Drug Abuse Prevention

Research Findings from February, 1999 Director's Report

This section lists selected summaries from NIDA funded research projects that investigate youth drug abuse prevention. The summaries provided were selected from recent issues of the Director's Report to the National Advisory Council on Drug Abuse. For a more comprehensive listing of NIDA funded projects see the Director's Report.

Several 'Endophenotypes' Have Been Described as Possible Markers for Drug Abuse Vulnerability

William G. Iacono and colleagues at the University of Minnesota have reported psychophysiological measures associated with increased risk for drug abuse. One example is based on "preception" -- ability to take advantage of the predictability of an aversive event to diminish its psychological impact; the second, on "antisaccades" -- the ability to generate a saccade in the direction opposite to an abrupt movement of tracking target. In the preception experiment, subjects watched the sweep hand of a clock and were told that a loud, unpleasant noise would be heard at infrequent times. Sometimes these blasts would be predictable by appearance of a warning stimulus; other times there would be no warning. Skin Conductance Responses (SCRs) and Heart Rates (HRs) were measures of how well the subjects made use of the warning information. Results showed that poor modulators -- individuals whose SCRs were higher for the predictable loud noises and whose HRs did not differentiate predictable from non-predictable -- had significantly more symptoms of alcohol and nicotine dependence. These results were interpreted as biologically based support for the theory that individuals at risk for substance dependence have poor inhibitory control related to a dysfunctional Behavioral Inhibition System (BIS). Taylor, J., Carlson, S.R., Iacono, W.G., Lykken, D.T., and McGue, M. Individual Differences in Electrodermal Responsivity to Predictable Aversive Stimuli and Substance Dependence. Psychophysiology, 36, pp. 1-6, 1998. In the antisaccade experiment, subjects are required to make an eye movement in the direction opposite to a moving target which is contrary to natural tendency. Those who are less successful are said to have a more faulty control on inhibitory mechanisms. The results showed a higher error rate in this task among "high risk" 17 year-old boys compared to "low risk" boys. (High and low risk are defined as to whether fathers did or did not have a diagnosis of illicit drug abuse or dependence with co-morbid antisocial personality disorder). Additionally MZ twins discordant for drug abuse/dependence were nevertheless concordant for high error rates, suggesting a genetically based susceptibility for this deficit independent of diagnosis. Iacono, W. G. Identifying Psychophysiolgical Risk for Psychopathology: Examples from Substance Abuse and Schizophrenia Research. Psychophysiology, 35, pp.1-17, 1998.

Drug Use in Sons of Fathers with Substance Use Disorders

In a study using the CEDAR cohort at the University of Pittsburgh to determine the relevance of preadolescent psycho-pathology and substance use for predicting early adolescent alcohol and cannabis involvement, sons of substance dependent fathers (High Risk or HR, n=102) and sons of fathers without lifetime substance use disorder diagnoses (Low Average Risk or LAR, n=164) were assessed at age 10-12 and again at ages 12-14 using similar semistructured interviews that obtained measures of psychopathology and substance use behavior. Preadolescent tobacco experimentation and early adolescent regular alcohol use were more prevalent in HR than in LAR subjects. Logistic regression analyses were conducted to evaluate the effects of preadolescent psychopathology and substance use behavior on early adolescent substance use behavior. Preadolescent conduct disorder and tobacco use were found to be highly predictive of early adolescent marijuana use. Preadolescent conduct disorder alone predicted adolescent alcohol use. Adolescent tobacco use was predicted by the presence of preadolescent oppositional defiant disorder. Preadolescent anxiety disorders appeared to protect against adolescent tobacco use. The association between early cigarette smoking in preadolescence and later adolescent smoking of marijuana found in this study suggests that reduction of childhood tobacco use may be a valuable goal for prevention programs that seek to forestall the developmental trajectory toward cannabis and other drug use behavior. Clark, D.B., Kirisci, L., Moss, H.B. Addictive Behaviors, 23, pp. 561-566, 1998.

Familial and Nonfamilial Factors in the Prediction of Disruptive Behaviors in Boys at Risk of Substance Abuse

Researchers using the CEDAR cohort sought to identify (1) a core disruptive behavior disorder (DBD) postulated to presage a substance use disorder, and (2) the relative importance of parental DBD phenotypes, and familial and nonfamilial environmental factors in the determination of DBD in male children (aged 10-12 yrs). DBD symptom counts and measures of familial and nonfamilial environmental variables were collected from intact families ascertained through the presence (SA+) or absence (SA-) of substance dependence in fathers. DBD symptom counts for sons were based on symptoms of Conduct Disorder (CD), Oppositional Defiant Disorder (ODD), and Attention Deficit Hyperactivity Disorder (ADHD); counts for parents reflected historical CD and ODD and current Antisocial Personality Disorder (ASPD). Sons' psychiatric assessments were based on K-SADS-E interviews with sons supplemented by mothers' reports on their sons. Familial environmental factors reflected the shared environment including social and physical aspects of the neighborhood and the home, and nonfamilial environmental variables referred to similar factors impacting only individual family members. Multivariate analyses revealed that both behavioral symptoms and environmental measures were significant discriminators of the families. In SA+ families, the child's DBD score was best predicted by magnitudes of parental dyssocial behaviors and by familial environmental factors. However, in SA- families, only familial environmental factors were significant predictors of the child's DBD. These findings suggest that in addition to independent contributions of familial and nonfamilial factors, strong genotype-environment interactions may determine DBD in children and that may contribute to the liability for a substance use disorder. Majumder, P.P., Moss, H.B. Murrelle, L. Journal of Child Psychology & Psychiatry & Allied Disciplines. Vol. 39(2), pp. 203-213, 1998.

Secondary Prevention Effects Among High Risk Adolescents

Recent reviews of the prevention literature raise the question of whether primary prevention programs deter use among youth at highest risk for drug abuse. This study examines the secondary prevention effects of the Midwestern Prevention Project (MPP) in Indianapolis (I-STAR). Prevalence rate comparisons and logistic regression were conducted on four waves of follow-up data from sixth and seventh grade baseline users of cigarettes, alcohol, and marijuana who received a social influences-based curriculum in Indianapolis, Indiana. Across four follow-ups, baseline substance users in the program group consistently demonstrated higher rates of reduced use for all three types of substances relative to the control group, except the 3.5 year follow-up for baseline marijuana users. The logistic regression models evaluated at each follow-up demonstrated statistically significant secondary prevention effects on cigarettes at the initial follow-up (6 month), and on alcohol for the first two follow-ups (up to 1.5 years). Models considering repeated measures structure showed significant secondary prevention effects on all three substances (adjusted odds ratios are 1.53, 1.54, and 3.96 for cigarettes, alcohol, and marijuana, respectively). Social influences, school-based, primary prevention programs are able to successfully reach and influence high risk adolescents in a non-stigmatizing manner. Chou, C.P., Montgomery, S., Pentz, M.A., Rohrbach, L.A., Johnson, C.A., Flay, B.R., MacKinnon, D.P. Effects of A Community-Based Prevention Program on Decreasing Drug Use in High Risk Adolescents. American Journal of Public Health, 88, pp. 944-948, 1998.

Effect of Father Involvement on Adolescent Substance Use

This study examined the effects of family process, father involvement, and family structure on 679 urban African-American adolescents, 14-17 year olds (50% female). Findings revealed that involvement of fathers, whether or not they live with their adolescent child, was associated with less substance use and psychological distress. Father effects were mediated by parental support and family conflict. Family structure was not related to any drug use or psychosocial outcome. The results challenge the assumption that nonresident fathers are absent from urban African-American youth's lives and that living in single mother households has adverse effects on youths' development. These findings, which replicate those in another sample, suggest single mother households do not automatically translate into absent fathers, and that interventions that focus on fathers in particular may be a useful approach for drug prevention programs. Salem, D.A., Zimmerman, M.A., Notaro, P.C. Family Relations, 47, pp. 331-341, 1998.

Marijuana Use and Academic Achievement in Mexican American Students

This study sought to examine the relationship between academic achievement (as measured by standardized achievement scores), substance use, and related psychosocial factors among Mexican American school-age students. Surveys were conducted with 2,165 middle school students who identified themselves as Mexican American. Survey items asked about use of marijuana in the last year, as well as indices of student characteristics (susceptibility to peer influence, dysphoria, school satisfaction, self-esteem, academic achievement). Results of the analyses revealed a complex relationship among risk factors, marijuana use, academic achievement, and gender. One risk factor in particular, peer susceptibility, distinguished marijuana users from non-users, regardless of level of academic achievement for both males and females. In addition, a higher percentage of males than females were found to smoke marijuana, suggesting that, even among students who were academically talented, males were more susceptible to marijuana use than females. The findings suggest that prevention and mediation programs should focus their efforts on risk factors that may be applicable for all students (such as peer susceptibility) in addition to targeting risk factors that are more significant for identified subgroups, such as males and females. In this way, the complex issue of substance use and abuse among our young can be addressed more effectively. Codina, G.E., Yin, Z., Katims, D.S., and Zapata, J.T. Marijuana Use and Academic Achievement Among Mexican American School-Age Students: Underlying Psychosocial and Behavioral Characteristics. J. Child & Adolescent Substance Abuse, 7(3), pp. 79-96, 1998.

Project Towards No Tobacco Use

Project Towards No Drug Abuse (Project TND) is a large-scale indicated drug abuse prevention program for continuation (i.e., alternative) high school youth who are at high risk for drug abuse. The efficacy of a nine-lesson health motivation social skills decision-making curriculum was evaluated in a three-condition experimental design. Twenty-one schools were randomly assigned to one of three conditions: standard care (control), classroom program, and classroom program plus a semester-long school-as-community component. A pretest in all 21 schools was followed by a three week long drug abuse prevention program in the 14 intervention schools. At the completion of the program a post-test was conducted in all 21 schools, and repeated after one year. Changes in use of cigarettes, alcohol, marijuana, and other drugs were assessed in a pretest-one year follow-up time comparison with a follow-up rate of 67% (analysis n=1074). Lower levels of alcohol and other drug use were found for the intervention groups without significant differences between the two program conditions. Project TND is the first limited session school-based model to demonstrate one-year behavioral effects on alcohol and other drug use among older, high-risk youth. Sussman, S. et al. One-year Outcomes of Project Towards No Tobacco Use. Preventive Medicine, 27, pp. 632-642, 1998.

Patterns of Cigarette Smoking in Late Childhood

Early initiation of cigarette smoking so strongly predicts future smoking that several investigators have advocated delaying the age of initiation as a prevention strategy. To complement retrospective studies of early initiation, this study assessed prospectively patterns of smoking behavior in a sample of 401 children who were surveyed in the 4th, 5th and 6th grades. The principal findings were: (1) modeling of smoking by parents and friends is sufficient to influence children to initiate smoking, particularly when children also have low behavioral self-control, and (2) when modeling occurs in combination with poor adjustment to school, low parental monitoring, easy access to cigarettes, and other risk attributes, early initiators are significantly more likely to continue smoking. Jackson, C. et al., A Longitudinal Study Predicting Patterns of Cigarette Smoking in Late Childhood. Health Education and Behavior, 25(4), pp. 436-447, 1998.