A Prospective Comparison of Bipolar I and II Subjects With and Without Comorbid Alcohol Dependence From the COGA Dataset.

Objective: Comorbidity of alcohol use disorders in bipolar subjects is high as indicated by epidemiological and clinical studies. Though a more severe course of bipolar disorder in subjects with comorbid alcohol dependence has been reported, fewer studies considered the longitudinal course of alcohol dependence in bipolar subjects and the prospective course of comorbid bipolar II subjects. Beside baseline analysis, longitudinal data of the COGA (Collaborative Study on Genetics in Alcoholism) were used to evaluate the course of bipolar I and II disordered subjects with and without comorbid alcohol dependence over more than 5 years of follow-up. Methods: Characteristics of bipolar disorder, alcohol dependence and comorbid psychiatric disorders were assessed using semi-structured interviews (SSAGA) at baseline and at a 5-year follow-up. Two hundred twenty-eight bipolar I and II patients were subdivided into groups with and without comorbid alcohol dependence. Results: Of the 152 bipolar I and 76 bipolar II patients, 172 (75, 4%) had a comorbid diagnosis of alcohol dependence. Bipolar I patients with alcohol dependence, in particular women, had a more severe course of bipolar disorder, worse social functioning and more suicidal behavior than all other groups of subjects during the 5-year follow-up. In contrast, alcohol dependence improved significantly in both comorbid bipolar I and II individuals during this time. Conclusions: A 5-year prospective evaluation of bipolar patients with and without alcohol dependence confirmed previous investigations suggesting a more severe course of bipolar disorder in comorbid bipolar I individuals, whereas bipolar II individuals were less severely impaired by comorbid alcohol use disorder. While severity of alcohol dependence improved during this time in comorbid alcohol-dependent bipolar I patients, the unfavorable outcome for these individuals might be due to the higher comorbidity with personality and other substance use disorders which, together with alcohol dependence, eventually lead to poorer symptomatic and functional clinical outcomes.

Genome-wide association study identifies a novel locus for cannabis dependence.

Despite moderate heritability, only one study has identified genome-wide significant loci for cannabis-related phenotypes. We conducted meta-analyses of genome-wide association study data on 2080 cannabis-dependent cases and 6435 cannabis-exposed controls of European descent. A cluster of correlated single-nucleotide polymorphisms (SNPs) in a novel region on chromosome 10 was genome-wide significant (lowest P=1.3E-8). Among the SNPs, rs1409568 showed enrichment for H3K4me1 and H3K427ac marks, suggesting its role as an enhancer in addiction-relevant brain regions, such as the dorsolateral prefrontal cortex and the angular and cingulate gyri. This SNP is also predicted to modify binding scores for several transcription factors. We found modest evidence for replication for rs1409568 in an independent cohort of African American (896 cases and 1591 controls; P=0.03) but not European American (EA; 781 cases and 1905 controls) participants. The combined meta-analysis (3757 cases and 9931 controls) indicated trend-level significance for rs1409568 (P=2.85E-7). No genome-wide significant loci emerged for cannabis dependence criterion count (n=8050). There was also evidence that the minor allele of rs1409568 was associated with a 2.1% increase in right hippocampal volume in an independent sample of 430 EA college students (fwe-P=0.008). The identification and characterization of genome-wide significant loci for cannabis dependence is among the first steps toward understanding the biological contributions to the etiology of this psychiatric disorder, which appears to be rising in some developed nations.

An endophenotype approach to the genetics of alcohol dependence: a genome wide association study of fast beta EEG in families of African ancestry.

Fast beta (20-28 Hz) electroencephalogram (EEG) oscillatory activity may be a useful endophenotype for studying the genetics of disorders characterized by neural hyperexcitability, including substance use disorders (SUDs). However, the genetic underpinnings of fast beta EEG have not previously been studied in a population of African-American ancestry (AA). In a sample of 2382 AA individuals from 482 families drawn from the Collaborative Study on the Genetics of Alcoholism (COGA), we performed a genome-wide association study (GWAS) on resting-state fast beta EEG power. To further characterize our genetic findings, we examined the functional and clinical/behavioral significance of GWAS variants. Ten correlated single-nucleotide polymorphisms (SNPs) (r2>0.9) located in an intergenic region on chromosome 3q26 were associated with fast beta EEG power at P<5 × 10-8. The most significantly associated SNP, rs11720469 (ß: -0.124; P<4.5 × 10-9), is also an expression quantitative trait locus for BCHE (butyrylcholinesterase), expressed in thalamus tissue. Four of the genome-wide SNPs were also associated with Diagnostic and Statistical Manual of Mental Disorders Alcohol Dependence in COGA AA families, and two (rs13093097, rs7428372) were replicated in an independent AA sample (Gelernter et al.). Analyses in the AA adolescent/young adult (offspring from COGA families) subsample indicated association of rs11720469 with heavy episodic drinking (frequency of consuming 5+ drinks within 24 h). Converging findings presented in this study provide support for the role of genetic variants within 3q26 in neural and behavioral disinhibition. These novel genetic findings highlight the importance of including AA populations in genetics research on SUDs and the utility of the endophenotype approach in enhancing our understanding of mechanisms underlying addiction susceptibility.

Genome-wide polygenic scores for age at onset of alcohol dependence and association with alcohol-related measures.

Age at onset of alcohol dependence (AO-AD) is a defining feature of multiple drinking typologies. AO-AD is heritable and likely shares genetic liability with other aspects of alcohol consumption. We examine whether polygenic variation in AO-AD, based on a genome-wide association study (GWAS), was associated with AO-AD and other aspects of alcohol consumption in two independent samples. Genetic risk scores (GRS) were created based on AO-AD GWAS results from a discovery sample of 1788 regular drinkers from extended pedigrees from the Collaborative Study of the Genetics of Alcoholism (COGA). GRS were used to predict AO-AD, AD and Alcohol dependence symptom count (AD-SX), age at onset of intoxication (AO-I), as well as maxdrinks in regular drinking participants from two independent samples-the Study of Addictions: Genes and Environment (SAGE; n=2336) and an Australian sample (OZ-ALC; n=5816). GRS for AO-AD from COGA explained a modest but significant proportion of the variance in all alcohol-related phenotypes in SAGE. Despite including effect sizes associated with large numbers of single nucleotide polymorphisms (SNPs; >110 000), GRS explained, at most, 0.7% of the variance in these alcohol measures in this independent sample. In OZ-ALC, significant but even more modest associations were noted with variance estimates ranging from 0.03 to 0.16%. In conclusion, there is modest evidence that genetic variation in AO-AD is associated with liability to other aspects of alcohol involvement.

Evidence of CNIH3 involvement in opioid dependence.

Opioid dependence, a severe addictive disorder and major societal problem, has been demonstrated to be moderately heritable. We conducted a genome-wide association study in Comorbidity and Trauma Study data comparing opioid-dependent daily injectors (N=1167) with opioid misusers who never progressed to daily injection (N=161). The strongest associations, observed for CNIH3 single-nucleotide polymorphisms (SNPs), were confirmed in two independent samples, the Yale-Penn genetic studies of opioid, cocaine and alcohol dependence and the Study of Addiction: Genetics and Environment, which both contain non-dependent opioid misusers and opioid-dependent individuals. Meta-analyses found five genome-wide significant CNIH3 SNPs. The A allele of rs10799590, the most highly associated SNP, was robustly protective (P=4.30E-9; odds ratio 0.64 (95% confidence interval 0.55-0.74)). Epigenetic annotation predicts that this SNP is functional in fetal brain. Neuroimaging data from the Duke Neurogenetics Study (N=312) provide evidence of this SNP's in vivo functionality; rs10799590 A allele carriers displayed significantly greater right amygdala habituation to threat-related facial expressions, a phenotype associated with resilience to psychopathology. Computational genetic analyses of physical dependence on morphine across 23 mouse strains yielded significant correlations for haplotypes in CNIH3 and functionally related genes. These convergent findings support CNIH3 involvement in the pathophysiology of opioid dependence, complementing prior studies implicating the α-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid (AMPA) glutamate system.

Genome-wide association data suggest ABCB1 and immune-related gene sets may be involved in adult antisocial behavior.

Adult antisocial behavior (AAB) is moderately heritable, relatively common and has adverse consequences for individuals and society. We examined the molecular genetic basis of AAB in 1379 participants from a case-control study in which the cases met criteria for alcohol dependence. We also examined whether genes of interest were expressed in human brain. AAB was measured using a count of the number of Antisocial Personality Disorder criteria endorsed under criterion A from the Diagnostic and Statistical Manual of Mental Disorders, 4th Edition (DSM-IV). Participants were genotyped on the Illumina Human 1M BeadChip. In total, all single-nucleotide polymorphisms (SNPs) accounted for 25% of the variance in AAB, although this estimate was not significant (P=0.09). Enrichment tests indicated that more significantly associated genes were over-represented in seven gene sets, and most were immune related. Our most highly associated SNP (rs4728702, P=5.77 × 10(-7)) was located in the protein-coding adenosine triphosphate-binding cassette, sub-family B (MDR/TAP), member 1 (ABCB1). In a gene-based test, ABCB1 was genome-wide significant (q=0.03). Expression analyses indicated that ABCB1 was robustly expressed in the brain. ABCB1 has been implicated in substance use, and in post hoc tests we found that variation in ABCB1 was associated with DSM-IV alcohol and cocaine dependence criterion counts. These results suggest that ABCB1 may confer risk across externalizing behaviors, and are consistent with previous suggestions that immune pathways are associated with externalizing behaviors. The results should be tempered by the fact that we did not replicate the associations for ABCB1 or the gene sets in a less-affected independent sample.

Common biological networks underlie genetic risk for alcoholism in African- and European-American populations.

Alcohol dependence (AD) is a heritable substance addiction with adverse physical and psychological consequences, representing a major health and economic burden on societies worldwide. Genes thus far implicated via linkage, candidate gene and genome-wide association studies (GWAS) account for only a small fraction of its overall risk, with effects varying across ethnic groups. Here we investigate the genetic architecture of alcoholism and report on the extent to which common, genome-wide SNPs collectively account for risk of AD in two US populations, African-Americans (AAs) and European-Americans (EAs). Analyzing GWAS data for two independent case-control sample sets, we compute polymarker scores that are significantly associated with alcoholism (P = 1.64 × 10(-3) and 2.08 × 10(-4) for EAs and AAs, respectively), reflecting the small individual effects of thousands of variants derived from patterns of allelic architecture that are population specific. Simulations show that disease models based on rare and uncommon causal variants (MAF < 0.05) best fit the observed distribution of polymarker signals. When scoring bins were annotated for gene location and examined for constituent biological networks, gene enrichment is observed for several cellular processes and functions in both EA and AA populations, transcending their underlying allelic differences. Our results reveal key insights into the complex etiology of AD, raising the possibility of an important role for rare and uncommon variants, and identify polygenic mechanisms that encompass a spectrum of disease liability, with some, such as chloride transporters and glycine metabolism genes, displaying subtle, modifying effects that are likely to escape detection in most GWAS designs.

A genome-wide association study of alcohol-dependence symptom counts in extended pedigrees identifies C15orf53.

Several studies have identified genes associated with alcohol-use disorders (AUDs), but the variation in each of these genes explains only a small portion of the genetic vulnerability. The goal of the present study was to perform a genome-wide association study (GWAS) in extended families from the Collaborative Study on the Genetics of Alcoholism to identify novel genes affecting risk for alcohol dependence (AD). To maximize the power of the extended family design, we used a quantitative endophenotype, measured in all individuals: number of alcohol-dependence symptoms endorsed (symptom count (SC)). Secondary analyses were performed to determine if the single nucleotide polymorphisms (SNPs) associated with SC were also associated with the dichotomous phenotype, DSM-IV AD. This family-based GWAS identified SNPs in C15orf53 that are strongly associated with DSM-IV alcohol-dependence symptom counts (P=4.5 × 10(-8), inflation-corrected P=9.4 × 10(-7)). Results with DSM-IV AD in the regions of interest support our findings with SC, although the associations were less significant. Attempted replications of the most promising association results were conducted in two independent samples: nonoverlapping subjects from the Study of Addiction: Genes and Environment (SAGE) and the Australian Twin Family Study of AUDs (OZALC). Nominal association of C15orf53 with SC was observed in SAGE. The variant that showed strongest association with SC, rs12912251 and its highly correlated variants (D'=1, r(2) 0.95), have previously been associated with risk for bipolar disorder.

Family-based genome-wide association study of frontal θ oscillations identifies potassium channel gene KCNJ6.

Event-related oscillations (EROs) represent highly heritable neuroelectric correlates of cognitive processes that manifest deficits in alcoholics and in offspring at high risk to develop alcoholism. Theta ERO to targets in the visual oddball task has been shown to be an endophenotype for alcoholism. A family-based genome-wide association study was performed for the frontal theta ERO phenotype using 634 583 autosomal single nucleotide polymorphisms (SNPs) genotyped in 1560 family members from 117 families densely affected by alcohol use disorders, recruited in the Collaborative Study on the Genetics of Alcoholism. Genome-wide significant association was found with several SNPs on chromosome 21 in KCNJ6 (a potassium inward rectifier channel; KIR3.2/GIRK2), with the most significant SNP at P = 4.7 × 10(-10)). The same SNPs were also associated with EROs from central and parietal electrodes, but with less significance, suggesting that the association is frontally focused. One imputed synonymous SNP in exon four, highly correlated with our top three SNPs, was significantly associated with the frontal theta ERO phenotype. These results suggest KCNJ6 or its product GIRK2 account for some of the variations in frontal theta band oscillations. GIRK2 receptor activation contributes to slow inhibitory postsynaptic potentials that modulate neuronal excitability, and therefore influence neuronal networks.

ADH1B is associated with alcohol dependence and alcohol consumption in populations of European and African ancestry.

A coding variant in alcohol dehydrogenase 1B (ADH1B) (rs1229984) that leads to the replacement of Arg48 with His48 is common in Asian populations and reduces their risk for alcoholism, but because of very low allele frequencies the effects in European or African populations have been difficult to detect. We genotyped and analyzed this variant in three large European and African-American case-control studies in which alcohol dependence was defined by the Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition (DSM-IV) criteria, and demonstrated a strong protective effect of the His48 variant (odds ratio (OR) 0.34, 95% confidence interval (CI) 0.24, 0.48) on alcohol dependence, with genome-wide significance (6.6 × 10(-10)). The hypothesized mechanism of action involves an increased aversive reaction to alcohol; in keeping with this hypothesis, the same allele is strongly associated with a lower maximum number of drinks in a 24-hour period (lifetime), with P=3 × 10(-13). We also tested the effects of this allele on the development of alcoholism in adolescents and young adults, and demonstrated a significantly protective effect. This variant has the strongest effect on risk for alcohol dependence compared with any other tested variant in European populations.

Genome-wide association study of conduct disorder symptomatology.

Conduct disorder (CD) is one of the most prevalent childhood psychiatric conditions, and is associated with a number of serious concomitant and future problems. CD symptomatology is known to have a considerable genetic component, with heritability estimates in the range of 50%. Despite this, there is a relative paucity of studies aimed at identifying genes involved in the susceptibility to CD. In this study, we report results from a genome-wide association study of CD symptoms. CD symptoms were retrospectively reported by a psychiatric interview among a sample of cases and controls, in which cases met the criteria for alcohol dependence. Our primary phenotype was the natural log transformation of the number of CD symptoms that were endorsed, with data available for 3963 individuals who were genotyped on the Illumina Human 1M beadchip array. Secondary analyses are presented for case versus control status, in which caseness was established as endorsing three or more CD symptoms (N = 872 with CD and N = 3091 without CD). We find four markers that meet the criteria for genome-wide significance (P<5 × 10(-8)) with the CD symptom count, two of which are located in the gene C1QTNF7 (C1q and tumor necrosis factor-related protein 7). There were six additional SNPs in the gene that yielded converging evidence of association. These data provide the first evidence of a specific gene that is associated with CD symptomatology. None of the top signals resided in traditional candidate genes, underscoring the importance of a genome-wide approach for identifying novel variants involved in this serious childhood disorder.

Personality disorders in alcohol-dependent individuals: relationship with alcohol dependence severity.

The rate of axis II disorders in alcohol-dependent individuals is suggested to be high. The aim of this investigation is to assess the rate of DSM-IV axis II diagnoses in alcohol-dependent inpatients and their correlation with clinical characteristics of alcohol dependence (AD). 1,079 inpatients with DSM-IV AD from three inpatient addiction treatment centers ('qualified detoxification', open psychiatric university hospital wards) were included. Characteristics of AD were obtained using standardized structured interviews. Diagnoses of DSM-IV personality disorders (PDs) were generated with SCID-II-PQ and SCID-II interviews. Alcoholism severity was measured using the number of DSM-IV criteria endorsed and age at first drinking. Approximately 60% of the sample had at least one PD. However, rates of Axis II disorders differed significantly across centers. The most frequent PDs were obsessive-compulsive, borderline, narcissistic and paranoid PD. Diagnosis of any PD was related to a more severe clinical profile of AD. Regression analyses revealed that obsessive-compulsive PD was related to the number of DSM-IV criteria endorsed while antisocial PD was related to early age at first drinking. The majority of alcohol-dependent individuals had one or more comorbid axis II disorders. Univariate and multivariate analyses indicate that different PDs are related to age at first dinking and alcoholism severity.

Genetic variation in the CHRNA5 gene affects mRNA levels and is associated with risk for alcohol dependence.

Alcohol dependence frequently co-occurs with cigarette smoking, another common addictive behavior. Evidence from genetic studies demonstrates that alcohol dependence and smoking cluster in families and have shared genetic vulnerability. Recently a candidate gene study in nicotine dependent cases and nondependent smoking controls reported strong associations between a missense mutation (rs16969968) in exon 5 of the CHRNA5 gene and a variant in the 3'-UTR of the CHRNA3 gene and nicotine dependence. In this study we performed a comprehensive association analysis of the CHRNA5-CHRNA3-CHRNB4 gene cluster in the Collaborative Study on the Genetics of Alcoholism (COGA) families to investigate the role of genetic variants in risk for alcohol dependence. Using the family-based association test, we observed that a different group of polymorphisms, spanning CHRNA5-CHRNA3, demonstrate association with alcohol dependence defined by Diagnostic and Statistical Manual of Mental Disorders, 4th edn (DSM-IV) criteria. Using logistic regression we replicated this finding in an independent case-control series from the family study of cocaine dependence. These variants show low linkage disequilibrium with the SNPs previously reported to be associated with nicotine dependence and therefore represent an independent observation. Functional studies in human brain reveal that the variants associated with alcohol dependence are also associated with altered steady-state levels of CHRNA5 mRNA.

GABA-A2 receptor subunit gene (GABRA2) polymorphisms and risk for alcohol dependence.

Gamma-aminobutyric acid (GABA) A receptors are believed to mediate some of the physiological and behavioral actions of ethanol. Recent studies have suggested that genetic variants of the GABA-A receptor alpha2 subunit gene (GABRA2) are associated with alcohol dependence. The aim of this study is to confirm and extend the role of GABRA2 haplotypes in the liability to alcohol dependence. 291 (231 male) treatment-seeking alcohol-dependent individuals and 295 (153 male) control subjects were enrolled into the study. Characteristics of alcohol dependence were obtained using the SSAGA (semi-structured assessment of the genetics of alcoholism, German Version). Genotyping of 10 SNPs across the GABRA2 gene was performed following previous reports and using PCR. One genetic variant was detected to significantly differ between alcohol-dependent subjects and controls. Two common 8 SNP haplotypes and their complementary alleles were identified containing this SNP and were present in 89.9% of controls and 93.4% of the alcohol-dependent individuals. One of the haplotypes (T-C-A-C-A-T-T-C) was significantly associated with alcohol dependence and characteristics of alcohol withdrawal and severity of alcohol dependence (delirium tremens, withdrawal seizures). These findings support and extend the three previous studies implicating a GABA-A receptor subunit as contributing to the genetic risk for alcohol dependence. Possible implications of these findings are discussed.

Ionotropic glutamate receptor gene GRIK3 SER310ALA functional polymorphism is related to delirium tremens in alcoholics.

Upregulation of glutamatergic neurotransmission resulting from chronic ethanol intoxication may cause a hyperexcitable state during alcohol withdrawal, which may lead to seizures and delirium tremens. The aim of our study was to evaluate the association between a history of alcohol withdrawal-induced seizures and delirium tremens, and a functional polymorphism (Ser310Ala) of the GRIK3 gene coding for the glutamatergic kainate receptor subunit GlurR7 in a sample of well-characterized alcoholics compared to controls. In total, 233 patients meeting DSM-IV alcohol dependence criteria and 309 controls, all of German descent, were investigated. GRIK3 functional polymorphism was determined using PCR (polymerase chain reaction) of lymphocyte DNA. History of alcohol withdrawal-induced delirium tremens and seizures were obtained using the SSAGA (Semi-Structured Assessment for the Genetics of Alcoholism). Data were cross-checked with in-patients' clinical files. While a significant relationship between history of delirium tremens and the Ser310 allele was detected, no significant results were obtained for alcohol withdrawal-related seizures. Although this result is suggestive for a significant role of this polymorphism in the pathogenesis of delirium tremens in alcohol-dependent individuals, further investigation and confirmation are warranted.

No association of CRH1 receptor polymorphism haplotypes, harm avoidance and other personality dimensions in alcohol dependence: results from the Munich gene bank project for alcoholism.

Because corticotrophin-releasing hormone (CRH) plays a central role in stress regulation, the possible role of CRH1 polymorphism for anxiety-related personality variables such as harm avoidance possibly associated with alcoholism was studied. The research instruments used to phenotype patients were adopted partly from the US collaborative study of the genetics of alcoholism and include a number of personality inventories such as the temperament and character inventory (TCI). Based on the examination of 170 alcoholic subjects no association was found between CRH1 receptor haplotypes of four single nuclotid polymorphisms (SNPs) and low and high temperament traits of harm avoidance, novelty seeking and reward dependence. The possible implications of these findings are discussed.

A genome-wide screen for genes influencing conduct disorder.

While behavioral genetic studies have suggested that childhood conduct disorder is under genetic influence, studies aimed at gene identification are lacking. This study represents the first genome-wide linkage analysis directed toward identifying genes contributing to conduct disorder. Genome screens of retrospectively reported childhood conduct disorder and conduct disorder symptomatology were carried out in the genetically informative adult sample collected as part of the Collaborative Study on the Genetics of Alcoholism (COGA). The results suggest that regions on chromosomes 19 and 2 may contain genes conferring risk to conduct disorder. Interestingly, the same region on chromosome 2 has also been linked to alcohol dependence in this sample. Childhood conduct disorder is known to be associated with the susceptibility for future alcohol problems. Taken together, these findings suggest that some of the genes contributing to alcohol dependence in adulthood may also contribute to conduct disorder in childhood.

A 5-year prospective evaluation of DSM-IV alcohol dependence with and without a physiological component.

BACKGROUND: The DSM-III-R removed tolerance and withdrawal as required elements for a diagnosis of alcohol dependence. Although this practice was continued in DSM-IV, the more recent manual asked clinicians to note whether physiological aspects of withdrawal (tolerance and withdrawal) had ever been experienced. Few studies have determined the prognostic meaning of a history of a physiological component to DSM-IV alcohol dependence. METHODS: Face-to-face structured interviews were used to evaluate the course of alcohol, drug, and psychiatric problems during the subsequent 5 years for 1094 alcohol-dependent men and women. These subjects had been classified into subgroups at the time of initial interview regarding evidence of tolerance or withdrawal, and all evaluations were based on DSM-IV criteria. At baseline, the application of DSM-IV diagnostic guidelines resulted in 649 (59.3%) individuals having a history of an alcohol withdrawal syndrome, with or without tolerance (group 1); 391 (35.7%) with histories of tolerance but not withdrawal (group 2); and 54 (4.9%) with no lifetime histories of tolerance or withdrawal (group 3). RESULTS: During the 5-year follow-up, both the broad (group 1 plus 2 versus group 3) and narrow (group 1 versus group 2 plus group 3) definitions of physiological dependence were associated with more alcohol and drug problems. However, for most items, this differential primarily reflected differences between groups 1 and 3, with a less impressive effect by group 2. Although no group differences were noted for the rate of independent major depressive episodes, substance-induced depressions did differentiate among groups, a finding also most closely related to the distinction between groups 1 and 3. CONCLUSIONS: These data support the prognostic importance of noting the presence of a physiological component in alcohol dependence and indicate the potential relevance of limiting the definition of a physiological component to withdrawal.

A comparison of alcohol-induced and independent depression in alcoholics with histories of suicide attempts.

OBJECTIVE: Alcohol-dependent men and women are at high risk for two types of major depressive episodes and for suicide attempts. The aim of this study is to compare the characteristics of two groups: (1) alcohol-dependent subjects with histories of suicide attempts and independent mood disorders and (2) a similar population of alcoholics with histories of self harm but who have only experienced alcohol-induced depressions. METHOD: As part of the Collaborative Study on the Genetics of Alcoholism (COGA), semistructured detailed interviews were administered to 371 alcohol-dependent individuals (62% women) with histories of suicide attempts and major mood disorders. Of the total, 145 (39.1%) had ever had an independent depressive episode and 226 (60.9%) had experienced only alcohol-induced depressions. Information was obtained about socioeconomic characteristics, suicidal behavior, independent and induced psychiatric conditions, and aspects of alcohol dependence. RESULTS: Univariate and multivariate comparisons revealed that alcohol-dependent individuals with a history of suicide attempts and independent depression had a higher number of suicide attempts, were less likely to have been drinking during their most severe attempt, and were more likely to have an independent panic disorder. Univariate analyses indicated that these subjects reported a less severe history of alcohol dependence. CONCLUSIONS: The results indicate that a distinction between independent and alcohol-induced mood disorders in alcoholics with a history of suicide attempts may be useful.

Comparison of 3190 alcohol-dependent individuals with and without suicide attempts.

INTRODUCTION: Suicidal behaviors are often seen in alcohol-dependent individuals. The aim of this study is to identify and confirm risk factors for suicide attempts in a large, family-based sample of alcoholics. METHODS: Semistructured, detailed interviews were administered to 3190 alcohol-dependent individuals as part of the Collaborative Study on the Genetics of Alcoholism (COGA). Information about suicidal behavior, socioeconomic characteristics, psychiatric comorbidity, substance use disorders, and characteristics of alcohol dependence were obtained from alcohol-dependent probands, controls, and their relatives. RESULTS: As determined by both univariate comparison and multivariate logistic regression analysis, alcohol-dependent individuals with a history of suicide attempts were found to have a significantly more severe course of alcohol dependence and a higher prevalence of both independent and substance-induced psychiatric disorders and other substance dependence. First-degree relatives of subjects with suicide attempts showed a significantly higher rate of suicide attempts, even after controlling for additional relevant diagnoses. CONCLUSION: These results support the hypothesis that alcohol-dependent individuals with a history of suicide attempts are more severely impaired. Screening and subsequent treatment of alcohol use disorder, psychiatric comorbidity, and substance use disorders among alcoholics may be crucial in preventing suicide attempts and completions.