Laboratory Markers Carbohydrate-Deficient Transferrin, γ-Glutamyltransferase, and Mean Corpuscular Volume Are Not Useful as Screening Tools for High-Risk Drinking in the General Population: Results From the Study of Health in Pomerania (SHIP)

Alcohol associated liver disease 2020: A clinical practice guideline by the Italian Association for the Study of the Liver (AISF)

Alcohol use disorder which includes alcohol abuse and dependence represents one of the leading risk factors for premature mortality in Europe and it is responsible of over 200 conditions, including neuropsychiatric disorders, chronic diseases, cancers and accidents leading to permanent disability. Alcohol use disorder represents the most common cause of liver damage in the Western world, with a wide spectrum of diseases ranging from steatosis, steatohepatitis, fibrosis, cirrhosis and cancer. The present clinical practice guidelines by the Italian Association for the Study of the Liver (AISF) are focused on the current knowledge about epidemiology, pathophysiology, clinical features, diagnosis and treatment of alcohol associated liver disease, aiming to provide practical recommendations on the management of this complex pathological condition.

Circulating angiopoietin-2 and its soluble receptor Tie-2 concentrations are related to inflammatory markers in the general population

BACKGROUND

The Angiopoietin/Tie (Tyrosine kinase with Ig and EGF homology domains) signaling axis has crucial influences on angiogenesis and the vasculature's reorganization. Moreover, angiopoietin-2 (Ang2) is discussed as a biomarker for diseases' severity and development. Previous studies reported increased Ang2 levels in patients with inflammatory diseases and associations of Ang2 with inflammation markers in relatively small samples. We aimed to assess the relation of Ang2 and Tie2 with inflammation markers in the general population.

METHODS AND RESULTS

Data of 6624 participants of the population-based Study of Health in Pomerania (SHIP-1) and the independent SHIP-Trend were used. Ang2, Tie2 and inflammatory biomarkers, including fibrinogen, high-sensitive C-reactive protein (hsCRP) and white blood cell count (WBC), were measured. Adjusted analysis of variance (ANOVA) and linear/logistic regression models were performed in the entire sample and in individuals free of hypertension and diabetes. ANOVA [adjusted means of the 1st vs. 4th Ang2 quartile: fibrinogen 3.0 vs. 3.2 g/l; hsCRP 1.2 vs. 1.6 mg/l; WBC 5.9 vs. 6.6 Gpt/l] and regression models adjusted for potential confounders revealed positive relations of Ang2 with all considered inflammation markers. These associations persisted after the exclusion of individuals with hypertension and diabetes. In contrast, Tie2 showed no clear association pattern with the investigated inflammatory markers even if a trend toward a positive relation with fibrinogen became apparent.

CONCLUSION

Ang2 was positively associated with fibrinogen, hsCRP and WBC in a large population-based setting. These findings partly agree with previous results, largely obtained in clinical samples. Ang2 has diverse postulated effects on inflammation processes, like increase of vascular leakage or influences on the adhesion of leukocytes to the vessel wall. The proinflammatory character of these effects is similar to these of fibrinogen which conforms to our findings of relations between the markers. However, further research is needed to elucidate possible functional mechanisms.

Endogenous Androgens and Sex Hormone-Binding Globulin in Women and Risk of Metabolic Syndrome and Type 2 Diabetes

CONTEXT AND OBJECTIVES

The association of endogenous androgens and sex hormone-binding globulin (SHBG) with metabolic syndrome (MetS) and type 2 diabetes mellitus (T2DM) mostly 23562 refers to small and selected study samples with immunoassay-based measurements. Thus, we investigated the association of hormone levels with MetS and T2DM in women from a large population-based sample.

DESIGN, SETTING, AND PARTICIPANTS

A total of 2077 women from the Study of Health in Pomerania were assessed at baseline (N = 3160, 1997-2001) and 5-year follow-up (N = 1711, 2002-2006).

MAIN OUTCOMES AND MEASURES

We investigated associations of total testosterone (T) and androstenedione measured by liquid chromatography-tandem mass spectrometry, SHBG by immunoassay, and free T and free androgen index with MetS and T2DM.

RESULTS

Baseline prevalence of MetS and T2DM was 23.1% (N = 365) and 9.5% (N = 196), with an incidence of 17.7 and 7.0 per 1.000 person-years, respectively. Cross-sectional analyses yielded inverse associations of SHBG with MetS (relative risk [RR], 0.67; 95% confidence interval [CI], 0.60-0.74) and T2DM (RR, 0.61; 95% CI, 0.50-0.74) after multivariable adjustment. In longitudinal analyses, only age-adjusted models showed an inverse association of baseline SHBG with incident MetS (RR, 0.61; 95% CI, 0.51-0.73) and T2DM (RR, 0.58; 95% CI, 0.43-0.78). Multivariable-adjusted models stratified by menopausal status revealed an inverse association between SHBG and incident MetS risk in postmenopausal women (RR, 0.65; 95% CI, 0.51-0.81).

CONCLUSIONS

This longitudinal population-based study revealed independent inverse associations of SHBG with MetS and T2DM, suggesting low SHBG as a potential risk marker for cardiometabolic morbidity, especially among postmenopausal women.

Association of sex hormones with incident 10-year cardiovascular disease and mortality in women

OBJECTIVES

The aims of this study were to ascertain whether women with high levels of serum total testosterone (TT) or low levels of sex hormone-binding globulin (SHBG) are more likely to develop cardiovascular disease (CVD), and to investigate potential associations between sex hormones and mortality (all-cause, as well as cause-specific) in the general population.

STUDY DESIGN AND MAIN OUTCOME MEASURES

Data on 2129 women with a mean age of 49.0 years were obtained from the population-based Study of Health in Pomerania over a median follow-up of 10.9 years. Associations of baseline levels of TT, SHBG, and rostenedione (ASD), and free testosterone (fT), and of the free androgen index (FAI), with follow-up CVD morbidity, as well as all-cause and CVD mortality, were analyzed using multivariable regression modeling.

RESULTS

At baseline the prevalence rate of CVD was 17.8% (378 women) and the incidence of CVD over the follow-up was 50.9 per 1000 person-years. We detected an inverse association between SHBG and baseline CVD in age-adjusted models (relative risk per standard deviation increase: 0.83; 95% confidence interval: 0.74-0.93). We did not detect any significant associations between sex hormone concentrations and incident CVD in age- and multivariable-adjusted Poisson regression models. Furthermore, none of the sex hormones (TT, SHBG, ASD, fT, FAI) were associated with all-cause mortality.

CONCLUSIONS

This population-based cohort study did not yield any consistent associations between sex hormones in women and incident CVD or mortality risk.

Proteomic approaches and identification of novel therapeutic targets for alcoholism

Recent studies have shown that gene regulation is far more complex than previously believed and does not completely explain changes at the protein level. Therefore, the direct study of the proteome, considerably different in both complexity and dynamicity to the genome/transcriptome, has provided unique insights to an increasing number of researchers. During the past decade, extraordinary advances in proteomic techniques have changed the way we can analyze the composition, regulation, and function of protein complexes and pathways underlying altered neurobiological conditions. When combined with complementary approaches, these advances provide the contextual information for decoding large data sets into meaningful biologically adaptive processes. Neuroproteomics offers potential breakthroughs in the field of alcohol research by leading to a deeper understanding of how alcohol globally affects protein structure, function, interactions, and networks. The wealth of information gained from these advances can help pinpoint relevant biomarkers for early diagnosis and improved prognosis of alcoholism and identify future pharmacological targets for the treatment of this addiction.

Cross-sectional and longitudinal associations between insulin-like growth factor I and metabolic syndrome: a general population study in German adults

BACKGROUND

A previous study showed an inverse association between the insulin-like growth factor I (IGF-I) and the risk of impaired glucose tolerance or diabetes mellitus. Moreover, myocardial infarction patients with high baseline IGF-I levels had a lower risk of diabetes mellitus. These data suggested a protective effect of IGF-I against the development of metabolic syndrome. However, there are no longitudinal data regarding IGF-I and metabolic syndrome. The aim of the present study was to investigate the longitudinal association between IGF-I and metabolic syndrome.

METHODS

Data from the population-based Study of Health in Pomerania, Germany, were used for cross-sectional (n = 3903) and longitudinal (n = 2143) analyses (5-year follow-up). Metabolic syndrome was defined by three or more of the following five components: abdominal obesity, elevated triglycerides, reduced high-density lipoprotein cholesterol, elevated blood pressure and elevated nonfasting glucose. Serum IGF-I and IGF binding protein 3 (IGFBP-3) were determined by chemiluminescence immunoassays. Logistic and Poisson regression analyses were performed to determine associations.

RESULTS

In cross-sectional analyses high IGFBP-3 as well as high and low IGF-I/IGFBP-3 ratio levels were associated with prevalent metabolic syndrome. In longitudinal analyses, the direction of the relation changed: men but not women with high IGF-I or IGF-I/IGFBP-3 ratio levels had an increased, whereas men with low levels had a decreased risk of incident metabolic syndrome.

CONCLUSION

In concordance with previous studies, our cross-sectional analyses showed a relation between low IGF-I/IGFBP-3 ratio and the prevalence of metabolic syndrome. In contrast, the longitudinal analyses indicated that a high IGF-I level was a risk marker for incident metabolic syndrome.

Low testosterone concentrations in men contribute to the gender gap in cardiovascular morbidity and mortality

BACKGROUND

Across the industrialized world, men experience an earlier onset of cardiovascular disease (CVD) and a life expectancy 5 to 10 years shorter than women. Low total testosterone (TT) concentrations in men have been suggested as a novel CVD risk factor, but its contribution to this gender gap is less well studied.

METHODS

We used data of 4152 individuals (2113 women and 2039 men) aged 20 to 79 years from the longitudinal population-based cohort Study of Health in Pomerania, Germany. Multivariable Poisson and Cox proportional hazard regression models were used to investigate the risk of incident cardiovascular morbidity (5-year examination follow-up), as well as all-cause and CVD mortality (10-year follow-up) between men and women. Additionally, the added risk attributable to low TT in men (<10th percentile) was assessed.

RESULTS

Compared with women, men were uniformly at higher risk of incident cardiovascular morbidity, including overweight, hypertension, dyslipidemia, metabolic syndrome, and type 2 diabetes mellitus. Men were also at increased all-cause mortality (hazard ratio = 2.05; 95% CI, 1.61-2.60) and 10-year CVD risk compared with women. In subgroup analyses, men with low TT showed the highest 10-year CVD and mortality risk compared with both men with higher TT and women. TT was also negatively associated with cardiovascular risk as defined by the Framingham risk score (P < 0.001), after multivariable adjustment.

CONCLUSIONS

Analyzing a large population-based sample, we observed that men have a generally higher risk of incident cardiovascular morbidity and mortality. Furthermore, men with low TT concentrations were identified as high-risk individuals with regard to 10-year CVD and mortality risk.

Diagnosis and management of alcoholic hepatitis

Alcoholic hepatitis is a form of severe, cholestatic liver disease that results from consumption of large amount of alcohol during a sustained period of time in a subset of alcoholics. Symptoms could be mild and nonspecific to more severe. The diagnosis of alcoholic hepatitis can be made with a thorough history, physical examination, and review of laboratory results. Liver biopsy is confirmatory but generally not indicated for the diagnosis. Abstinence is the key form of therapeutic intervention. Despite variable results in clinical trials, corticosteroids and pentoxifylline seem to provide moderate survival benefit. Liver transplantation in acute alcoholic hepatitis is contentious.

Mendelian randomization suggests non-causal associations of testosterone with cardiometabolic risk factors and mortality

Prospective studies showed that low serum testosterone concentrations are associated with various cardiometabolic risk factors and mortality. However, the causal nature of these associations is controversial. We studied 1 882 men aged 20-79 years with serum testosterone concentrations and genotyping data from the longitudinal population-based Study of Health in Pomerania. Testosterone concentrations were cross-sectionally associated with cardiometabolic risk factors, including anthropometric, lipid, blood pressure and glycaemic parameters; and prospectively with all-cause mortality (277 deaths, 14.7%) during the 10-year follow-up. To overcome problems of residual confounding, reverse causation, or regression dilution bias in the investigated testosterone-outcome associations, we used two-stage least square regression models with previously identified polymorphisms at the SHBG gene (rs12150660) and X chromosome (rs5934505) as multiple genetic instruments in an instrumental variable (IV) approach, also known as Mendelian randomization. In standard regression analyses, testosterone was robustly associated with a wide range of cardiometabolic risk factors. In subsequent IV analyses, no such significant associations were observed. Similarly, prospective analyses showed a consistent association of low testosterone concentrations with increased all-cause mortality risk, which was not apparent in subsequent IV analyses. The present Mendelian randomization analyses did not detect any evidence for causal associations of testosterone concentrations with cardiometabolic risk factors and mortality, suggesting that previously reported associations might largely result from residual confounding or reverse causation. Although testosterone assessment might improve risk prediction, implementation of testosterone replacement therapy requires further evidence of a direct effect on cardiometabolic outcomes from double-blinded randomized controlled trials and large-scale Mendelian randomization meta-analyses.

Inverse association between total testosterone concentrations, incident hypertension and blood pressure

BACKGROUND

Studies on the relationship between testosterone concentrations and blood pressure have yielded inconsistent results. Therefore, this study investigated the prospective association of total testosterone (TT) concentrations with risk of incident hypertension and blood pressure change in 1,484 men aged 20-79 years.

METHODS

Data from the population-based Study of Health in Pomerania, Germany, were used. Serum TT concentrations, measured by chemiluminescent enzyme immunoassays, were categorised into age-specific quartiles. Generalised Estimating Equation (GEE) models, adjusted for age, waist circumference, physical activity, smoking and alcohol consumption were specified.

RESULTS

During a median follow-up time of 5.0 years, the prevalence of hypertension increased from 50.6% to 57.1%. TT concentrations were significantly lower in men with baseline and incident hypertension. Analyses revealed that men with baseline TT concentrations in the lowest quartile had an increased risk of incident hypertension (odds ratio (OR), 1.19 (95% CI, 1.10-1.28)) compared to men with higher TT concentrations. Furthermore, we found a significant inverse association of TT concentrations and blood pressure, showing that men with baseline TT concentrations in the lowest quartile showed the slightest change in systolic blood pressure (-6.01 mmHg), diastolic blood pressure (-2.11 mmHg) and pulse pressure (-3.98 mmHg). Sensitivity analyses in a subpopulation of men without antihypertensive medication confirmed these findings.

CONCLUSION

These results show that low male TT concentrations are predictive of hypertension, suggesting TT as a potential biomarker of increased cardiovascular risk.

Self-perceived quality of life predicts mortality risk better than a multi-biomarker panel, but the combination of both does best

Background

Associations between measures of subjective health and mortality risk have previously been shown. We assessed the impact and comparative predictive performance of a multi-biomarker panel on this association.

Methods

Data from 4,261 individuals aged 20-79 years recruited for the population-based Study of Health in Pomerania was used. During an average 9.7 year follow-up, 456 deaths (10.7%) occurred. Subjective health was assessed by SF-12 derived physical (PCS-12) and mental component summaries (MCS-12), and a single-item self-rated health (SRH) question. We implemented Cox proportional-hazards regression models to investigate the association of subjective health with mortality and to assess the impact of a combination of 10 biomarkers on this association. Variable selection procedures were used to identify a parsimonious set of subjective health measures and biomarkers, whose predictive ability was compared using receiver operating characteristic (ROC) curves, C-statistics, and reclassification methods.

Results

In age- and gender-adjusted Cox models, poor SRH (hazard ratio (HR), 2.07; 95% CI, 1.34-3.20) and low PCS-12 scores (lowest vs. highest quartile: HR, 1.75; 95% CI, 1.31-2.33) were significantly associated with increased risk of all-cause mortality; an association independent of various covariates and biomarkers. Furthermore, selected subjective health measures yielded a significantly higher C-statistic (0.883) compared to the selected biomarker panel (0.872), whereas a combined assessment showed the highest C-statistic (0.887) with a highly significant integrated discrimination improvement of 1.5% (p < 0.01).

Conclusion

Adding biomarker information did not affect the association of subjective health measures with mortality, but significantly improved risk stratification. Thus, a combined assessment of self-reported subjective health and measured biomarkers may be useful to identify high-risk individuals for intensified monitoring.

Molecular targets of alcohol action: Translational research for pharmacotherapy development and screening

Alcohol abuse and dependence are multifaceted disorders with neurobiological, psychological, and environmental components. Research on other complex neuropsychiatric diseases suggests that genetically influenced intermediate characteristics affect the risk for heavy alcohol consumption and its consequences. Diverse therapeutic interventions can be developed through identification of reliable biomarkers for this disorder and new pharmacological targets for its treatment. Advances in the fields of genomics and proteomics offer a number of possible targets for the development of new therapeutic approaches. This brain-focused review highlights studies identifying neurobiological systems associated with these targets and possible pharmacotherapies, summarizing evidence from clinically relevant animal and human studies, as well as sketching improvements and challenges facing the fields of proteomics and genomics. Concluding thoughts on using results from these profiling technologies for medication development are also presented.

Prevalence, incidence and risk factors of testosterone deficiency in a population-based cohort of men: results from the study of health in Pomerania

OBJECTIVE

Low total testosterone levels (TT) have been associated with increased morbidity and mortality. However, the prevalence and incidence of testosterone deficiency (TD) in association with its risk has not been assessed systematically to date.

METHODS

Data from the prospective population-based Study of Health in Pomerania were used. From the 2117 men aged 20-79 years at baseline, 1490 men with complete TT data were analysed. Crude and age-specific prevalence and incidence rates of TD were estimated by TT levels below the age-specific 10th percentile. Analysis of covariance and Poisson regression models were used to assess the association of socio-demographic characteristics, health-related lifestyle, as well as somatometric, medical and laboratory measures with risk of incident TD.

RESULTS

TD baseline prevalence was 10.4% (N = 155) and incidence 11.7 per 1000 person-years. TT levels showed a significant age-related decline with an unadjusted rate of 0.05 nmol/l per year. Obesity, metabolic syndrome, diabetes and dyslipidaemia were identified as risk factors of incident TD. Subpopulations of men without the revealed risk factors at both examinations maintained constant TT levels over time.

CONCLUSIONS

Besides aging alone, lifestyle and different comorbidities were associated with TT level decline, suggesting that the age-related TT decline may be at least partly prevented through the management of potentially modifiable risk factors and health related behaviour.

Partial misspecification of survey design features sufficed to severely bias estimates of health-related outcomes

OBJECTIVE

Surveys frequently deviate from simple random sampling through the use of unequal probability sampling, stratified sampling, and multistage sampling. This work uses a survey of public health to systematically illustrate the effects of incompletely accounting for strata, clustering, and weights.

STUDY DESIGN AND SETTING

Data analysis was based on the Study of Health in Pomerania (n=4,308, 20-79 years), a two-stage regional survey with high sampling fractions at the first stage. Effects of survey design features comprising weights, stratification, clustering, and finite population correction on point and variance estimates of lifestyle indicators and clinical parameters were assessed.

RESULTS

Misspecifications of the survey design substantially affected both the point estimates of health characteristics and their standard errors (SEs). The strongest bias in SEs concerned the omission of the second sampling stage. Ignoring the sampling design led to minor differences in variance estimates from the complete setup. Weighting predominantly affected point estimates of lifestyle factors.

CONCLUSION

A partial misspecification of survey design elements may bias variance estimates severely and is sometimes even more harmful compared with completely neglecting design elements. If subgroups are sampled at different rates, weighting is of particular relevance with regard to prevalence estimates of lifestyle indicators.

Alcoholic liver disease

These recommendations provide a data-supported approach. They are based on the following: (i) a formal review and analysis of the recently published world literature on the topic (Medline search); (ii) American College of Physicians Manual for Assessing Health Practices and Designing Practice Guidelines (1); (iii) guideline policies, including the American Association for the Study of Liver Diseases (AASLD) Policy on the development and use of practice guidelines and the AGA Policy Statement on Guidelines (2); and (iv) the experience of the authors in the specified topic. Intended for use by physicians, these recommendations suggest preferred approaches to the diagnostic, therapeutic, and preventive aspects of care. They are intended to be flexible, in contrast to the standards of care, which are inflexible policies to be followed in every case. Specific recommendations are based on relevant published information. To more fully characterize the quality of evidence supporting the recommendations, the Practice Guideline Committee of the AASLD requires a Class (reflecting the benefit vs. risk) and Level (assessing the strength or certainty) of Evidence to be assigned and reported with each recommendation (Table 1, adapted from the American College of Cardiology and the American Heart Association Practice Guidelines) (3,4).

Ultrasonographic hepatic steatosis increases prediction of mortality risk from elevated serum gamma-glutamyl transpeptidase levels

The aim of the present study was to investigate the association of serum gamma-glutamyltransferase (GGT) levels with all-cause mortality and to assess the impact of ultrasonographic findings of hepatic hyperechogenicity in that association. We used data from 4,160 subjects (2,044 men and 2,116 women) recruited for the population-based Study of Health in Pomerania (SHIP) without baseline hepatitis B and C infections or liver cirrhosis. GGT was divided into age- and sex-dependent quintiles to calculate overall and sex-specific crude incidence mortality rates. Hepatic steatosis was defined by elevated GGT levels (>80%) and the presence of hyperechogenic liver ultrasound. We used multiple-adjusted Cox proportional hazards regression models, first, to assess the direct effect of GGT on all-cause mortality, second, to stratify according to the ultrasonographic finding, and third, to investigate potential mediating effects of cardiometabolic risk factors. During 29,810 person-years (7.3 years, median) of follow-up, 307 individuals (7.5%) died, resulting in a death rate of 0.86 deaths per 1000 person-years. Elevated GGT levels were associated with increased risk of mortality in men (hazard ratio [HR] 1.49; 95% confidence interval [CI], 1.08-2.05), but not in women (HR 1.30; 95% CI, 0.80-2.12). This association was even stronger in men with hepatic steatosis (HR 1.98; 95% CI, 1.21-3.27). Cause-specific mortality analysis by cardiovascular disease deaths confirmed the sex-specific association. Adjustment for cardiometabolic risk factors did not affect the estimates.

CONCLUSION

In the case of increased GGT levels, liver ultrasound should be performed, not only for diagnosis, but also for further risk stratification.

Prediction of metabolic syndrome by low serum testosterone levels in men: results from the study of health in Pomerania

OBJECTIVE

The aim of this analysis was to assess the prospective association of serum testosterone and dehydroepiandrosterone sulfate (DHEAS) levels with incident metabolic syndrome (MetS) in men.

RESEARCH DESIGN AND METHODS

Data were obtained from the Study of Health in Pomerania (SHIP), a population-based prospective cohort of adults aged 20-79 years. Analyses were conducted in 1,004 men without baseline MetS defined by National Cholesterol Education Program Adult Treatment Panel III guidelines. Testosterone and DHEAS were categorized by age-specific quartiles and Poisson regression models with relative risks (RRs) and 95% CIs were estimated.

RESULTS

After a median follow-up time of 5.0 years, 480 men (47.8%) developed MetS. Testosterone levels decreased with increasing number of MetS components. Testosterone in the lowest quartile predicted MetS (RR 1.38 [95% CI 1.13-1.69]), particularly among men aged 20-39 years (2.06 [1.29-3.29]), even after adjustment for age, smoking, alcohol consumption, physical activity, waist circumference, self-related health, and time of blood sampling. DHEAS levels were not related to incident MetS (0.99 [0.83-1.19]).

CONCLUSIONS

Low testosterone but not DHEAS predicts development of MetS in a population-based cohort of 1,004 men aged 20-79 years. Especially in young men aged 20-39 years, results suggest low testosterone as a strong predictor for incident MetS. Assessment of testosterone in young and middle-age men may allow early interventions in the general population.

Hepatic steatosis is associated with low serum testosterone and high serum DHEAS levels in men

Obesity and metabolic syndrome are associated with low serum testosterone levels. Hepatic steatosis contributes to the metabolic syndrome and might be regarded as its hepatic manifestation. In this study, we sought to investigate the relationship between hepatic steatosis, serum testosterone and dehydroepiandrosterone sulphate (DHEAS) levels in men. This is a cross-sectional population-based study. We used data of 1912 men recruited for the population-based Study of Health in Pomerania, which was conducted in a region with high prevalence of metabolic syndrome and related diseases. Hepatic steatosis was defined according to sonographic criteria. The relationship of hepatic steatosis with serum testosterone and DHEAS levels was analysed by multivariable logistic regression. Men with low serum testosterone levels had a higher risk of hepatic steatosis than men with high serum testosterone levels. Adjustment for age and further confounders attenuated this association, but did not affect statistical significance (odds ratio 2.36; 95% confidence interval 1.66-3.37; p < 0.05). In the full model, the highest risk of hepatic steatosis was found in subjects with the highest serum DHEAS levels (odds ratio 1.59; 95% confidence interval 1.04-2.43; p < 0.05). Exclusion of men with high alcohol consumption did not affect these results substantially. Hepatic steatosis is associated with low serum testosterone and high serum DHEAS levels. These associations are independent of alcohol consumption.

Combinations of carbohydrate-deficient transferrin, mean corpuscular erythrocyte volume, gamma-glutamyltransferase, homocysteine and folate increase the significance of biological markers in alcohol dependent patients

AIMS

The traditionally used biological markers for alcoholism include a wide range of sensitivity and specificity as single tests. This study focuses on the combination of established laboratory parameters with new meaningful biomarkers to advance the significance regarding alcohol dependence.

DESIGN

We analyzed blood samples from alcohol-dependent patients (n=177) compared with a control group (n=181). In the statistical calculation we included carbohydrate-deficient transferrin (CDT), mean corpuscular erythrocyte volume (MCV), gamma-glutamyltransferase (GGT), total plasma homocysteine, and folate.

RESULTS

None of the examined biomarkers reached sensitivity above 90% while all markers showed a good specificity. Combinations of different markers led to a significant elevation in sensitivity. Best values for men were achieved by using a combination of MCV, CDT, GGT, homocysteine and folate in different weightings (sensitivity: 98.6%, specificity: 86.4%). For women, similar results were yielded by combining MCV and CDT (sensitivity: 94.1%, specificity: 96%). The addition of homocysteine and folate in different weightings did not result in further enhancement.

CONCLUSIONS

Gender-specific clusters including MCV, CDT, GGT, homocysteine and folate led to an increase in sensitivity compared to single laboratory markers. This is a reliable help to identify patients with regular heavy drinking in clinical practice which might prevent further complications.

DOVER and QUVER-new marker combinations to detect and monitor at-risk drinking

BACKGROUND

At-risk drinking is a common medical problem. "Objective" laboratory tests are widely used, especially in situations where it might be favorable for the patient to dissimulate the existing alcohol problem. In this study, we report a new approach to combine the biological markers % carbohydrate-deficient transferrin (%CDT) and gamma-glutamyltransferase (gammaGT) to increase diagnostic properties to identify patients with at-risk drinking behavior.

METHODS

Fifty-eight general practitioners (GPs) participated in the study at 2 study sites in South-West Germany. Patients filled in a questionnaire that included the Alcohol Use Disorders Identification Test (AUDIT) and gave a blood sample. The GP recorded his assessment about the presence of an alcohol-related disorder in the patient. Screening results of 1 test center were used as a calculation sample. The results at the other site were used to cross-validate the study outcomes. The markers were combined by 2 methods. The first approach used the AUDIT (QUestionnaire VERified; QUVER), and the second was performed using the clinical judgment of the treating GP (DOctor VERified; DOVER). The formulas were calculated using linear and logistic regression models, respectively.

RESULTS

A total of 2,940 patients participated in the study, of whom 2,496 completed data sets that could be used for further analysis. In the receiver-operating characteristics (ROC) curves with the reference standard of an AUDIT> or =8, the area under the curve (AUC) of 78.8% for DOVER and 80.6% (QUVER) are in a higher range than the values for gamma-%CDT (75.4%) or gamma-GT (66.3%) and %CDT (74.3%) and suggest a clear superiority of the proposed marker combinations. Regarding the combinations DOVER and QUVER, the cross-validation results were almost identical, with 78.4/78.8% and 80.6/79.5%, respectively.

CONCLUSION

Our study is to date the largest practice-based trial that examines the value of the markers CDT and gamma-GT and their combinations for the screening of at-risk drinking in general practice under routine conditions. Our ROC analysis clearly demonstrated that the combination of the markers gamma-GT and %CDT under routine conditions with a behaviorally oriented reference standard leads to an improvement of diagnostic performance, more so than the use of single markers.

Carbohydrate-deficient transferrin (CDT) as a marker of alcohol abuse: a critical review of the literature 2001-2005

The diagnosis of alcohol abuse based on objective data is a necessary requirement in both clinical and forensic environments. Among the different biomarkers of chronic alcohol abuse, carbohydrate-deficient transferrin (CDT) is world wide recognized as the most reliable indicator. However, several problems about the real meaning of CDT and the reliability of its use for the diagnosis of alcohol abuses are still open, as reported by numerous research articles and reviews. The present article presents a critical review of the literature on CDT appeared in the period from 2001 to 2005 (included). The article is organized in the following sections: (1) introduction, (2) definition and structure of human serum CDT, (3) pathomechanisms of the ethanol-induced CDT increase, (4) preanalysis, (5) analysis, (6) data interpretation, (7) review papers, (8) conclusions. As many as 127 papers appeared in the international literature and retrieved by the search engines PubMed and Scopus are quoted.

Validity of carbohydrate-deficient transferrin (%CDT), gamma-glutamyltransferase (gamma-GT) and mean corpuscular erythrocyte volume (MCV) as biomarkers for chronic alcohol abuse: a study in patients with alcohol dependence and liver disorders of non-alcoholic and alcoholic origin

AIM

To test the clinical performance of carbohydrate-deficient transferrin (%CDT), gamma-glutamyltransferase (gamma-GT) and mean corpuscular erythrocyte volume (MCV) as biomarkers for alcoholism with a special focus on patients suffering from liver diseases.

DESIGN

Well-characterized collectives of alcohol-dependent patients with current consumption (ALC patients, n = 101), and relevant control groups (115 social drinkers, 46 patients with unspecifically increased gamma-GT, 51 hepatitis patients and 20/31 patients with non-alcohol/alcohol-dependent liver cirrhosis) were included into the study. The Positive Alcohol Use Disorders Test (AUDIT) score, International Classification of Diseases version 10 (ICD-10)/Diagnostic and Statistical Manual version IV (DSM-IV) criteria and blood drawn within 4 days of last drinking were inclusion criteria for subjects with regular heavy drinking. %CDT was determined using an automated assay which recently had been completely modified.

FINDINGS

Median AUDIT scores of patients without/with regular heavy drinking were 1-3/27. The following medians/95th percentiles were obtained for %CDT: social drinkers 2.2/3.0, patients with unspecifically increased gamma-GT 2.1/3.0, hepatitis 2.0/4.4, non-alcohol-dependent liver cirrhosis 2.4/4.8, alcohol-dependent liver cirrhosis 3.0/5.9, ALC patients 3.9/14.9. Differences between patients without and with alcohol abuse were highly significant (P < 0.001). No differences in CDT values were found between males and females. There was no correlation between %CDT values, gamma-GT, MCV and the amount of alcohol consumed in ALC patients; 3.0%CDT (95th percentile social drinkers) is proposed as cut-off for the test used (Tina-quant %CDT 2nd-generation). At this cut-off, the sensitivity for ALC patients was 73.3%, whereas gamma-GT/MCV had a sensitivity of 71.3%/64.4%. Multivariate analysis performed at 95% specificity resulted in an improvement of the sensitivity by combining %CDT with gamma-GT (83.2%). A further enhancement of the sensitivity to 88.1% was obtained by combination of %CDT, gamma-GT and MCV. The diagnostic specificity of %CDT calculated at the cut-off of 3% was 93.5% in patients with unspecifically increased gamma-GT, 88.2% in hepatitis patients and 70.0% in patients with non-alcohol-dependent liver cirrhosis. %CDT was more specific in these patient collectives than MCV, and especially more than gamma-GT (specificity in hepatitis 52.9%, and 35.0% in non-alcohol-dependent liver cirrhosis).

CONCLUSION

%CDT is of high diagnostic value to support diagnosis of alcohol-use disorders. The specificity of this marker in patient groups with liver disorders is superior to the biomarkers gamma-GT and MCV.