Effects of creatine supplementation on nutritional status, muscle function and quality of life in patients with colorectal cancer--a double blind randomised controlled trial.

BACKGROUND & AIM: Nutritional status frequently deteriorates during chemotherapy in cancer. This is associated with a poor outcome. Since creatine supplementation has shown promising results in various diseases, we investigated the effects of creatine on nutritional status in patients with colorectal cancer undergoing chemotherapy. METHODS: Thirty patients with colorectal cancer undergoing chemotherapy were randomised to receive either creatine (n=16) or placebo (n=15) for 8 weeks. Body composition was determined with bioelectrical impedance analysis; muscle function by hand grip, hip flexion and knee extension strength and quality of life (QoL) was assessed by the QLQ30 questionnaire. RESULTS: Neither muscle function, body cell mass (BCM) nor QoL improved, but phase angle, a marker of BCM and cell integrity, increased significantly in the intervention patients (5.3+/-0.3 degrees to 5.4+/-0.2 degrees , P=0.030). Evaluating patients with different chemotherapy regimens, however, only intervention patients undergoing less aggressive chemotherapy were shown to benefit, increasing phase angle (5.11+/-0.22 degrees to 5.51+/-0.30 degrees , P=0.043) as well as BCM (27.22+/-2.85 to 29.60+/-3.54kg, P=0.043). CONCLUSION: Creatine failed to improve muscle mass or function and QoL in colorectal cancer patients but improved bioimpedance parameters that are predictive of poor outcome. Creatine might therefore be useful in patients with milder chemotherapy in order to maintain or increase BCM whereas patients undergoing aggressive chemotherapy however are not likely to benefit.