RESUMO
BACKGROUND: The provision of nutrition support for critically ill patients in the early phase of intensive care unit (ICU) admission plays a vital role in their recovery. However, there is still debate regarding the impact of nutrition adequacy of critical illness phases. We aimed to investigate whether nutrition adequacy in the acute phase (early and late periods) is associated with 30-day mortality in critically ill patients. METHODS: We prospectively collected nutrition and clinical data from critically ill patients receiving exclusive enteral nutrition (EN) within the first 10 days of ICU admission. EN was classified as adequate when ≥80% of the prescribed EN was administered. Directed acyclic graphs were constructed to identify the minimum set of adjustment variables required to control for confounding factors. The relationships between energy and protein intake and 30-day mortality were assessed using the Cox regression analysis. RESULTS: A total of 119 patients were evaluated (70 years old, 56.3% male, and 68.1% with medical admission). The 30-day mortality rate was 23%. After adjusting for confounders, in the late period (days 5-10), energy adequacy (hazard ratio [HR] = 0.960; 95% CI, 0.937-0.984) and protein adequacy (HR = 0.960; 95% CI, 0.937-0.982) were predictors of 30-day mortality. No associations were observed in the early period (days 1-4) of the acute phase. CONCLUSION: In critically ill patients, nutrition adequacy (≥80% EN) during days 5-10 in the ICU was associated with a lower risk of 30-day mortality.