Core outcome sets and trials of nutrition and metabolism interventions

The target of critical care nutrition research is moving from short-term physiological surrogate endpoints and mortality toward long-term patient-centered outcomes. This review summarizes recent core outcome set (COS) initiatives relevant to nutrition and metabolism and outcome selection in recent trials.

The Core Outcome Measures for Clinical Effectiveness Trials of Nutritional and Metabolic Interventions in Critical Illness (CONCISE) defined essential outcomes: survival, physical function, infection, activities of daily living, nutritional status, and muscle/nerve function to be assessed at 30 and 90 days after randomization, with suggested but nonmandated instruments to preserve feasibility. COSMOGI (core outcome set of daily monitoring of gastrointestinal function in critically ill patients) standardizes daily gastrointestinal monitoring during critical illness. Large, randomized trials testing higher protein or early aggressive energy delivery have not improved survival and functional recovery, although the latter has only recently received more attention. From a mechanistic perspective, outcome selection in critical care nutrition and gastrointestinal function research should prioritize patient-centered (i.e. functional and patient-reported) outcomes.

Standardizing outcome selection should improve interpretability and evidence synthesis. Future trials should incorporate robust functional and patient-reported outcomes. Core outcome sets will need updates when new assessment tools (i.e., biomarkers, new functional tests, standardized ultrasound protocols) emerge.