The Alberta Physical Activity and Breast Cancer Prevention Trial: quality of life outcomes.

OBJECTIVE: Interventions for disease prevention should also be evaluated for quality of life (QoL) effects. Few exercise trials have examined QoL in the context of primary disease prevention. Here, we report the QoL outcomes from the Alberta Physical Activity and Breast Cancer Prevention (ALPHA) Trial. METHODS: The ALPHA trial was a randomized controlled trial in Calgary and Edmonton, Canada between May 2003 and July 2007 that compared an exercise intervention to a sedentary lifestyle among 320 sedentary, postmenopausal women. The exercise group was asked to perform moderate-to-vigorous intensity aerobic exercise 45 min/day, 5 days/week for 1 year. QoL was assessed by the short form-36 health survey. RESULTS: Compared to the control group, the exercise group maintained significantly better physical functioning (p<0.001), general health (p<0.001), vitality (p=0.002), and bodily pain (p=0.020) by 4-5 points which exceeds the 3.0 minimally important difference for these scales. Changes in body composition partially mediated the intervention effects. Antidepressant use and the presence of comorbidities moderated some intervention effects. CONCLUSIONS: A 1-year moderate-to-vigorous aerobic exercise program prevents declines in the physical aspects of QoL in postmenopausal women. Exercise may have a potentially important advantage for breast cancer prevention compared to other lifestyle or biomedical interventions.

Associations between mammographic density and serum and dietary cholesterol.

Although high mammographic density is a risk factor for postmenopausal breast cancer, its etiology remains unclear. We examined whether serum and dietary cholesterol, which increase breast cancer risk and are involved in endogenous estrogen formation, were associated with increased mammographic density. We conducted a cross-sectional analysis of 302 healthy, sedentary postmenopausal women, aged 50-74 years, enrolled in the Alberta Physical Activity and Breast Cancer Prevention Trial between 2003 and 2006. In multiple linear regression models, no significant associations were observed between serum lipids and percent density or dense tissue area (Percent density: b (change in square root percent density per unit change in cholesterol level) = -0.06 (95%CI = -0.26 to 0.13); b = 0.06 (95%CI = -0.48 to 0.61); and b = -0.11 (95%CI = -0.33 to 0.10) for total cholesterol, high-, and low-density lipoprotein, respectively; similar results found for dense area). Alcohol consumption modified the association between triglycerides and percent density (>1 drink/day: b = -0.94 (95%CI = -1.79 to -0.10); ≤ 1 drink/day: b = 0.19 (95%CI = -0.12 to 0.50); and no alcohol consumption: b = 0.15 (95%CI = -0.44 to 0.73). We found no evidence indicating any association between dietary and serum cholesterol levels and mammographic density.