Scientists have long observed a link between cigarette smoking
and depression, and questions over which causes which--or
whether both are caused by some third factor--have abounded. Now
a study in adolescents has found that heavy smoking and
depression affect each other reciprocally, creating a self-
perpetuating pattern of unhealthy behavior and negative effect.
In their research, psychologist Michael Windle, PhD, and
colleague Rebecca C. Windle, both of the University of Alabama
at Birmingham, studied 1,218 high school students for one and a
half years, beginning when the students were sophomores and
juniors. Every six months, students completed questionnaires
that assessed depression and cigarette smoking as well as
variables such as temperament, parents' smoking habits, social
support within the family, delinquent activity, alcohol and
other substance use, and friends' alcohol and drug use. The
results, published in the April Journal of Consulting and
Clinical Psychology (Vol. 69, No. 2), revealed that tee