particularly for acutely ill patients with SAWS; 3) the need for more robust comparative-effectiveness data to identify optimal SAWS treatment strategies; and 4) recommendations to accelerate implementation of effective treatments into practice. Conclusions: The dearth of evidence supporting management decisions for hospitalized patients with SAWS, many of whom require critical care, represents both a call to action and an opportunity for the American Thoracic Society and larger scientific communities to improve care for a vulnerable patient population. This report highlights basic, clinical, and implementation research that diverse experts agree will have the greatest impact on improving care for hospitalized patients with SAWS.

Classical blood biomarkers identify patients with higher risk for relapse 6 months after alcohol withdrawal treatment

This naturalistic study among patients with alcohol dependence examined whether routine blood biomarkers could help to identify patients with high risk for relapse after withdrawal treatment. In a longitudinal study with 6-month follow-up among 133 patients with alcohol dependence who received inpatient alcohol withdrawal treatment, we investigated the usefulness of routine blood biomarkers and clinical and sociodemographic factors for potential outcome prediction and risk stratification. Baseline routine blood biomarkers (gamma-glutamyl transferase [GGT], alanine aminotransferase [ALT/GPT], aspartate aminotransferase [AST/GOT], mean cell volume of erythrocytes [MCV]), and clinical and sociodemographic characteristics were recorded at admission. Standardized 6 months' follow-up assessed outcome variables continuous abstinence, days of continuous abstinence, daily alcohol consumption and current abstinence. The combined threshold criterion of an AST:ALT ratio > 1.00 and MCV > 90.0 fl helped to identify high-risk patients. They had lower abstinence rates (P = 0.001), higher rates of daily alcohol consumption (P < 0.001) and shorter periods of continuous abstinence (P = 0.027) compared with low-risk patients who did not meet the threshold criterion. Regression analysis confirmed our hypothesis that the combination criterion is an individual baseline variable that significantly predicted parts of the respective outcome variances. Routinely assessed indirect alcohol biomarkers help to identify patients with high risk for relapse after alcohol withdrawal treatment. Clinical decision algorithms to identify patients with high risk for relapse after alcohol withdrawal treatment could include classical blood biomarkers in addition to clinical and sociodemographic items.

World Health Organization risk drinking levels as a treatment outcome measure in topiramate trials

BACKGROUND

Although abstinence has traditionally been considered the only suitable outcome for alcohol treatment, reduced drinking is also associated with improved functioning and medical and psychiatric outcomes. The World Health Organization (WHO) risk drinking levels (RDLs) have been shown to be valid outcome measures in treatment trials for alcohol use disorder (AUD).

METHODS

We conducted a secondary analysis of two 12-week, randomized controlled trials (RCTs), in which a total of 308 individuals with problematic alcohol use received topiramate or placebo treatment. We compared the utility of the WHO RDLs with other treatment outcomes, including self-reported measures of alcohol consumption, alcohol-related problems, and quality of life, and the biomarker gamma-glutamyltransferase.

RESULTS

Topiramate treatment was associated with small effect sizes for both a 1-level (d = 0.26) and a 2-level (d = 0.19) reduction in WHO RDL, effects that were not significant after correction for multiple comparisons. No heavy drinking days, one of the outcome measures recommended by the US Food and Drug Administration for alcohol medication registration trials, also exhibited a small effect (0.21), while an effect size for abstinence could not be calculated. There were medium effects of topiramate on continuous measures of percent heavy drinking days (d = 0.49) and alcohol-related problems (d = 0.41).

CONCLUSIONS

Topiramate is an efficacious pharmacotherapy for AUD. Although continuous measures of drinking and alcohol-related problems yielded larger effect sizes than the WHO RDLs, the latter nonetheless provide a categorical alternative for use in both clinical care and pharmacotherapy trials.

Combined analysis of the moderating effect of a GRIK1 polymorphism on the effects of topiramate for treating alcohol use disorder

BACKGROUND

In an initial study, we reported that topiramate reduced heavy drinking among individuals who sought to reduce their drinking and that the effect was moderated by a single nucleotide polymorphism (SNP; rs2832407) in GRIK1, which encodes the kainate GluK1 receptor subunit (Kranzler et al., 2014). In a subsequent study that prospectively randomized patients to medication group based on their rs2832407 genotype, we replicated the main effect of topiramate but not the moderating effect of the SNP (Kranzler et al., 2021). Given the similar design of the two studies, here we combined the findings to provide greater statistical power to test the pharmacogenetic effect.

MATERIAL AND METHODS

This secondary analysis of two 12-week, randomized controlled trials of topiramate included a total of 292 European-ancestry individuals (67.1 % male; topiramate: 48.3 %, placebo: 51.7 %) with problematic alcohol use. Using MANOVA, we examined changes in self-reported alcohol consumption, problems resulting from alcohol use, and quality of life, and the biomarker γ-glutamyltransferase. To test the pharmacogenetic hypothesis, all patients were genotyped for rs2832407.

RESULTS

There was a significant overall effect of topiramate on the alcohol-related outcomes (partial η2 = 0.134, p < 0.001), with follow-up analyses showing significant reductions in percent heavy drinking days (Cohen's d = 0.49), percent days abstinent (d = 0.23), drinks/day (d = 0.29) and alcohol-related problems (d = 0.45). Overall, the moderating effect of the SNP was non-significant (partial η² = 0.026, p = 0.37).

CONCLUSIONS

Although topiramate is an efficacious medication for reducing drinking and alcohol-related problems among patients with problematic alcohol use, rs2832407 does not appear to moderate its therapeutic effects. www.clinicaltrials.gov registrations: NCT00626925 and NCT02371889.

Direct Alcohol Biomarkers Prediction Capacity on Relapse and Mortality in Liver Transplantation Candidates: A Follow-Up Study

Liver transplantation is a complex procedure that requires multiple evaluations, including abstinence monitorization. While literature assessing the impact of different variables on relapse, survival, and graft loss exists, little is known about the predictive capacity of direct alcohol biomarkers. The primary aim of this study was to evaluate the prediction capacity of direct alcohol biomarkers regarding patient survival and clinical relapse. We hypothesized that patients screening positive for any of the experimental biomarkers would show an increased risk of clinical alcohol relapse and death. We conducted a retrospective data recollection from medical files of patients awaiting liver transplantation, who were at baseline screened with Peth, EtG in hair and urine, and EtS. We tested the prediction capacity of the biomarkers with two Cox-regression models. A total of 50 patients were included (84% men, mean age 59 years (SD = 6)). Biomarkers at baseline were positive in 18 patients. The mean follow-up time for this study was 26 months (SD = 10.4). Twelve patients died, liver transplantation was carried out in 12 patients, and clinical relapse was observed in eight patients. The only significant covariate in the Cox-regression models was age with clinical relapse, with younger patients being at greater risk of relapse. This study could not find a significant prediction capacity of direct alcohol biomarkers for mortality or clinical relapse during follow-up. Higher sample sizes might be needed to detect statistically significant differences. All in all, we believe that direct alcohol biomarkers should be widely used in liver transplantation settings due to their high sensitivity for the detection of recent drinking.

Wrist-worn alcohol biosensors: Applications and usability in behavioral research

Wrist-worn alcohol biosensor technology has developed rapidly in recent years. These devices are light, easy to wear, relatively inexpensive, and resemble commercial fitness trackers. As a result, they may be more suitable for a wide range of clinical and research applications. In this paper, we describe three pilot projects examining the associations between reported drinking behavior and transdermal alcohol concentration (TAC) derived from a new, wrist-worn alcohol biosensor (BACtrack Skyn) in diverse participant groups and settings. Study 1 (N = 3) compared Skyn-derived TAC with that from an ankle-worn alcohol sensor (SCRAM CAM) and breath alcohol concentration (BrAC) in a laboratory setting. Study 2 (N = 10) compared Skyn TAC with BrAC during a naturalistic drinking episode in the field. Study 3 (N = 12) used the Skyn to monitor alcohol use in the field for 2 weeks. Studies 2 and 3 also collected usability and acceptability data from participants. The results of Study 1 showed that the Skyn produced a TAC curve that closely resembled that of the validated SCRAM CAM anklet. In Study 2, Skyn detected drinking for all 10 participants (peak BrAC range: 0.02-0.21) with an average delay of 35.6 ± 10.2 min after the start of self-reported drinking. In Study 3, Skyn reliably recorded continuous TAC data showing multiple drinking episodes over the monitoring period. Participants in Studies 2 and 3 both reported Skyn as highly acceptable. Collectively, the results of these pilot studies show that the Skyn was able to reliably detect drinking events in the laboratory and natural environments. We offer suggestions for further refinements of alcohol biosensors and accompanying analytic software that may facilitate adoption of these devices as cost-effective, user-friendly, and reliable tools to passively and accurately assess alcohol use in the field.

Abstinence Among Alcohol Use Disorder Patients During the COVID-19 Pandemic: Insights From Spain

BACKGROUND

Patients with alcohol use disorder (AUD) are likely to suffer disproportionate harms related to the COVID-19 pandemic and related policy measures. While many surveys have been conducted, most are focused on drinking changes in the general population and validation with biological markers is lacking.

METHOD

We performed a retrospective cohort study among patients with AUD attending a urine drug screening program. With mixed-effects logistic regression models, we assessed the probability of screening positive for ethyl glucuronide according to patients' main clinical characteristics and time of analysis (either prior to or after a lockdown was implemented in Spain).

RESULTS

A total of 362 patients provided 2,040 urine samples (1,295 prior to lockdown, 745 during lockdown). The mean age of participants was 52.0 years (SD 12.6), and 69.2% were men. Of the 43% of patients tested for other drugs 22% screened positive. After adjusting for all covariates, the odds of screening positive for ethyl glucuronide during lockdown almost doubled (OR = 1.99, 95% CI 1.20 to 3.33, p = 0.008). Other significant covariates included testing positive for other drugs (OR = 10.79, 95% CI 4.60 to 26.97) and length of treatment (OR = 0.59, 95% CI 0.47 to 0.74).

CONCLUSIONS

Our data support an association between the lockdown due to COVID-19 and increased alcohol use in patients with AUD. Thus, addiction healthcare systems could face significant challenges ahead. In light of these findings, it is essential to evaluate prospectively how patients with AUD are affected by the pandemic and how health systems respond to their needs.

Ethyl Glucuronide and Ethyl Sulphate in Urine: Caution in their use as markers of recent alcohol use

AIM

To clarify the role of the ethanol metabolites, ethyl glucuronide (EtG) and ethyl sulfate (EtS), in monitoring alcohol consumption.

METHOD

We recruited 7 female and 17 male volunteers who were instructed to consume a quantity of beer (containing 48 gm ethanol) with food in one session. We examined urinary excretion of EtG and EtS over time and looked for correlations between the concentrations of the metabolites EtG and EtS.

RESULTS

EtG concentrations in urine varied between 0.026 and 430.372 μg/ml with average values between 11.85 μg/ml (SD 19.75), 30 min after alcohol intake, and 100.39 μg/ml (SD 101.34), 4.5 h after alcohol intake. EtS urinary concentration ranged from 0.006 to 101.432 μg/ml with average values between 4.77 μg/ml (SD 5.42), 30 min after alcohol intake, and 30.14 μg/ml (SD 27.20), 4.5 h after alcohol intake. Spearman's test showed that urinary EtG and EtS correlated significantly at several time points.

CONCLUSION

The great interindividual variability in their excretion suggests caution in the use of urinary measurement of these metabolites in forensic investigations.

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.

Diagnostic Accuracy of Biomarkers of Alcohol Use in Patients With Liver Disease: A Systematic Review

BACKGROUND AND AIMS

Alcohol-related liver disease is the most frequent cause of cirrhosis and a major indication for liver transplantation. Several alcohol use biomarkers have been developed in recent years and are already in use in several centers. However, in patients with liver disease their diagnostic performance might be influenced by altered biomarker formation by hepatic damage, altered excretion by kidney dysfunction and diuretics use, and altered deposition in hair and nails. We systematically reviewed studies on the diagnostic accuracy of biomarkers of alcohol use in patients with liver disease and performed a detailed study quality assessment.

METHODS

A structured search in PubMed/Medline/Embase databases was performed for relevant studies, published until April 28, 2019. The risk of bias and applicability concerns was assessed according to the adapted quality assessment of diagnostic accuracy studies-2 (QUADAS-2) checklist.

RESULTS

Twelve out of 6,449 studies met inclusion criteria. Urinary ethyl glucuronide and urinary ethyl sulfate showed high sensitivity (70 to 89 and 73 to 82%, respectively) and specificity (93 to 99 and 86 to 89%, respectively) for assessing any amount of alcohol use in the past days. Serum carbohydrate-deficient transferrin showed low sensitivity but higher specificity (40 to 79 and 57 to 99%, respectively) to detect excessive alcohol use in the past weeks. Whole blood phosphatidylethanol showed high sensitivity and specificity (73 to 100 and 90 to 96%, respectively) to detect any amount of alcohol use in the previous weeks. Scalp hair ethyl glucuronide showed high sensitivity (85 to 100%) and specificity (97 to 100%) for detecting chronic excessive alcohol use in the past 3 to 6 months. Main limitations of the current evidence are the lack of an absolute gold standard to assess alcohol use, heterogeneous study populations, and the paucity of studies.

CONCLUSIONS

Urinary and scalp hair ethyl glucuronide are currently the most validated alcohol use biomarkers in patients with liver disease with good diagnostic accuracies. Phosphatidylethanol is a highly promising alcohol use biomarker, but so far less validated in liver patients. Alcohol use biomarkers can complement each other regarding diagnostic time window. More validation studies on alcohol use biomarkers in patients with liver disease are needed.

Quantitative determination of phosphatidylethanol in dried blood spots for monitoring alcohol abstinence

Phosphatidylethanol (PEth), which is formed by enzymatic reaction between ethanol and phosphatidylcholine, is a direct marker for alcohol usage. PEth has a long elimination half-life (~5-10 d) and specimens can be sampled using minimally invasive microsampling strategies. In combination with rapid analysis procedures PEth has proved to be advantageous for the detection of abstinence over other direct (e.g., ethyl glucuronide in blood, urine or hair) and indirect (e.g., carbohydrate-deficient transferrin in serum) alcohol markers. Although PEth determination is widely applied around the world, laboratory protocols are not standardized. Here we provide general guidelines for the analysis of PEth in dried blood spots (DBSs), including reference material evaluation, synthesis of a deuterated internal standard, preparation of calibration samples (reference material in teetotaller blood), and analyte separation and detection. The protocol contains information to extract the DBSs either manually or with a fully automated autosampler. Extraction of the analytes from DBS filter paper cards is performed using an organic extraction, followed by liquid chromatography coupled to tandem mass spectrometry (LC-MS/MS). For accurate and reliable measurement of PEth, the two most abundant analogs, PEth 16:0/18:1 and PEth 16:0/18:2, are quantified. We show data that provide guidelines on how to interpret the results for both demographic studies and forensic applications. The described protocol can be applied by experienced laboratory staff with basic LC-MS/MS knowledge and takes 2 d to perform.

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.

Phosphatidylethanol for Monitoring Alcohol Use in Liver Transplant Candidates: An Observational Study

Liver transplantation remains an essential procedure for many patients suffering from alcoholic liver disease. Alcohol use monitoring remains paramount all through the stages of this complex process. Direct alcohol biomarkers, with improved specificity and sensibility, should replace traditional indirect markers. Phosphatidylethanol (PEth) has been recently tested in alcoholic liver disease patients, but more evidence is needed, especially in comparison with other direct biomarkers. We conducted an observational study among patients awaiting liver transplantation. We analyzed Peth in blood, ethylglucuronide (EtG) in hair and urine and ethylsulphate (EtS) in urine, using mass spectrometry methods. In addition, transaminases, and self-reports were analyzed. A total of 50 patients were included (84% men, mean age 59 years (SD = 6)). 18 patients (36%) screened positive for any marker. Self-reports were positive in 3 patients. EtS was the biomarker with more positive screens. It also was the most frequently exclusive biomarker, screening positive in 7 patients who were negative for all other biomarkers. PEth was positive in 5 patients, being the only positive biomarker in 2 patients. It showed a false negative in a patient admitting alcohol use the previous week and screening positive for EtG and EtS. Hair EtG was positive in 3 patients who had negative Peth, EtG. EtG did not provide any exclusive positive result.A combination of biomarkers seems to be the best option to fully ascertain abstinence in this population. Our study suggest EtS might also play a significant role.

Estimating alcohol consumption by using wastewater-based epidemiology in Adana Province, Turkey

Increased alcohol consumption, especially among young people, is a major concern in Turkey as it is around the world due to negative effects on public health and safety. Regarding this, it is pivotal to monitor and therefore control alcohol use in public. In this case, wastewater-based epidemiology (WBE), which is the in-depth analysis of wastewater and a relatively new method, can deliver complementary information concerning the abuse of different substances. The proven potential of the WBE approach offers new promises in the process of monitoring alcohol use, namely the monitoring of the levels of ethyl sulfate (EtS) as a urinary biomarker of alcohol consumption, and it is a powerful mean to estimate alcohol use at the community level. In this study, raw 24-h composite wastewater samples were collected from Seyhan and Yüregir wastewater treatment plants (WWTPs) in Adana Province for one week per season (October 2016-August 2017). The fast and validated analytical method was performed by liquid chromatography coupled to tandem mass spectrometry (LC-MS/MS) and therefore applied to the analysis of ethyl sulfate (EtS). Obtained concentration values were back-calculated, and regional and temporal social usage rates were determined. Higher values were calculated for both WWTPs on Sunday. Alcohol consumption in the region served by Seyhan WWTP was higher than Yüregir WWTP. The results showed that the levels of alcohol consumption during given periods in Adana ranged from 659.8 to 8998.7 mL/day/1000 per person with an average value of 4983.9 and 3924.2 mL/day/1000 inhabitant in Seyhan WWTP and Yüregir WWTP, respectively. This study shows that weekly and annual trends in alcohol consumption can be detected quickly from wastewater analysis.

Systematic review and meta-analysis of the moderating effect of rs1799971 in OPRM1, the mu-opioid receptor gene, on response to naltrexone treatment of alcohol use disorder

BACKGROUND AND AIMS

There is wide inter-individual variability in response to the treatment of alcohol use disorder (AUD) with the opioid receptor antagonist naltrexone. To identify patients who may be most responsive to naltrexone treatment, studies have examined the moderating effect of rs1799971, a single nucleotide polymorphism (SNP) that encodes a non-synonymous substitution (Asn40Asp) in the mu-opioid receptor gene, OPRM1. The aims of this study were to: (1) conduct a systematic review of randomized clinical trials (RCTs); (2) assess the bias of the available studies and gauge publication bias; and (3) meta-analyze the interaction effect of the Asn40Asp SNP on the response to naltrexone treatment.

METHODS

We searched for placebo-controlled RCTs that examined the effect of Asn40Asp on the response to naltrexone treatment of heavy drinking or AUD. We tested the hypothesis that the minor (Asp40) allele was associated with a greater reduction in five alcohol consumption measures (relapse to heavy drinking, abstinence, percentage of heavy drinking days, percentage of days abstinent and drinks per day) in naltrexone-treated participants by meta-analyzing the interaction effects using a random effects model.

RESULTS

Seven RCTs met the study criteria. Overall, risk of bias was low and we observed no evidence of publication bias. Of the five alcohol consumption outcomes considered, there was a nominally significant moderating effect of the Asn40Asp SNP only on drinks per day (d = -0.18, P = 0.02). However, the effect was not significant when multiple comparisons were taken into account.

CONCLUSIONS

From the evidence to date, it remains unclear whether rs1799971, the OPRM1 Asn40Asp single nucleotide polymorphism, predicts naltrexone treatment response in individuals with alcohol use disorder or heavy drinking.

Persistent Urinary Ethyl Sulfate in the Absence of Urinary Ethyl Glucuronide in a Patient with Alcohol Use Disorder Who Claimed Abstinence

A 48-year-old nurse with an alcohol use disorder history was being monitored in a professional health program. She consistently produced low-to-moderate urinary ethyl sulfate (EtS) concentrations in the absence of detectable urinary ethyl glucuronide (EtG), blood phosphatidylethanol and breath alcohol. She denied intentional ethanol consumption. After prolonged monitoring in a drug treatment program, including a period in a controlled environment, we concluded that this individual's urinary EtS likely resulted from anatomical and microbial factors related to Roux-en-Y gastric bypass surgery, with possible contributions from hidden dietary sources of ethanol. We have no definitive explanation for the lack of urinary EtG.

Integrated stepped alcohol treatment for patients with HIV and at-risk alcohol use: a randomized trial

BACKGROUND

At-risk levels of alcohol use threaten the health of patients with HIV (PWH), yet evidence-based strategies to decrease alcohol use and improve HIV-related outcomes in this population are lacking. We examined the effectiveness of integrated stepped alcohol treatment (ISAT) on alcohol use and HIV outcomes among PWH and at-risk alcohol use.

METHODS

In this multi-site, randomized trial conducted between January 28, 2013 through July 14, 2017, we enrolled PWH and at-risk alcohol use [defined as alcohol consumption of ≥ 14 drinks per week or ≥ 4 drinks per occasion in men ≤ 65 years old or ≥ 7 drinks per week or ≥ 3 drinks per occasion in women or men > 65 years old]. ISAT (n = 46) involved: Step 1- Brief Negotiated Interview with telephone booster, Step 2- Motivational Enhancement Therapy, and Step 3- Addiction Physician Management. Treatment as usual (TAU) (n = 47) involved receipt of a health handout plus routine care. Analyses were conducted based on intention to treat principles.

RESULTS

Despite a multi-pronged approach, we only recruited 37% of the target population (n = 93/254). Among ISAT participants, 50% advanced to Step 2, among whom 57% advanced to Step 3. Participants randomized to ISAT and TAU had no observed difference in drinks per week over the past 30 days at week 24 (primary outcome) [least square means (Ls mean) (95% CI) = 8.8 vs. 10.6; adjusted mean difference (AMD) (95% CI) =  - 0.4 (- 3.9, 3.0)].

CONCLUSION

An insufficient number of patients were interested in participating in the trial. Efforts to enhance motivation of PWH with at-risk alcohol use to engage in alcohol-related research and build upon ISAT are needed. Trial registration Clinicaltrials.gov: NCT01410123, First posted August 4, 2011.

Sensitivity and specificity of a commercial urinary ethyl glucuronide (ETG) test in heavy drinkers

Introduction

To advance the use of alcohol metabolites as biomarkers in the context of alcohol research, the present study tested the sensitivity and specificity of a commercially available urinary ethyl glucuronide (uEtG) test (DrugConfirm Advanced 80hr EtG) in a clinical research context.

Methods

A community sample of heavy drinkers (N = 68) completed the 30-day Timeline Follow-Back (TLFB) interview and provided a urine sample for uEtG analysis. Analyses of sensitivity and specificity of the uEtG assay were conducted using the following outcomes: (a) past day drinking, (b) past day binge drinking (defined as ≥4 drinks for women and ≥5 drinks for men), (c) past 3-day drinking, and (d) past 3-day binge drinking.

Results

The majority of participants reported past-3-day drinking (80.9%) and a sizeable minority reported past day drinking (33.8%). While uEtG-based detection of past day drinking and binge drinking was acceptable (sensitivity = 73.91%, and 83.33%; specificity = 80.00% and 66.13%, respectively), detection of any drinking and binge drinking in the past 3 days was poor (sensitivity and specificity of 43.64% and 84.62%, and 39.39% and 62.86%, respectively).

Conclusions

This study contributes to the mixed findings on the validity of EtG tests, which suggest that commercial uEtG tests with conservative detection thresholds are not a reliable alcohol biomarker without corroborating self-report data. Lower detection thresholds are recommended when using uEtG as an alcohol biomarker. Efforts to reach acceptable levels of sensitivity and specificity with commercial assays hold potential to advance the measurement of alcohol intake, overcoming the pitfalls of self-report data.

Repetitive transcranial magnetic stimulation targeting the insular cortex for reduction of heavy drinking in treatment-seeking alcohol-dependent subjects: a randomized controlled trial

Insula responses to drug cues are correlated with cravings, and lesions in this area reduce nicotine seeking. Here, we investigated the potential efficacy of repetitive transcranial magnetic stimulation (rTMS) targeting the insula in alcohol addiction. Treatment-seeking alcohol-dependent patients (Diagnostic and Statistical Manual of Mental Disorder, Fourth Edition; N = 56) participated in this double-blind, sham-controlled, randomized trial. Participants received 10 Hz rTMS or sham using an H8 coil, 5 days a week for 3 weeks. Stimulation targeted insular cortex and overlaying regions bilaterally, while excluding anterior prefrontal areas. Craving and self-reported as well as biomarker-based drinking measures were collected at baseline, during treatment, and through 12 weeks. Resting-state magnetic resonance imaging (rsMRI) data were collected before and after treatment. Task-based MRI was used to probe brain correlates of reward processing, affective responses, and alcohol following completion of treatment. A marked overall decrease in craving and drinking measures was observed during treatment, but did not differ between rTMS or sham stimulation. Both groups equally increased their alcohol use following completion of treatment and through the 12-week follow-up. Analysis using seeds in the insula identified differences in resting-state connectivity between active and sham groups at completion of treatment, potentially indicating an ability of treatment to modify insula function. However, while each task robustly replicated brain responses established in the literature, no effects of rTMS were found. Collectively, this study does not support efficacy of rTMS targeting the insula in alcohol addiction.

Alcohol and Bone Turnover Markers among People Living with HIV and Substance Use Disorder

BACKGROUND

Although unhealthy alcohol use and low bone density are prevalent among people living with HIV (PLWH), it is not clear whether alcohol use is associated with bone turnover markers (BTMs), and if so, at what quantity and frequency. The study objective was to examine the association between alcohol and BTMs in PLWH with substance use disorder.

METHODS

We studied a prospective cohort recruited from 2 HIV clinics who met criteria for DSM-IV substance dependence or reported ever injection drug use. Outcomes were BTM of (i) bone formation (serum procollagen type 1 N-terminal propeptide [P1NP]) and (ii) bone resorption (serum C-telopeptide type 1 collagen [CTx]). Alcohol consumption measures included (i) mean number of drinks/d (Timeline Follow-Back [TLFB]) (primary predictor), (ii) any alcohol use on ≥20 of the past 30 days, and phosphatidylethanol (PEth), a biomarker of recent alcohol consumption. Linear regression analysis examined associations between (i) each alcohol measure and each BTM and (ii) change in alcohol and change in BTM over 12 months.

RESULTS

Among 198 participants, baseline characteristics were as follows: The median age was 50 years; 38% were female; 93% were prescribed antiretroviral medications; 13% had ≥20 drinking days/month; mean drinks/day was 1.93 (SD 3.89); change in mean drinks/day was -0.42 (SD 4.18); mean P1NP was 73.1 ng/ml (SD 34.5); and mean CTx was 0.36 ng/ml (SD 0.34). Higher drinks/day was significantly associated with lower P1NP (slope -1.09 ng/ml; 95% confidence interval [CI] -1.94, -0.23, per each additional drink). On average, those who drank on ≥ 20 days/month had lower P1NP (-15.45 ng/ml; 95% CI: -26.23, -4.67) than those who did not. Similarly, PEth level ≥ 8ng/ml was associated with lower P1NP. An increase in drinks/d was associated with a decrease in P1NP nonsignificantly (-1.14; 95% CI: -2.40, +0.12; p = 0.08, per each additional drink). No significant associations were detected between either alcohol measure and CTx.

CONCLUSIONS

In this sample of PLWH with substance use disorder, greater alcohol consumption was associated with lower serum levels of bone formation markers.

An Optimized Solid-Phase Microextraction and Gas Chromatography–Mass Spectrometry Assay for the Determination of Ethyl Palmitate in Hair

The use of hair as a matrix for the evaluation of chronic ethanol drinking behavior presents the advantage of a longer window of detection and higher specificity when compared to classical biochemical markers. The most recent recommendations the Society of Hair Testing (SOHT) indicate that ethyl palmitate (EtP) hair levels can be used to estimate the ethanol drinking behavior, alternatively to the combined measurement of four main fatty acid ethyl esters. In this study, solid-phase microextraction (SPME) conditions for the extraction of EtP from hair were optimized using response surface analysis, after a Box–Behnken experiment. Analyses were performed by GC-MS. The optimized HS-SPME conditions, using a PDMS-DVB (65 μm) fiber, were pre-adsorption time of 6 min, extraction time of 60 min and incubation temperature of 94°C. The linear range was 0.05 to 3 ng mg−1, with accuracy within 95.15–109.91%. Between-assay and within-assay precision were 8.58–12.53 and 6.12–6.82%, respectively. The extraction yield was 61.3–71.9%. The assay was applied to hair specimens obtained from 46 volunteers, all presenting EtP levels within the linear range of the assay. Using a statistically designed experiment, a sensitive SPME-GC-MS assay for the measurement of EtP in hair was developed and validated, requiring only 20 mg of hair.

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

BACKGROUND

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

METHODS

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

RESULTS

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

CONCLUSIONS

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

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.

Harmful alcohol use among acutely ill hospitalized medical patients in Oslo and Moscow: A cross-sectional study

BACKGROUND

The aim was to estimate the prevalence of harmful alcohol use in relation to socio-demographic characteristics among acutely ill medical patients, and examine identification measures of alcohol use, including the alcohol biomarker phosphatidylethanol 16:0/18:1 (PEth).

METHODS

A cross-sectional study, lasting one year at one hospital in Oslo, Norway and one in Moscow, Russia recruiting acute medically ill patients (≥ 18 years), able to give informed consent. Self-reported data on socio-demographics, mental distress (Symptom Check List-5), alcohol use (Alcohol Use Disorder Identification Test-4 (AUDIT-4) and alcohol consumption past 24 h were collected. PEth and alcohol concentration were measured in whole blood.

RESULTS

Of 5883 participating patients, 19.2% in Moscow and 21.1% in Oslo were harmful alcohol users, measured by AUDIT-4, while the prevalence of PEth-positive patients was lower: 11.4% in Oslo, 14.3% in Moscow. Men in Moscow were more likely to be harmful users by AUDIT-4 and PEth compared to men in Oslo, except of those being ≥ 71 years. Women in Oslo were more likely to be harmful users compared to those in Moscow by AUDIT-4, but not by PEth for those aged < 61 years.

CONCLUSIONS

The prevalence of harmful alcohol use was high at both study sites. The prevalence of harmful alcohol use was lower when assessed by PEth compared to AUDIT-4. Thus, self-reporting was the most sensitive measure in revealing harmful alcohol use among all groups except for women in Moscow. Hence, screening and identification with objective biomarkers and self-reporting might be a method for early intervention.

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.