Effects of protein-enriched nutritional support on skeletal muscle mass and rehabilitative outcomes in brain tumor patients: a randomized controlled trial

Patients with brain tumors require extensive and prolonged rehabilitation efforts as they suffer from lesion-induced motor weakness as well as treatment-related side effects, often leading to a significant decline in function. Protein supplements have shown positive effects on promoting muscle strength and physical performance in various tumor etiologies. However, reports on their effects specifically in brain tumor patients remain scarce. This study aims to investigate the feasibility and efficacy of protein supplements in enhancing rehabilitative outcomes via muscle strengthening and functional gain in brain tumor patients with neurological demise. Sixty brain tumor patients were randomly assigned to either a protein supplement or a control group, receiving either protein supplements or a placebo for 6 weeks, in conjunction with conventional rehabilitation therapy. Assessments before and after the intervention included laboratory tests, anthropometric measures using bioimpedance analysis, and functional assessments, which included the MMSE, the modified Barthel Index, the Beck Depression Inventory, the Brief Fatigue Inventory, the Timed Up and Go test, the 6-min walk test, the isokinetic quadriceps muscle strength test, and the handgrip power. After the intervention, the levels of serum hemoglobin, protein, albumin, and C-reactive protein were improved in both groups, however, the change was significant only in the protein group. The muscle strength was enhanced in both groups, however, the significant increase in pinch grasp power was only noted in the protein group (P < 0.05). The distance on 6MWT was also significantly extended at follow-up in the protein group (P < 0.01). In the subgroup analysis according to nutritional status, the moderate malnutrition group showed greater augmentation of muscle mass than those with adequate nutrition (P < 0.05). Interestingly, the amelioration of malnutrition was observed only the in protein group. This study using protein supplements to promote the rehabilitative potential of brain tumor patients revealed a significant effect on improving hemodynamic nutritional indices, muscle power reimbursement, and functional improvement, especially in malnourished patients. The safety and feasibility of protein supplements in brain tumor patients were affirmative in this study. Further studies with more patients may help confirm the secondary functional gain resulting from increased muscle power. Trial registration: This study was retrospectively registered in the Clinical Research Information Service, CRIS no. KCT0009113 on Jan 12, 2024.