CDT vs. GGT for the certification of the fitness to hold the driving license. A comparison based on the association of incremented values with the occurrence of alcohol-related road traffic accidents

BACKGROUND

In the context of fitness certification to hold the driving license, GGT and CDT have been used, sometimes in combination (γ-CDT), to exclude chronic alcohol abuse. The present study was carried out with the aim of comparing the power of these biomarkers as tools for the objective screening of subjects at high risk of alcohol-associated traffic injuries.

METHODS

288 male drivers admitted to hospital after traffic accidents were examined by determination of GGT, CDT and BAC. The degree of association of GGT, CDT and γ-CDT with BAC was analysed using non-parametric statistics.

RESULTS

Partitioning the cases using the cut-off concentrations of 0.5 g/L for BAC (the legal limit adopted in most European countries), 55 U/L for GGT and 1.9% for CDT, a highly significant difference was found between the frequency of elevated GGT or CDT in cases where BAC was within the legal limits and those with elevated BAC values (Fisher's exact test: p < 0.001). However, the calculation of the odds ratio showed a much higher increase for CDT (28 times) than for GGT (6 times) in those drivers with a BAC above the Italian legal limit in comparison with those showing a BAC within the cut-off; conversely, γ-CDT does not provide any significant advantage vs. CDT alone.

CONCLUSIONS

Both GGT and CDT provide objective evidence of an association with the occurrence of alcohol-related severe traffic accidents, but CDT shows superior association with these events. Therefore, CDT, notwithstanding higher costs, should be preferred in a forensic/certification context.

Biomarkers for alcohol abuse/withdrawal and their association with clinical scales and temptation to drink. A prospective pilot study during 4-week residential rehabilitation

A bulk of evidence in the field of translational medicine applied to clinical toxicology and rehabilitation has highlighted the possibility of using biomarkers as a support in the diagnosis of alcohol-related diseases and in monitoring of alcohol withdrawal. In a cohort of 55 subjects admitted to a 4-week residential rehabilitation period for alcohol detoxification, we applied a complementary approach correlating novel and conventional peripheral blood and urine parameters in combination with clinical and functional evaluation, contextually considered with the patient's history. Biomarkers of oxidative, inflammatory, hepatic, and neurochemical effects paralleled by alcohol craving and clinical scale measurements were determined at two specific time points, i.e., admission and discharge. Concerning the post-discharge assessment (i.e., relapse evaluation one month after discharge), a follow-up oral interview during a clinical examination was applied to evaluate alcohol abstinence.Selected biomarkers, i.e., MCP1, F2-IsoPs, and SOD1, were altered in chronic alcoholics at admission, and then showed a clearly changing trend during hospitalization. Our findings demonstrated that these specific non-traditional biomarkers, measured together with more conventional ones (e.g., CDT, EtG, IL8, ALT, AST, GGT), could represent novel key parameters for monitoring alcohol use disorders and withdrawal, being also suggestive of the complexity of the psychoneuroimmune response to alcohol. A general improvement in psychological functioning (i.e., decreases in anxiety, depression, and psychological distress) was also revealed during the 4-week rehabilitation treatment, paralleled by an increase of well-being and positive changes in terms of scores. Moreover, a positive association between SOD1 and drink craving at admission was evidenced. Notably, both SOD1 and well-being displayed a significant relation with lower risk of alcohol relapse one month after discharge, indicating that SOD1 is a good predictor of reduced relapse probability. This 4-week residential rehabilitation protocol represents a sound strategy enabling identification of alcohol use disorders and monitoring of alcohol addiction state and withdrawal. However, it has to be emphasized that results derived from this pilot study need to be extensively validated in large and independent cohorts of subjects.

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.

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.

Asialo-transferrin: Biochemical aspects and association with alcohol abuse investigation

Asialo-human transferrin (asialo-hTf) is a glycoform of the human serum protein transferrin characterized by the lack of the sialic acid (SA) terminal unit. It is known that glycosylation micro-heterogeneity and the presence of SA are strongly involved in protein functioning and pathophysiological activities. Some hTf glycoforms are valuable biomarkers for the detection of both genetic defects of glycosylation and/or sialoform distribution changes. The detection of the carbohydrate deficient transferrin (CDT) glycoforms is currently a widely employed method for the diagnosis of chronic alcohol abuse. The physiological significance of asialo-hTf is still unclear, despite its important biological implications. The current knowledge suggests that asialo-hTf may be involved in regulation of iron transport and release at the hepatic level, which, consequently, could strongly be affected by alcohol consumption. For these reasons, a deeper understanding of asialo-hTf structure and its physiological role is required, and an improved method of its analysis would favor the detection of both chronic abuse and other habits of alcohol intake and/or misuse. Thus, suitable analytical methods possessing higher sensitivity and specificity in comparison with the currently available techniques are certainly recommended. The present review summarizes the studies on asialo-hTf structure, roles, and detection techniques mainly in relation to its possible use as a potentially additional useful biomarker of alcohol abuse, and underlines its prospective value as a forensic and diagnostic tool.

Critical Evaluation of the Association Between Elevated Mean Corpuscular Volume and Alcohol-Related Traffic Accidents: A Retrospective Study on 6244 Car Crash Cases

BACKGROUND

Erythrocyte mean corpuscular volume (MCV) has been used for decades as a biomarker of chronic alcohol abuse and in the treatment of alcohol dependence. More recently, it has also been adopted to investigate the fitness of subjects to hold the driving license to prevent traffic accidents. So far, however, the studies on the association of MCV with an increased risk of alcohol-associated car accidents are extremely scarce, if not totally absent. To the best of our knowledge, the present work is the first specifically aimed at studying a plausible association between elevated MCV and crash accidents correlated with alcohol abuse.

METHODS

A total of 6,244 drivers involved in traffic accidents underwent mandatory laboratory analyses including blood alcohol concentration (BAC) determination and MCV analysis. BAC and MCV determinations were performed by headspace gas chromatography and complete blood count, respectively.

RESULTS

The chi-square test evaluating the proportions of subjects with elevated MCVs (>95 fl) yielded a highly significant result (χ²  = 68.0; p < 0.001) in the blood samples where the BAC was above the legal limit (i.e., >0.5 g/l). However, when considering only drivers showing BACs in the range of 0.51 to 1.5 g/l, the frequencies of elevated MCV values are fairly comparable (χ²  = 0.062, p = 0.80). In contrast, limiting the evaluation to BACs > 1.5 g/l, the frequency of elevated MCVs raised to 19.1% (χ²  = 58.9, p value < 0.001 vs. the group with BAC within the legal limits).

CONCLUSIONS

The present observations show that MCV increases are typically associated with drivers involved in accidents only if driving under severe alcohol intoxication, leading to a preliminary conclusion that, in the context of the certification of the fitness to the driving license, MCV fails to reveal individuals at risk who tend to drive in a condition of low-to-moderate alcohol intoxication.

Carbohydrate-Deficient Transferrin as a Biomarker for Screening At-Risk Drinking in Elderly Men

Background

Carbohydrate-deficient transferrin (CDT) is a useful biomarker to identify excessive alcohol consumption; however, few studies have validated the %CDT cut-off value in elderly men. This study estimated the optimal %CDT cut-off value that could identify excessive alcohol consumption in men aged ≥65 years.

Methods

This retrospective study included 120 men who visited the department of family medicine at Chungnam National University Hospital for health check-up between January 2010 and August 2013. At-risk drinking included heavy- and binge drinking. Heavy drinking was defined as more than seven standard drinks/wk, and binge drinking was defined as more than three standard drinks/d. The cut-off %CDT values for at-risk drinking were determined using receiver operating characteristic (ROC) curves.

Results

Based on the ROC curves, the optimal %CDT cut-off values in ≥65-year-old men were 1.95% for at-risk drinking, 1.81% for heavy drinking, and 2.07% for binge drinking. The sensitivity, specificity, and positive and negative predictive values were 58.7%, 83.6%, 69.2%, and 76.2% for at-risk drinking, respectively. The AUROC were >0.7 for all three evaluated cut-offs.

Conclusion

Our results suggest that the %CDT cut-off value for at-risk drinking in elderly Korean men (≥65 years) should be readjusted to a lower value of 1.95%.

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

The need for investigating alcohol abuse by means of objective tools is worldwide accepted. Among the currently available biomarkers of chronic alcohol abuse, carbohydrate-deficient transferrin (CDT) is one of the most used indicator, mainly because of its high specificity. However, some CDT analytical and interpretation aspects are still under discussion, as witnessed by numerous research papers and reviews. The present article presents a critical review of the literature on CDT appeared in the period from 2007 to 2017 (included). The article is organized in the following sections: (1) introduction, (2) pre-analytical aspects (3) analytical aspects (4) diagnostic aspects (5) concluding remarks. As many as 139 papers appeared in the international literature and retrieved by the search engines PubMed, Web of Science and Scopus are quoted.

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.

A comparison between serum carbohydrate-deficient transferrin and hair ethyl glucuronide in detecting chronic alcohol consumption in routine

AIMS

In heavy alcohol consumption laboratory tests represent an objective evidence. In this study we compared older and newer biomarkers in blood and in hair.

METHODS

Carbohydrate-deficient transferrin (CDT), ethyl glucuronide (EtG), AST, ALT, GGT, MCV were measured in a large sample (n = 562). All people declared no alcohol consumption within the last 3 months. Serum CDT was measured by the candidate HPLC reference method and expressed as relative amount of disialotransferrin (%DST: cutoff 1.7%). EtG was measured in hair by a validated in-house method by LC-MS/MS (cutoff 30 pg/mg).

RESULTS

Respectively, 42 (7.5%) and 76 (13.5%) subjects were positive to CDT and EtG. In particular, 30 (5.3%) subjects were positive to both tests, 12 (2.1%) only to CDT, while 46 (8.2%) only to EtG. The agreement (positive and negative pairs) between CDT and EtG was 89.7%. Interestingly, 6 out of 12 (50%) CDT-positive subjects had EtG < 15 pg/mg, whereas 27 out of 46 (59%) EtG-positive subjects had CDT < 1.1%. Forty-one out of 76 (54%) EtG-positive subjects display EtG values within 30-50 pg/mg.

CONCLUSION

Large variability exists between CDT and EtG in detecting chronic alcohol consumption. We suggest to use CDT, or a combination of different biomarkers, to identify alcohol abuse in a forensic context. EtG results close to the cutoff (30-50 pg/mg) should be cautiously considered before any sanction is assigned.

Screening for alcohol and drug use disorders among adults in primary care: a review

BACKGROUND: The Patient Protection and Affordable Care Act of 2010 supports integration of substance abuse interventions and treatments into the mainstream health care system. Thus, effective screening and intervention for substance use disorders in health care settings is a priority. OBJECTIVE: This paper reviews the prevalence of alcohol and drug use disorders (abuse or dependence) in primary care settings and emergency departments, as well as current screening tools and brief interventions. METHODS: MEDLINE was searched using the following keywords: alcohol use, alcohol use disorder, drug use, drug use disorder, screening, primary care, and emergency departments. Using the related-articles link, additional articles were screened for inclusion. This review focuses on alcohol and drug use and related disorders among adults in primary care settings. CONCLUSION: Screening, brief intervention, and referral for treatment are feasible and effective in primary care settings, provided that funding for screening is available, along with brief interventions and treatment facilities to which patients can be referred and treated promptly.

High performance liquid chromatography evaluation of serum carbohydrate-deficient transferrin and more sialylated transferrin glycoforms in children

OBJECTIVES

The evaluation of the age-specific distribution of transferrin glycoforms in paediatric patients may help in defining reference intervals which are critical for an improved and earlier diagnosis.

DESIGN AND METHODS

Serum samples from 224 children (age: 2 months-14 years) were analyzed by HPLC (Bio-Rad CDT/HPLC kit) and glycoforms expressed as percentage of the total area of transferrin (Tf).

RESULTS

Asialo- and Monosialo-Tf were not detectable in any patient. Medians (IQR) were respectively 0.92% (0.80-1.04%) for Disialo-Tf; 3.47% (2.69-4.18%) for Trisialo-Tf; 82.54% (81.32-83.53%) for Tetrasialo-Tf; 12.73% (11.91-14.09%) for Pentasialo-Tf. Statistically significant differences in Trisialo-Tf (p < 0.0005), Tetrasialo-Tf (p = 0.001), Pentasialo-Tf (p < 0.0005), but not in Disialo-Tf, were observed between the age groups.

CONCLUSIONS

Age-specific Disialo-Tf cut-offs are not necessary. In children 1.3% and 6.4% may be suggested as upper limits of normal range to detect increases of Disialo- and Trisialo-Tf. The presence of Asialo- and Monosialo-Tf should be considered an abnormal finding and prompt further investigations.

Chronic excessive alcohol consumption diagnosis: comparison between traditional biomarkers and ethyl glucuronide in hair, a study on a real population

BACKGROUND

The study aimed to evaluate the diagnostic sensitivity (SE) and specificity (SP) of chronic alcohol misuse diagnosis by comparing traditional biomarkers with ethyl glucuronide (EtG), an ethanol direct metabolite, detected in the keratinic matrix.

METHODS

Seventy-six subjects tested for chronic alcohol abuse for different purposes were recruited. EtG was detected in hair, whereas the analyses of carbohydrate-deficient transferrin (CDT), alanine transaminase, aspartate transaminase, gamma-glutamyl transferase, mean corpuscular volume, and mean corpuscular hemoglobin were performed in serum samples.

RESULTS

Of the 76 patients examined, 26 were judged by the medical doctors as subjects with alcohol abuse problems and, therefore, not eligible for driving license renewal or liver transplant. EtG in hair (SE = 0.68, SP = 1.00) showed the best diagnostic SE and SP compared with the other biomarkers investigated. Among the traditional biomarkers, only CDT proved to be suitable for forensic purposes because of the high diagnostic specificity (SP = 1.00) although it showed poor diagnostic SE (0.27). The percentage of positive samples decreased for all the biomarkers by excluding the subjects with hepatic diseases, except for EtG and CDT, suggesting that these 2 biomarkers could be less affected by false positive results, because of hepatic diseases.

CONCLUSIONS

This study showed that when EtG in hair and CDT results are combined, diagnostic SE in chronic alcohol abuse diagnosis clearly improved, suggesting that complementary analysis of both these biomarkers provides the best diagnostic tool in suspected cases of chronic excessive alcohol consumption.

Pregnancy and variations of carbohydrate-deficient transferrin levels measured by the candidate reference HPLC method

AIMS

Contrasting data are available on the diagnostic accuracy of carbohydrate-deficient transferrin (CDT) during pregnancy. These differences may depend in part on how CDT was evaluated and expressed. Here, we report on variations of CDT levels in pregnant women using the high performance liquid chromatography (HPLC) candidate reference method.

METHODS

Alanine aminotransferase, aspartate aminotransferase, gamma-glutamyltransferase, mean corpuscular volume, serum transferrin, urine and serum ethyl glucuronide and CDT were measured in 64 women, self-reporting as non-alcohol abusers (age: median 34, IQR: 28-38), at different stages of normal pregnancy (gestational weeks: median 28, IQR: 8-33). CDT was expressed as percentage of disialotransferrin to total transferrin (%CDT).

RESULTS

Transferrin was associated with both %CDT (r = 0.66; P < 0.001) and gestational week (r = 0.68; P < 0.001). Interestingly, %CDT was highly correlated with gestational week (r = 0.77; P < 0.001), even after controlling for the effect of transferrin. Moreover, statistically significant differences in %CDT were also evident between women grouped for pregnancy trimester (first trimester: mean 1.01% (SD 0.19); second trimester: 1.30% (SD 0.14); third trimester: 1.53% (SD 0.22); ANOVA P < 0.001). Trend analysis confirmed a proportional increase of %CDT along with pregnancy trimesters (P < 0.001).

CONCLUSIONS

%CDT, measured with the HPLC candidate reference method, is independently associated with gestational week. Differently from what has been previously reported or expected, the relationship between pregnancy and CDT could be more complex. The diagnostic accuracy of CDT for detecting alcohol abuse in a legal context may be limited in pregnant women and the effect of gestational age should be considered.

Effect of detoxification on liver stiffness assessed by Fibroscan® in alcoholic patients

AIMS

The aims of this study were to determine whether alcohol consumption or cessation influences transient elastography (TE) measurements and whether TE is a useful tool to monitor alcoholic patients.

PATIENTS

Twenty-three consecutive heavy drinkers (20 men and 3 women; mean age 47.2 years) admitted for a 7-day hospitalization for alcohol detoxification were included. On admission (D0), a detailed medical history was taken and the following laboratory tests were performed [aspartate aminotransferase (ASAT), gamma glutamyltransferase (γGT), and carbohydrate-deficient transferrin (CDT) levels, and Fibroscan(®)]. All examinations were repeated on D8, D30, and D60. Variation in the median Fibroscan value of >20% was considered significant.

RESULTS

After 1 week of detoxification, the % variation in TE was -21.67 ± -27.6%. The median variation in TE between D8 and D60 was -20% in the abstinent group and 32% in the relapse group (p = 0.007). An increase in proportion of patients with a significant decrease in TE was observed with an increased duration of abstinence: 41.7% at D8 and 66.7% at D60. TE values were significantly correlated with ASAT, γGT, and CDT at D0 and D8, and with ASAT and γGT at D60.

CONCLUSIONS

TE in alcoholics is influenced by major variations in the biochemical activity of the disease. The kinetics of variation of TE suggest that this method may be useful to assess alcohol abuse and control.

Biomarker testing to estimate under-reported heavy alcohol consumption by persons with HIV initiating ART in Uganda

Alcohol affects the transmission and treatment of HIV, yet may be under-reported in resource-limited settings. We compared self-reported alcohol consumption with levels of plasma carbohydrate-deficient transferrin (%CDT), a biomarker of heavy alcohol consumption, in persons initiating antiretroviral therapy in Uganda. Almost seven percent (6.7%) of persons reporting abstaining and 10% reporting consuming 1–40 drinks in the prior month tested positive for %CDT, and actual under-report may be higher due to low sensitivity of %CDT. These results suggest likely under-report in those reporting abstaining and current drinking. Improved identification of heavy alcohol consumption is needed for research and clinical purposes.