Impact of adherence to oral nutritional supplements on nutrition status and muscle strength in patients with gastrointestinal cancer: A prospective observational longitudinal study.

Background: Given the lack of evidence regarding the effects of adherence to oral nutritional supplements (ONS) and the types of formulas used in clinical practice, we aimed to assess the impact of adherence to ONS and the high-protein formula on the nutrition status and muscle strength in patients with gastrointestinal cancer.

Methods: This study evaluated newly diagnosed outpatients with esophageal, gastric, pancreatic, and colorectal cancer prescribed ONS. Nutrition status was assessed using the Patient-Generated Subjective Global Assessment (PG-SGA), and muscle strength was assessed using handgrip strength (HGS) dynamometry. ONS adherence was calculated as the ratio of self-reported intake to the prescribed amount and categorized as ≥80% or <80%.

Results: A total of 54 patients were included. Most patients were ≥60 years of age (63%), were diagnosed with colorectal cancer (63%), were classified as stage III and IV (83%), and exhibited nutrition risk or malnutrition according to PG-SGA (89%). Patients with adherence ≥80% to ONS exhibited less weight loss and HGS reduction compared with patients with adherence <80% (P < 0.05). Although patients consuming a high-protein formula maintained HGS and those on a standard formula experienced a reduction, formula type did not predict HGS change in the multivariate analysis. ONS protein intake, adjusted for adherence, was a predictor of weight change (β: 0.09; 95% CI: 0.02-0.2; P = 0.011).

Conclusion: Patients with adherence ≥80% to ONS experienced less reduction in both weight and HGS, whereas those consuming a high-protein formula maintained HGS. Notably, ONS protein intake, adjusted for adherence, was an independent predictor of weight change.