METHODS/DESIGN: This open-labelled, randomised controlled trial (RCT) will randomly allocate patients into intervention and control groups. Ambulated Malaysian aged over 18 years and scheduled for elective surgery for (suspected) GC, will be included in this study. The intervention group will be given whey-protein-infused carbohydrate-loading drinks on the evening before their operation and 3 h before their operation as well as started on early oral feeding 4 h post-operatively. The control group will be fasted overnight pre-operation and only allowed plain water, and return to a normal diet is allowed when bowel sounds return post-operatively. The primary outcomes of study are length of post-operative hospital stay, length of clear-fluid tolerance, solid-food tolerance and bowel function. Additional outcome measures are changes in nutritional status, biochemical profile and functional status. Data will be analysed on an intention-to-treat basis.

METHODS: This multicenter, parallel, open-label, randomized controlled trial investigated the clinical efficacy of WPS in 126 malnourished CAPD patients with serum albumin <40 g/L and body mass index (BMI) <24 kg/m2. Patients randomized to the intervention group (IG, n = 65) received protein powder (27.4 g) for 6 months plus dietary counseling (DC) while the control group (CG, n = 61) received DC only. Anthropometry, biochemistry, malnutrition-inflammation-score (MIS), dietary intake inclusive of dialysate calories, handgrip strength (HGS) and quality of life (QOL) were assessed at baseline and 6 months. Clinical outcomes were assessed by effect size (Cohen's d) comparisons within and between groups.

RESULTS: Seventy-four patients (n = 37 per group) completed the study. Significantly more IG patients (59.5%) achieved dietary protein intake (DPI) adequacy of 1.2 g/kg per ideal body weight (p  0.05). A higher DPI paralleled significant increases in serum urea (mean Δ: IG = +2.39 ± 4.36 mmol/L, p = 0.002, d = 0.57 vs CG = -0.39 ± 4.59 mmol/L, p > 0.05, d = 0.07) and normalized protein catabolic rate, nPCR (mean Δ: IG = +0.11 ± 0.14 g/kg/day, p  0.05, d = 0.09) for IG compared to CG patients. Although not significant, comparison for changes in post-dialysis weight (mean Δ: +0.64 ± 1.16 kg vs +0.02 ± 1.36 kg, p = 0.076, d = 0.58) and mid-arm circumference (mean Δ: +0.29 ± 0.93 cm vs -0.12 ± 0.71 cm, p = 0.079, d = 0.24) indicated trends favoring IG vs CG. Other parameters remained unaffected by treatment comparisons. CG patients had a significant decline in QOL physical component (mean Δ = -6.62 ± 16.63, p = 0.020, d = 0.47). Using changes in nPCR level as a marker of WPS intake within IG, 'positive responders' achieved significant improvement in weight, BMI, skinfold measures and serum urea (all p  0.05).