Towards a molecular epidemiology of alcohol dependence: analysing the interplay of genetic and environmental risk factors.

BACKGROUND: Progress in identifying genetic factors protective against alcohol dependence (AlcD) requires a paradigm shift in psychiatric epidemiology. AIMS: To integrate analysis of research into the genetics of alcoholism. METHOD: Data from prospective questionnaire and interview surveys of the Australian twin panel, and from a subsample who underwent alcohol challenge, were analysed. RESULTS: In men, effects of alcohol dehydrogenase ADH2*1/*2 genotype or high alcohol sensitivity (risk-decreasing), and of history of childhood conduct disorder, or having monozygotic co-twin or twin sister with AlcD (risk-increasing) were significant and comparable in magnitude. Religious affiliation (Anglican versus other) was associated with the ADH2 genotype, but did not explain the associations with AlcD symptoms. No protective effect of the ADH2*1/*2 genotype was observed in women. CONCLUSIONS: The early onset and strong familial aggregation of AlcD, and opportunity for within-family tests of genetic association to avoid confounding effects, make epidemiological family studies of adolescents and young adults and their families a priority.

Childhood sexual abuse and pathogenic parenting in the childhood recollections of adult twin pairs.

BACKGROUND: We examined the relationship between childhood sexual abuse (CSA), and interviewees' recollections of pathogenic parenting, testing for possible retrospective biases in the recollections of those who have experienced CSA. METHODS: Information about CSA, parental divorce and interviewees' recollections of parental rejection, parental overprotection and perceived autonomy (as assessed through a shortened version of the Parental Bonding Instrument) was obtained through telephone interviews with 3626 Australian twins who had also returned self-report questionnaires several years earlier. Recollections of parental behaviours were compared for individuals from pairs in which neither twin, at least one twin, or both twins reported CSA. RESULTS: Significant associations were noted between CSA and paternal alcoholism and between CSA and recollections of parental rejection. For women, individuals from CSA-discordant pairs reported levels of parental rejection that were significantly higher than those obtained from CSA-negative pairs. The levels of parental rejection observed for twins from CSA-discordant pairs did not differ significantly from those obtained from CSA-concordant pairs, regardless of respondent's abuse status. For men from CSA-discordant pairs, respondents reporting CSA displayed a tendency to report higher levels of parental rejection than did respondents not reporting CSA. Other measures of parenting behaviour (perceived autonomy and parental overprotection) failed to show a clear relationship with CSA. CONCLUSIONS: The relationship between CSA and respondents' recollections of parental rejection is not due solely to retrospective bias on the part of abused individuals and, consistent with other studies, may reflect a pathological family environment with serious consequences for all siblings.

Implementation and day-to-day usage of a client-server-based radiology information system.

Implementation of a second-generation radiology information system (RIS) requires attention to many issues, including work flow, system design, training, consideration for emerging technologies, and support. This presentation covers the issues, and solutions, involved in implementation and subsequent day-to-day usage of a client-server-based RIS tightly integrated with a hospital information system (HIS) using "thin client" software to limit hardware requirements for the client computers. The software and hardware implementation had to be designed for potential enterprise-wide scalability of the RIS for a system involving 11 hospitals. Issues arose regarding initial increased turnaround times, errors in importation of historical data, and problems with implementation of interfaces between the RIS and the billing system and between the RIS and the digital dictation system. Network errors and difficulties in using a thin client implementation had to be overcome. Hierarchical training was implemented, as support was switched from an "on-site" support group to a central Information System Division with responsibility to the entire enterprise.

Early sexual abuse and lifetime psychopathology: a co-twin-control study.

BACKGROUND: This study was designed to determine lifetime prevalence of psychiatric disorders among twins who reported childhood sexual abuse (CSA), and to compare these rates with those among non-abused co-twins. The contribution of familial and individual-specific factors to reported sexual abuse was also examined. METHOD: Information about lifetime psychopathology and substance use was obtained by structured telephone interviews with 5995 Australian twins. Twins who reported a history of childhood sexual abuse (CSA) were contrasted on lifetime psychopathology with subjects without such a history; in addition, comparisons were made between same-sex twin pairs discordant for CSA. RESULTS: A history of CSA was reported by 5.9% of the women and 2.5% of the men. In the sample as a whole, those reporting CSA were more likely to receive lifetime diagnoses of major depression, conduct disorder, panic disorder and alcoholism, and were more likely to report suicidal ideation and a history of suicide attempt. Abused women, but not men, were also more likely to report social phobia. When comparisons were restricted to non-abused co-twins, no differences in psychopathology were seen. However, rates of major depression, conduct disorder and suicidal ideation were higher if both co-twins were abused than if the respondent alone reported CSA. Model-fitting indicated that shared environmental factors influenced risk for reported CSA in women, but not in men. CONCLUSION: The association between CSA and psychopathology arises at least in part through the influence of shared familial factors on both risk of victimization and risk of psychopathology.

Genetic differences in alcohol sensitivity and the inheritance of alcoholism risk.

BACKGROUND: Substantial evidence exists for an important genetic contribution to alcohol dependence risk in women and men. It has been suggested that genetically determined differences in alcohol sensitivity may represent one pathway by which an increase in alcohol dependence risk occurs. METHODS: Telephone interview follow-up data were obtained on twins from male, female and unlike-sex twin pairs who had participated in an alcohol challenge study in 1979-81, as well as other pairs from the same Australian twin panel surveyed by mail in 1980-82. RESULTS: At follow-up, alcohol challenge men did not differ from other male twins from the same age cohort on measures of lifetime psychopathology or drinking habits; but alcohol challenge omen were on average heavier drinkers than other women. A composite alcohol sensitivity measure, combining subjective intoxication and increase in body-sway after alcohol challenge in 1979-81, exhibited high heritability (60 %). Parental alcoholism history was weakly associated with decreased alcohol sensitivity in women, but not after adjustment for baseline drinking history, or in men. High alcohol sensitivity in men was associated with substantially reduced alcohol dependence risk (OR = 0.05, 95% CI 0.01-0.39). Furthermore, significantly decreased (i.e. low) alcohol sensitivity was observed in non-alcoholic males whose MZ co-twin had a history of alcohol dependence, compared to other non-alcoholics. These associations remained significant in conservative analyses that controlled for respondents' alcohol consumption levels and alcohol problems in 1979-81. CONCLUSIONS: Men (but not women) at increased genetic risk of alcohol dependence (assessed by MZ co-twin's history of alcohol dependence) exhibited reduced alcohol sensitivity. Associations with parental alcoholism were inconsistent.

Major depressive disorder in a community-based twin sample: are there different genetic and environmental contributions for men and women?

BACKGROUND: Depression affects more women than men and often aggregates in families. Using a community-based sample of twins, we examined the contributions of genetic and environmental factors to the risk of developing major depressive disorder and the effect of sex and different definitions of depression on the relative contributions of genetic and environmental effects. Sex differences in genetic effects were also studied. METHODS: A volunteer sample of Australian twins (2662 pairs) was interviewed using an abbreviated version of the Semi-Structured Assessment for the Genetics of Alcoholism, a semi-structured lay interview designed to assess psychiatric disorders. Depression was defined using 3 different criteria sets: DSM-III-R major depressive disorder, DSM-IV major depressive disorder, and severe DSM-IV major depressive disorder. Genetic and environmental contributions to the liability to develop depression were estimated using genetic model fitting. RESULTS: Lifetime prevalences were 31% in women and 24% in men for DSM-III-R major depressive disorder, 22% in women and 16% in men for DSM-IV major depressive disorder, and 9% in women and 3% in men for severe DSM-IV major depressive disorder. In women, the simplest model to fit the data implicated genetic factors and environmental factors unique to the individual in the development of depression, with heritability estimates ranging from 36% to 44%. In men, depression was only modestly familial, and thus individual environmental factors played a larger role in the development of depression. For DSM-III-R major depressive disorder, there were statistically different estimates for heritability for men vs. women. For both sexes, the relative contributions of genetic and environmental factors were stable using different definitions of depression. CONCLUSIONS: There was moderate familial aggregation of depression in women and this primarily was attributable to genetic factors. In men, there was only modest familial aggregation of depression. For both men and women, individual environmental experiences played a large role in the development of depression. Major depressive disorder as defined by DSM-III-R was more heritable in women as compared with men. The relative contributions of genetic and environmental factors in the development of depression were similar for varying definitions of depression, from a broad definition to a narrow definition.

Evaluating the impact of workstation usage on radiology report times in the initial 6 months following installation.

Picture archiving and communications systems (PACS) workstations are reported to improve workflow by making studies immediately available for review upon their completion. This study tested the hypothesis that a workstation would decrease the time from completion of a study to dictation of results (report time). A four-monitor, 2K x 2K workstation (Imation Cemax-Icon, Fremont, CA), was installed in a body imaging computed tomography (CT) reading room. Use of the workstation by the staff radiologists was voluntary. Images were also printed on film and films continued to be hung at the routine hanging times. To evaluate the workstation's maximum impact, data were collected for report times for studies completed during the routine day shift of the staff radiologist (Monday to Friday, 8 AM to 5 PM). Data were collected before workstation installation (August 1997 to November 1997) and for the subsequent 6 months. Histograms of the number of studies (743 v 103) versus report time (mean, 11.7 v 7.4 hours) showed a bimodal distribution, with peaks at approximately 6 and 24 hours, both before (8/97-11/97) and after (6/98) the workstation's installation. However, the number of studies dictated greater than 60 hours (25.2% v 20.4%) and the percentage of studies in the second peak (16 to 48 hours; 4.4% v 0%) both decreased. In conclusion, the workstation decreased the mean (11.7 v 7.4 hours) and standard deviation (19.8 v 9.1 hours) for report times. This was due to a decrease in both the number of cases dictated the day following their completion and the number of outliers (markedly delayed dictations). The decrease in outliers is probably due to a decrease in the number of "lost" film-based studies.

Potential psychodynamic factors in physician-assisted suicide.

A number of assumptions underlying the debate over physician-assisted suicide (PAS) deserve closer scrutiny. It is often implicitly assumed that decisions as to the competency of the patient to request PAS can be accurately made, and that the treating physician's values and intrapsychic conflicts can be successfully separated from the decision to accede to or reject the patient's request. This article argues that in such an emotionally-laden decision, such factors may play a significant role, and that even were PAS to gain widespread acceptance, ignoring them may lead to errors in classifying patients either as appropriate or inappropriate for PAS.

Familial transmission of substance dependence: alcohol, marijuana, cocaine, and habitual smoking: a report from the Collaborative Study on the Genetics of Alcoholism.

BACKGROUND: Alcoholism and substance dependence frequently co-occur. Accordingly, we evaluated the familial transmission of alcohol, marijuana, and cocaine dependence and habitual smoking in the Collaborative Study on the Genetics of Alcoholism. METHODS: Subjects (n=1212) who met criteria for both DSM-III-R alcohol dependence and Feighner definite alcoholism and their siblings (n=2755) were recruited for study. A comparison sample was also recruited (probands, n=217; siblings, n=254). Subjects were interviewed with the Semi-Structured Assessment for the Genetics of Alcoholism. The familial aggregation of drug dependence and habitual smoking in siblings of alcohol-dependent and non-alcohol-dependent probands was measured by means of the Cox proportional hazards model. RESULTS: Rates of alcohol, marijuana, and cocaine dependence and habitual smoking were increased in siblings of alcohol-dependent probands compared with siblings of controls. For siblings of alcohol-dependent probands, 49.3% to 50.1% of brothers and 22.4% to 25.0% of sisters were alcohol dependent (lifetime diagnosis), but this elevated risk was not further increased by comorbid substance dependence in probands. Siblings of marijuana-dependent probands had an elevated risk of developing marijuana dependence (relative risk [RR], 1.78) and siblings of cocaine-dependent probands had an elevated risk of developing cocaine dependence (RR, 1.71). There was a similar finding for habitual smoking (RR, 1.77 in siblings of habitual-smoking probands). CONCLUSIONS: Alcohol, marijuana, and cocaine dependence and habitual smoking are all familial, and there is evidence of both common and specific addictive factors transmitted in families. This specificity suggests independent causative factors in the development of each type of substance dependence.

Suicidal behaviour: an epidemiological and genetic study.

BACKGROUND: Psychiatric history, familial history of suicide attempts, and certain traumatic life events are important predictors of suicidal thoughts and behaviour. We examined the epidemiology and genetics of suicidality (i.e. reporting persistent suicidal thoughts or a plan or suicide attempt) in a large community-based sample of MZ and DZ twin pairs. METHOD: Diagnostic telephone interviews were conducted in 1992-3 with twins from an Australian twin panel first surveyed in 1980-82 (N = 5995 respondents). Data were analysed using logistic regression models, taking into account twin pair zygosity and the history of suicidality in the respondent's co-twin. RESULTS: Lifetime prevalence of suicidal thoughts and attempts was remarkably constant across birth cohorts 1930-1964, and across gender. Major psychiatric correlates were history of major depression, panic disorder, social phobia in women, alcohol dependence and childhood conduct problems. Traumatic events involving assault (childhood sexual abuse, rape or physical assault) or status-loss (job loss, loss of property or home, divorce), and the personality trait neuroticism, were also significantly associated with suicide measures. Prevalence of serious suicide attempts varied as a function of religious affiliation. After controlling for these variables, however, history of suicide attempts or persistent thoughts in the respondent's co-twin remained a powerful predictor in MZ pairs (odds ratio = 3.9), but was not consistently predictive in DZ pairs. Overall, genetic factors accounted for approximately 45% of the variance in suicidal thoughts and behaviour (95% confidence interval 33-51%). CONCLUSIONS: Risk of persistent suicidal thoughts and suicide attempts is determined by a complex interplay of psychiatric history, neuroticism, traumatic life experiences, genetic vulnerability specific for suicidal behaviour and sociocultural risk or protective factors.

Common genetic risk factors for conduct disorder and alcohol dependence.

The association between retrospectively reported childhood conduct disorder (CD) and a history of alcohol dependence (AD) was examined in a sample of 2,682 male, female, and unlike-sex adult twin pairs. There was a strong association between CD and AD in both men (tetrachoric r = .34, odds ratio = 2.8) and women (tetrachoric r = .53, odds ratio = 9.9). Genetic factors accounted for most of the association between CD and AD liability in men and women, with the remainder of the association being due to nonshared individual-specific environmental factors. Genetic influences common to CD and AD accounted for 17% and 35% of the genetic variation in AD liability in men and women, respectively, and accounted for 11% and 23% of the total variation in AD liability in men and women, respectively. The results suggest that there are common genetic risk factors for CD and AD or that CD itself is an important genetically influenced risk factor for AD.

Temporal stability of antisocial personality disorder: blind follow-up study at 8 years.

The study objective was to examine the temporal stability of the antisocial personality disorder (ASPD) diagnosis based on whether specific antisocial symptoms were considered to be related to substance abuse. A total of 407 adults who were initially part of a family study of alcoholism and sociopathy were blindly reassessed an average of 8 years later, using the Home Environment and Lifetime Psychiatric Evaluation Record (HELPER) and basing diagnoses on the clinician's best final estimate using all sources of data. "Narrow" and "broad" ASPD diagnoses were made at both times based on whether individual symptoms were counted toward diagnosis if they occurred in the setting of significant substance abuse. kappa values varied from 0.31 to 0.68, with more restrictive methods of diagnosis being less stable. After deriving estimates of sensitivity and specificity of diagnosis, the probability of being a "case" could be assigned based on the reported number of conduct problems occurring before age 15 as a clinical covariate for diagnosis. We conclude that diagnosing ASPD without attempting to attribute the cause of individual symptoms to substance abuse results in substantially greater temporal stability. Using a broader definition, the diagnosis of ASPD is highly sensitive (P = .97) and specific (q = 0.93). These findings may allow more accurate diagnosis of ASPD in drug-abusing individuals.

Genetic and environmental contributions to alcohol dependence risk in a national twin sample: consistency of findings in women and men.

BACKGROUND: Genetic influences on alcoholism risk are well-documented in men, but uncertain in women. We tested for gender differences in genetic influences on, and risk-factors for, DSM-III-R alcohol dependence (AD). METHOD: Diagnostic follow-up interviews were conducted in 1992-3 by telephone with twins from an Australian twin panel first surveyed in 1980-82 (N = 5889 respondents). Data were analysed using logistic regression models. RESULTS: Significantly higher twin pair concordances were observed in MZ compared to DZ same-sex twin pairs in women and men, even when data were weighted to adjust for over-representation of well-educated respondents, and for selective attrition. AD risk was increased in younger birth cohorts, in Catholic males or women reporting no religious affiliation, in those reporting a history of conduct disorder or major depression and in those with high Neuroticism, Social Non-conformity, Toughmindedness, Novelty-Seeking or (in women only) Extraversion scores; and decreased in 'Other Protestants', weekly church attenders, and university-educated males. Controlling for these variables, however, did not remove the significant association with having an alcoholic MZ co-twin, implying that much of the genetic influence on AD risk remained unexplained. No significant gender difference in the genetic variance in AD was found (64% heritability, 95% confidence interval 32-73%). CONCLUSIONS: Genetic risk-factors play as important a role in determining AD risk in women as in men. With the exception of certain sociocultural variables such as religious affiliation, the same personality, sociodemographic and axis I correlates of alcoholism risk are observed in women and men.

Characteristics of injection drug users derived from a large family study of alcoholism.

Most descriptive studies on injection drug users (IDUs) has used treatment or referral samples. This study uses relatives ascertained through the Collaborative Study on the Genetics of Alcoholism (COGA) to describe patterns of drug use, psychiatric comorbidity, and selected high-risk behaviors among IDUs not ascertained through treatment or other referral networks. Relatives (N = 5,520) of alcoholic probands were administered a semistructured interview, the Semistructured Assessment for the Genetics of Alcoholism (SSAGA), which assesses lifetime psychiatric symptoms and psychoactive substance use. IDUs were compared with these who had never used cannabis more than 20 times or other drugs more than 10 times (minimal drug use group), those who had used cannabis more than 20 times but no other illicit drugs more than 18 times (cannabis users), and those who had used other drugs more than 10 times but who had never injected (other drug users). Compared with other drug users, IDUs reported using more classes of drugs and began drug use at an earlier age. IDUs were significantly more likely to receive diagnoses of antisocial personality disorder (ASPD) and alcohol dependence, and reported elevated rates of suicidal ideas and attempts. IDUs were more likely to report a variety of behavioral difficulties beginning before age 15, and were more likely to engage in high-risk sexual behaviors. Half of the IDUs reported having shared needles; shares were more likely to receive a diagnosis of ASPD, but did not differ on reporting high-risk behaviors. IDUs, regardless of whether selected through treatment, have high lifetime rates of mood disturbance and ASPD, and are likely to have a history of conduct difficulties beginning before age 15 years and to subsequently engage in a variety of other high-risk behaviors.

Nicotine withdrawal in women.

Associations between self-report symptom profiles for nicotine withdrawal, personality (TPQ, EPQ-R), life-time history of psychopathology and smoking history were examined in data obtained from 553 female adult Australian twins (246 regular smokers), aged 32-48 years, who had participated in a telephone interview survey that included life-time assessments of smoking history, nicotine dependence and symptoms of withdrawal. Two hundred and two respondents were from high-risk pairs where either the respondent or the respondent's co-twin had reported a life-time history of alcohol dependence; 351 were from control pairs. Latent class analysis was used to identify subtypes ('classes') of smokers reporting similar withdrawal symptom profiles. Three major classes were identified which appeared to represent a continuum from mild to severe nicotine withdrawal. Smokers from the severe withdrawal class were best characterized by hands shaking and by the prominence of depressive features. There were marked increases in life-time alcohol dependence rates as a function of severity class. In contrast, significantly elevated rates of major depression, conduct disorder and anxiety disorder were observed only among smokers from the most severe withdrawal class. Neuroticism was the only personality factor strongly associated with the development of withdrawal symptoms.

Modeling genetic and environmental influences in the etiology of conduct disorder: a study of 2,682 adult twin pairs.

The etiology of conduct disorder (CD) was examined retrospectively in a sample of 2,682 male, female, and unlike-sex adult twin pairs from the community-based Australian Twin Register. Model-fitting analyses indicated a substantial genetic influence on risk for CD, accounting for 71% of the variance (95% confidence interval [CI] = 32-79%). There was not a statistically significant effect of the shared environment in the best-fitting model of CD, but a modest effect of the shared environment on the risk for CD could not be rejected (95% CI = 0-32%). The magnitude of genetic and environmental influences for CD liability did not vary significantly for boys and girls, and the specific genetic and environmental mechanisms important for the development of CD appeared to be largely the same for both sexes. The fit of a multiple-threshold model raises the possibility that CD may not necessarily be a discrete entity but rather an extreme of the normal variation in conduct-disordered behavior found in the general population.

Psychopathology and HIV risk behaviors among injection drug users in and out of treatment.

To replicate prior descriptions of injection drug users (IDUs), 158 IDUs recruited via a street-outreach program were compared to 320 non-IDUs on measures of substance use, lifetime psychopathology, and HIV risk behavior. IDUs were more likely to receive a diagnosis of antisocial personality disorder, but not other psychiatric diagnoses, and to report dependence on multiple substances. IDUs reported more HIV risk behaviors, but perceived HIV risk did not differ from non-IDUs. Compared to IDUs who declined treatment, IDUs willing to accept treatment did not differ on drug-related problems, lifetime psychopathology, or perceived HIV risk.

Reliability and reporting biases for perceived parental history of alcohol-related problems: agreement between twins and differences between discordant pairs.

OBJECTIVE: Previous research suggests that family history of alcoholism assessments may be biased by characteristics of the informant. In this report, the reliability and potential biases in offspring reports of paternal and maternal alcohol-related problems were examined in a large community sample of adult twins. METHOD: Subjects were volunteer participants in the Australian NH&MRC twin registry. Agreement between twin pairs on reports of paternal and maternal alcohol problems was assessed in 2,657 twin pairs (1,444 female-female pairs, 626 male-male pairs, and 587 female-male pairs). In addition, to detect systematic reporting biases, like-sex twin pairs whose paternal alcohol problems reports disagreed (n = 164) were contrasted on measures of personality, state anxiety and depression, parental rearing, alcoholism, and alcohol use. RESULTS: Twin agreement for parental alcohol-related problems was good, with overall kappas of .66 for paternal and .58 for maternal alcohol problems. When discordant twin pairs were compared, we found that women who reported that their father had alcohol problems were significantly lower on EPQ-R Social Conformity than their twin sister who denied paternal alcohol problems: and there was a trend for men who reported that their father had alcohol problems to be higher in negative perceived parenting from father than their twin brother who denied paternal alcohol problems. Twins discordant for reporting paternal alcohol problems did not, however, differ on the major dimensions of personality, state anxiety and depression, alcoholism, or current alcohol use. CONCLUSIONS: The results of this study bolster our confidence in using the family history method to examine characteristics of offspring of alcoholics versus offspring of nonalcoholics on self-reported measures of personality and psychopathology, but suggest that some caution should be exercised when using this method to examine differences in offspring-reported perceptions of parental rearing practices.

Genetics, antisocial personality, and criminal responsibility.

There is now substantial evidence that heritable biological factors play a role in the genesis of repetitive antisocial behavior. The differing conceptual frameworks of behavioral genetics and the law are described, and the implications that current research in behavioral genetics may have for assigning responsibility for unlawful behavior are discussed.

Combined alfentanil-methohexital anesthesia in electroconvulsive therapy.

Eight patients receiving electroconvulsive therapy (ECT) were anesthetized with alfentanil, 25 mcg/kg, plus 20 mg methohexital, alternating with standard methohexital anesthesia. Combination alfentanil-methohexital anesthesia was associated with a 45% increase in EEG seizure duration. Preliminary evidence suggests that ECT anesthesia using short-acting opiate compounds may prove to be a promising alternative to standard modified ECT, especially for patients with brief seizures.