Illness-related malnutrition has been reported in 10% to 55% of ill people in both hospital and in the community in areas of food sufficiency. It has been suggested that dietary counselling to encourage the use of energy- and protein-rich foods should be used in preference to oral nutritional supplements in the management of illness-related malnutrition.
To examine the evidence that dietary advice to improve nutritional intake in adults with illness-related malnutrition can improve survival, weight and anthropometry and to estimate the size of any additional effect of whole protein nutritional supplements when given in combination with dietary advice.
Relevant publications were identified from comprehensive electronic database searches and handsearching of relevant journals and abstract books of conference proceedings. Additional studies were sought by contacting dietitians, clinicians and manufacturers of nutritional supplements.
Date of most recent search: April 2003.
All randomised controlled trials (RCT) of dietary advice compared with: no advice; oral nutritional supplements; and dietary advice plus oral nutritional supplements, in people with illness-related malnutrition.
Data collection and analysis
Two reviewers independently assessed study eligibility, methodological quality and extracted data.
Twenty-four studies (25 comparisons), with 2135 participants were included. A group of seven studies were identified comparing dietary advice plus supplements if required with no advice and included as a separate post hoc comparison. Duration of follow up ranged from 16 days to 24 months. There was no significant difference in mortality for each comparison, or in weight change for either dietary advice compared with no advice (one study) weighted mean difference (WMD) -0.03 kg (95% confidence interval (CI) -0.69 to 0.63); advice compared with advice plus supplements (four studies), WMD -0.09 kg (95%CI -0.63 to 0.46); or for advice plus supplements if required compared with no advice (one study) WMD 1.10 (95% CI -0.96 to 3.16). Compared with groups receiving only dietary advice, groups receiving supplements gained significantly more (or lost significantly less) weight (four studies), WMD 1.09 kg (95%CI 0.29 to 1.90). Few data were available for other outcomes.
This review highlights the lack of evidence for the provision of dietary advice in the management of illness-related malnutrition. Results suggest oral nutritional supplements may be more effective than dietary advice, or provide an additional benefit in enhancing short-term weight gain, but whether this can be sustained, or whether survival and morbidity are also improved remains uncertain. A large adequately-powered RCT is needed to compare the efficacy of different forms of therapy to increase dietary intake in people with illness-related malnutrition and to examine the impact of this on clinical function and survival.