Malnutrition Diagnosis in Critically Ill Patients Using 2012 Academy of Nutrition and Dietetics/American Society for Parenteral and Enteral Nutrition Standardized Diagnostic Characteristics Is Associated With Longer Hospital and Intensive Care Unit Length of Stay and Increased In-Hospital Mortality

Background Standardized diagnostic criteria for malnutrition were developed by the Academy of Nutrition and Dietetics/American Society for Parenteral and Enteral Nutrition (AND/ASPEN) in 2012. The criteria as a whole has had little validation, and the effect of underlying condition on the impact of malnutrition has not been well studied. We measured the association between severe malnutrition and hospital length of stay (LOS), intensive care unit (ICU) LOS, and mortality among critically ill inpatients. Methods We analyzed hospital records from 5606 patients whose admission included an ICU stay. Associations between severe malnutrition and LOS and mortality were examined by multivariable linear and logistic regression. Results Thirteen percent were diagnosed with severe malnutrition. These had significantly longer hospital LOS (18 [interquartile range 10-35] days vs 8 [5-14] days), total ICU LOS (7 [3-15] days vs 3 [1-6] days) and in-hospital mortality (odds ratio [OR] 2.78, 95% confidence interval [CI] 2.33-3.31), compared with those without severe malnutrition. After adjusting for demographics, we found significant interactions between severe malnutrition and ICU location. Patients with malnutrition in the cardiothoracic surgery ICU experienced the largest increases in hospital LOS (21.10 days, 95% CI 18.58-23.61), ICU LOS (12.14 days, 95% CI 10.41-13.87), and in-hospital mortality (OR 8.78, 95% CI 5.11-15.07). Conclusion Critically ill patients diagnosed with severe malnutrition based on the AND/ASPEN diagnostic characteristics experienced longer hospital and ICU LOS and increased mortality. The magnitude of effect of malnutrition was modified by ICU location, underscoring the need to identify the major comorbidities associated with malnutrition.