Common Liabilities in Internalizing Symptoms and Cigarette Use in Adolescence

Area of Science:

• Adolescent behavioral development
• Psychiatric genetics
• Substance use research

Background:

• Substance use and mood disorders represent a significant global health burden, particularly impacting adolescents.
• Internalizing symptoms and cigarette use often co-occur during adolescence, a critical period for the onset of these issues.

Purpose of the Study:

• To investigate the etiological factors (genetic vs. environmental) underlying the covariance between internalizing symptoms and cigarette use in adolescents.
• To determine if shared or additive genetic factors influence the co-occurrence of internalizing symptoms and cigarette use.

Main Methods:

• Utilized data from 1230 twin pairs in the Virginia Twin Study of Adolescent Behavioral Development.
• Employed variance decomposition models to analyze internalizing symptoms, cigarette initiation, and quantity smoked.
• Tested biometric models to differentiate genetic and environmental influences on the covariance.

Main Results:

• The covariance between internalizing symptoms and cigarette use in adolescents was primarily explained by sex-specific shared and unique environmental factors.
• Genetic factors did not significantly account for the overlap between internalizing symptoms and cigarette use.
• Environmental factors play a crucial role in the co-occurrence of these adolescent problems.

Conclusions:

• The association between internalizing symptoms and cigarette use in adolescents is attributable to non-genetic, environmental factors.
• Further research into specific environmental sources influencing adolescent internalizing symptoms and cigarette use is warranted.
• Environmental factors linking internalizing symptoms and cigarette use present potential targets for intervention.