Systematic review and meta-analysis of the effects of high protein oral nutritional supplements.

Disease-related malnutrition is common, detrimentally affecting the patient and healthcare economy. Although use of high protein oral nutritional supplements (ONS) has been recommended to counteract the catabolic effects of disease and to facilitate recovery from illness, there is a lack of systematically obtained evidence to support these recommendations. This systematic review involving 36 randomised controlled trials (RCT) (n=3790) (mean age 74 years; 83% of trials in patients >65 years) and a series of meta-analyses of high protein ONS (>20% energy from protein) demonstrated a range of effects across settings and patient groups in favour of the high protein ONS group. These included reduced complications (odds ratio (OR) 0.68 (95%CI 0.55-0.83), p<0.001, 10 RCT, n=1830); reduced readmissions to hospital (OR 0.59 (95%CI 0.41-0.84), p=0.004, 2 RCT, n=546); improved grip strength (1.76 kg (95%CI 0.36-3.17), p<0.014, 4 RCT, n=219); increased intake of protein (p<0.001) and energy (p<0.001) with little reduction in normal food intake and improvements in weight (p<0.001). There was inadequate information to compare standard ONS (<20% energy from protein) with high protein ONS (>20% energy from protein). The systematic review and meta-analysis provides evidence that high protein supplements produce clinical benefits, with economic implications.