Purpose

Obesity increases risk for all-cause and breast cancer mortality and comorbidities in women who have been diagnosed and treated for breast cancer. The Exercise and Nutrition to Enhance Recovery and Good Health for You (ENERGY) study is the largest weight loss intervention trial among survivors of breast cancer to date.

Methods

In this multicenter trial, 692 overweight/obese women who were, on average, 2 years since primary treatment for early-stage breast cancer were randomly assigned to either a group-based behavioral intervention, supplemented with telephone counseling and tailored newsletters, to support weight loss or a less intensive control intervention and observed for 2 years. Weight and blood pressure were measured at 6, 12, 18, and 24 months. Longitudinal mixed models were used to analyze change over time.

Results

At 12 months, mean weight loss was 6.0% of initial weight in the intervention group and 1.5% in the control group (P<.001). At 24 months, mean weight loss in the intervention and control groups was 3.7% and 1.3%, respectively (P<.001). Favorable effects of the intervention on physical activity and blood pressure were observed. The weight loss intervention was more effective among women older than 55 years than among younger women.

Conclusion

A behavioral weight loss intervention can lead to clinically meaningful weight loss in overweight/obese survivors of breast cancer. These findings support the need to conduct additional studies to test methods that support sustained weight loss and to examine the potential benefit of intentional weight loss on breast cancer recurrence and survival.

Purpose

Comorbid medical conditions are common among breast cancer survivors, contribute to poorer long-term survival and increased overall mortality, and may be ameliorated by weight loss. This secondary analysis evaluated the impact of a weight loss intervention on comorbid medical conditions immediately following an intervention (12 months) and 1-year postintervention (24 months) using data from the Exercise and Nutrition to Enhance Recovery and Good health for You (ENERGY) trial-a phase III trial which was aimed at and successfully promoted weight loss.

Methods

ENERGY randomized 692 overweight/obese women who had completed treatment for early stage breast cancer to either a 1-year group-based behavioral intervention designed to achieve and maintain weight loss or to a less intensive control intervention. Minimal support was provided postintervention. New medical conditions, medical conditions in which non-cancer medications were prescribed, hospitalizations, and emergency room visits, were compared at baseline, year 1, and year 2. Changes over time were analyzed using chi-squared tests, Kaplan-Meier, and logistic regression analyses.

Results

At 12 months, women randomized to the intervention had fewer new medical conditions compared to the control group (19.6 vs. 32.2 %, p < 0.001); however, by 24 months, there was no longer a significant difference. No difference was observed in each of the four conditions for which non-cancer medications were prescribed, hospital visits, or emergency visits at either 12 or 24 months.

Conclusions

These results support a short-term benefit of modest weight loss on the likelihood of comorbid conditions; however, recidivism and weight regain likely explain no benefit at 1-year postintervention follow-up.