The association between pre-operative malnutrition and post-amputation clinical outcomes: A systematic review

Background: In patients who underwent lower limb amputation (LLA), the prevalence of malnutrition and its association with clinical outcomes are unclear. Objectives: This systematic review aims to identify literature and summarise existing information on (1) the prevalence of malnutrition in the patients with LLA and (2) the association between pre-operative nutritional status and post-surgery clinical outcomes in patients who require amputation. Methods: A search was conducted in four electronic databases (Cochrane Central Register of Controlled Trials (CENTRAL), PubMed, CINAHL and Scopus) to identify eligible studies. The search strategy was based on keywords – amputation, malnutrition and undernutrition. Article were included regardless of the study design; and if they were written in English; included adult patients with lower limb or foot amputation; and performed pre-amputation nutrition assessments. Results: Seven articles met the eligibility criteria. Malnutrition was assessed by biochemistry and/or anthropometry – none of which are validated nutrition assessment tools. Nevertheless, abnormal biochemistry and/or anthropometry results were associated with delayed wound healing, complications and failed amputation compared to normal ranges. The association between abnormal biochemistry and/or anthropometry parameters and mortality was less consistent. Only one study used a validated nutrition screen tool and found half of the population with LLA were at risk of malnutrition, but no association was reported. Conclusions: The association between malnutrition and clinical outcomes in patients who underwent LLA remains unclear as all the eligible studies that investigated association used unvalidated nutrition assessment tools. There is an urgent need to address this knowledge gap in future research.