The effectiveness of a targeted education intervention to increase protein intake in people with CHD: a pilot feasibility randomised controlled trial

Low protein intake is prevalent in people with CHD and is inadequately addressed in UK-based cardiac rehabilitation. This pilot feasibility study aimed to identify whether targeted education increases protein intake in patients with CHD and low protein intake, compared with standard cardiac rehabilitation dietary education. People referred to cardiac rehabilitation with CHD (≥ 50 years) underwent anthropometric assessment and completed a food diary, sit-to-stand test and three questionnaires (physical activity, sarcopenia screening and nutrition knowledge). Participants with low protein intake (≤ 1·2 g/kg per d) were randomised to receive either extra protein education (intervention; protein group) or standard education (control; control group), embedded within their usual 6-week cardiac rehabilitation programme. At 6 and 12 weeks, outcome measures were repeated; thirty-four participants provided baseline data. Protein intake was inversely associated with waist circumference (r = −0·348). Twenty-seven participants (79 %) with low protein intake were randomised to the protein group (n 15) or control group (n 12). At week 6, the median (interquartile range) change in protein intake was 0·0 (−0·0–0·3) and 0·4 (0·2–0·5) g/kg per d in the protein group and control group, respectively (effect size 0·5). At week 12, the change in protein intake was 0·0 (−0·0–0·1) and −0·0 (−0·2–0·2) g/kg per d in the protein group and control group, respectively (effect size 0·3). Effect sizes for all other variables were ≤ 0·4. The intervention appeared well-received by those who completed the study; however, changes to primary and secondary outcomes were minimal. Uptake of the study was low, and attrition was high, limiting the interpretation of efficacy and the implementation of a definitive trial.