Association between weight change and clinical outcomes in critically ill patients

Purpose: Body weight fluctuates daily throughout a patient's stay in the intensive care unit (ICU) due to a variety of factors, including fluid balance, nutritional status, type of acute illness, and presence of comorbidities. This study investigated the association between change in body weight and clinical outcomes in critically ill patients during short-term hospitalization in the ICU.

Methods: All patients admitted to the Gyeongsang National University hospital between January 2010 and December 2011 who met the inclusion criteria of age 18 or above and ICU hospitalization for at least 2 days were prospectively enrolled in this study. Body weight was measured at admission and daily thereafter using a bed scale. Univariate and multivariate linear and logistic regression analyses were performed to evaluate factors associated with mortality and the association between changes in body weight and clinical outcomes, including duration of mechanical ventilation (MV) use, length of ICU stay, and ICU mortality.

Results: Of the 140 patients examined, 33 died during ICU hospitalization, yielding an ICU mortality rate of 23.6%. Non-survivors experienced higher rates of severe sepsis and septic shock and greater weight gain than survivors on days 2, 3, 4, 5, and 6 of ICU hospitalization (P < .05). Increase of body weight on days 2 through 7 on ICU admission was correlated with the longer stay of ICU, and increase on days 3 through 7 on ICU admission was correlated with the prolonged use of mechanical ventilation. Increase of body weight on days 3 through 5 on ICU admission was associated with ICU mortality.

Conclusions: Increase in body weight of critically ill patients may be correlated with duration of mechanical ventilation use and longer stay of ICU hospitalization and be associated with ICU mortality.