Effects of an exercise-based oncology rehabilitation program and age on strength and physical function in cancer survivors.

PURPOSE: Cancer therapy diminishes strength and physical function in cancer survivors. Whether oncology rehabilitation (OR) exercise training following therapy can correct these deficits, and whether its effectiveness differs by age, is not clear. We examine the utility of a clinically based, 12-week, combined aerobic and resistance training intervention on muscle strength and physical function in two age groups of cancer survivors. METHODS: Strength and physical function measures were assessed in middle-aged (45 to 64 years) and older (≥ 65 years) patients following treatment for stage 0-III cancer before and after the OR training program. RESULTS: Older patients had lower physical function compared to middle-aged patients across a range of subjective and objective measures at baseline, and exercise improved all indices of physical function and strength in both age groups. Compared to the middle-aged individuals, older participants tended to have less improvement leg strength and the 5 time sit to stand (5TSTS) test as a result of OR. In models predicting post-intervention measures, older age contributed to less improvement in walking distance and power as well as the 5TSTS test. CONCLUSION: Prior to beginning the OR exercise program, middle-aged patients had higher physical function compared to older patients. However, a 12-week aerobic and resistance training intervention improved physical function across both age groups, although older age did limit responsiveness in some physical function measures. The physical function and strength of middle-aged and older cancer survivors improve in response to an exercise-based OR program after cancer treatment.

Impact of a behaviorally-based weight loss intervention on parameters of insulin resistance in breast cancer survivors.

BACKGROUND: Breast cancer survivors with excess weight are more likely to have negative breast cancer outcomes. Biomarkers related to insulin resistance may help explain this negative association. Weight loss is associated with improvements in insulin sensitivity. Our goal was to identify the impact of a behaviorally based weight loss intervention on indices of insulin resistance. METHODS: Overweight, early stage breast cancer survivors who completed initial cancer therapy were enrolled in a 6 month behaviorally based weight loss intervention that included calorie reduction, exercise and behavior modification. Biomarkers related to insulin resistance were obtained at baseline and after the intervention. Results from participants who achieved ≥5% weight loss were compared to those who lost less weight. RESULTS: Despite not having diabetes as a preexisting diagnosis prior to the study, 69% of all participants were considered to have pre-diabetes or diabetes at baseline based on American Diabetes Association definitions. Participants who achieved ≥5% weight loss had significantly lower fasting insulin, AUC insulin, and insulin resistance as measured by HOMA-IR. Beta cell function decreased as anticipated when insulin resistance improved. Additionally, leptin levels declined. CONCLUSIONS: Breast cancer survivors who achieved ≥5% weight loss demonstrated significant improvements in indices of insulin resistance. Despite an exclusion criteria of diabetes at the time of enrolment, a high proportion met criteria for pre-diabetes or diabetes at baseline. Pre-diabetes appears to be under recognized in overweight breast cancer survivors. Behaviorally based weight loss interventions can result in weight loss and improvements in biomarkers related to breast cancer outcomes and additionally may decrease the chance of developing diabetes. TRIAL REGISTRATION: NCT01482702 4/12/2010 (retrospectively registered).  https://clinicaltrials.gov/ct2/show/NCT01482702?term=Dittus&rank=4.

Body composition in amyotrophic lateral sclerosis subjects and its effect on disease progression and survival.

BACKGROUND: Motor neuron degeneration and malnutrition alter body composition in amyotrophic lateral sclerosis (ALS). Resulting losses of weight, fat mass (FM), and fat-free mass (FFM) shorten survival. Nutritional management relies on body weight or BMI; neither reliably indicates malnutrition nor differentiates body compartments. OBJECTIVES: We aimed to 1) develop an equation to compute FM and FFM using clinical data, validated against DXA; and 2) examine the effect of computed FM and FFM on disease course and survival. METHODS: We studied 364 ALS patients from 3 cohorts. In Cohort #1 we used logistic regression on clinical and demographic data to create an equation (test cohort). In Cohort #2 we validated FM and FFM computed using this equation against DXA (validation cohort). In Cohort #3, we examined the effect of computed body composition on disease course and survival. RESULTS: In Cohort #1 (n = 29) the model incorporated sex, age, BMI, and bulbar-onset to create an equation to estimate body fat: % body fat = 1.73 - [19.80*gender (1 if male or 0 if female)] + [0.25*weight (kg)] + [0.95*BMI (kg/m2)] - (5.20*1 if bulbar-onset or *0 if limb-onset). In Cohort #2 (n = 104), body composition using this equation, compared to other published equations, showed the least variance from DXA values. In Cohort #3 (n = 314), loss of body composition over 6 mo was greater in males. Adjusted survival was predicted by low baseline FM (HR: 1.39; 95% CI: 1.07, 1.80), and loss of FM (HR: 1.87; 95% CI: 1.30, 2.69) and FFM (HR: 1.73; 95% CI: 1.20, 2.49) over 6 mo. CONCLUSIONS: Our equation broadens the traditional nutritional evaluation in clinics and reliably estimates body composition. Measuring body composition could target FM as a focus for nutritional management to ensure adequate energy intake and complement measures, such as the ALS functional rating scale-revised score and forced vital capacity, currently used.

Exercise-based oncology rehabilitation: leveraging the cardiac rehabilitation model.

PURPOSE: The value of exercise and rehabilitative interventions for cancer survivors is increasingly clear, and oncology rehabilitation programs could provide these important interventions. However, a pathway to create oncology rehabilitation has not been delineated. Community-based cardiac rehabilitation (CR) programs staffed by health care professionals with experience in providing rehabilitation and secondary prevention services to individuals with coronary heart disease are widely available and provide a potential model and location for oncology rehabilitation programs. Our purpose was to outline the rehabilitative needs of cancer survivors and demonstrate how oncology rehabilitation can be created using a CR model. METHODS: We identify the impairments associated with cancer and its therapy that respond to rehabilitative interventions. Components of the CR model that would benefit cancer survivors are described. An example of an oncology rehabilitation program using a CR model is presented. RESULTS: Cancer survivors have impairments associated with cancer and its therapy that improve with rehabilitation. Our experience demonstrates that effective rehabilitation services can be provided utilizing an existing CR infrastructure. Few adjustments to current CR models would be needed to provide oncology rehabilitation. Preliminary evidence suggests that cancer survivors participating in an oncology rehabilitation program experience improvements in psychological and physiologic parameters. CONCLUSIONS: Utilizing the CR model of rehabilitative services and disease management provides a much needed mechanism to bring oncology rehabilitation to larger numbers of cancer survivors.