Alberta Physical Activity and Breast Cancer Prevention (ALPHA) Trial

AHS Cancer Control Alberta

Status: Completed

Conditions: Breast Neoplasms

Treatments: Behavioral: Aerobic exercise intervention

Study type: Interventional

Funder types: Other

Identifiers

NCT00522262

16649

Details and patient eligibility

About

The purpose of the ALPHA Trial is to examine the physiologic changes that occur in a woman's body when she begins exercising that may be related to a change in her risk of getting breast cancer.

Full description

The goal of this study is to examine how a one-year exercise intervention, as compared to a usual sedentary lifestyle, influences specific biologic mechanisms that are hypothesized to be operative in the association between physical activity and breast cancer risk. These biologic mechanisms include sex hormone concentrations (estrone, estradiol and sex-hormone binding globulin); measures of adiposity and obesity; mammographic density; insulin-like growth factors; and insulin resistance.

A two-centered, two-armed randomized controlled trial (RCT) of exercise and risk factors for breast cancer will be conducted. Approximately 334 postmenopausal, sedentary women will be recruited to the study. Participants will be randomized to one of two groups: an exercise intervention, or a control group. The intervention group will undertake five weekly exercise sessions of 60 minutes each; three will be facility-based and two will be home-based each week. The Edmonton and Calgary exercise oncology facilities will be working in collaboration, and each will include both the controls and exercise intervention arms of the trial. The exercise intervention will last for 12 months. The control group will be asked not to change their usual level of activity during that time.

Baseline assessments will be obtained of serum sex hormones (estrone and estradiol), measures of obesity and adiposity, mammographic density, serum insulin growth factor (IGF)-1, insulin resistance, aerobic capacity, and psychosocial health measures. At the end of the study, all baseline assessments will be repeated and compared between the two groups.

This study will specifically address identified gaps in knowledge, in terms of examining the simultaneous effect of physical activity on several biologic mechanisms in a controlled trial setting, building on evidence from the only other randomized controlled trial on this topic. Strengths of the proposal include the multi-centered setting (utilizing facilities in both Calgary and Edmonton), and the collaboration of an experienced multi-disciplinary research team from across North America.

Enrollment: 320 patients

Sex: Female

Ages: 50 to 74 years old

Volunteers: Accepts Healthy Volunteers

Inclusion criteria

• Female
• Age 50-74 at baseline
• Postmenopausal
• Moderately sedentary lifestyle
• Live in Calgary or Edmonton, Alberta, Canada
• English-speaking
• Willing to be randomized
• Body-mass index 22.0-40.0
• Breast tissue density >=0%

Exclusion criteria

• Previous invasive cancer in last 5 years
• Major co-morbidities
• Unable to participate in exercise program
• Current smoker
• Current excessive drinker
• Hormone replacement therapy use in previous 2 years
• Drugs that may influence one or more study outcomes

Trial design

Primary purpose: Prevention

Allocation: Randomized

Interventional model: Parallel Assignment

Masking: None (Open label)

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320 participants in 2 patient groups

Exercise

Experimental group

Description:

Women randomized to the exercise intervention arm completed a one year aerobic exercise intervention of 225 minutes/week.

Treatment:

Behavioral: Aerobic exercise intervention

Control

No Intervention group

Description:

Women randomized to the control arm were asked to maintain their regular lifestyle which meant no changes to their exercise or dietary intake. Women eligible for this trial were inactive and hence were expected not to increase their levels of physical activity in the control arm.