Comparison of phosphatidylethanol results to self-reported alcohol consumption among young injection drug users

The impact of alcohol and illicit substance use on the pharmacokinetics of first-line TB drugs

BACKGROUND

In South Africa, an estimated 11% of the population have high alcohol use, a major risk factor for TB. Alcohol and other substance use are also associated with poor treatment response, with a potential mechanism being altered TB drug pharmacokinetics.

OBJECTIVES

To investigate the impact of alcohol and illicit substance use on the pharmacokinetics of first-line TB drugs in participants with pulmonary TB.

METHODS

We prospectively enrolled participants ≥15 years old, without HIV, and initiating drug-susceptible TB treatment in Worcester, South Africa. Alcohol use was measured via self-report and blood biomarkers. Other illicit substances were captured through a urine drug test. Plasma samples were drawn 1 month into treatment pre-dose, and 1.5, 3, 5 and 8 h post-dose. Non-linear mixed-effects modelling was used to describe the pharmacokinetics of rifampicin, isoniazid, pyrazinamide and ethambutol. Alcohol and drug use were tested as covariates.

RESULTS

The study included 104 participants, of whom 70% were male, with a median age of 37 years (IQR 27-48). Alcohol use was high, with 42% and 28% of participants having moderate and high alcohol use, respectively. Rifampicin and isoniazid had slightly lower pharmacokinetics compared with previous reports, whereas pyrazinamide and ethambutol were consistent. No significant alcohol use effect was detected, other than 13% higher ethambutol clearance in participants with high alcohol use. Methaqualone use reduced rifampicin bioavailability by 19%.

CONCLUSION

No clinically relevant effect of alcohol use was observed on the pharmacokinetics of first-line TB drugs, suggesting that poor treatment outcome is unlikely due to pharmacokinetic alterations. That methaqualone reduced rifampicin means dose adjustment may be beneficial.

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

BACKGROUND

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

AIMS

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

METHODS

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

RESULTS

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

CONCLUSION

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

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.

Phosphatidylethanol and self-reported alcohol consumption among people living with HIV in Thai Nguyen, Vietnam

BACKGROUND

Phosphatidylethanol (PEth) is a biomarker for recent alcohol consumption that would ideally validate self-reported alcohol consumption behaviors. We assessed the relationship between PEth and several self-reported alcohol consumption metrics among hazardous alcohol users living with HIV in Vietnam.

METHODS

Participants in a three-arm randomized controlled trial assessing two alcohol interventions reported recent alcohol consumption on a 30-day timeline follow-back interview and had a PEth assessment at enrollment, 3 months, and 12 months of the study follow-up. We examined the relationship between self-reported alcohol consumption and quantitative PEth results using Spearman rank correlation and receiver-operating characteristic (ROC) curves to calculate the area under the curve (AUC). We assessed associations between categorical PEth results and self-reported drinking behaviors using prevalence ratios calculated with regression models and generalized estimating equations.

RESULTS

Among 1221 study visits (n = 439 participants; 425 (97%) men), the median PEth result was 71 ng/mL (Interquartile range (IQR): 20, 212), and participants reported a median of 11 (IQR: 4, 24) drinking days and 25 (IQR: 8, 71) standard drinks in the previous 28 days. Quantitative PEth results were moderately correlated with drinking days (ρ = 0.26-0.35) and standard drinks consumed (ρ = 0.23-0.38) in the same period. AUCs ranged from 0.54 (any binge drinking in the past 28 days) to 0.82 (any alcohol consumed in the past 21 days). Positive PEth results (≥50 ng/mL) were 2.24 (95% Confidence Interval [CI]: 1.49, 3.35) times as prevalent among participants who reported drinking in the previous 28 days compared with those who did not.

CONCLUSIONS

Although PEth values and self-reported alcohol use were correlated, the observed associations were modest. Additional research into the dynamics of PEth production and elimination is warranted across diverse populations to better understand how PEth assessments can best be integrated into research and clinical care.

Screening for hazardous alcohol use in the Emergency Department: Comparison of phosphatidylethanol with the Alcohol Use Disorders Identification Test and the Timeline Follow-back

BACKGROUND

Up to 15% of all visits to the Emergency Department (ED) are alcohol related. Identification of problematic alcohol use is important in this setting because it allows for intervention and prevention efforts. This study investigated the correlation between the objective phosphatidylethanol (PEth) marker and the subjective Alcohol Use Disorders Identification Test (AUDIT) and Timeline Followback Questionnaire (TLFB) as screening methods for hazardous alcohol use in the general ED population.

METHODS

This prospective cohort study included 301 ED patients (57% male) who were seen in the ED and required to give a blood sample. The correlation between the values of PEth (PEth 16:0/18:1 and PEth 16:0/18:2) and the scores on the AUDIT and TLFB were analyzed using Spearman's rank correlation coefficient. Differences between risk categories of PEth and AUDIT were also examined.

RESULTS

The Spearman correlation coefficients between PEth 16:0/18:1|PEth 16:0/18:2 values and the AUDIT scores were moderate (PEth 16:0/18:1: 0.67, p < 0.001; PEth 16:0/18:2: 0.67, p < 0.001). Of the patients who scored 'low risk drinking/abstinence' according to the AUDIT questionnaire, respectively 1% and 4% had PEth 16:0/18:1|PEth 16:0/18:2 values indicating excessive alcohol use, and another 10% and 12% had PEth 16:0/18:1|PEth 16:0/18:2 values indicating moderate alcohol consumption. Of the 12 (PEth 16:0/18:1) and 25 (PEth 16:0/18:2) patients with high-risk values, respectively 25% and 40% scored in the lowest risk category on the AUDIT questionnaire. Spearman correlation coefficients between PEth 16:0/18:1|PEth 16:0/18:2 values and TLFB two-week scores were high (PEth 16:0/18:1: 0.74, p < 0.001; PEth 16:0/18:2: 0.82, p < 0.001).

CONCLUSIONS

AUDIT scores were moderately correlated with PEth values in the general ED population. In almost all cases where there was not a good correlation, patients had high PEth values with low AUDIT scores. We conclude that PEth identifies patients with problematic alcohol use who are missed by the AUDIT questionnaire and therefore PEth could be used as an additional screening method for hazardous alcohol use in this population.

Digital Health Screening in People With HIV in Uganda to Increase Alcohol Use Reporting: Qualitative Study on the Development and Testing of the Self-administered Digital Screener for Health

Background

Alcohol consumption is a critical driver of the HIV epidemic worldwide, particularly in sub-Saharan Africa, where unhealthy alcohol use and HIV are prevalent. Brief alcohol interventions are effective in reducing alcohol use; however, they depend on effective screening for unhealthy alcohol use, which is often underreported. Thus, there is a need to develop methods to improve reporting of unhealthy alcohol use as an essential step toward referral to brief alcohol interventions. Self-administered digital health screeners may improve reporting.

Objective

This study aimed to develop and test a digital, easy-to-use self-administered health screener. The health screener was designed to be implemented in a busy, underresourced HIV treatment setting and used by patients with varying levels of literacy.

Methods

We conducted a qualitative study at the Immune Suppression Syndrome (ISS) Clinic of Mbarara Regional Referral Hospital in Uganda to develop and test a digital self-administered health screener. The health screener included a training module and assessed behaviors regarding general health, HIV care, and mental health as well as sensitive topics such as alcohol use and sexual health. We conducted focus group discussions with clinicians and patients with HIV of the Mbarara ISS Clinic who consumed alcohol to obtain input on the need for and content, format, and feasibility of the proposed screener. We iteratively revised a tablet-based screener with a subset of these participants, piloted the revised screener, and conducted individual semistructured in-depth interviews with 20 participants who had taken part in our previous studies on alcohol and HIV, including those who had previously underreported alcohol use and with low literacy.

Results

A total of 45 people (n=5, 11% clinicians and n=40, 89% Mbarara ISS Clinic patients) participated in the study. Of the patient participants, 65% (26/40) were male, 43% (17/40) had low literacy, and all (40/40, 100%) had self-reported alcohol use in previous studies. Clinicians and patients cited benefits such as time savings, easing of staff burden, mitigation of patient-provider tension around sensitive issues, and information communication, but also identified areas of training required, issues of security of the device, and confidentiality concerns. Patients also stated fear of forgetting how to use the tablet, making mistakes, and losing information as barriers to uptake. In pilot tests of the prototype, patients liked the feature of a recorded voice in the local language and found the screener easy to use, although many required additional help and training from the study staff to complete the screener.

Conclusions

We found a self-administered digital health screener to be appealing to patients and clinicians and usable in a busy HIV clinic setting, albeit with concerns about confidentiality and training. Such a screener may be useful in improving reporting of unhealthy alcohol use for referral to interventions.

Correlates of high phosphatidylethanol (PEth) levels and their concordance with self-reported heavy alcohol consumption among men who have sex with men who binge drink alcohol

BACKGROUND

Heavy alcohol use, including binge drinking, is associated with high morbidity and mortality among men who have sex with men (MSM). Self-reported alcohol measures may lead to inaccurate estimates due to recall and social desirability biases. Objective alcohol biomarkers like phosphatidylethanol (PEth) can be used to corroborate self-report and could help to inform treatment approaches and research strategies for alcohol using MSM.

METHODS

From 2015 to 2020, alcohol using MSM ≥18 years were enrolled in a randomized controlled trial evaluating the efficacy of naltrexone in reducing binge drinking. Using this trial's baseline data, we applied multivariable logistic regression to identify the correlates of high PEth levels (i.e., ≥87 ng/ml) and concordance between PEth levels and self-reported heavy drinking.

RESULTS

Of 118 MSM, 64% had PEth levels ≥87 ng/ml and 72% had PEth levels that were concordant with self-reported heavy alcohol use. Factors significantly associated in separate models with elevated PEth levels were income ≥$60,000 (adjusted odds ratio [aOR] = 4.09; 95% CI = 1.13 to 14.82), being employed (aOR = 4.04; 95% CI = 1.45 to 11.32), episodic cannabis use (aOR = 4.63; 95% CI = 1.27 to 16.92), and any alcohol/substance use prior to or during anal intercourse (aOR = 2.52; 95% CI = 1.08 to 5.90). Living with HIV was associated with significantly lower odds of elevated PEth levels (aOR = 0.23; 95% CI = 0.09 to 0.61). Factors associated with significantly higher concordance between PEth levels and self-reported heavy alcohol use included at least weekly use of poppers (aOR = 6.41; 95% CI = 1.27 to 32.28) and polysubstance use (aOR = 2.53; 95% CI = 1.02 to 6.27). Living with HIV was associated with lower odds of concordance (aOR = 0.36; 95% CI = 0.14 to 0.97).

CONCLUSIONS

PEth may enhance the detection of heavy drinking among MSM, including the identification of subpopulations that may benefit from targeted alcohol reduction interventions. However, PEth values for MSM living with HIV showed modest concordance with self-reported alcohol use and may need to be supplemented with additional biomarkers or evaluated against a different cutoff.

Factors associated with phosphatidylethanol (PEth) sensitivity for detecting unhealthy alcohol use: An individual patient data meta-analysis

BACKGROUND

Objective measurement of alcohol consumption is important for clinical care and research. Adjusting for self-reported alcohol use, we conducted an individual participant data (IPD) meta-analysis to examine factors associated with the sensitivity of phosphatidylethanol (PEth), an alcohol metabolite, among persons self-reporting unhealthy alcohol consumption.

METHODS

We identified 21 eligible studies and obtained 4073 observations from 3085 participants with Alcohol Use Disorders Identification Test-Consumption (AUDIT-C) positive scores (≥3 for women and ≥4 for men) and PEth measurements. We conducted 1-step IPD meta-analysis using mixed effects models with random intercepts for study site. We examined the associations between demographic (sex, race/ethnicity, and age) and biologic (body mass index-BMI, hemoglobin, HIV status, liver fibrosis, and venous versus finger-prick blood collection) variables with PEth sensitivity (PEth≥8 ng/ml), adjusting for the level of self-reported alcohol use using the AUDIT-C score.

RESULTS

One third (31%) of participants were women, 32% were African, 28% African American, 28% White, and 12% other race/ethnicity. PEth sensitivity (i.e., ≥8 ng/ml) was 81.8%. After adjusting for AUDIT-C, we found no associations of sex, age, race/ethnicity, or method of blood collection with PEth sensitivity. In models that additionally included biologic variables, those with higher hemoglobin and indeterminate and advanced liver fibrosis had significantly higher odds of PEth sensitivity; those with higher BMI and those living with HIV had significantly lower odds of PEth sensitivity. African Americans and Africans had higher odds of PEth sensitivity than whites in models that included biologic variables.

CONCLUSIONS

Among people reporting unhealthy alcohol use, several biological factors (hemoglobin, BMI, liver fibrosis, and HIV status) were associated with PEth sensitivity. Race/ethnicity was associated with PEth sensitivity in some models but age, sex, and method of blood collection were not. Clinicians should be aware of these factors, and researchers should consider adjusting analyses for these characteristics where possible.

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.

Racial Discrimination, Protective Parenting, and Binge Drinking Among Emerging Adult Black Men

PURPOSE

Rural Black men experience escalating rates of binge drinking during emerging adulthood. We hypothesized that exposure to racial discrimination would predict growth in their binge-drinking trajectories and that protective parenting, including emotional and instrumental support and high expectations for success, would attenuate the influence of racial discrimination on growth in binge drinking.

METHODS

Hypotheses were tested with 3 waves of data from 505 men (ages 20.3, 21.9, and 23.1) participating in the African American Men's Project. Conditional and multigroup latent growth curve models (LGCMs) were implemented using Mplus.

RESULTS

LGCM indicated that binge-drinking frequency increased linearly across time; exposure to racial discrimination at baseline predicted growth in binge drinking (β = 0.19, p < 0.01). Multigroup comparison procedures indicated significant moderation by protective parenting. When protective parenting was high, racial discrimination had no significant influence on rates of young men's binge drinking (β = 0.01, p = 0.51). In contrast, when protective parenting was low, the influence of discrimination was heightened (β = 0.21, p < 0.01).

CONCLUSIONS

Racial discrimination is a pernicious stressor that contributes to increases in binge drinking among young Black men. When parents engaged in emotionally and instrumentally supportive parenting, however, racial discrimination had little influence on binge-drinking trajectories during emerging adulthood. Study findings underscore the importance of the emerging adult transition as a period of vulnerability and suggest directions for targeting alcohol preventive interventions.

IMPLICATIONS AND CONTRIBUTION

After high school, young Black men are exposed to racial discrimination that can increase rates of binge drinking. When young men's parents were emotionally and instrumentally supportive toward them, however, racial discrimination did not predict increases in binge drinking.

HCV incidence is associated with injecting partner age and HCV serostatus mixing in young adults who inject drugs in San Francisco

BACKGROUND

HCV incidence is increasing in the US, notably among younger people who inject drugs (PWID). In a cohort of young adult (age<30 years) PWID in San Francisco we examined whether 'injecting partner mixing' factors, i.e. age of partner and knowledge of their HCV serostatus, were associated with HCV transmission.

METHODS

In 448 susceptible PWID studied prospectively. All participants were asked to report characteristics and behaviors they engaged in with up to 3 injecting partners defined as "people whom you injected the most with" in the past month". These partnerships did not specify that drugs or injecting equipment was shared. HCV incidence was estimated by age of up to 3 injecting partners, categorized as: (i) all <30; (ii) mixed-age (<&≥30); and (iii) all ≥30 years and perceived knowledge of the HCV status of participants' injecting partners' HCV status. Interaction was evaluated between partnership age categories and perceived HCV status of partners.

RESULTS

Between 2006-2018, overall HCV incidence (/100 person years observation [pyo]) was 19.4 (95% CI: 16.4, 22.9). Incidence was highest in those with mixed-age partnerships: 28.5 (95% CI: 21.8, 37.1) and those whose partners were all <30 (23.9; 95% CI: 18.8, 30.4), and lowest if partners were ≥30 (7.5; 95% CI: 4.8, 11.8). In a multivariable analyses adjusting for age, sex (of index), injection frequency, and injection partnership 'monogamy', we found evidence for an interaction: the highest HCV incidence was seen in PWID whose partners were all <30 and who knew at least one of their partners was HCV-positive (58.9, 95% CI: 43.3, 80.0; p<0.01).

CONCLUSIONS

Younger injectors are more likely to acquire HCV from their similarly-aged peers, than older injecting partners. Protective seroadaptive behavior may contribute to reduce incidence. These findings can inform new HCV prevention approaches for young PWID needed to curb the HCV epidemic.

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.

Overlapping epidemics of alcohol and illicit drug use among HCV-infected persons who inject drugs

BACKGROUND

Alcohol use in people who inject drugs (PWID) with hepatitis C virus (HCV) infection accelerates liver disease progression. This paper describes the prevalence and associated correlates of alcohol use among HCV antibody positive PWID.

METHODS

In a large cohort of HCV antibody positive PWID (N = 1623) followed from 2005 to 2013, we characterized alcohol use using the AUDIT-C. We used multivariable logistic regression with generalized estimated equations to examine socio-demographic, clinical, and substance use correlates of alcohol use.

RESULTS

At their initial visit, 41% reported no, 21% reported moderate, and 38% reported heavy alcohol use. The odds of moderate and heavy alcohol use increased with greater intensity of substance use represented by a composite summary variable which ranged from 0 to 3 substances (street-acquired prescription drugs, non-injection cocaine/heroin, and injection drugs) used. Compared to those who used no drugs, those who used 3 substances had 3.71 odds (95% CI: 3.07-4.48) of moderate alcohol use and 3.65 odds (95% CI: 3.20-4.16) of heavy alcohol use.

CONCLUSIONS

The prevalence of moderate/heavy alcohol use is high among HCV antibody positive PWID and occurs frequently in combination with other drug use. This may contribute to progressive liver fibrosis thus limiting the gains achieved from HCV cure. Public health interventions need to address the overlapping epidemics of HCV, alcohol use, and other substance use in this population.

Biomarker-Measured Unhealthy Alcohol Use in Relation to CD4 Count Among Individuals Starting ART in Sub-Saharan Africa

Individuals are initiating antiretroviral therapy (ART) at earlier HIV disease stages. Unhealthy alcohol use is a known barrier to successful HIV treatment outcomes, yet it is unclear whether the problem varies by disease stage. We measured alcohol use with an objective biomarker (phosphatidylethanol [PEth]), comparing individuals (n = 401) with early (CD4 > 350 cells/mL, WHO Stage 1) versus late (CD4 < 200 cells/mL) ART initiation in HIV care in Uganda and South Africa (SA). We examined the association between CD4 count and biomarker results using multivariable regression modeling, and compared PEth results to self-report to assess underreporting. Overall, 32.2% (n = 129) had unhealthy alcohol use (PEth ≥ 50 ng/ml). Early ART initiation was significantly associated with unhealthy alcohol use in Uganda (AOR 2.65; 95% CI: 1.05–6.72), but not SA (AOR 1.00; 95% CI: 0.46–2.17). In Uganda, 23.2% underreported unhealthy alcohol use versus 11.6% in SA (χ² = 9.30; p < 0.01). Addressing unhealthy alcohol use is important as patients initiate ART earlier, yet challenging due to underreporting.

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

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

Alcohol and Mortality: Combining Self-Reported (AUDIT-C) and Biomarker Detected (PEth) Alcohol Measures Among HIV Infected and Uninfected

BACKGROUND

Unhealthy alcohol use may be particularly detrimental among individuals living with HIV and/or hepatitis C virus (HCV), and is often under-reported. Direct biomarkers of alcohol exposure may facilitate improved detection of alcohol use.

METHODS

We evaluated the association of alcohol exposure determined by both self-report [Alcohol Use Disorders Identification Test-Consumption (AUDIT-C)] and a direct biomarker [phosphatidylethanol (PEth)], with mortality among HIV-infected and HIV-uninfected in the Veterans Aging Cohort Study-Biomarker Cohort. We considered PEth <8 ng/mL to represent no alcohol use. Alcohol exposure by AUDIT-C scores [0, 1-3/1-2 (men/women), 4-7/3-7 (men/women), 8-12] and PEth (<8, ≥8) was combined into categories to model the relationship of alcohol with mortality. Participants were followed from blood collection date for 5 years or until death within 5 years.

RESULTS

The sample included 2344 (1513 HIV+; 831 uninfected) individuals, 95% men. During a median follow-up of 5 years, 13% died. Overall, 36% were infected with HCV (40% HIV+/HCV+, 27% HIV-/HCV+). Overall, 43% (1015/2344) had AUDIT-C = 0 (abstinence). Of these, 15% (149/1015) had PEth ≥8 suggesting recent alcohol exposure. Among those with AUDIT-C = 0, HCV+ individuals were more likely to have PEth ≥8. After controlling for age, sex, race, HIV, HCV, and HIV viral suppression, those with AUDIT-C = 0 but PEth ≥8 had the highest risk of mortality (adjusted hazard ratio 2.15, 95% confidence interval: 1.40 to 3.29).

CONCLUSIONS

PEth in addition to self-report may improve detection of alcohol use in clinical settings, particularly among those at increased risk of harm from alcohol use. Individuals infected with HCV were more likely to under-report alcohol use.

Impact of alcohol consumption on tuberculosis treatment outcomes: a prospective longitudinal cohort study protocol

BACKGROUND

An estimated 10% of tuberculosis (TB) deaths are attributable to problematic alcohol use globally, however the causal pathways through which problem alcohol use has an impact on TB treatment outcome is not clear. This study aims to improve understanding of these mechanisms. Specifically, we aim to 1) assess whether poor TB treatment outcomes, measured as delayed time-to-culture conversion, are associated with problem alcohol use after controlling for non-adherence to TB pharmacotherapy; and 2) to determine whether pharmacokinetic (PK) changes in those with problem alcohol use are associated with delayed culture conversion, higher treatment failure/relapse rates or with increased toxicity.

METHODS

Our longitudinal, repeated measures, prospective cohort study aims to examine the associations between problem alcohol use and TB treatment outcomes and to evaluate the effect of alcohol on the PK and pharmacodynamics (PD) of TB drugs. We will recruit 438 microbiologically confirmed, pulmonary TB patients with evidence of rifampicin susceptibility in Worcester, South Africa with 200 HIV uninfected patients co-enrolled in the PK aim. Participants are followed for the six months of TB treatment and an additional 12 months thereafter, with sputum collected weekly for the first 12 weeks of treatment, alcohol consumption measures repeated monthly in concert with an alcohol biomarker (phosphatidylethanol) measurement at baseline, and in person directly observed therapy (DOT) using real-time mobile phone-based adherence monitoring. The primary outcome is based on time to culture conversion with the second objective to compare PK of first line TB therapy in those with and without problem alcohol use.

DISCUSSION

Globally, an urgent need exists to identify modifiable drivers of poor TB treatment outcomes. There is a critical need for more effective TB treatment strategies for patients with a history of problem alcohol use. However, it is not known whether poor treatment outcomes in alcohol using patients are solely attributable to noncompliance. This study will attempt to answer this question and provide guidance for future TB intervention trials.

TRIAL REGISTRATION

Clinicaltrials.gov Registration Number: NCT02840877 . Registered on 19 July 2016.

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

BACKGROUND

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

METHODS

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

RESULTS

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

CONCLUSIONS

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

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

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

Assessing phosphatidylethanol (PEth) levels reflecting different drinking habits in comparison to the alcohol use disorders identification test - C (AUDIT-C)

In addition to monitoring problematic or harmful alcohol consumption, drinking experiments indicated the potential of phosphatidylethanols (PEth) in abstinence monitoring. To date, no profound evaluation of thresholds for the differentiation of abstinence from moderate drinking and for detection of excessive consumption based on PEth homologues exists. Investigations with a large group of healthy volunteers (n=300) were performed to establish PEth reference values reflecting different drinking habits. Blood samples were analyzed for PEth 16:0/18:1 and 16:0/18:2 by online-SPE-LC-MS/MS method. Results were compared to AUDIT-C questionnaires, to the amounts of alcohol consumed during the two-weeks prior to blood sampling, and were statistically evaluated. PEth concentrations were significantly correlated with self-reported alcohol consumption (r>0.69) and with AUDIT-C scores (r>0.65). 4.0% of 300 volunteers reported abstinence (AUDIT-C score: 0), no PEth was detectable in their blood. PEth 16:0/18:1 concentrations below the limit of detection of 10.0ng/mL match with abstinence and light drinking habits (≤10g pure alcohol/day). However, some volunteers classified as "excessive alcohol consumers" had negative PEth results. In the group of volunteers classified as "moderate drinkers" (AUDIT-C score: 1-3 (women) and 1-4 (men)), 95% of the test persons had PEth 16:0/18:1 ranging from not detected to 112ng/mL, and PEth 16:0/18:2 ranging from not detected to 67.0ng/mL. Combination of self-reported alcohol consumption and AUDIT-C score showed that negative PEth results match with abstinence or light drinking. Moderate alcohol consumption resulted in PEth 16:0/18:1 from 0 to 112ng/mL and for PEth 16:0/18:2 ranged from 0 to 67.0ng/mL. Higher PEth concentrations indicated excessive alcohol consumption.

Phosphatidylethanol (PEth) as a Biomarker of Alcohol Consumption in HIV-Infected Young Russian Women: Comparison to Self-Report Assessments of Alcohol Use

Alcohol use is particularly deleterious for HIV-infected individuals and thus accurate assessment of alcohol consumption is crucial in this population. Phosphatidylethanol (PEth) provides an objective assessment of drinking and can be compared to self-reported alcohol assessments to detect underreporting. The purpose of this study was to identify underreporting and its potential predictors in an HIV-infected sample of young Russian women. The current study examined the concordance between a quantitative measure of PEth and self-reported recent alcohol consumption in a prospective sample of HIV-infected young women (N = 204) receiving medical care in Saint Petersburg, Russia. At baseline, 53% of participants who denied drinking in the prior 30 days tested positive for PEth (i.e., underreporters), although this rate decreased significantly at a three-month follow-up assessment. Further exploration did not identify consistent predictors of underreporting status. Quantitative PEth levels showed, at best, modest overlap to self-reported alcohol consumption among those reporting alcohol use (e.g., Spearman's r = 0.27 between PEth and total drinks past-30 days at baseline). Objective measures of alcohol consumption demonstrate modest overlap with self-report measures of use in HIV-infected young Russian women. Incorporating objective and quantifiable biological markers are essential for valid assessments of alcohol use.

Binge Drinking Episodes in Young Adults: How Should We Measure Them in a Research Setting?

OBJECTIVE

Worldwide, consequences of binge drinking are a major health and policy concern. This article reviews contemporary binge drinking definitions as well as different questionnaires and biomarkers that have been used in research settings to examine binge drinking behavior among young adults.

METHOD

A review of electronic databases was conducted for binge drinking definitions, questionnaires, and biomarkers for the measurement of binge drinking in young adults (18-30 years).

RESULTS

Binge drinking is often defined as four or more drinks for females and five or more drinks for males on an occasion or in one sitting within a designated time frame (2 weeks vs. past 30 days). Several tools and questionnaires are available to identify young adult repeated binge drinkers. Biomarkers have been used to corroborate self-reported alcohol consumption, of which direct biomarkers such as phosphatidylethanol may be useful in confirming recent heavy drinking.

CONCLUSIONS

It is important to measure binge drinking along a continuum and to use questions that allow for assessment of intensity, frequency, duration, and daily versus weekend consumption patterns. Open-ended questions that allow for intensity (number of drinks) and frequency can be used to determine dose-response relationships with respect to specific outcome measures. Direct alcohol biomarkers reflecting alcohol consumption over a period of several days are useful in conjunction with questionnaire data for identifying young adult binge drinkers.

Sparse canonical correlation analysis between an alcohol biomarker and self-reported alcohol consumption

In investigating the correlation between an alcohol biomarker and self-report, we developed a method to estimate the canonical correlation between two high-dimensional random vectors with a small sample size. In reviewing the relevant literature, we found that our method is somewhat similar to an existing method, but that the existing method has been criticized as lacking theoretical grounding in comparison with an alternative approach. We provide theoretical and empirical grounding for our method, and we customize it for our application to produce a novel method, which selects linear combinations that are step functions with a sparse number of steps.

The effects of alcohol on spontaneous clearance of acute hepatitis C virus infection in females versus males

BACKGROUND

Approximately one quarter of persons exposed to hepatitis C virus (HCV) will spontaneously clear infection. We undertook this study to investigate the impact of alcohol on likelihood of HCV spontaneous viral clearance stratified by sex groups.

METHODS

Pooled data from an international collaboration of prospective observational studies of incident HIV and HCV infection in high-risk cohorts (the InC3 Study) was restricted to 411 persons (or 560.7 person-years of observation) with documented acute HCV infection and data regarding alcohol use. The predictor of interest was self-reported alcohol use at or after estimated date of incident HCV infection and the outcome was HCV spontaneous clearance. Sex stratified Cox proportional hazards models were used to evaluate the association between alcohol and spontaneous clearance, adjusting for age, race/ethnicity, and IFNL4 genotype.

RESULTS

The median age was 28.5 years, 30.4% were women, 87.2% were white, and 71.8% reported alcohol use at or after incident infection. There were 89 (21.6%) cases of spontaneous clearance observed, 39 (31.2%) among women and 50 (17.5%) in men (p<0.01). Overall, spontaneous clearance occurred less frequently among participants who drank alcohol compared to those who did not drink (18.9% v. 28.5%, p=0.03). After adjustment for other covariates, alcohol was significantly and independently associated with lower relative hazards for spontaneous clearance of HCV in women (AHR=0.35; 95% CI: 0.19-0.66; p=0.001) but not in men (AHR=0.63; 95% CI: 0.36-1.09; p=0.10).

CONCLUSION

Results indicate that abstaining from drinking alcohol may increase the likelihood of spontaneous clearance among women.

Hazardous Alcohol Use Associated with Increased Sexual Risk Behaviors Among People Who Inject Drugs

BACKGROUND

Alcohol is associated with a multitude of severe health consequences. While risk behaviors related to illicit drug use are commonly studied among people who inject drugs (PWID), the role of alcohol use has received substantially less attention in this population. We explored whether drug and sexual risk behaviors as well as experiences of violence were associated with hazardous alcohol use in a cohort of PWID.

METHODS

Analyses were conducted using observational data from a prospective cohort of community-recruited HIV-negative PWID in Vancouver, Canada. We used the U.S. National Institute on Alcohol Abuse and Alcoholism definition of hazardous alcohol use (i.e., >14 drinks/wk or >4 drinks on 1 occasion for men, and >7 drinks/wk or >3 drinks on 1 occasion for women). We used multivariable generalized estimating equations (GEE) to identify the factors associated with hazardous alcohol use.

RESULTS

Between 2006 and 2012, 1,114 HIV-negative individuals were recruited, and 186 (16.7%) reported hazardous alcohol use in the previous 6 months at baseline. In multivariable GEE analyses, having multiple sex partners (adjusted odds ratio [AOR] = 1.25), history of sexually transmitted infection (AOR = 1.50), experiencing violence (AOR = 1.36), and incarceration (AOR = 1.29) were each independently associated with hazardous alcohol use. Caucasian ethnicity (AOR = 0.56), ≥ daily heroin injection (AOR = 0.81), and engagement in addiction treatment (AOR = 0.84) were negatively associated with hazardous alcohol use (all p < 0.05).

CONCLUSIONS

A considerable proportion of PWID reported hazardous alcohol use, which was independently associated with reporting sexual, but not drug-related, HIV risk behaviors and experiencing recent violence. Findings suggest a need to integrate regular screening and evidence-based alcohol interventions into treatment efforts for PWID.

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

BACKGROUND

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

METHODS

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

RESULTS

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

CONCLUSIONS

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

High prevalence of unhealthy alcohol use and comparison of self-reported alcohol consumption to phosphatidylethanol among women engaged in sex work and their male clients in Cambodia

BACKGROUND

In Cambodia, most of the female sex workers (FSW) work in venues where unhealthy alcohol use is ubiquitous and potentially contributing to the HIV epidemic. However, no accurate data exists. We compare self-reported unhealthy alcohol consumption to a biomarker of alcohol intake in Cambodian FSW and male clients, and determine factors associated with unhealthy alcohol use.

METHODS

A cross-sectional study was conducted among FSW (n=100) and male clients (n=100) in entertainment and sex work venues in Cambodia. Self-reported unhealthy alcohol use (AUDIT-C) was compared to phosphatidylethanol (PEth) positive (≥50ng/ml), a biomarker of alcohol intake. Sociodemographics data was collected. Correlates of self-reported unhealthy alcohol use and PEth positive were determined.

RESULTS

The prevalence of PEth positive in FSW was 60.0%. Self-reported unhealthy alcohol consumption was reported by 85.0% of the women. Almost all women (95.0%) testing PEth positive also reported unhealthy alcohol use. Prevalence of unhealthy alcohol consumption (self-report and PEth positive) was higher in FSW working in entertainment establishments compared to other sex work venues (p<0.01). Among male clients, 47.0% reported unhealthy alcohol consumption and 42.0% had a PEth positive. However, only 57.1% of male clients with PEth positive reported unhealthy alcohol use.

CONCLUSIONS

Unhealthy alcohol consumption is prevalent in Cambodian sex work settings. Self-reported unhealthy alcohol use is well reported by FSW, but less by male clients. These findings highlight the urgency of using accurate measures of unhealthy alcohol consumption and integrating this health issue into HIV prevention interventions.

Comparison of self-reported alcohol use with the alcohol biomarker phosphatidylethanol among young people in northern Tanzania

BACKGROUND

The one-month Time Line Follow Back calendar (TLFB) and the Alcohol Use Disorders Identification Test (AUDIT) are used to collect self-reported alcohol intake data. We compared these instruments with the alcohol biomarker phosphatidylethanol (PEth) among young-people in northern Tanzania.

METHODS

AUDIT and TLFB were applied in a cross-sectional study of 202 young people (18-24 years), who reported using alcohol during the past year (103 male casual labourers; 99 college students). We assayed whole blood for PEth 16:0/18:1, using liquid chromatography-tandem mass spectrometry.

RESULTS

For both self-report methods, alcohol consumption was high, particularly among men (e.g. a median of 54 drinks per month in labourers), and about half of male students (48%) reported hazardous or harmful levels of drinking (AUDIT ≥8). Almost half (49%) of participants were PEth-positive (median concentration 0.03μmol/L). There were significant positive correlations between reported total alcohol intake and PEth concentration in males (Spearman's correlation rs=0.65 in college students and rs=0.57 in casual labourers; p<0.001). Self-reported use in the past month was a sensitive marker of having a positive PEth result (≥0.01μmol/L) with 89% of those with a PEth positive result reporting alcohol use, and this was similar in all groups. The proportion of those with AUDIT scores ≥8 and AUDIT-C scores ≥6 among those with a high cut-off positive PEth result (≥0.30μmol/L) ranged between 94 and 100%.

CONCLUSION

TLFB and AUDIT are sensitive measures to detect heavy alcohol use among young-people in northern Tanzania. They can be used to identify young people who may benefit from alcohol-focused interventions.

Comparison of Traditional and Novel Self-Report Measures to an Alcohol Biomarker for Quantifying Alcohol Consumption Among HIV-Infected Adults in Sub-Saharan Africa

BACKGROUND

In Sub-Saharan Africa (SSA), HIV-infected patients may underreport alcohol consumption. We compared self-reports of drinking to phosphatidylethanol (PEth), an alcohol biomarker. In particular, we assessed beverage-type-adjusted fractional graduated frequency (FGF) and quantity frequency (QF) measures of grams of alcohol, novel nonvolume measures, and the Alcohol Use Disorders Identification Test-Consumption (AUDIT-C).

METHODS

We analyzed cohort entry data from the Biomarker Research of Ethanol Among Those with HIV cohort study (2011 to 2013). Participants were HIV-infected past-year drinkers, newly enrolled into care. Self-report measures included FGF and QF grams of alcohol, the AUDIT-C, number of drinking days, and novel adaptations of FGF and QF methods to expenditures on alcohol, time spent drinking, and symptoms of intoxication. PEth levels were measured from dried blood spots. We calculated Spearman's rank correlation coefficients of self-reports with PEth and bias-corrected bootstrap 95% confidence intervals (CIs) for pairwise differences between coefficients.

RESULTS

A total of 209 subjects (57% men) were included. Median age was 30; interquartile range (IQR) 25 to 38. FGF grams of alcohol over the past 90 days (median 592, IQR 43 to 2,137) were higher than QF grams (375, IQR 33 to 1,776), p < 0.001. However, both measures were moderately correlated with PEth: ρ = 0.58, 95% CI 0.47 to 0.66 for FGF grams and 0.54, 95% CI 0.43 to 0.63 for QF grams (95% CI for difference -0.017 to 0.099, not statistically significant). AUDIT-C, time drinking, and a scale of symptoms of intoxication were similarly correlated with PEth (ρ = 0.35 to 0.57).

CONCLUSIONS

HIV-infected drinkers in SSA likely underreport both any alcohol consumption and amounts consumed, suggesting the need to use more objective measures like biomarkers when measuring drinking in this population. Although the FGF method may more accurately estimate drinking than QF methods, the AUDIT-C and other nonvolume measures may provide simpler alternatives.

Biomolecules and Biomarkers Used in Diagnosis of Alcohol Drinking and in Monitoring Therapeutic Interventions

BACKGROUND

The quantitative, measurable detection of drinking is important for the successful treatment of alcohol misuse in transplantation of patients with alcohol disorders, people living with human immunodeficiency virus that need to adhere to medication, and special occupational hazard offenders, many of whom continually deny drinking. Their initial misconduct usually leads to medical problems associated with drinking, impulsive social behavior, and drunk driving. The accurate identification of alcohol consumption via biochemical tests contributes significantly to the monitoring of drinking behavior.

METHODS

A systematic review of the current methods used to measure biomarkers of alcohol consumption was conducted using PubMed and Google Scholar databases (2010-2015). The names of the tests have been identified. The methods and publications that correlate between the social instruments and the biochemical tests were further investigated. There is a clear need for assays standardization to ensure the use of these biochemical tests as routine biomarkers.

FINDINGS

Alcohol ingestion can be measured using a breath test. Because alcohol is rapidly eliminated from the circulation, the time for detection by this analysis is in the range of hours. Alcohol consumption can alternatively be detected by direct measurement of ethanol concentration in blood or urine. Several markers have been proposed to extend the interval and sensitivities of detection, including ethyl glucuronide and ethyl sulfate in urine, phosphatidylethanol in blood, and ethyl glucuronide and fatty acid ethyl esters in hair, among others. Moreover, there is a need to correlate the indirect biomarker carbohydrate deficient transferrin, which reflects longer lasting consumption of higher amounts of alcohol, with serum γ-glutamyl transpeptidase, another long term indirect biomarker that is routinely used and standardized in laboratory medicine.

Phosphatidylethanol Compared with Other Blood Tests as a Biomarker of Moderate Alcohol Consumption in Healthy Volunteers: A Prospective Randomized Study

AIM

It is generally agreed that traditional alcohol biomarkers lack in sensitivity to detect hazardous alcohol consumption. The present study was undertaken to evaluate the ability of phosphatidylethanol (PEth) and traditional alcohol markers to detect moderate alcohol consumption and to distinguish between moderate alcohol consumption and abstinence.

METHODS

Forty-four subjects, 32 females and 12 males, were included in the study. They were randomized to alcohol abstention or to alcohol consumption. Female participants consumed 150 ml of red wine (equivalent to 16 g of alcohol) per 24 h and the male participants double the amount. The study lasted for 3 months. Blood samples were drawn at the start and at the end of the study period. Blood samples were analysed for PEth, carbohydrate-deficient transferrin (CDT), mean corpuscular volume (MCV), γ-glutamyltransferase (GGT), aspartate aminotransferase (AST) and alanine aminotransferase (ALT).

RESULTS

ROC curves for the various biochemical markers were plotted in order to assess their ability to discriminate between abstention and moderate daily consumption of alcohol. PEth and CDT were the only markers with AUROCs significantly higher than 0.5, and PEth was detected in all participants randomized to alcohol consumption.

CONCLUSION

PEth was the only marker that could detect moderate intake and the present results also indicate that PEth probably can distinguish moderate alcohol consumption from abstinence.