Bipolar Disorder Not Conduct Disorder Linked to Risk
"We were the first to report on the association of bipolar disorder and substance abuse," lead study author Timothy E. Wilens, MD, from Massachusetts General Hospital and Harvard Medical School, in Boston, Massachusetts, told Medscape Psychiatry in an email. The current findings replicate a smaller and less controlled initial study and "highlight the massive risk that bipolar disorder bestows upon the development of substance abuse and that it is bipolar disorder and not conduct disorder (juvenile delinquency) that is associated with that risk," he added.
In this study, the risk from bipolar disorder for substance abuse is among the highest risk ever described in the literature and is equal to the risk from conduct disorder, he continued. The study "shows that yet again, the onset of bipolarity in adolescence is particularly malignant for the onset of substance abuse," he said.
The implications for clinical practitioners are huge, he continued. All patients with bipolar disorder need to be educated about the risk for substance abuse, and conversely, all substance-abusing youth with mood instability need to be carefully screened for bipolar disorder, he said.
Future studies might discover intervention points where practitioners could reduce the influence of bipolar disorder on drug and alcohol abuse, he added. One small, older, controlled study (Geller et al. J Am Acad Child Adoles Psych. 1997;36:1168-1176) showed that if a youth has bipolar disorder and substance abuse and the bipolar disorder is treated, the risk for substance abuse and patient functioning are dramatically improved, he added.
It has been estimated that 20% of children and adolescents treated for psychiatric problems have bipolar disorder, the group writes. A few studies suggest that juvenile-onset bipolar disorder may be a major risk factor for substance-abuse disorder, but study limitations hinder the interpretation of these findings.
The group aimed to reexamine the association between bipolar disorder and substance abuse in adolescents in a case-controlled study. They hypothesized that the association between bipolar disorder and substance-abuse disorder would be independent of psychiatric comorbidity with attention deficit/hyperactivity disorder (ADHD), conduct disorder, and multiple anxiety disorder.
The current study is based on baseline assessments from an ongoing study of bipolar disorder in adolescents.
The investigators examined 105 subjects with bipolar disorder (mean age 13.6 ± 2.5 years, 70% male) and 98 controls (mean age 13.7 ± 2.1 years, 60% male); all participants were recruited form the community.
Diagnosis of bipolar disorder and other psychiatric disorders were made using Diagnostic and Statistical Manual of Mental Disorders, 4th ed structured interviews. Substance-abuse–disorder information was based on in-depth interviews with the child and with the parents.
Findings Support Importance of Screening Teens
The incidences of any substance-use disorder, alcohol abuse, drug abuse, drug dependence, and cigarette smoking were each significantly higher in the participants with bipolar disorder compared with the control subjects.
Risk of Substance Use Among Youth With vs Without Bipolar Disorder*
Substance Use Incidence in Bipolar Youth
(%) Incidence in Control Youth
(%) Risk Ratio (95% CI) P
Lifetime prevalence of any substance use disorder 34 4 8.68 (3.02 – 25.0) < .001
Alcohol abuse 23 3 7.66 (2.20 – 26.7) .001
Drug abuse 22 1 18.5 (2.46 – 139.1) .005
Drug dependence 14 1 12.1 (1.54 – 95.5) .02
Cigarette smoking 22 4 12.3 (2.83 – 53.69) < .001
*Adjusted for age and independent of attention deficit/hyperactivity disorder (ADHD), conduct disorder, and multiple anxiety disorder.
No control subjects but 14% of subjects with bipolar disorder had both drug- and alcohol-use disorder (P < .001).
This work indicates that young people with bipolar disorder need to be carefully screened for substance abuse, and adolescents known to abuse drugs and alcohol — especially those who binge use — should also be assessed for bipolar disorder, Dr. Wilens summarized.
Dr. Wilens acknowledges receiving research support from, being a speaker for, or being on the advisory board of the National Institute on Drug Abuse and the following pharmaceutical companies: Abbott Laboratories, Ortho-McNeil, Eli Lilly, Novartis Pharmaceuticals, and Shire Laboratories. The financial disclosures of the other authors are listed in the paper.
Drug Alcohol Depend. 2008;95:188-198. Abstract