Exercise Therapy to Treat Adults With Abdominal Aortic Aneurysms

AAAs are common among older individuals, and are the 10th leading cause of death for men
over the age of 55. A ruptured AAA usually leads to death. Therefore, early detection and
treatment are critical. Currently, there are several surgical treatment options available,
but there is no proven non-surgical treatment for AAAs. Research has shown that physical
inactivity may be linked to the development of AAAs. The purpose of this study is to gather
information on AAA risk factors, and to evaluate the effectiveness of an exercise program at
preventing the growth of small AAAs in older individuals.

This study will be composed of three individual projects. Project 1 will enroll 1400
individuals with small AAAs. Project 2 will enroll 1000 individuals with unknown aortic size
and previously tested exercise capacity. Both groups of participants will attend one study
visit, at which time their medical history and physical activity history will be recorded,
vital signs will be collected, and blood and urine sample will be given. Questionnaires
will be completed to document physical activity levels and AAA risk factors. An abdominal
ultrasound will be performed to measure the size of the aorta or AAA. Participants in
Project 2 will also take part in a treadmill exercise test, during which heart rate and
blood pressure will be recorded, and heart activity will be monitored by an
electrocardiogram (ECG).

The third project will last 3 years and will enroll 340 individuals from Project 1.
Participants will be randomly assigned to either an exercise program or a usual activity
group. An initial screening visit will include medical history review, vital sign
measurements, blood collection, questionnaires, an abdominal ultrasound, a positron emission
tomography (PET) scan, a computed tomography (CT) scan, and a magnetic resonance imaging
(MRI) scan.

Participants in the exercise program will complete an exercise test at the beginning of the
study and every 6 months for the duration of the study. Participants who live within 15
miles of the Palo Alto VA Hospital will take part in a supervised aerobic exercise program 3
days a week. Participants who live farther than 15 miles from the hospital will receive a
detailed exercise plan and will exercise on their own while wearing a heart rate and
activity tracking device. They will also attend monthly study visits for review of their
progress. All participants assigned to the exercise program will be encouraged to increase
their daily exercise. Each day they will wear a pedometer; twice a month they will wear a
global positioning system (GPS) and heart rate monitor. Participants assigned to the usual
activity group will wear pedometers each day and will maintain their usual level of physical
activity. At yearly study visits, blood will be collected and physical activity levels will
be assessed.

All Project 3 participants with AAAs smaller than 4 cm will undergo an ultrasound and blood
collection once a year; participants with AAAs 4 cm or larger will undergo the same
procedures every 6 months. At the end of 3 years, all participants will attend a final study
visit at which time their medical history will be reviewed and blood will be collected. They
will also undergo an abdominal ultrasound, and PET, CT, and MRI scans.

Inclusion Criteria:

- Small AAA less than 5.5 cm in size

- Over age 50

Exclusion Criteria:

- Patients with congenital aneurysm syndromes such as Ehlers-Danlos' or Marfan's