The Relationship of Nutrition and Pressure Ulcers

Multiple definitions for malnutrition syndromes are found in the literature resulting in confusion. Recent evidence suggests that varying degrees of acute or chronic inflammation are key contributing factors in the pathophysiology of malnutrition that is associated with disease or injury. An International Guideline Committee was constituted to develop a consensus approach to defining malnutrition syndromes for adults in the clinical setting. Consensus was achieved through a series of meetings held at the A.S.P.E.N. and ESPEN Congresses. It was agreed that an etiology-based approach that incorporates a current understanding of inflammatory response would be most appropriate. The Committee proposes the following nomenclature for nutrition diagnosis in adults in the clinical practice setting. "Starvation-related malnutrition", when there is chronic starvation without inflammation, "chronic disease-related malnutrition", when inflammation is chronic and of mild to moderate degree, and "acute disease or injury-related malnutrition", when inflammation is acute and of severe degree. This commentary is intended to present a simple etiology-based construct for the diagnosis of adult malnutrition in the clinical setting. Development of associated laboratory, functional, food intake, and body weight criteria and their application to routine clinical practice will require validation.

There have been few systematic reviews and no meta-analyses of the clinical benefits of nutritional support in patients with, or at risk of developing, pressure ulcers. Therefore, this systematic review and meta-analysis was undertaken to address the impact of enteral nutritional support on pressure ulcer incidence and healing and a range of other clinically relevant outcome measures in this group. Fifteen studies (including eight randomised controlled trials (RCTs)) of oral nutritional supplements (ONS) or enteral tube feeding (ETF), identified using electronic databases (including Pub Med and Cochrane) and bibliography searches, were included in the systematic review. Outcomes including pressure ulcer incidence, pressure ulcer healing, quality of life, complications, mortality, anthropometry and dietary intake were recorded, with the aim of comparing nutritional support versus routine care (e.g. usual diet and pressure ulcer care) and nutritional formulas of different composition. Of these 15 studies, 5 RCTs comparing ONS (4 RCTs) and ETF (1 RCT) with routine care could be included in a meta-analysis of pressure ulcer incidence. Meta-analysis showed that ONS (250-500 kcal, 2-26 weeks) were associated with a significantly lower incidence of pressure ulcer development in at-risk patients compared to routine care (odds ratio 0.75, 95% CI 0.62-0.89, 4 RCTs, n=1224, elderly, post-surgical, chronically hospitalised patients). Similar results were obtained when a combined meta-analysis of ONS (4 RCT) and ETF (1 RCT) trials was performed (OR 0.74, 95% CI 0.62-0.88, 5 RCTs, n=1325). Individual studies showed a trend towards improved healing of existing pressure ulcers with disease-specific (including high protein) versus standard formulas, although robust RCTs are required to confirm this. Although some studies indicate that total nutritional intake is improved, data on other outcome measures (quality of life) are lacking. This systematic review shows enteral nutritional support, particularly high protein ONS, can significantly reduce the risk of developing pressure ulcers (by 25%). Although studies suggest ONS and ETF may improve healing of PU, further research to confirm this trend is required.