Depression Outcomes Study of Exercise

Adolescent depression is a major public health problem in the United States and throughout
the world. Major depressive disorder (MDD) in adolescence is common with point prevalence
rates of 3% to 9%. In the U.S., it is estimated that by the time adolescents reach the age
of 17, 14% will have experienced at least one episode of major depressive disorder.
Effective treatments of adolescent depression are clearly needed despite the fact that in
the past 10-15 years, there has been a dramatic increase in studies of the efficacy of
medications, primarily the selective serotonin reuptake inhibitors (SSRIs) and of cognitive
behavioral therapy (CBT). Medications and CBT rarely result in complete and lasting
remission of symptoms, and residual symptoms are associated with a high rate of relapse. In
most studies, a positive response is defined as a 30-50% improvement in symptoms and/or a
global rating that the subject is much or very much improved. In adults, exercise has been
used as a mono-therapy and as an augmentation therapy with antidepressant medication. Our
recently completed randomized trial of exercise treatment in adults found response and
remission rates of 46% and 42%, in those randomized to a public health dose of exercise. In
adolescents, data on the use of exercise to treat MDD is relatively sparse. A 2006 Cochrane
review of exercise to prevent and treat depression in adolescents found a small effect size
in support of exercise, but the conclusion is based on evidence from a small number of
randomized clinical trials of low methodological quality. In this exploratory R34, the
specific aims of this application are to: 1) Develop a detailed Manual of Procedures (MOP)
to conduct an acute-phase randomized trial of exercise to treat adolescent depression; 2)
Develop estimates of recruitment yield from tests of various recruitment strategies; and, 3)
Pilot test trial methodologies in (n=40) adolescents diagnosed with depression to ascertain
estimates of treatment effect sizes, adherence and drop-out rates. To achieve these aims,
the project is organized into 3 phases. Phase I will be the development of the first draft
MOP that will adapt procedures developed from a previous trial examining two doses of
exercise in treatment of adult MDD. Phase II will test specific recruitment methodologies to
determine recruitment yields for each strategy and will pilot test screening procedures
developed in Phase I. Phase III will be a pilot test of the intervention and will include
development of baseline and outcome measures of exercise and depression; development and
implementation of the experimental exercise treatment; and determination of the effects of
exercise on depressive symptoms. Following the pilot study, we will finalize all procedures
for the MOP and obtain estimates of effect sizes, adherence and drop out rates. These data
will allow us to specify all study procedures necessary to meet standards of high
methodological quality for a future, larger-scale, controlled study of exercise in depressed
youth and will provide us with needed experience.

Inclusion Criteria:

- Primary Diagnosis of DSM-IV Major Depression Disorder (MDD)

- Child Depression Rating Scale Revised > or = 40 at final screen

- 12 to 21 years of age

- On a stable dose of antidepressants or ADHD medication only

- Physically capable of exercise according to AHA and ACSM standards

- Able to pass illicit drug screen

- Perform < 20 minutes per day of moderate to vigorous physical activity

- Parental consent and participant assent

- Denver metropolitan area including Jefferson county

Exclusion Criteria:

- Chronic disease that would limit exercise

- Other psychiatric illness

- Suicidal or homicidal

- Concurrent psychotherapy

- Two previous failed SSRI trials or a failed trial of CBT

- Current pregnancy or breastfeeding