Evaluation of the ASPEN guidelines for refeeding syndrome among hospitalized patients receiving enteral nutrition: A retrospective cohort study

Background Until recently, refeeding syndrome (RFS) has lacked standardized diagnostic criteria. This study sought to (1) determine whether RFS, as operationalized in the 2020 American Society for Parenteral and Enteral Nutrition (ASPEN) guideline definition, is associated with adverse clinical outcomes and (2) identify key risk factors for RFS. Methods In this retrospective cohort study, adults hospitalized from 2015 to 2019 were included if they were ordered for enteral feeding during hospitalization. Data were collected for up to 30 days, and RFS was operationalized as per the ASPEN 2020 guidelines as a >= 10% (corresponding to mild RFS), >= 25% (moderate), and >= 50% (severe) decline in prefeeding serum phosphorus, magnesium, or potassium. The mortality associated with RFS was assessed, and risk factors for RFS were identified using multivariable logistic regression modeling. Results Of 3854 participants, 3480 (90%) developed mild RFS. Thirty-day mortality was higher in those without mild RFS (24%) than in those with mild RFS (18%) (P < 0.01). When RFS was reoperationalized as a 50% decline in electrolytes, 25% of patients developed RFS with a 20% 30-day mortality. Risk factors for development of RFS included renal failure, elevated creatinine, and low platelets; additionally, prefeeding serum phosphorus level was strongly associated with development of RFS (adjusted odds ratio, 6.09; 95% confidence interval, 4.95-7.49 for those in the highest tertile of prefeeding phosphorus compared with the lowest). Conclusion The ASPEN operationalization of RFS as a decline in baseline electrolyte values was not associated with death. Prefeeding serum phosphorus level strongly predicted severe RFS.