Malnutrition, Critical Illness Survivors, and Postdischarge Outcomes: A Cohort Study

Abstract

Background: We hypothesized that preexisting malnutrition in patients who survived critical care would be associated with adverse outcomes following hospital discharge.

Methods: We performed an observational cohort study in 1 academic medical center in Boston. We studied 23,575 patients, aged ≥18 years, who received critical care between 2004 and 2011 and survived hospitalization.

Results: The exposure of interest was malnutrition determined at intensive care unit (ICU) admission by a registered dietitian using clinical judgment and on data related to unintentional weight loss, inadequate nutrient intake, and wasting of muscle mass and/or subcutaneous fat. The primary outcome was 90-day postdischarge mortality. Secondary outcome was unplanned 30-day hospital readmission. Adjusted odds ratios were estimated by logistic regression models adjusted for age, race, sex, Deyo-Charlson Index, surgical ICU, sepsis, and acute organ failure. In the cohort, the absolute risk of 90-day postdischarge mortality was 5.9%, 11.7%, 15.8%, and 21.9% in patients without malnutrition, those at risk of malnutrition, nonspecific malnutrition, and protein-energy malnutrition, respectively. The odds of 90-day postdischarge mortality in patients at risk of malnutrition, nonspecific malnutrition, and protein-energy malnutrition fully adjusted were 1.77 (95% confidence interval [CI], 1.23-2.54), 2.51 (95% CI, 1.36-4.62), and 3.72 (95% CI, 2.16-6.39), respectively, relative to patients without malnutrition. Furthermore, the presence of malnutrition is a significant predictor of the odds of unplanned 30-day hospital readmission.

Conclusions: In patients treated with critical care who survive hospitalization, preexisting malnutrition is a robust predictor of subsequent mortality and unplanned hospital readmission.

Keywords: ICU survivors; critical care; hospital readmission; malnutrition; mortality; outcomes.

Figure 1. Survival Analysis by Nutrition Status

Note: Unadjusted event rates were calculated with the use of the Kaplan-Meier methods and compared with the use of the log-rank test. Categorization of nutrition status is per the primary analyses. The global comparison log rank p value is <0.001.