Randomized Trial Evaluating a Self-Guided Lifestyle Intervention Delivered via Evidence-Based Materials versus a Waitlist Group on Changes in Body Weight, Diet Quality, Physical Activity, and Quality of Life among Breast Cancer Survivors

SIMPLE SUMMARY: While resource-intensive lifestyle interventions for breast cancer survivors have proved effective at stimulating positive behavior change and promoting healthy weight loss, integrating these programs into clinical practice is challenging. To address these challenges, we adapted our supervised in-person/telephone Lifestyle, Exercise and Nutrition (LEAN) lifestyle program for breast cancer survivors with overweight or obesity to a 6-month, unsupervised, self-guided program, delivered via printed materials and online videos. We tested the efficacy of the LEAN Self-Guided program on weight loss, diet quality, physical activity, and quality of life. At 6 months, the intervention arm had significantly greater weight loss compared with the waitlist group (mean difference = −1.3 kg, 95% confidence interval [CI] = −2.5, −0.13) and maintained this weight loss from 6 months to 12 months (−0.21 kg; p = 0.75). Low-resource-intensive programs have the potential to be delivered in diverse healthcare settings and may support breast cancer survivors in achieving a healthy body weight. ABSTRACT: Background: Lifestyle interventions for breast cancer survivors have proved effective at stimulating positive behavior change and promoting healthy weight loss, although integrating these programs into clinical practice is challenging. We evaluated the effect of a 6-month, unsupervised, self-guided, lifestyle intervention using printed materials and online videos vs. waitlist group on body weight for breast cancer survivors. Methods: The Lifestyle, Exercise and Nutrition (LEAN) Self-Guided trial randomized breast cancer survivors with a body mass index ≥25 kg/m(2) to a 6-month lifestyle intervention (N = 102) or waitlist group (N = 103). Effects of the intervention on self-reported body weight, physical activity (PA), diet quality (via Health Eating Index—2010 (HEI-2010)), and quality of life were assessed using mixed model repeated measures analysis. Results: At 6 months, the intervention arm had significantly greater weight loss compared with the waitlist group (mean difference = −1.3 kg, 95% confidence interval [CI] = −2.5, −0.13). We observed suggestive improvements in PA (mean difference = 18.7 min/week, 95% CI = −24.2, 61.6), diet quality (mean difference in HEI = 3.2 points, 95% CI = −0.20, 6.5), and fatigue (mean difference in Functional Assessment of Chronic Illness Therapy—Fatigue scale = 1.4 points, 95% CI = −1.1, 3.9). Conclusions: The LEAN Self-Guided intervention led to favorable weight changes over 6 months. Low-resource-intensive programs have the potential to be delivered in diverse healthcare settings and may support breast cancer survivors in achieving a healthy body weight.