Analytical and diagnostic aspects of carbohydrate deficient transferrin (CDT): A critical review over years 2007-2017

Brief history of the alcohol biomarkers CDT, EtG, EtS, 5-HTOL, and PEth

This article traces the historical development of various biomarkers of acute and/or chronic alcohol consumption. Much of the research in this domain of clinical and laboratory medicine arose from clinics and laboratories in Sweden, as exemplified by carbohydrate deficient transferrin (CDT) and phosphatidylethanol (PEth). Extensive studies of other alcohol biomarkers, such as ethyl glucuronide (EtG), ethyl sulfate (EtS), and 5-hydroxytryptophol (5-HTOL), also derive from Sweden. The most obvious test of recent drinking is identification of ethanol in a sample of the person's blood, breath, or urine. However, because of continuous metabolism in the liver, ethanol is eliminated from the blood at a rate of 0.15 g/L/h (range 0.1-0.3 g/L/h), so obtaining positive results is not always possible. The widow of detection is increased by analysis of ethanol's non-oxidative metabolites (EtG and EtS), which are more slowly eliminated from the bloodstream. Likewise, an elevated ratio of serotonin metabolites in urine (5-HTOL/5-HIAA) can help to disclose recent drinking after ethanol is no longer measurable in body fluids. A highly specific biomarker of hazardous drinking is CDT, a serum glycoprotein (transferrin), with a deficiency in its N-linked glycosylation. Another widely acclaimed biomarker is PEth, an abnormal phospholipid synthesized in cell membranes when people drink excessively, having a long elimination half-life (median ~6 days) during abstinence. Research on the subject of alcohol biomarkers has increased appreciably and is now an important area of drug testing and analysis.

Defining trimester-specific reference intervals for carbohydrate deficient transferrin in pregnant women

OBJECTIVES

Extensive consumption of alcohol during pregnancy can lead to severe complications for the unborn child. Carbohydrate-deficient transferrin (CDT) levels in serum have become a common biomarker for excessive alcohol intake. However, during pregnancy CDT levels can rise to levels above commonly used cut-off values, for reasons unrelated to alcohol intake. The aim of this study is to investigate the changes in CDT values during pregnancy and to determine accurate, trimester dependent reference intervals.

METHODS

439 serum samples of 147 healthy pregnant women were obtained for trimester 1, 2, 3, and post-partum and were analysed by high-performance liquid chromatography (HPLC) and an N-Latex immunonephelometric assay. New trimester-specific reference intervals were established.

RESULTS

This study demonstrates there is a trimester-dependent increase of %CDT, as up to 39.4% of the population exceeded the previously established upper reference limit of 1.7%. In our study the estimated upper reference limit for %DST/%CDT were 1.55%, 1.96%, 2.05% and 1.35% for trimester 1, 2, 3 and post-partum for the HPLC-method and 2.02%, 2.19%, 2.19% and 1.96% for the N-Latex immunoassay.

CONCLUSIONS

We demonstrate that CDT levels rise during pregnancy. The magnitude of the increase is method-dependent and needs to be taken into account. We have established method- and trimester-specific reference intervals to prevent false-positive results in alcohol abuse screening tests during pregnancy.

Exploring the diverse applications of Carbohydrate macromolecules in food, pharmaceutical, and environmental technologies

Carbohydrates are a class of macromolecules that has significant potential across several domains, including the organisation of genetic material, provision of structural support, and facilitation of defence mechanisms against invasion. Their molecular diversity enables a vast array of essential functions, such as energy storage, immunological signalling, and the modification of food texture and consistency. Due to their rheological characteristics, solubility, sweetness, hygroscopicity, ability to prevent crystallization, flavour encapsulation, and coating capabilities, carbohydrates are useful in food products. Carbohydrates hold potential for the future of therapeutic development due to their important role in sustained drug release, drug targeting, immune antigens, and adjuvants. Bio-based packaging provides an emerging phase of materials that offer biodegradability and biocompatibility, serving as a substitute for traditional non-biodegradable polymers used as coatings on paper. Blending polyhydroxyalkanoates (PHA) with carbohydrate biopolymers, such as starch, cellulose, polylactic acid, etc., reduces the undesirable qualities of PHA, such as crystallinity and brittleness, and enhances the PHA's properties in addition to minimizing manufacturing costs. Carbohydrate-based biopolymeric nanoparticles are a viable and cost-effective way to boost agricultural yields, which is crucial for the increasing global population. The use of biopolymeric nanoparticles derived from carbohydrates is a potential and economically viable approach to enhance the quality and quantity of agricultural harvests, which is of utmost importance given the developing global population. The carbohydrate biopolymers may play in plant protection against pathogenic fungi by inhibiting spore germination and mycelial growth, may act as effective elicitors inducing the plant immune system to cope with pathogens. Furthermore, they can be utilised as carriers in controlled-release formulations of agrochemicals or other active ingredients, offering an alternative approach to conventional fungicides. It is expected that this review provides an extensive summary of the application of carbohydrates in the realms of food, pharmaceuticals, and environment.

Carbohydrate-Deficient Transferrin (CDT) as a Biomarker of Alcohol Abuse: A Retrospective Study of the Italian Drinking Trend among Drivers from 2016 to 2022

Alcohol abuse is still one of the leading causes of death worldwide. Early diagnosis of alcohol abuse enables preventive intervention on the effects and risks associated with its consumption. Carbohydrate-deficient transferrin (CDT) is one of the most reliable biomarkers of chronic alcohol misuse. We retrospectively studied a population of 12,624 subjects who had their driving license suspended for driving under the influence of alcohol or drugs from 2016 to 2022. The analytical determination of CDT was performed following a certified high-performance liquid chromatography (HPLC) method. Data were split by year, age and gender. The majority of subjects with positive %CDT were male, although the trend of positivity was similar between males and females. A steady increase in both the number of tests performed and the number of positives was observed over the years. Patients aged 41-50 years had the highest prevalence, followed by 51-60, 31-40 and 18-30 years. CDT continues to be a steady marker for diagnosis of alcohol abuse in the majority of cases. Data emerging from our study are in line with the increasing national trends on traffic accidents, injuries and deaths related to alcohol and drug DUI (driving under the influence), requiring the implementation of preventive measures to limit this ever-growing phenomenon.

Multivariate classification based on large-scale brain networks during early abstinence predicted lapse among male detoxified alcohol-dependent patients

Identifying biomarkers to predict lapse of alcohol-dependence (AD) is essential for treatment and prevention strategies, but remains remarkably challenging. With an aim to identify neuroimaging features for predicting AD lapse, 66 male AD patients during early-abstinence (baseline) after hospitalized detoxification underwent resting-state functional magnetic resonance imaging and were then followed-up for 6 months. The relevance-vector-machine (RVM) analysis on baseline large-scale brain networks yielded an elegant model for differentiating relapsing patients (n = 38) from abstainers, with the area under the curve of 0.912 and the accuracy by leave-one-out cross-validation of 0.833. This model captured key information about neuro-connectome biomarkers for predicting AD lapse.

Epigenetic and Proteomic Biomarkers of Elevated Alcohol Use Predict Epigenetic Aging and Cell-Type variation Better Than Self-Report

Excessive alcohol consumption (EAC) has a generally accepted effect on morbidity and mortality, outcomes thought to be reflected in measures of epigenetic aging (EA). As the association of self-reported EAC with EA has not been consistent with these expectations, underscoring the need for readily employable non-self-report tools for accurately assessing and monitoring the contribution of EAC to accelerated EA, newly developed alcohol consumption DNA methylation indices, such as the Alcohol T Score (ATS) and Methyl DetectR (MDR), may be helpful. To test that hypothesis, we used these new indices along with the carbohydrate deficient transferrin (CDT), concurrent as well as past self-reports of EAC, and well-established measures of cigarette smoking to examine the relationship of EAC to both accelerated EA and immune cell counts in a cohort of 437 young Black American adults. We found that MDR, CDT, and ATS were intercorrelated, even after controlling for gender and cotinine effects. Correlations between EA and self-reported EAC were low or non-significant, replicating prior research, whereas correlations with non-self-report indices were significant and more substantial. Comparing non-self-report indices showed that the ATS predicted more than four times as much variance in EA, CDT4 cells and B-cells as for both the MDR and CDT, and better predicted indices of accelerated EA. We conclude that each of the non-self-report indices have differing predictive capacities with respect to key alcohol-related health outcomes, and that the ATS may be particularly useful for clinicians seeking to understand and prevent accelerated EA. The results also underscore the likelihood of substantial underestimates of problematic use when self-report is used and a reduction in correlations with EA and variance in cell-types.

Digital methylation assessments of alcohol and cigarette consumption account for common variance in accelerated epigenetic ageing

Smoking and Heavy Alcohol Consumption (HAC) are established risk factors for myriad complex disorders of ageing. Yet many prior studies of Epigenetic Ageing (EA) have shown only modest effects of smoking and drinking on accelerated ageing. One potential reason for this conundrum might be the reliance of some prior EA studies on self-reported substance use, which may be unreliable in many samples. To test whether novel, non-self-reported indices would show a stronger association of smoking and HAC to EA, we used methylation sensitive digital PCR (MSdPCR) and data from 437 African American subjects from Wave 7 of the Family and Community Health Study Offspring Cohort to examine the effects of subjective and objective measures of smoking and HAC on 7 indices of EA. Because of limited overall correlations between the various EA indices, we examined patterns of association separately for each index. Consistent with expectations, MSdPCR assessments of smoking and HAC, but not self-reported alcohol consumption, were strongly correlated with accelerated EA. MSdPCR assessments of smoking and HAC accounted for 57% of GrimAge acceleration and the shared variance in GrimAge and DunedinPOAM accelerated EA. We conclude that MSdPCR assessments of smoking and HAC are valuable tools for understanding EA, represent directly targetable conditions for the prevention of premature ageing, and substantially improve upon self-reported assessment of smoking and HAC.

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

BACKGROUND AND AIMS

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

DESIGN

Observational study.

SETTING

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

PARTICIPANTS

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

MEASUREMENTS

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

FINDINGS

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

CONCLUSIONS

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

Data-driven study on resting-state functional magnetic resonance imaging during early abstinence of alcohol dependence in male patients and its predictive value for relapse

BACKGROUND

Alcohol dependence is a mental disorder with a high relapse rate. However, specific neuroimaging biomarkers have not been determined for alcohol dependence and its relapse. We conducted data-driven research to investigate resting-state functional magnetic resonance imaging (rs-fMRI) during early abstinence from alcohol dependence and its potential ability to predict relapse.

METHODS

Participants included 68 alcohol-dependent patients and 68 healthy controls (HCs). The regional homogeneity (ReHo) and fractional amplitude of low-frequency fluctuations (fALFF) were compared between the alcohol dependence group and the HCs and between the relapse group and the nonrelapse group. The brain regions that presented significantly different ReHo and/or fALFF between the alcohol-dependent patients and HCs and/or between the relapsed and nonrelapsed patients were selected as the seeds to calculate the functional connectivities (FCs).

RESULTS

During a 6-month follow-up period, 52.24% of alcohol-dependent patients relapsed. A regression model for differentiating alcohol-dependent patients and HCs showed that reductions in ReHo in the left postcentral region, fALFF in the right fusiform region, and FC in the right fusiform region to the right middle cingulum were independently associated with alcohol dependence, with an area under the receiver operating characteristic curve (AUC) of 0.841. The baseline FC of the left precentral to the left cerebellum of the relapse group was significantly lower than that of the nonrelapse group. The AUC of this FC to predict relapse was 0.774.

CONCLUSIONS

Our findings contribute to advancing research on the neurobiological etiology and predictive biomarkers for relapse associated with alcohol dependence.

Accuracy of carbohydrate-deficient transferrin as a biomarker of chronic alcohol abuse during treatment for alcoholism

AIM

Clinical evaluations are generally used to verify the effectiveness of detoxification treatments for alcohol dependence, but new objective biomarkers are essential for accurate diagnosis. We aim to assess the accuracy of carbohydrate-deficient transferrin (%CDT) in a cohort of Japanese patients admitted to a psychiatric hospital specializing in alcohol dependence. In addition, we investigated the kinetics of %CDT during alcohol moderation or cessation.

METHODS

The study cohort consisted of 126 alcohol-dependent patients. The levels of serum %CDT were assessed by the N Latex CDT direct immunonephelometric assay.

RESULTS

Alcohol consumption was significantly correlated with %CDT. The only independent predictive factor of alcohol consumption was %CDT, with glutamyltranspeptidase (GGT) and albumin-bilirubin score proving insufficient. The cut-off value of %CDT was 1.9% with high sensitivity and specificity in detecting alcohol abstinence beyond 30 days (68.6% sensitivity, 91.8% specificity) and excessive alcohol drinking (77.9% sensitivity, 77.1% specificity). The %CDT levels were significantly decreased at 30 days of abstinence when compared with baseline. Notably, %CDT values were significantly changed even in the light alcohol drinking cohort (p = 0.0009), whereas GGT levels were not significantly changed.

CONCLUSIONS

Our results indicate that %CDT is an accurate and specific biomarker of alcohol consumption and is useful in detecting alcohol abstinence even in a low alcohol intake patient cohort. These results suggest that %CDT could be a useful objective biomarker of chronic alcohol abuse during clinical treatment for alcoholism.

A novel high-throughput liquid chromatography assay for Carbohydrate-Deficient transferrin (CDT) based on flow-modulated isocratic elution and terbium-induced fluorescence

Transferrin is a glycoprotein containing two bi- or tri-antennary carbohydrate chains ending with sialic acid. Its glycosylation is reduced in chronic alcohol abuse and in inborn glycosylation pathologies, where the carbohydrate-deficient fraction of the protein (CDT) increases significantly. The current methods require a gradient chromatographic separation and time-consuming sample preparation. In comparison, the proposed approach uses a novel flow-modulated liquid chromatography technique (fmLC) and a highly selective and sensitive fluorescence derivatization reaction with terbium ion. A fmLC-FLD method using isocratic anion exchange separation was optimized and validated to resolve disialo-transferrin and trisialo-transferrin from other transferrin glycoforms. Detection took place by recording fluorescence at 550 nm wavelength (excitation at 298 nm). The chromatographic separation needed 5 min, allowing seriate injection every 7.5 min. The method was validated according to the current guidelines of analytical chemistry showing adequate accuracy and precision for the quantitative determination of CDT. The proposed method proved also to be suitable to analyse haemolyzed sera which, because of interference by haemoglobin, fail the standard HPLC-Vis analysis. The method was tested in parallel with HPLC-Vis on 131 sera showing an excellent correlation of results proved by a correlation coefficient of 0.995 (Pearson's r). The proposed approach proved much simpler than the current methods and cheaper in terms of instrumental costs offering a ground-breaking analytical tool that could likely make available the characterization of CDT outside specialized laboratories, such as in occupational medicine centres, doctor's offices, small laboratories, alcohol rehabilitation centres, and in developing countries.

Prevalence and Factors Associated with Fear of COVID-19 Among Homeless Individuals During the COVID-19 Pandemic: Evidence from the Hamburg Survey of Homeless Individuals

PURPOSE

To clarify the prevalence and determinants of fear of COVID-19 among homeless individuals during the COVID-19 pandemic.

PATIENTS AND METHODS

Data were taken from the Hamburg survey of homeless individuals (n=150) covering homeless adults in Hamburg, Germany. Multiple linear regressions were used. Beyond sociodemographic and lifestyle-related independent variables, COVID-19-related factors were also used as independent variables.

RESULTS

In sum, 56.2% of homeless individuals reported no fear of COVID-19, 23.8% reported a little fear of COVID-19, 9.2% reported some fear of COVID-19 and 10.8% reported severe fear of COVID-19. Regressions showed that an increased fear of COVID-19 was significantly associated with younger age (β=-.01, p<0.05), absence of chronic alcohol consume (β=-.55, p<0.01), an increased perceived own risk of getting infected with the coronavirus one day (β=0.42, p<0.001) and a higher agreement that a diagnosis of the coronavirus would ruin his/her life (β=0.13, p<0.01).

CONCLUSION

Given the poor hygienic conditions and their increased vulnerability, data surprisingly suggest a quite low fear of COVID-19 among homeless individuals. Efforts may be beneficial which contribute to thinking rationally about COVID-19 among homeless people, since low levels of fear of COVID-19 may contribute to careless behavior and can lead to super-spreading events.

Alcohol-Related Liver Disease: Basic Mechanisms and Clinical Perspectives

Alcohol-related liver disease (ALD) refers to the liver damage occurring due to excessive alcohol consumption and involves a broad spectrum of diseases that includes liver steatosis, steatohepatitis, hepatitis, cirrhosis, and hepatocellular carcinoma (HCC). The progression of ALD is mainly associated with the amount and duration of alcohol usage; however, it is also influenced by genetic, epigenetic, and environmental factors. The definite diagnosis of ALD is based on a liver biopsy, although several non-invasive diagnostic tools and serum biomarkers have emerging roles in the early detection of ALD. While alcohol abstinence and nutritional support remain the cornerstone of ALD treatment, growing evidence has revealed that the therapeutic agents that target oxidative stress or gut-liver axis, inflammatory response inhibition, and liver regeneration enhancement also play a role in ALD management. Furthermore, microRNAs modulation and mesenchymal stem cell-based therapy have emerging potential as ALD therapeutic options. This review summarizes the updated understanding of the pathophysiology, diagnosis, and novel therapeutic approaches for ALD.

Determinants of health care use among homeless individuals: evidence from the Hamburg survey of homeless individuals

BACKGROUND

To identify the determinants of health care use among homeless individuals.

METHODS

Data were taken from the Hamburg survey of homeless individuals (n = 100 individuals in the here used model, mean age 44.8 years, SD 12.5) focusing on homeless individuals in Hamburg, Germany. The number of physician visits in the past 3 months and hospitalization in the preceding 12 months were used as outcome measures. Drawing on the Andersen model of health care use as a conceptual framework, predisposing characteristics, enabling resources and need factors as well as psychosocial variables were included as correlates.

RESULTS

Negative binomial regressions showed that increased physician visits were associated with being female (IRR: 4.02 [95% CI: 1.60-10.11]), absence of chronic alcohol consume (IRR: 0.26 [95% CI: 0.12-0.57]) and lower health-related quality of life (IRR: 0.97 [95% CI: 0.96-0.98]). Furthermore, logistic regressions showed that the likelihood of hospitalization was positively associated with lower age (OR: 0.93 [95% CI: 0.89-0.98]), having health insurance (OR: 8.11 [2.11-30.80]) and lower health-related quality of life (OR: 0.97 [95% CI: 0.94-0.99]).

CONCLUSIONS

Our study showed that predisposing characteristics (both age and sex), enabling resources (i.e., health insurance) and need factors in terms of health-related quality of life are main drivers of health care use among homeless individuals. This knowledge may assist in managing health care use.

Loneliness among Homeless Individuals during the First Wave of the COVID-19 Pandemic

The feeling of loneliness is a major public health concern associated with multiple somatic and psychiatric illnesses. Studies have shown increasing incidence of loneliness in the general population during the first wave of the COVID-19 pandemic. Homeless individuals are a particularly vulnerable group; however, little is known about loneliness among homeless individuals. We therefore aimed to examine the prevalence of loneliness among homeless individuals during the pandemic. Furthermore, we estimated the association between loneliness and sociodemographic and lifestyle factors, as well as the self-perceived risk of contracting COVID-19. Data from the Hamburg survey of homeless individuals were used, including 151 homeless individuals that were recruited in spring of 2020. Loneliness was measured by the 3- item version of the UCLA-3 Loneliness Scale. To summarize, 48.5% of the participants experienced loneliness. Multiple linear regressions showed increased loneliness to be associated with male gender (β = 1.07, p = 0.01), being single (β = 1.33, p = 0.00), originating from Germany (β = 1.48, p = 0.00), high frequency of sharing a sleeping space with more than three people (β = 0.42, p = 0.02) and a higher self-perceived risk of contracting COVID-19 (β = 0.41, p = 0.02). On the contrary, there was no association of loneliness with age, educational level, chronic alcohol consumption or frequently sharing a sleeping space. In conclusion, the magnitude of loneliness among homeless individuals during the pandemic was highlighted. Description of factors determining loneliness may help to identify homeless individuals at risk.

Determinants of health-related quality of life among homeless individuals during the COVID-19 pandemic

OBJECTIVE

To clarify which variables are associated with the health-related quality of life (HRQoL) among homeless individuals during the COVID-19 pandemic.

STUDY DESIGN

Cross-sectional research.

METHODS

Data were taken from the Hamburg survey of homeless individuals (n = 151). HRQoL was assessed using the EQ-5D tool. More precisely, the EQ-5D-5L questionnaire was used to quantify problems in five health dimensions (i.e. mobility, self-care, usually activities, pain/discomfort, anxiety/depression), and its visual analog scale (EQ-VAS) was used to record the according self-rated health status. Explanatory variables include sex, age, education, marital status, country of origin, health insurance, and chronic alcohol consumption.

RESULTS

With regard to HRQoL, most frequently, problems were reported as pain/discomfort (47.3%), followed by anxiety/depression (32.4%), mobility (29.7%), usual activities (20.7%) and self-care (4.6%). The mean EQ-VAS score was 75.34 (SD 22.23; range 1-100), and the mean EQ-5D-5L index was 0.84 (SD 0.23; range 0.32-1). Regressions showed increasing problems in mobility and self-care with higher age, whereas EQ-VAS was positively associated with younger age. Furthermore, EQ-5D-5L index was positively associated with younger age and higher education. Summarized, among this cohort, a higher age is associated with a lower HRQoL.

CONCLUSION

Remarkably high EQ-VAS values and rather few problems in the five dimensions investigated here were reported among the homeless individuals during the COVID-19 pandemic particularly compared with the general population. Moreover, study findings particularly stress the link between higher age and lower HRQoL among homeless individuals. This knowledge is important to address homeless individuals at risk of poor HRQoL. Longitudinal studies are required to confirm the given findings.

Electrochemical sensor for the assessment of carbohydrate deficient transferrin: Application to diagnosis of congenital disorders of glycosilation

Carbohydrate deficient transferrin (CDT) is used as biomarker of different health problems as, for example, congenital disorders of glycosylation (CDG). We propose a screen-printed-based electrochemical sensor for the determination of carbohydrate deficient transferrin using an Os (VI) tag-based electrochemistry. When transferrin is labeled with Os (VI) complex, it generates two voltammetric signals: one from carbohydrates (electrochemical signal of osmium (VI) complex at -0.9 V/Ag) and one from the amino acids present in glycoprotein (intrinsic electrochemical signal of glycoprotein at +0.8 V/Ag). The relationship between the two analytical signals (carbohydrate signal/protein signal) is an indicator of the degree of glycosylation (electrochemical index of glycosylation), which has shown an excellent correlation (r = 0.990) with the official parameter %CDT obtained by CE-UV. The suitability of this approach was demonstrated by analyzing serum samples from CDG patients.

Evaluation of the diagnostic utility of carbohydrate-deficient transferrin in chronic alcoholism: Results from Southwest China

Although recent gathered evidence indicates that obtaining the diagnostic value of serum carbohydrate-deficient transferrin might be more useful for identifying alcohol abuse than other widely available biochemical tests; however, its precise value as an indicator of chronic alcoholism is unclear. The main objective is to investigate the diagnostic significance of carbohydrate-deficient transferrin in chronic alcoholism in the Chinese population.In this study, we enrolled (1) 52 physically healthy subjects, (2) 20 patients with nonalcoholic liver disease, and (3) 70 alcoholics. Patients with liver injuries and a history of liver surgery were excluded. Serum gamma-glutamyltransferase, aspartate aminotransferase, alanine aminotransferase, and mean corpuscular volume were determined by standard biochemical assays, and serum carbohydrate-deficient transferrin was estimated in each group using capillary electrophoresis. Subsequently, the diagnostic value of carbohydrate-deficient transferrin (CDT) in chronic alcoholism was determined based on differences between each indicator among the three groups.The CDT level in the alcoholic group was significantly higher than that of the non-alcoholic liver disease and healthy control groups (P < .05). The area under the curve for alcoholism diagnosis was the highest for CDT, at 0.922, whereas those for gamma-glutamyltransferase, aspartate aminotransferase, alanine aminotransferase, and mean corpuscular volume were 0.860, 0.744, 0.615, and 0.754, respectively. When the cutoff value of CDT was set at 1.25%, the sensitivity and specificity were 85.5% and 89.6%, respectively. However, the correlation between CDT and daily alcohol consumption was weak (r = 0.175; P = .16).Compared with the other parameters evaluated, CDT was a better indicator of alcoholism. It should, therefore, be actively promoted in clinical practice. However, the correlation between CDT and daily alcohol consumption needs further evaluation.

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.

Relationship of Phosphatidylethanol Biomarker to Self-Reported Alcohol Drinking Patterns in Older and Middle-Age Adults

BACKGROUND

Risky alcohol consumption is on the rise among older adults. Biomarkers such as phosphatidylethanol (PEth) have been used to evaluate the correspondence between an objective, laboratory-based biomarker and self-report of alcohol consumption. This study examined the relationship between PEth, self-report of alcohol consumption, and health indices in a sample of community-dwelling older to middle-age adults (aged 35 to 89) with healthy and risky levels of alcohol consumption.

METHODS

Self-reports of alcohol consumption were collected using the Alcohol Use Disorders Identification Test (AUDIT) and Form 30. In addition, indices of health along with a blood sample to determine PEth values were collected (N = 183).

RESULTS

PEth was correlated with age, AUDIT-C, AUDIT total, alcohol consumption, mood, and liver function measures but not with medical comorbidity or body mass index (J Gerontol B Psychol Sci Soc Sci 73, 2018, 633). Alcohol consumption over the past 30 days measured with Form 30 was the strongest predictor of PEth levels for both middle-age and older adults, with age a small contributing predictor. General alcohol consumption patterns for amount of alcohol consumed over a 30-day period revealed middle-age adults consumed larger amounts of alcohol compared with older adults, but older adults consumed alcohol on more days than middle-age adults. Middle-age participants evidenced higher PEth levels than older adults at comparable drinking rates.

CONCLUSIONS

Overall, findings suggest a strong relationship between alcohol consumption and PEth levels with age a small but contributing factor to predicting PEth levels.

Mass spectrometry in clinical glycomics: The path from biomarker identification to clinical implementation

Over the past decades, the genome and proteome have been widely explored for biomarker discovery and personalized medicine. However, there is still a large need for improved diagnostics and stratification strategies for a wide range of diseases. Post-translational modification of proteins by glycosylation affects protein structure and function, and glycosylation has been implicated in many prevalent human diseases. Numerous proteins for which the plasma levels are nowadays evaluated in clinical practice are glycoproteins. While the glycosylation of these proteins often changes with disease, their glycosylation status is largely ignored in the clinical setting. Hence, the implementation of glycomic markers in the clinic is still in its infancy. This is for a large part caused by the high complexity of protein glycosylation itself and of the analytical techniques required for their robust quantification. Mass spectrometry-based workflows are particularly suitable for the quantification of glycans and glycoproteins, but still require advances for their transformation from a biomedical research setting to a clinical laboratory. In this review, we describe why and how glycomics is expected to find its role in clinical tests and the status of current mass spectrometry-based methods for clinical glycomics.

A Comparison of the Predictive Power of DNA Methylation with Carbohydrate Deficient Transferrin for Heavy Alcohol Consumption

Currently, the most commonly used biomarker of alcohol consumption patterns is carbohydrate-deficient transferrin (CDT). However, the CDT has limited sensitivity and requires the use of blood. Recently, we have shown that digital DNA methylation techniques can both sensitively and specifically detect heavy alcohol consumption (HAC) using DNA from blood or saliva. In order to better understand the relative performance characteristics of these two tests, we compared an Alcohol T-Score (ATS) derived from our prior study and serum CDT levels in 313 (182 controls and 131 HAC cases) subjects discordant for HAC. Overall, the Receiver Operating Characteristic (ROC) area under the curve (AUC) analyses showed that DNA methylation predicted HAC status better than CDT with AUCs of 0.96 and 0.87, respectively (p < 0.0001). The performance of the CDT was affected by gender while the ATS was not, while both were affected by age. We conclude that DNA methylation is a promising method for quantifying HAC and that further studies to better refine its strengths and limitations are in order.

Evaluation of carbohydrate-deficient transferrin measurements on the V8 capillary electrophoresis system and comparison with the IFCC approved HPLC reference method and N-Latex immunonephelometric assay

OBJECTIVES

Carbohydrate-deficient transferrin (CDT) measurements are commonly used for the identification and follow-up of individuals suspected of chronic alcohol abuse. This study describes the analytical characteristics of the CDT assay on the Helena Biosciences V8 electrophoresis analyzer and compares its diagnostic performance to the International Federation of Clinical Chemistry and Laboratory Medicine approved high performance liquid chromatography (HPLC) method and the N-Latex CDT immunonephelometric assay.

METHODS

The analytical performance of the V8 assay, including the linearity and the imprecision, was studied at two separate locations. Method comparison analysis was performed by studying the correlation, bias and agreement between the V8, HPLC and the N-Latex assays in 231 patient samples.

RESULTS

The total imprecision ranged between 5.1 and 24.3% and was ≤13.1% for samples with concentrations above the clinical cut-off value (≥1.62%). The method comparisons revealed excellent correlations with r²≥0.97 for all comparisons. Measurements on the V8 showed a bias of -0.83 (-22.24%) and -0.40 (-12.26%) with the HPLC and N-Latex assays, respectively. The assays showed excellent agreements (Kappa scores ≥ 0.8) in classifying subjects with elevated CDT values. Receiver operating characteristic (ROC)-curve analysis, using the HPLC classification as reference, revealed areas under the ROC-curves of 0.981 (95% CI, 0.97-0.99) and 0.996 (0.99-1.00) for the N-Latex and V8 assays, respectively.

CONCLUSIONS

CDT measurements on the V8 assay are highly correlated with both the HPLC and the N-Latex assay and show excellent agreement in classifying subjects with elevated CDT values. Overall, the V8 CDT analysis is a robust, reliable and effective method to measure CDT concentrations in serum samples.

CDT reference values for monitoring chronic alcohol abuse in pregnancy

INTRODUCTION AND AIM

Carbohydrate Deficient Transferrin (CDT) is one of the most used biomarkers for monitoring alcohol use in pregnancy. However, its effective application in this context is hampered by the demonstrated physiological progressive increase during pregnancy (even in abstinent women) of CDT values, which in the third trimester can reach values close or exceeding the cut-offs usually adopted in clinical and forensic diagnostics. The present work was aimed at the re-assessment of CDT reference values in pregnancy.

MATERIALS AND METHODS

The CDT analysis was performed by a validated HPLC-UV Vis method on 284 serum samples of women with a physiological pregnancy and on 370 sera of non-pregnant woman from the general population (control group). All the samples were tested also for GGT for excluding alcohol abuse. The statistical analysis was performed using the MedCalc® Statistical Software.

RESULTS

The re-definition of the specific reference concentrations was carried out according to the Horn and Pesce Robust Method. The resulting CDT upper reference values were 1.45%, 2.01% and 2.05% in the first, second, and third trimester, respectively.

CONCLUSIONS

In order to prevent the development of maternal and fetal prenatal alcohol exposure complications, the use of alcohol biomarkers, including CDT, has been proposed. However, this biomarker, in the monitoring of alcohol use in pregnancy, has so far been applied adopting the same cut-off used for general population without taking into consideration the progressive physiological increase of its value throughout the pregnancy. In the present study, a specific re-assessment of the CDT reference concentrations of each trimester is reported.

Alcohol consumption and employment: a cross-sectional study of office workers and unemployed people

Background

Alcohol is a psychoactive substance with toxic and addictive properties. Biomarkers like GGT, AST, ALT and MCV are influenced by excessive ethanol consumption. Alcohol consumption represents a health risk and it has been linked to unemployment. The aim of this study how working status predict alcohol consumption through a cross sectional study comparing alcohol-related biomarkers levels in office workers and unemployed people.

Methods

This study includes 157 office workers and 157 unemployed people, who were recruited from January to December 2018. A propensity score matching procedure was applied to obtain two homogenous groups in terms of age and gender. A non-parametric analysis was performed on serum biomarkers that are generally altered by alcohol consumption. Logistic regression models were designed to evaluate how working status predict abnormal biomarker levels related with alcohol consumption.

Results

No differences in median biomarker values were found between groups. Logistic regression analysis showed that office work is a negative predictor of pathological biomarker levels. Office workers had a significant relation with the levels of GGT (OR 0.48; 95% CI [0.28–0.84]), AST (OR 0.42; 95% CI [0.22–0.78]), ALT (OR 0.39; 95% CI [0.23–0.66]), and MCV (OR 0.37; 95% CI [0.19–0.70]).

Conclusion

Office workers had lower absolute frequencies of pathological values of alcohol consumption biomarkers, after matching for age and gender compared with unemployed people. In addition, a significant negative association between office work is a negative predictor of biomarker levels of alcohol consumption. These results showed that work is an important determinant of health and that can represent a benefit for workers in terms of reducing the risk of consuming alcohol.

Diagnosis of acute intoxications in critically ill patients: focus on biomarkers - part 2: markers for specific intoxications

In medical intensive care units, acute intoxications contribute to a large proportion of all patients. Epidemiology and a basic overview on this topic were presented in part one. The purpose of this second part regarding toxicological biomarkers in the ICU setting focuses on specific poisons and toxins. Following the introduction of anion and osmol gap in part one, it's relevance in toxic alcohols and other biomarkers for these poisonings are presented within this publication. Furthermore, the role of markers in the blood, urine and cerebrospinal fluid for several intoxications is evaluated. Specific details are presented, amongst others, for cardiovascular drug poisoning, paracetamol (acetaminophen), ethanol, pesticides, ricin and yew tree intoxications. Detailed biomarkers and therapeutic decision tools are shown for carbon monoxide (CO) and cyanide (CN^-) poisoning. Also, biomarkers in environmental toxicological situations such as mushroom poisoning and scorpion stings are presented.

Prevalence of risk-drinking in critically ill patients, screened with carbohydrate-deficient transferrin and AUDIT-C score: A retrospective study

Background Studies demonstrate that up to one-third of intensive care unit (ICU) admissions are directly or indirectly related to alcohol. Screening for alcohol use is not routine. This study examined the prevalence of elevated %CDT (carbohydrate-deficient transferrin) and above risk-level AUDIT-C (Alcohol Use Disorders Identification Test, Consumption) in patients admitted to ICU. Methods We conducted a retrospective analysis of clinical and laboratory data from a single ICU where %CDT and AUDIT-C were included in routine assessment. After excluding readmissions, 2532 adult patients from a 21-month period were included. Admission values of %CDT were available for 2049 patients, and AUDIT-C was available for 1617 patients. The association of %CDT and AUDIT-C with short- and long-term outcome was studied by using univariate and multivariate logistic regression analysis. Results %CDT was above the reference value in 23.7% (486/2048) of patients with available %CDT. Of patients with available AUDIT-C, 33% (544/1617) had a risk-level AUDIT-C score. Patients with a risk-level AUDIT-C score were significantly younger than those with a lower score (51 vs 64 years, P < .0001). Increased %CDT was associated with higher severity of illness. AUDIT-C was associated independently with increased risk of long-term mortality in multivariate analysis (P = .007). Conclusion One in three of ICU patients are risk-level alcohol users as measured with AUDIT-C score, and one in four are analysed with %CDT. The prevalence varies according to the method used and any method alone may be insufficient to detect risk-level consumption reliably. Editorial Comment Alcohol overconsumption is associated with need for ICU admission and with less favorable outcomes. Diagnosis of alcohol overconsumption though is problematic due to low sensitivity in screening. In a pilot study, a biomarker and a screening tool are compared. The finding is that multiple tools are needed to achieve an adequate sensitivity for detection.

A proof-of-concept analysis of carbohydrate-deficient transferrin by imaged capillary isoelectric focusing and in-capillary immunodetection

Carbohydrate-deficient transferrin (CDT) is a reliable biomarker for chronic alcohol abuse. We developed a method for CDT analysis by capillary isoelectric focusing, followed by immunodetection directly in the capillary, in an automated fashion and on a single platform (Peggy Sue™; ProteinSimple, CA, USA). Transferrin glycoforms in serum samples, including disialo-transferrin, were separated and their apparent isoelectric points and relative percentages were determined. The relative CDT values (percent of total transferrin) matched expected values for both healthy and alcoholic samples. Because the method leveraged the sensitivity of an immunoassay, CDT was measured when serum samples were diluted up to 1200-fold, reducing the volume of serum required. Finally, the process is fully automated, with up to 96 samples analyzed per batch.

Carbohydrate deficient transferrin (CDT) predicts heavy drinking in adolescents with alcohol dependence

A biomarker that could indicate problematic drinking in adolescents and/or reflect changes in heavy drinking would be a valuable addition to prevention, treatment, and research efforts. Carbohydrate deficient transferrin (CDT) is a valid biomarker of heavy drinking in adults; however, it is not well examined in adolescents. Adolescents with alcohol dependence (AD) (n = 21; 9 females) and non-dependent controls (ND) (n = 6; 3 females), ages 14-20, were interviewed to determine drinks per drinking day, peak number of drinks, and percent days heavy drinking (≥4 standard drinks/day). Blood samples from participants were assayed for percent of transferrin that was carbohydrate deficient (%CDT). Analyses compared groups on drinking and %CDT, examined the relationship between %CDT and indices of drinking, and provided preliminary estimates of the test validity of %CDT for heavy drinking in adolescents. Among adolescents with AD, %CDT was significantly and strongly correlated (r = .54) with percent heavy drinking days, and this relationship was consistent for both males and females. AD adolescents did not differ from ND on mean %CDT levels, despite significantly greater alcohol use. Indicators of test validity showed that %CDT had low sensitivity (33%) but adequate specificity (83%) for heavy drinking. Results provide proof of concept that %CDT is a potentially valuable tool to use in alcohol treatment and research in adolescents. Even if %CDT does not discriminate between adolescents with and without alcohol dependence, it could be an effective monitoring tool to indicate changes over time in binge drinking. Improved %CDT measurement methods might enhance its utility.

Changes in the Human Metabolome Associated With Alcohol Use: A Review

AIMS

The metabolome refers to the functional status of the cell, organ or the whole body. Metabolomic methods measure the metabolome (metabolite profile) which can be used to examine disease progression and treatment responses. Here, our aim was to review metabolomics studies examining effects of alcohol use in humans.

METHODS

We performed a literature search using PubMed and Web of Science for reports on changes in the human metabolite profile associated with alcohol use; we found a total of 23 articles published before end of 2018.

RESULTS

Most studies had investigated plasma, serum or urine samples; only four studies had examined other sample types (liver, faeces and broncho-alveolar lavage fluid). Levels of 51 metabolites were altered in two or more of the reviewed studies. Alcohol use was associated with changes in the levels of lipids and amino acids. In general, levels of fatty acids, phosphatidylcholine diacyls and steroid metabolites tended to increase, whereas those of phosphatidylcholine acyl-alkyls and hydroxysphingomyelins declined. Common alterations in circulatory levels of amino acids included decreased levels of glutamine, and increased levels of tyrosine and alanine.

CONCLUSIONS

More studies, especially with a longitudinal study design, or using more varied sample materials (e.g. organs or saliva), are needed to clarify alcohol-induced diseases and alterations at a target organ level. Hopefully, this will lead to the discovery of new treatments, improved recognition of individuals at high risk and identification of those subjects who would benefit most from certain treatments.

Elimination Characteristics of the Alcohol Biomarker Phosphatidylethanol (PEth) in Blood during Alcohol Detoxification

Aims

The study documented elimination characteristics of three phosphatidylethanol (PEth) homologs in serially collected blood samples from 47 heavy drinkers during ~2 weeks of alcohol detoxification at hospital.

Methods

Venous whole blood and urine samples were collected every 1–2 days during treatment. Concentrations of PEth, and of urinary ethyl glucuronide (EtG) and ethyl sulfate (EtS) to detect relapse drinking, were measured using liquid chromatography-tandem mass spectrometry.

Results

When included in the study, negative or decreasing breath ethanol concentrations demonstrated that the patients were in the elimination phase. The EtG and EtS measurements further confirmed alcohol abstinence during the study, with three exceptions. On admission, all patients tested positive for PEth, the total concentration ranging 0.82–11.7 (mean 6.35, median 5.88) μmol/l. PEth 16:0/18:1, 16:0/18:2 and 16:0/20:4 accounted for on average ~42%, ~26% and ~9%, respectively, of total PEth in these samples. There were good correlations between total PEth and individual homologs (P < 0.0001). There was no significant difference in PEth values between male and female subjects. During abstinence, the elimination half-life values ranged 3.5–9.8 days for total PEth, 3.7–10.4 days for PEth 16:0/18:1, 2.7–8.5 days for PEth 16:0/18:2 and 2.3–8.4 days for PEth 16:0/20:4.

Conclusions

The results demonstrated a very high sensitivity (100%) of PEth as alcohol biomarker for recent heavy drinking, but considerable differences in the elimination rates between individuals and between different PEth forms. This indicates that it is possible to make only approximate estimates of the quantity and recency of alcohol intake based on a single PEth value.

A real-world study on clinical predictors of relapse after hospitalized detoxification in a Chinese cohort with alcohol dependence

Background

The relapse rate of alcohol dependence (AD) after detoxification is high, but few studies have investigated the clinical predictors of relapse after hospitalized detoxification in real-world clinical practice, especially among Chinese patients.

Methods

This longitudinal cohort study followed up 122 AD patients who were discharged from January 1, 2016 to January 30, 2018 from their most recent hospitalization for detoxification. These patients were interviewed by telephone from May 20, 2017, to June 30, 2018, at least 6 months after discharge. During the interview, the relapse were assessed by using a revised Chinese version of the Alcohol Use Disorder Identification Test. Candidate predictors, such as therapeutic modalities during hospitalization and at discharge, medical history data related to alcohol use, and demographic information, were obtained from the medical records in the hospital information system.

Results

During the 6-24 months (with a median of 9 months) follow-up period, the relapse rate was 53.3%. Individuals with a college education level and those who had not been treated with the brief comprehensive cognitive-motivational-behavioural intervention (CCMBI) were more likely than their counterparts to relapse after hospitalized detoxification, and their adjusted HRs (95% CIs) were 1.85 (1.09, 3.16) and 2.00 (1.16, 3.46), respectively. The CCMBI use predicted a reduction in the relapse rate by approximately one-fifth.

Conclusion

Undergoing the CCMBI during detoxification hospitalization and having less than a college-level education could predict a reduced risk of AD relapse. These findings provide useful information both for further clinical research and for real-world practice.