Is carbohydrate deficient transferrin a useful marker of harmful alcohol intake among surgical patients?

Comparison of self-reports and biological measures for alcohol, tobacco, and illicit drugs consumption in psychiatric inpatients

Background

Asking psychiatric in-patients about their drug consumption is unlikely to yield reliable results, particularly where alcohol and illicit drug use is involved. The main aim of this study was to compare spontaneous self-reports of drug use in hospitalized psychiatric patients to biological measures of same. A secondary aim was to determine which personal factors were associated with the use of tobacco, alcohol, and illicit drugs as indicated by these biological measures.

Methods

The consumption of substances was investigated using biological measures (urine cotinine, cannabis, opiates, cocaine, amphetamines and barbiturates; blood carbohydrate-deficient transferrin [CDT] and gamma-glutamyl transferase [GGT]) in 486 consecutively admitted psychiatric patients, one day following their hospitalization. Patients’ self-reports of alcohol, tobacco and illicit drugs consumption were recorded. Socio-professional and familial data were also recorded.

Results

The results show a low correlation between biological measures and self-reported consumption of alcohol and illicit drugs. Fifty-two percent of the patients under-reported their consumption of illicit drugs (kappa = .47). Patients with schizophrenia and personality disorders were more likely to disclose their illicit drug consumption relative to patients suffering from mood disorders and alcohol dependence. Fifty-six percent of patients underreported alcohol use, as evaluated by CDT (kappa = .2), and 37% underreported when using the CDT + GGT measure as an indicator. Smoking appeared to be reported adequately. In the study we observed a strong negative correlation between cannabis use and age, a strong correlation between tobacco and cannabis use, and correlations between tobacco, cannabis and alcohol consumption.

Conclusion

This study is the first to compare self-reports and biological measures of alcohol, tobacco and illicit drug uses in a large sample of inpatients suffering from various categories of psychiatric illnesses, allowing for cross-diagnosis comparisons.

Alcohol biomarkers in patients admitted for trauma

BACKGROUND

To assess the value of blood alcohol levels (BAL) and carbohydrate-deficient transferrin (CDT) in trauma patients.

METHODS

A prospective study was conducted among 213 patients admitted to a university hospital after trauma. Outcomes of interest included the development of alcohol withdrawal, infections, respiratory problems, cardiac events, thromboembolism, and length of stay.

RESULTS

The majority (78%) of the trauma patients in the study was males over the age of 18. Seventy-five percent were reported drinking an alcohol-containing beverage in the previous 30 days, 34% had > or =5 heavy drinking days, and 18.7% met current DSM-IV criteria for alcohol abuse and 13.1% current criteria for dependence. Twenty-two percent (n = 48) had a positive BAL and 14% (n = 30) a CDT level >2.5%. Twelve percent (n = 27) of the sample developed alcohol withdrawal and 55% (n = 113) had one or more adverse health events during their hospitalization. The development of alcohol withdrawal was associated with an admission CDT >2.5% (chi(2): 4.77, p < 0.029) and/or a positive BAL (chi(2): 54.01, p < 0.001). The alcohol biomarkers identified 13 male and 3 female high-risk patients (7.4% of the total sample) who denied excessive alcohol use, and who would have been missed if these markers were not used. A composite morbidity trauma score composed of 25 adverse health events was associated with a positive BAL (p < 0.022).

CONCLUSION

The study provides additional empirical evidence that supports the use of BAL in all patients admitted for trauma. The usefulness of CDT in trauma patients remains unclear and will require larger samples in more critically ill patients.

Cost-Benefit Analysis of a New Alcohol Biomarker, Carbohydrate Deficient Transferrin, in a Chronic Illness Primary Care Sample

BACKGROUND

Carbohydrate Deficient Transferrin (CDT) is a new alcohol biomarker recently approved by the Food and Drug Administration for alcohol screening. Limited information is available on the economic benefits of alcohol biomarkers. Our objective was to conduct a cost-benefit analysis (CBA) of the CDT test in a primary care sample of patients being treated for diabetes and hypertension.

METHODS

A decision tree was created using data from national surveys, published literature, and two brief intervention trials conducted in primary care settings. The decision tree was used to estimate the costs and benefits of CDT under different scenarios.

RESULTS

For the base case, utilizing CDT in addition to patient self-report resulted in an increase from 28 to 53 problem drinking cases identified out of 70 cases screened. With increased detection and subsequent intervention, the average medical and legal costs were far lower in the CDT arm of the study. When these avoided costs were incorporated into the model, an overall savings of $212.30 per patient was realized with CDT testing. Monte Carlo analysis also indicated a trend toward cost savings, with a mean cost savings of approximately $353 and a range of $1,619 in savings to $450 in costs for 1,000 simulations of the decision tree model.

CONCLUSION

This CBA suggests that the addition of routine CDT screening to patient self-report may provide positive net economic benefits in primary care settings.

A review of genetic, biological, pharmacological, and clinical factors that affect carbohydrate-deficient transferrin levels

BACKGROUND

Carbohydrate-deficient transferrin (CDT) is an alcohol biomarker recently approved by the U.S. Food and Drug Administration. This test is increasingly being used to detect and monitor alcohol use in a variety of health care, legal, and industrial settings. The goal of this study is to review the genetic, biological, pharmacological, and clinical factors that may affect CDT levels.

METHODS

A review of the literature identified 95 research articles that met the authors' criteria and reported potential interactions of a variety of factors on percent and total CDT levels. The review established 12 categories of variables that may affect CDT levels. These categories include (1) alcohol use, (2) genetic factors, (3) race, (4) gender, (5) age, (6) liver disease, (7) iron levels, (8) tobacco use, (9) medication such as estrogen and anticonvulsants, (10) metabolic factors such as body mass index and total body water, (11) chronic medical conditions such as rheumatoid arthritis, and (12) surgical patients.

RESULTS

There is evidence that %CDT levels are affected by alcohol use, end-stage liver disease, and genetic variants. In addition to these three factors, total CDT levels (CDTect) are also affected by factors that raise transferrin levels such as iron deficiency, chronic illnesses, and menopausal status. Other potential factors such as tobacco and age appear to be confounded by alcohol use. The roles of female gender, low body mass index, chronic inflammatory diseases, and medication on CDT levels require further study. False negatives are associated with female gender, episodic lower level alcohol use, and acute trauma with blood loss.

CONCLUSIONS

This review suggests that a number of factors are associated with false-positive CDTect and %CDT levels. CDT offers great promise to assist physicians in the care of patients to detect and monitor heavy alcohol use.

Carbohydrate-deficient transferrin (CDT)--a biomarker for long-term alcohol consumption

Carbohydrate-deficient transferrin (CDT) is a biomarker for chronic alcohol intake of more than 60 g ethanol/d. It has been reported to be superior to conventional markers like gamma-glutamyltransferase (GGT) and mean corpuscular volume MCV). This review covers theoretical and analytical aspects, with data from controlled drinking experiments and from different population subgroups such as subjects with different liver diseases or different drinking patterns. CDT determinations are particularly indicated in (1) cases of chronic alcohol consumption and relapses after withdrawal, (2) license reapplication after driving under alcohol influence, (3) differentiating patients with enzyme-inducing medication from those with alcohol abuse, 4) congenital disorders of glycosylation such as carbohydrate-deficient glycoprotein syndrome Ia (CDGS Ia), and (5) patients treated for galactosemia. The main advantage of CDT is its high specificity, as evidenced in combination with increased alcohol consumption. CDT values are not markedly influenced by medication except in immunosuppressed patients, who may show low CDT values. In general, CDT values appear less elevated after alcohol intake in women. The main disadvantage is the relatively low sensitivity. Hence, this parameter is not suitable for screening for subjects with alcohol abuse in the general population. As CDT, GGT, and MCV are connected with chronic alcohol consumption by different pathophysiological mechanisms, a combination of these parameters will further improve the diagnostic value.

Biological markers in alcoholism

Alcohol biomarkers include tests indicative of acute or chronic alcohol consumption (state markers), and markers of a genetic predisposition to develop alcohol dependence after chronic exposure (trait markers). While a comprehensive trait marker for alcohol dependence has not been identified, a number of successful state markers for monitoring drinking status are used clinically. These tests provide direct or indirect ways to estimate the amounts of alcohol consumed and the duration of ingestion, and to detect any harmful effects on body functions resulting from long-term misuse. The most obvious method to prove recent drinking is by demonstrating the presence of ethanol in body fluids or breath, but, because ethanol is cleared fairly rapidly from the body, this method is limited to detect only very recent drinking. Measurement of urinary 5-hydroxytryptophol or ethyl glucuronide provide more sensitive methods to disclose recent drinking, because their washout constants are much longer than for ethanol. The liver functions test (GGT, AST and ALT in serum) and the mean corpuscular volume of erythrocytes (MCV) are among the standard diagnostic tools used to identify chronic alcohol exposure. The main disadvantage with these measures is that they have low sensitivity for recent excessive intake, and that raised levels may result from several causes besides heavy drinking, implying a low specificity for alcohol. Carbohydrate-deficient transferrin (CDT), which refers to changes in the carbohydrate composition of serum transferrin, is a more specific marker for identifying excessive alcohol consumption and monitoring abstinence during outpatient treatment. The alcohol biomarkers improves knowledge of drinking patterns in both individuals and populations, and they are also valuable tools for the objective evaluation of treatment efforts. Alcohol markers have, for example, found uses in early identification of at-risk and harmful drinking, and they help to monitor abstinence and relapse in response to outpatient treatment.

Use of biomarkers for alcohol use disorders in clinical practice

BACKGROUND

Biomedical markers may provide additive objective information in screening and confirmation of acute or recent consumption, intoxication, relapse, heavy drinking, hazardous/harmful use/abuse and dependence and alcohol use related organ dysfunction (alcohol use-related disorders: AUDs).

AIMS

To review the use of biomarkers in clinical practice to detect AUDs.

FINDINGS

About one-fifth of the patients seen in clinical practice have AUDs, which offer a variety of treatment options if diagnosed. The diagnosis of AUDs relies on clinical and alcohol-related history, physical examination, questionnaires and laboratory values. No clinical available laboratory test [e.g. for acute abuse: alcohol in blood or breath; for chronic alcohol abuse: gamma-glutamyl transferase (GGT), mean corpuscular volume (MCV), carbohydrate-deficient transferrin (CDT)] is reliable enough on its own to support a diagnosis of alcohol dependence, harmful use or abuse. Sensitivities, specificities and the predictive values may vary considerably according to patient and control group characteristics (e.g. gender, age or related comorbidity). In patient groups with limited cooperation markers may be helpful when considering treatment options.

CONCLUSIONS

More research is needed to determine the value of markers (single or combined, with questionnaires) in the context of clinical decision-making algorithms in defined settings and with defined dichotomous outcome variables.

Biochemical markers of alcohol use in pregnant women

OBJECTIVES

To describe the serious health consequences of alcohol (ethanol) use, especially as they relate to pregnancy and the development of fetal alcohol syndrome (FAS) and fetal alcohol effects (FAE). The classic markers of alcohol exposure, including blood/breath alcohol, gamma-glutamyl transferase (gammaGT), mean corpuscular volume (MCV), hemoglobin-associated acetaldehyde (HAA) and carbohydrate deficient transferrin (CDT), are valuable and their methods of analysis are reviewed.

CONCLUSIONS

Since both FAS and FAE represent two of the leading preventable causes of mental retardation and birth defects, identification of alcohol use early in pregnancy is important to avoid adverse fetal outcomes. Unfortunately, the diagnosis of FAS and FAE is usually made after birth, when alcohol damage has become irreversible and permanent. The clinical laboratory can help prevent this damage and make a valuable contribution in assessing prenatal alcohol use. The clinical utility of blood/breath alcohol, gammaGT, MCV, HAA and CDT in alcohol use identification, especially in pregnancy, is substantial. Although none of the markers singularly has adequate sensitivity and specificity for screening, their diagnostic utility increases when measured as a panel. This is especially true in detecting alcohol use in pregnancy where the presence of several positive markers was correlated with the presence of alcohol-related fetal effects.