Effect of protein supplementation on fat-free mass among upper gastrointestinal surgical patients: A review of compliance

There is minimal data regarding the long-term effects of targeted daily protein intake and its role in nutritional restoration. This study aims to evaluate the effect of protein supplementation among upper gastrointestinal (GI) surgical patients, reviewing the effect on muscle mass and hand grip strength.The records of 223 upper GI surgical patients from September 2017 to June 2021 were retrospectively reviewed. Protein intake was categorised based on average daily protein intake (0.8g-1.2 g/kg/day vs. more than 1.2 g/kg/day), depending on compliance to the institution target of 1.2g-1.5 g/kg/day. Hand grip strength and body composition including weight, Body Mass Index (BMI), Fat-Free Mass (FFM), and Fat Mass (FM) were measured. Paired t-tests and independent t-tests were used to analyse the effects of different levels of protein intake on hand grip strength and body composition.Among the 223 patients included, 84 subjects had benign upper GI pathology and 139 subjects had malignant upper GI pathology, with mean follow-up duration of 52.3 (SD,42.10) weeks and 39.3 (SD,35.11) respectively. Patients with malignant pathology who consumed more than 1.2 g/kg/day of protein had increased hand-grip strength and preservation of FFM, while those who consumed 0.8g-1.2 g/kg/day of protein had deteriorating hand grip strength and significant FFM reduction (p = 0.004). Patients with benign pathology showed significant improvement in hand-grip strength (p < 0.001) and increase in FFM (p < 0.001) with higher protein intake.Protein supplementation is paramount in nutrition recovery and muscle mass restoration among upper gastrointestinal surgical patients. Protein intake of at least 1.2 g/kg/day was especially important among patients with malignancy to preserve muscle mass and strength.