Weight Reduction Intervention for Breast Cancer Survivors
Condition: Breast Cancer
MeSH terms: Breast Neoplasms
Study type: Interventional

Summary: 
      Overweight or obesity is an established negative prognostic factor in both premenopausal and
      postmenopausal breast cancer. Several mechanisms have been proposed to explain the adverse
      effect of excess body fat on prognosis following the diagnosis of breast cancer, including
      increased circulating sex hormones, insulin, leptin, and various growth factors. Results from
      previous studies suggest that specific strategies can facilitate weight reduction and
      maintenance of weight loss in this target population. This randomized clinical trial will
      recruit 253 overweight or obese women who have been previously treated for early stage breast
      cancer and will test whether a multifaceted approach to promoting healthy weight management
      can achieve the goal of weight loss and maintenance. Additionally, this study tests whether
      weight loss is associated with changes in biological and psychosocial factors, including
      eating attitudes and behaviors and health-related quality of life. The intervention
      incorporates cognitive-behavioral therapy, increased physical activity, diet modification to
      facilitate a modest reduction in energy intake, and strategies to improve body image and
      self-acceptance. This approach and intervention have been pilot-tested with breast cancer
      survivors in a developmental project, which resulted in the intervention group losing
      significantly more weight than the wait-list control group.

      Study Aims include: testing whether an intervention that emphasizes increased physical
      activity and individualized diet modification to promote an energy imbalance is associated
      with a greater degree of weight loss and maintenance of that loss over an 18-month time
      period; describing the effect of the intervention on hormones and growth factors; describing
      the relationships between body weight and weight reduction and measures of selected
      psychosocial factors. Measurements of hormonal and psychosocial factors in this study will
      provide insight into the responsiveness of these factors to weight loss in overweight or
      obese breast cancer survivors, which will provide an indication of the degree of clinical
      benefit that is achieved with the intervention efforts. Results from this study may enable
      the development of broader efforts transferable to clinical practice and public health, and
      thus, may ultimately have a substantial effect on the risk for recurrence and long-term
      survival of the estimated 1.98 million breast cancer survivors in the U.S. today.
    

Detailed description: 
      Background: Overweight or obesity is an established negative prognostic factor in both
      premenopausal and postmenopausal breast cancer. Adverse effects of adiposity on prognosis may
      be explained by effects on gonadal hormones, insulin, insulin-like growth factor (IGF)-I, IGF
      binding proteins (IGFBPs), and leptin.

      Objective/Hypothesis: This study tests whether a multifaceted approach can achieve weight
      loss and maintenance in overweight or obese breast cancer survivors. The intervention
      incorporates cognitive-behavioral therapy, increased physical activity, diet modification,
      and strategies to improve body image and self-acceptance. This approach and intervention were
      developed and pilot-tested with support from a previous peer-reviewed grant. Weight change
      from baseline to one year in the pilot study (n=85) was -5.2 (6.3) kg (mean [SD]) in the
      intervention group vs. -0.1 (6.5) kg in the control group (P < 0.05), using intent to treat
      analysis with baseline values carried forward for dropouts.

      Specific aims: (1) To test whether the intervention promotes weight loss and maintenance of
      that loss over an 18-month time period in a larger group; (2) To describe the effect of the
      intervention on hormonal factors (insulin, leptin, IGF-I, IGFBP-1, IGFBP-3, sex-hormone
      binding globulin, and serum estrogens); and (3) To describe the relationships between body
      weight and weight reduction and measures of psychosocial factors (health-related quality of
      life, fatigue, depression, eating attitudes, and weight and shape concerns).

      Study design: The study targets 253 overweight or obese women previously treated for early
      stage breast cancer and utilizes a randomized study design with subjects assigned to the
      group-based healthy weight management program (with individualized telephone counseling
      support) or a wait-list control group. Data collection includes anthropometric and
      psychosocial measures, body composition (dual-energy x-ray absorptiometry), cardiopulmonary
      fitness testing, and hormonal measures at baseline and six and 18 months.
    

Intervention name(s): Cognitive behavioral therapy CBT) for weight loss
Intervention type(s): Behavioral
Intervention description(s): The intervention program emphasizes regular physical activity, healthy eating, and psychological components within the structure of CBT for obesity. The physical activity component emphasizes planned aerobic exercise, increased physical activity and strength training. A deficit of 500-1000 kcal/day is the recommended level of dietary modification to promote weight loss and maintenance. Group sessions are held weekly for 4 months, every other week for two months, and monthly sessions through 18 months. Data are collected at baseline, 6 months, and 18 months. Wait-list group subjects will receive general contact without specific reference to weight management topics through a 24-month period of data collection and will then be provided intervention materials in a seminar format.
Allocation: Randomized
Intervention model: Parallel Assignment
Intervention model description: Weight list control group was the comparison to the immediate treatment group.
Masking: None (Open Label)
Primary purpose: Prevention
Keywords: Overweight; Obese; Breast cancer survivors; Weight loss; Physical activity; Exercise; Cognitive behavioral therapy