Greater survival after breast cancer in physically active women with high vegetable fruit intake regardless of obesity.
PURPOSE Single variable analyses have associated physical activity, diet, and obesity with survival after breast cancer. This report investigates interactions among these variables. PATIENTS AND METHODS A prospective study was performed of 1,490 women diagnosed and treated for early stage breast cancer between 1991 and 2000. Enrollment was an average of 2 years postdiagnosis. Only seven women were lost to follow up through December 2005. RESULTS In univariate analysis, reduced mortality was weakly associated with higher vegetable fruit consumption, increased physical activity, and a body mass index that was neither low weight nor obese. In a multivariate Cox model, only the combination of consuming five or more daily servings of vegetables fruits, and accumulating 540+ metabolic equivalent tasks min/wk (equivalent to walking 30 minutes 6 d/wk) was associated with a significant survival advantage (hazard ratio, 0.56; 95% CI, 0.31 to 0.98) The approximate 50% reduction in risk associated with these healthy lifestyle behaviors was observed in both obese and nonobese women, although fewer obese women were physically active with a healthy dietary pattern (16% v 30% Among those who adhered to this healthy lifestyle, there was no apparent effect of obesity on survival. The effect was stronger in women who had hormone receptor positive cancers. CONCLUSION A minority of breast cancer survivors follow a healthy lifestyle that includes both recommended intakes of vegetables fruits and moderate levels of physical activity. The strong protective effect observed suggests a need for additional investigation of the effect of the combined influence of diet and physical activity on breast cancer survival.
Journal of clinical oncology official journal of the American Society of Clinical Oncology