Effect of acute phase protein dose on clinical outcomes in critically ill patients

Protein intake guidelines for critically ill patients during the acute phase vary significantly. In Japan, where many patients are older, underweight, and thinner compared to other countries, it is unclear whether international recommendations are applicable. This study aimed to evaluate the impact of protein administration on the survival of critically ill patients on ICU days 4 and 7.

This retrospective study included adult patients admitted to the intensive care unit (ICU) of Sapporo Medical University Hospital between February 2018 and November 2023. Eligible patients received artificial nutrition (enteral and/or parenteral) and remained in the ICU for >8 days. Patients were categorized into three groups based on protein intake quartiles on ICU days 4 and 7: Low Protein (<0.8 g/kg/day), Middle Protein (0.8-1.4 g/kg/day), and High Protein (≥1.4 g/kg/day). The association between protein dose and survival was analyzed.

A total of 262 patients met the inclusion criteria. On ICU day 4, the HP group demonstrated significantly lower day 28 survival (adjusted HR: 1.941, 95 % CI: 1.018-3.701) and day 90 survival (adjusted HR: 1.683, 95 % CI: 1.007-2.815) compared to the MP group. High protein dose on day 4 was identified as an independent risk factor for poorer clinical outcomes. However, protein dose on ICU day 7 was not associated with survival outcomes.

In critically ill patients in Japan, high-dose protein administration (≥1.4 g/kg/day) on ICU day 4 may adversely affect clinical outcomes. Careful consideration of protein dosing during the early acute phase is recommended.