Co-morbidity of alcohol dependence and select affective and anxiety disorders among individuals of East Indian and African ancestry in Trinidad and Tobago.

The present study sought to determine whether an association exists between alcohol dependence and select affective and anxiety disorders in patients presenting at substance abuse centres in Trinidad and Tobago (TT). The participants in this study were 143 alcohol dependents, of either East Indian ancestry (Indo-TT) or African ancestry (Afro-TT) and 109 controls matched by age, gender and ethnicity. A structured interview was used to gather information on demographics, psychiatric diagnoses and personal drinking and drug use. A blood sample was obtained and used to genotype for the presence of ADH and ALDH1 polymorphisms and serum levels of hepatic enzymes. Forty-one per cent of Indo-TT and 37% of Afro-TT with alcohol dependence had co-morbid major depressive disorders independent of alcohol and/or drug use. Thirty-nine per cent of Indo-TT and 37% of Afro-TT with alcohol dependence had co-morbid major depression induced by alcohol or drug use. The severity of depression was significantly associated with severity of alcohol dependence. Neither major depression nor the severity of depressive episodes was associated with values of any liver function test or the presence of ALDH1*2 or ADH1C*2 alleles. However in participants of African descent elevated alanine transaminase ALT was associated (p = 0.038) with not having substance-induced major depression. Co-morbidity of major depressive disorder with alcohol dependence is common in the two major ethnic groups in Trinidad and Tobago and appears to be as likely the consequence of drinking and/or drug use, as the cause. Clinicians should solicit a history of depression from patients with alcohol dependence.

Variations in alcohol-metabolizing enzymes in people of East Indian and African descent from Trinidad and Tobago.

The population of Trinidad and Tobago is composed mainly of people of East Indian (Indo-Trinidadians) and African (Afro-Trinidadians) ancestry. Differences in alcoholism rates exist between these two ethnic groups, and researchers have investigated whether these differences can be explained in part by variations in the genes encoding the alcohol-metabolizing enzymes alcohol dehydrogenase (ADH) 1B and 1C, and aldehyde dehydrogenase (ALDH) 1 and 2. Studies have demonstrated that a certain variant of the gene encoding ADH1B (ADH1B*3) is associated with a reduced risk of alcoholism in Afro-Trinidadians, as is a variant of the gene encoding ADH1C (i.e., ADH1C*1) in Indo-Trinidadians. An ALDH2 variant shown to have protective effects primarily in East Asians was not found in either Trinidadian ethnic group. However, a variant in the gene encoding cytosolic ALDH1A (i.e. ALDH1A1*1/*2) was found to be associated with an increase in alcohol dependence in Indo-Trinidadians.

The therapeutic transnosological use of psychotropic drugs.

The current clinical use of psychotropic drugs is transnosologically oriented. This is facilitated by the current classification of mental disorders (International Classification of Diseases, 10th Revision [ICD-10]) and is perhaps justified if depression and psychosis (taken here as examples) are considered as being complex syndromes with heterogeneous etiologies, but common pathogenesis, more than specific entities. However, this approach does not identify possible differences between specific psychiatric entities, which could in turn mask differences in therapeutic responses and, therefore, therapeutic outcome. This is compounded by the current disharmony between the nosological classification of diseases, drug development, clinical research, and therapeutic uses of psychotropic drugs. Functional pharmacology targeting abnormal behavioral traits could represent an avenue for future research and treatment.