Carbohydrate-deficient transferrin and alcohol use in medical examiner cases

Post-mortem stability and redistribution of carbohydrate-deficient transferrin (CDT)

Post-mortem diagnosis of chronic alcohol abuse is a challenge for forensic experts due to the lack of pathognomonic morphological findings and often also inadequate background information. Objective methods demonstrating chronic excessive alcohol consumption would therefore be a useful tool for forensic pathologists. In clinical practice, several markers of chronic alcohol abuse have recently been introduced, among which carbohydrate-deficient transferrin (CDT) is the most accepted, but the use of these markers in autopsy has not yet been established. We examined post-mortem stability and possible post-mortem redistribution of CDT and compared two analytical methods, capillary zone electrophoresis and high-performance liquid chromatography. According to our results, CDT remains stable for an appreciable time after death. The results further indicate that CDT is not subject to major post-mortem redistribution.

Biochemical markers of alcoholism

Alcohol and alcohol-related diseases have become a major cause of death in Western countries. The most sensitive and specific of the commonly used biomarkers of alcohol intake are carbohydrate-deficient transferrin (CDT), and the combination of gamma-glutamyltransferase (GGT) and CDT. Other widely used laboratory markers are GGT, mean corpuscular volume of erythrocytes and the ratio of aspartate aminotransferase to alanine aminotransferase. Blood ethanol levels reveal recent alcohol use. However, more specific and sensitive biomarkers to improve the detection of excessive alcohol use at an early stage are needed. New biomarkers, not yet used in routine clinical work, include phosphatidylethanol, fatty acid ethyl esters, ethyl glucuronide, sialic acid, and acetaldehyde adducts.

The Bayesian Alcoholism Test had better diagnostic properties for confirming diagnosis of hazardous and harmful alcohol use

OBJECTIVE

Conventional tests for alcoholism fail to confirm hazardous and harmful alcohol use (HHAU) accurately and objectively. We validated a Bayesian Alcoholism Test (BAT) for confirming the diagnosis of HHAU.

STUDY DESIGN AND SETTING

BAT is based on studies on the prevalence of HHAU and other diseases causing similar abnormalities, and on conditional probabilities of these disorders and associated biochemical markers and clinical signs. BAT was compared to carbohydrate-deficient transferrin (CDT) and gamma-glutamyltransferase (GGT) in treatment-seeking alcoholics, non-treatment-seeking heavy drinkers, and controls. Main outcome measures were test sensitivity and specificity, likelihood ratios, and receiver-operating characteristic (ROC) curves.

RESULTS

Comparing alcoholics and controls, sensitivity of BAT (94%) was significantly higher than CDT (63%) and GGT (73%). The area under the ROC curve for BAT (.989) was significantly higher than the area under the curve for CDT (.909) and area under the curve for GGT (.902). Using pooled data of all 182 subjects included in the study, the amount of drinking had a significant better correlation coefficient with BAT (.795) than with CDT (.657), and GGT (.604).

CONCLUSION

BAT has better diagnostic properties than CDT and GGT for confirming HHAU.

Detection of alcohol consumption in suicides

Screening instruments for detection of alcohol consumption, abuse, and dependence for use in psychological autopsy studies with case control design are not validated. Therefore, interrater and test-retest reliability of the Luebeck Alcohol Dependence and Abuse Screening Test (LAST) and the usability of this test for the psychological autopsy method were investigated. Alcohol consumption was evaluated by a semi-structured interview including the Structured Clinical Interview for DSM-IV Axis I (SCID-I) and the LAST in 163 completed suicides (mean age 49.6 +/- 19.3 years; 64.4% men) and by personal interview in 396 population-based controls (mean age 51.6 +/- 17.0 years; 55.8% men). Of the controls, 35 were additionally assessed by interviewing informants; these results were compared with those generated by personal interview. Comparison of LAST scores by personal and informant's interview of controls generated a Spearman correlation coefficient of 0.74 (P < 0.0001). The LAST (7 item-version, cut-off of 2) revealed high sensitivity and specificity for alcohol abuse and dependence, in both controls and suicides. LAST scores were significantly associated with high, frequent, and hazardous alcohol consumption (P < 0.001) in suicides. Our findings provide support for reliability and validity of identifying individuals with alcohol dependence and abuse obtained through the best-estimate method using the LAST. This 7-item questionnaire can be recommended as a useful tool for the psychological autopsy procedure in postmortem research.

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.

Biological markers for suicidal behavior in alcohol dependence

Alcohol-dependent populations have a high lifetime suicide rate (between 7 and 15%, relative risk = 7), and alcoholism is one of the two psychiatric disorders most frequently found in suicidal cases (between 15 and 25%). Biological factors that would detect patients at risk could thus be of value. Carbohydrate-deficient transferrin, monoamine oxidase B, soluble interleukin-2 receptor and cholesterol have been proposed as markers of suicidal risk in alcohol-dependent patients, although nonspecific and with low predictive value. On the other hand, there is large and convergent data stressing the importance of serotonin dysregulation as increasing the risk for aggressive behaviour toward the self, although it is not clear whether serotonin is involved through the altered behavior inhibition system, enhancement of anxiety and depression, or association with specific subtypes of alcohol-dependence, such as early-onset type II alcoholism. Considering the complex but significant impact of alcohol on serotonin metabolism and turnover, it is likely that serotonin mediates a large part of the proneness of ethanol to commit impulsive-aggressive behavior.

A review of postmortem alcohol detection as a diagnostic test for substance abuse disorders in suicides

To assess the role of toxicologic detection of alcohol to diagnose substance abuse disorders in suicides, the author reviewed suicide studies with both comprehensive toxicologic and diagnostic data. The sensitivity of alcohol detection to diagnose alcohol and substance abuse disorders in suicides was low in all studies (range, 39%-42%), and the specificity was 80%-95%. A higher cutoff level for alcohol did not increase diagnostic performance. The author concludes that toxicologic detection of alcohol is not a reliable indicator of alcohol and substance abuse disorders in suicides because of the high rate of false-negatives. Most of the suicides with positive alcohol detection seem to suffer from chronic substance abuse problems. The role of intoxication is difficult to assess because of methodologic problems.