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FAMILY, ADOPTION, AND TWIN STUDIES have demonstrated that substance-use disorders--including smoking and nicotine dependence--'run' in families along with non-substance-use psychiatric disorders (Cadoret, 1978; Fu et al., 2002; Herndon and Iacono, [...], Objective: It is not known if parental psychiatric disorders have an independent effect on offspring smoking after controlling for genetic and environmental vulnerability to nicotine dependence. We tested if parental alcohol, drug, or conduct disorders; antisocial personality disorder; depression; and anxiety disorders remained significant predictors of offspring smoking initiation, regular smoking, and nicotine dependence before and after adjusting for genetic and environmental risk for nicotine dependence. Method: Data were obtained via semistructured interviews with 1,107 twin fathers, 1,919 offspring between the ages of 12 and 32, and 1,023 mothers. Genetic and environmental liability for smoking outcomes was defined by paternal and maternal nicotine dependence. Multinomial logistic regression models were computed to estimate the risk for offspring trying cigarettes, regular smoking, and the Fagerstrom Test for Nicotine Dependence (FTND) as a function of parental psychopathology and sociodemographics before and after adjusting for genetic and environmental vulnerability to nicotine dependence. Results: Before adjusting for genetic and environmental risk for nicotine dependence, ever trying cigarettes was associated with maternal depression, regular smoking was associated with maternal alcohol dependence and maternal conduct disorder, and FTND was associated with paternal and maternal conduct disorder and antisocial personality disorder. No parental psychopathology remained significantly associated with regular smoking and FTND after adjusting for genetic and environmental vulnerability to nicotine dependence in a multivariate model. Conclusions: The association between parental psychopathology and offspring smoking outcomes is partly explained by genetic and environmental risk for nicotine dependence. Point estimates suggest a trend for an association between parental antisocial personality disorder and offspring regular smoking and nicotine dependence after adjusting for genetic and environmental vulnerability. Studies in larger samples are warranted.

ALCOHOL DEPENDENCE, drug dependence, and conduct disorder frequently co-occur, and this comorbidity appears to be the result of common etiological factors, including underlying genetic covariation (Button et al., 2007). Also, [...], Objective: Not only are substance-use disorders and externalizing disorders frequently comorbid, they often co-occur in families across generations. The current study examined the role of genetic and environmental influences in the relationship between paternal histories of drug dependence or alcohol dependence and offspring conduct disorder using an offspring-of-twins design. Method: Participants were male twins (n = 1,774) from the Vietnam Era Twin Registry, their offspring (n = 1,917), and mothers of the offspring (n = 1,202). Twins had a history of drug dependence, alcohol dependence, or neither. Based on the father's and his co-twin's drug-dependence or alcohol-dependence history and zygosity, risk groups were constructed to reflect different levels of genetic and environmental risk that were then used to predict offspring conduct disorder. Results: After controlling for potentially confounding variables, the offspring of men with a history of drug dependence or alcohol dependence had significantly higher rates of conduct disorder, compared with offspring of men without this history. Offspring at higher genetic risk had higher rates of conduct disorder. High-risk offspring at lower environmental risk had lower rates of conduct disorder but only in the case of paternal drug-dependence risk. Lower environmental risk did not influence rates of offspring conduct disorder when the father had an alcohol-dependence history. Conclusions: Genetic risk associated with both paternal drug-dependence and paternal alcohol-dependence histories predicted offspring conduct-disorder risk, but only risk associated with paternal drug-dependence history was mitigated by having a low-risk environment. These results demonstrated a significant gene-environment interaction effect.

THE PROPORTION OF AMERICAN WOMEN who are overweight or obese has increased dramatically in the past 50 years. According to recent data from the National Health and Nutrition Examination Survey [...], Objective: The aim of this study was to examine the relationships between body mass index (BMI) and alcohol use and misuse in young adulthood in a sample of black and white female twins. Method: Cox proportional hazards and logistic regression models were used to examine the relationships between BMI category and first alcohol use, current weekly alcohol use, and current weekly heavy episodic drinking in 3,514 (14.06% black) young adult female twins. Analyses were conducted separately in black and white women. Results: After adjusting for relevant covariates, in white women obesity was protective against alcohol use (hazard ratio = 0.83; 95% confidence interval [CI]: 0.73-0.93) and against weekly drinking (odds ratio [OR] = 0.36; 95% CI: 0.24-0.53) and weekly heavy episodic drinking (OR = 0.51; 95% CI: 0.31-0.82) among ever drinkers compared with women of ideal weight. Overweight women living with their parents were less likely to be weekly drinkers (OR = 0.31; 95% CI: 0.16-0.61), whereas overweight women who were not living with their parents were less likely to be weekly heavy episodic drinkers (OR = 0.51; 95% CI: 0.31-0.82). Among black women, obesity was not associated with any of the drinking outcomes; however, black women who were overweight and who reported that the majority of their friends were not weekly drinkers had greater odds of reporting weekly drinking than those of ideal weight (OR = 2.91; 95% CI: 1.33-6.39). Conclusions: Obese white women were less likely to ever use alcohol, be weekly drinkers, or be weekly heavy episodic drinkers than their ideal-weight peers. Body weight may affect drinking behavior in young women, and this effect may differ by race. Future research is needed to identify mediators and moderators of this relationship as well as to explore racial differences in the effect of body weight on drinking behavior.

MEASURES OF SUBSTANCE-USE PROBLEMS as defined by the Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition (DSM-IV; American Psychiatric Association, 1994), are becoming more widely applied in genomic studies [...], Objective: The purpose of this study was to develop a quantitative measure of alcohol consumption for gene-mapping studies. Method: Using a sample of 3,787 young-adult twin women and an independent sample of 489 men and women from a college drinking study, we developed an alcohol-consumption factor score indexed by (1) maximum typical consumption (log-transformed quantity frequency [LQNTFRQ]), (2) maximum drinks in a 24-hours period (LMAXALC), (3) frequency of drinking five or more drinks per day (FIVE), and (4) frequency of drinking to intoxication (INTOX). We tested (1) for factorial and psychometric equivalence across samples and genders; (2) for construct validity and its equivalence, across samples and genders, using measures of tobacco and cannabis use and family history of alcoholism; and (3) to determine the heritability of the alcohol-consumption factor score using a genetic psychometric model. Results: A single-factor model fit well with factor loadings ranging from .60 to .90. With rare exception, we found support for measurement invariance across the two samples and across genders. Measures of nicotine and cannabis use as well as family history of alcoholism were associated, to a similar extent across samples and genders, with the underlying alcohol-consumption factor. Psychometric twin modeling revealed that each of the alcohol-consumption measures ([h.sup.2] - 34%-47%) and the underlying factor score ([h.sup.2] - 50%) were heritable, with the remainder of the variance attributable to individual-specific environmental factors. This moderately heritable alcohol-consumption factor also accounted for a majority of the genetic variance in LQNTFRQ, LMAXALC, FIVE, and INTOX. Conclusions: Quantitative measures of alcohol consumption with the favorable attributes of measurement invariance, construct validity, and moderate heritability can greatly enhance future gene-mapping efforts, supplementing information afforded by conventional diagnostic measures of alcohol abuse/dependence.

To link to full-text access for this article, visit this link: http://dx.doi.org/10.1016/j.addbeh.2006.03.046 Byline: Alexandre A. Todorov (a), Michael T. Lynskey (a), Julia D. Grant (a), Jeffrey F. Scherrer (a)(b), Richard D. Todd (a), Kathleen Keenan Bucholz (a) Keywords: Alcohol use disorder; Substance use disorder; Psychiatric co-morbidity; Genetic association study Abstract: Psychiatric comorbidity with drug dependence has been widely documented. In the present study, we reanalyze DSM-III-R diagnostic data on middle-aged male twin pairs from the VETR study using latent class methods. We identify four subtypes based on 15 diagnostic categories. We then show that these subtypes are strongly associated with differential rates of transitions in drug use histories, with increased risks in relatives for depression, alcohol, drug and ASPD, as well as with a variety of non-normative and deviant behaviors in youth and in adulthood. We use the result of these analyses to show how the use of a particular drug disorder phenotype for selecting cases could impact final sample composition. Author Affiliation: (a) Department of Psychiatry, Midwest Alcoholism Research Center, Washington University School of Medicine, 660 South Euclid Avenue, Box 8134, St. Louis, MO 63110-1502, United States (b) Research Service, St. Louis VAMC, St. Louis, MO, United States

To link to full-text access for this article, visit this link: http://dx.doi.org/10.1016/j.addbeh.2005.02.007 Byline: Julia D. Grant (a), Jeffrey F. Scherrer (a)(b), Michael J. Lyons (c), Ming Tsuang (d), William R. True (b)(e), Kathleen K. Bucholz (a) Keywords: Subjective effects; Cocaine; Marijuana; Abuse; Dependence Abstract: Subjective effects of marijuana and cocaine use are associated with amount of drug use and potentially with risk of abuse and dependence. We used Latent Class Analyses (LCA) to examine subjective responses to two categories of drugs and link these to abuse and dependence. In 1992, subjective responses were queried of 2506 marijuana and 661 cocaine lifetime users who were members of the Vietnam Era Twin Registry. LCA was used to identify classes of subjective effects. Multinomial logistic regression models were computed to test for an association between classes and marijuana and cocaine abuse or dependence. The best LCA solution for marijuana identified 6 distinct classes characterized as positive, relaxed, reactive, adverse, low and very reactive. The best LCA solution for cocaine identified 5 distinct classes characterized as positive, alert, adverse, low and very reactive. Marijuana abuse and dependence were significantly associated with each latent class. Cocaine abuse was associated with the reactive class (OR=3.9; 95% CI: 1.6-9.5). Cocaine dependence was associated with reactive (OR=15.3; 95% CI: 7.1-32.6), adverse (OR=9.7; 95% CI: 4.5-21.0) and very reactive (OR=18.7; 95% CI: 5.6-62.6) classes. We found evidence for both qualitative and quantitative subjective effect profiles. Subjective effects, both positive and adverse are associated with lifetime risk for marijuana and cocaine dependence. Author Affiliation: (a) Department of Psychiatry, Midwest Alcoholism Research Center, Washington University School of Medicine, 40 N. Kingshighway, Suite 3, St. Louis, MO 63108, United States (b) Research Service, St. Louis VAMC, St. Louis, MO, United States (c) Department of Psychology, Boston University, Boston, MA, United States (d) Institute of Behavioral Genomics, Department of Psychiatry, U of California San Diego, San Diego CA, Harvard Institute of Psychiatric Epidemiology and Genetics, Harvard Departments of Epidemiology and Psychiatry, Boston MA, United States (e) School of Public Health, Saint Louis University, St. Louis, MO, United States

This study investigates the effects of genetic and environmental influences on perceived control of health in octogenarian twins. Results indicate that there were modest associations between health related beliefs and measures of well-being such as depression, life satisfaction, and hospitalization.