Association Between Calorie Intake And Clinical Outcome In Critically Ill Patients

Background: There is controversy over the optimal energy delivery in intensive care units(ICUs).According to the recommendation of recent ESPEN guidelines regarding the optimal energy delivery,we did a post-hoc analysis of NEED trial and aimed to evaluate the association between different caloric adequacy assessed by a weight-based equation and short-term clinical outcomes in a cohort of critically ill patients.Methods: This is a post-hoc analysis of a cluster-randomized controlled trial(N=2772).Energy requirement was estimated as 25 kcal/kg of body weight.The study subjects were divided into three groups according to their caloric adequacy as calculated by the mean energy delivered during day 3to day 7 of enrollment divided by the estimated energy requirements: 1)received <70% of energy requirement(hypocaloric),2)received 70%-100% of energy requirement(normocaloric),3)received >100% of energy requirement(hypercaloric).Cox proportional hazards models were used to analyze association between caloric adequacy and 28-day mortality and time to discharge alive from the ICU.Results: A total of 1694 patients were included.Compared with normocaloric feeding,hypocaloric feeding significantly increased the risk of 28-day mortality(hazard ratio [HR] = 1.590,95%confidence interval [CI]: 1.162-2.176,P = 0.004),while hypercaloric feeding did not.After controlling for potential confounders,the association remained valid(adjusted HR = 1.606,95% CI:1.160-2.222,P = 0.004).The caloric adequacy was not associated with time to discharge alive from the ICU in the unadjusted and the adjusted models.Conclusion: Energy delivery below 70% of estimated energy requirement during the first week of critical illness is associated with 28-day mortality.