Addicted to Nicotine
A National Research Forum

Section II: Nicotine-Individual Risk Factors for Initiation
Richard R. Clayton, Ph.D., Chair

CHILD AND ADOLESCENT PSYCHOPATHOLOGY AS RISK FACTORS FOR TOBACCO USE

Robert J. McMahon, Ph.D.
Child Clinical Psychology Program
University of Washington

Introduction

Initiation of tobacco use is most likely to occur prior to age 18, and initiation during childhood or adolescence is associated with an increased likelihood of daily tobacco use as an adult. For example, 89 percent of adult daily smokers began using cigarettes by or at age 18, and 71 percent began smoking daily by or at age 18. There seems to be considerable individual variation in vulnerability to initiation of tobacco use and progression to regular use and dependence. The 1994 Institute of Medicine report highlighted the need to identify factors that influence individual vulnerability to nicotine addiction.

There is a growing body of research that suggests that a number of types of psychopathology that occur during childhood and adolescence are associated with an increased risk for tobacco use. The purpose of this presentation is to assess the relationship between several types of child and adolescent psychopathology and tobacco use. Types of psychopathology to be discussed include conduct problems (e.g., oppositional defiant disorder, conduct disorder); attention-deficit hyperactivity disorder (ADHD), and internalizing disorders (depression, anxiety disorders).

What We Know

The strongest evidence for connections between child and adolescent psychopathology and tobacco use is for conduct problems, ADHD, and depression. There is much weaker support for a connection between anxiety disorders and tobacco use.

• Conduct Problems. The relationship between child and adolescent conduct problems and subsequent tobacco use appears to be quite robust. The relationship has been demonstrated both cross-sectionally and longitudinally and in community and high-risk samples. Conduct problems have been operationalized as dimensions (e.g., oppositional and aggressive behavior) and as DSM categories (e.g., conduct disorder). They have been measured as early as the first grade, although most studies have assessed conduct problems in middle childhood and adolescence. Conduct problems have predicted various aspects of tobacco use, including age of initiation and regular (e.g., daily) smoking. There have been minimal gender differences; when they do exist, they have shown the relationship between conduct problems and tobacco use for boys but not girls.

• ADHD. A number of prospective studies have documented a relationship between ADHD (or ADHD symptomatology) and tobacco use. Many of these studies have been with clinical samples of boys, although the relationship has been found for boys and girls in community samples as well. ADHD is associated with more frequent tobacco use and an earlier age of initiation. The relationship between ADHD and tobacco use seems to be mediated in most cases by coexisting conduct problems. Youth with comorbid conduct problems and ADHD are at especially high risk for tobacco use. In some studies, ADHD alone, in the absence of co-occurring conduct problems, has not been associated with later tobacco use.

• Depression. Several cross-sectional and longitudinal studies (primarily with community samples) have shown that the presence of depressive symptoms or a diagnosis of major depression is associated with an increased likelihood of tobacco use or nicotine dependence. This finding holds after controlling for other types of psychopathology and social/contextual variables. Prospective studies have demonstrated that depression in adolescence is associated with increased levels of tobacco use 1 year to 9 years later. There has been minimal evidence of gender differences. There appears to be a reciprocal relationship between depression and tobacco use, suggesting that the relationship may be due to common genetic and/or environmental vulnerability factors.

• Anxiety. In contrast to other forms of child and adolescent psychopathology, relatively less attention had been paid to various anxiety disorders and symptoms and their possible relationship to tobacco use. There has been great variability in how anxiety has been conceptualized across these few studies, and most studies have failed to find a significant relationship between anxiety and tobacco use. One cross-sectional study demonstrated a relationship between a composite measure of DSM anxiety disorders (for boys, but not girls) and tobacco use. However, in other cross-sectional and longitudinal studies, DSM anxiety disorders, avoidant personality disorder, and "shyness" were not associated with subsequent tobacco use.

What We Need To Know More About

• Effects of a Particular Psychopathology on Various Aspects of Tobacco Use. Does the psychopathology increase the risk of tobacco use in general (and thus lead to more tobacco users), increase the risk of tobacco use at an earlier age (which is associated with increased risk of dependence), or both? Does the psychopathology affect initiation, regular use, and/or dependence? Are these effects specific to a particular subtype of the disorder? To what extent do these effects hold across different types of psychopathology?

• Comorbidity of Psychopathologies. With the exception of comorbid conduct problems with ADHD, relatively little is known about whether youth who are comorbid for other psychopathology (e.g., conduct problems plus depression, depression plus anxiety) have increased risk status with respect to tobacco use.

• Protective Factors. Why do some youth with these psychopathologies not use tobacco? Do they differ in their risk profiles and/or in the timing of risk factors?

• Moderators. How are the effects of these psychopathologies on initiation of tobacco use moderated by factors such as gender and ethnicity?

• Mechanisms and Processes. Simply knowing that a child/adolescent displays a particular disorder and is therefore at increased risk for initiation of tobacco use is only part of the story. What are the "active ingredients" of various psychopathologies that put these youth at high risk for tobacco use, that is, what are the mechanisms and processes by which they are more likely to use tobacco than other youth? To what extent is the relationship between psychopathology and tobacco use due to a common risk factor(s)? Greater attention to the identification of various developmental pathways that culminate in tobacco use should facilitate progress in this area. (This has important implications for prevention.)

• Intervention. What are the implications of the associations between child and adolescent psychopathology and tobacco use with respect to intervention? Does the provision of effective intervention for the psychopathology prior to tobacco use also decrease the risk of subsequent tobacco initiation or progression (i.e., does the intervention serve a preventive function with respect to tobacco use)? Are broadband interventions directed specifically at the prevention of tobacco use in children and adolescents differentially effective with individuals who display these various psychopathologies?

• Cohort Effects. As tobacco use becomes increasingly frowned upon by society, will it become increasingly associated with conduct problems, a feature of which is "rebelliousness"?

Recommended Reading

Brown, R.A.; Lewinsohn, P.M.; Seeley, J.R.; and Wagner, E.F. Cigarette smoking, major depression, and other psychiatric disorders among adolescents. J Am Acad Child Adolesc Psychiatry 35:1602-1610, 1996.

Kellam, S.G.; Ensminger, M.E.; and Simon, M.B. Mental health in first grade and teenage drug, alcohol, and cigarette use. Drug Alcohol Depend 5:273-304, 1980.

Lynskey, M.T., and Fergusson, D.M. Childhood conduct problems, attention deficit behaviors, and adolescent alcohol, tobacco, and illicit drug use. J Abnorm Child Psychol 23:281-302, 1995.

Millberger, S.; Biederman, J.; Faraone, S.V.; Chen, L.; and Jones, J. ADHD is associated with early initiation of cigarette smoking in children and adolescents. J Am Acad Child Adolesc Psychiatry 36:37-44, 1997.