A review of reviews: A new look at the evidence for oral nutritional supplements in clinical practice

Abstract

Summary Decisions about the treatment of disease-related malnutrition should be guided where possible by evidence. Increasing numbers of systematic reviews and meta-analyses have reviewed the efficacy of oral nutritional supplements for treating disease-related malnutrition. In order to consolidate this evidence, an overview of systematic reviews and meta-analyses (‘review of reviews’) in which oral nutritional supplements were compared with routine care was undertaken, focussing primarily on clinical outcomes. Thirteen systematic reviews and meta-analyses were reviewed (up to August 2006), either of trials in adults, including the elderly, with a variety of conditions (6 reviews), or in specific groups, including chronic renal disease, diabetes, cancer, chronic obstructive pulmonary disease (COPD), hip fracture and gastrointestinal surgery (7 reviews). This review of reviews found largely consistent clinical benefits with oral nutritional supplements in meta-analyses of trials across patient groups. Benefits included significant reductions in mortality and complications (e.g. infections, pressure ulcers), particularly in acute settings and acutely ill geriatrics. In some specific groups there were reductions in complications (in gastrointestinal surgery, hip fracture) but in other groups (e.g. COPD, chronic renal disease) more research is needed to assess relevant clinical outcomes. Across reviews of all patient groups, oral nutritional supplements consistently improved total nutritional intake, with little suppression of food intake. In general, reviews indicated improvements in weight (weight gain or less weight loss) with oral nutritional supplements. The only systematic review comparing oral nutritional supplements with dietary advice showed greater intakes and weight gain with oral nutritional supplements. In summary, there is increasing evidence to support the use of oral nutritional supplements in clinical practice, particularly in acutely ill and older patients. Future research must be well designed in order to ascertain the most effective ways of using oral nutritional supplements and other dietary strategies to optimally treat disease-related malnutrition.