Total energy expenditure assessed by 24-h whole-room indirect calorimeter in patients with colorectal cancer: baseline findings from the PRIMe study.

BACKGROUND: Total energy expenditure (TEE) determines energy requirements, but objective data in patients with cancer are limited. OBJECTIVES: We aimed to characterize TEE, investigate its predictors, and compare TEE with cancer-specific predicted energy requirements. METHODS: This cross-sectional analysis included patients with stages II-IV colorectal cancer from the Protein Recommendation to Increase Muscle (PRIMe) trial. TEE was assessed by 24-h stay in a whole-room indirect calorimeter before dietary intervention and compared with cancer-specific predicted energy requirements (25-30 kcal/kg). Generalized linear models, paired-samples t tests, and Pearson correlation were applied. RESULTS: Thirty-one patients (56 ± 10 y; body mass index [BMI]: 27.9 ± 5.5 kg/m2; 68% male) were included. Absolute TEE was higher in males (mean difference: 391 kcal/d; 95% CI: 167, 616 kcal/d; P < 0.001), patients with colon cancer (mean difference: 279 kcal/d; 95% CI: 73, 485 kcal/d; P = 0.010), and patients with obesity (mean difference: 393 kcal/d; 95% CI: 182, 604 kcal/d; P < 0.001). Appendicular lean soft tissue (ß: 46.72; 95% CI: 34.27, 59.17; P < 0.001) and tumor location (colon-ß: 139.69; 95% CI: 19.44, 259.95; P = 0.023) independently predicted TEE when adjusted for sex. Error between measured TEE and energy requirements predicted by 25 kcal/kg (mean difference: 241 kcal/d; 95% CI: 76, 405 kcal/d; P = 0.010) or 30 kcal/kg (mean difference: 367 kcal/d; 95% CI: 163, 571 kcal/d; P < 0.001) was higher for patients with obesity, and proportional error was observed (25 kcal/kg: r = -0.587; P < 0.001; and 30 kcal/kg: r = -0.751; P < 0.001). TEE (mean difference: 25 kcal/kg; 95% CI: 24, 27 kcal/kg) was below predicted requirements using 30 kcal/kg (-430 ± 322 kcal/d; P < 0.001). CONCLUSIONS: This is the largest study to assess TEE of patients with cancer using whole-room indirect calorimeter and highlights the need for improved assessment of energy requirements in this population. Energy requirements predicted using 30 kcal/kg overestimated TEE by 1.44 times in a controlled sedentary environment and TEE was outside of the predicted requirement range for most. Special considerations are warranted when determining TEE of patients with colorectal cancer, such as BMI, body composition, and tumor location. This is a baseline cross-sectional analysis from a clinical trial registered at clinicaltrials.gov as NCT02788955 (https://clinicaltrials.gov/ct2/show/NCT02788955).

Protein Recommendation to Increase Muscle (PRIMe): Study protocol for a randomized controlled pilot trial investigating the feasibility of a high protein diet to halt loss of muscle mass in patients with colorectal cancer.

BACKGROUND: Severe muscle mass (MM) loss is a defining feature of cancer observed across all types and stages of disease and is an independent predictor of poor clinical outcomes including higher incidences of chemotherapy toxicity and decreased survival. Protein is essential to build MM, yet the optimal amount for preventing or treating muscle loss in patients with cancer remains undefined. METHODS: The Protein Recommendation to Increase Muscle (PRIMe) study is a single-center, two-armed, parallel, randomized, controlled pilot trial that assesses the feasibility of utilizing a high protein (HP) diet to positively impact clinical outcomes in people undergoing chemotherapy to treat colorectal cancer. Forty patients with newly diagnosed stage II-IV colorectal cancer who are scheduled to receive chemotherapy will be included. Participants are randomly assigned to a HP or normal protein (NP) diet for twelve weeks. The HP and NP groups receive nutrition recommendations to achieve 2.0 g of protein per kilogram of body weight per day (g∙kg-1∙d-1) and 1.0 g⋅kg-1⋅d-1, respectively. These values refer to the upper and lower recommended range of protein intake for people with cancer. Energy recommendations are based on measured energy expenditure. Assessments are completed within two weeks of starting chemotherapy (baseline), at week 6, and at week 12. Changes to skeletal MM, physical function, anthropometrics, body composition, muscle strength, physical activity, energy metabolism, metabolic markers, nutritional status, quality of life, readiness to change and psychosocial determinants of behavioural change are assessed between the HP and NP groups. Feasibility of the nutritional intervention is assessed by change in MM as a surrogate marker. CONCLUSIONS: This evidence-based study investigates the feasibility of increasing protein intake following a diagnosis of cancer on clinical outcomes during treatment for colorectal cancer. This study will inform larger trials assessing the impact of increasing protein intake in cancer to determine their importance and integration into standard clinical care for people with cancer.