More Food for Thought: Nutrition, the Nutrition Risk in the Critically Ill Score, and the Dilemma of “Goal” Feeding*
In this issue of Critical Care Medicine, Compher et al (2) report an intriguing analysis of data from the prospective observational International Nutrition Survey 2013. This web-based survey collected detailed nutrition-related information, standard demographic and disease-related variables, and patient outcomes from 4,040 subjects in 202 ICUs. The primary objective of this analysis was to evaluate the utility of the Nutrition Risk in the Critically Ill (NUTRIC) score and whether more aggressive delivery of nutritional therapy was associated with improved outcomes (primarily 60-d mortality) among patients classified as “high risk” by the NUTRIC score. The authors used a modified NUTRIC score (omitting the serum interleukin-6 level used in the original description) and defined the high-risk cohort as those patients with a score of greater than or equal to 5 (range, 0–9). Standard logistic regression models were then created to examine the interaction between the NUTRIC risk category and caloric (or protein) intake on 60-day mortality. For the entire cohort as a whole, they found that there was no significant interaction between the NUTRIC category, amount of protein or total caloric intake, and mortality. However, in the adjusted analyses, they found a relatively consistent relationship between protein or calorie intake and mortality among patients categorized as high risk by the NUTRIC score, whereas there was no significant similar relationship found in the low-risk cohort. For every 10% increase in either protein intake or total caloric intake, there was a corresponding decrease in the mortality ranging from 6.6% to 11.6%. The authors suggest that the NUTRIC score may be a useful metric to identify those ICU patients who are at the highest risk of poor outcomes, and who may benefit from early and more aggressive delivery of full nutritional support. In the conclusions, they support the practice of attempting to feed all ICU patients at goal protein and calorie levels, understanding that those patients with less severe disease or lower NUTRIC scores may receive no additional benefit.
This is an important and very well-done study that attempts to validate the NUTRIC score as not only a valid prognostic measure but also as a clinically useful scoring system that could be used to guide the timing of initiating nutritional support and the aggressiveness of delivering higher levels of protein and energy (calories) (3).