ICU-acquired weakness in critically ill patients at risk of malnutrition: risk factors, biomarkers, and early enteral nutrition impact.

Background: This study aimed to explore the risk factors associated with intensive care unit-acquired weakness (ICU-AW) in critically ill patients at risk of malnutrition and to evaluate the efficacy of early enteral nutrition (EEN) and the role of biomarkers in managing ICU-AW.

Methods: This retrospective, observational cohort study included 180 patients at risk of malnutrition admitted to the emergency intensive care unit of the First Affiliated Hospital of Xiamen University Hospital from January 2022 to December 2023. Patients were divided into ICU-AW group and non-ICU-AW group according to whether they developed ICU-AW, or categorized into EEN and parenteral nutrition (PN) groups according to nutritional support. ICU-AW was diagnosed using the Medical Research Council score. The primary outcome was the occurrence of ICU-AW.

Results: The significant factors associated with ICU-AW included age, sex, type of nutritional therapy, mechanical ventilation (MV), body mass index (BMI), blood urea nitrogen (BUN), and creatinine (Cr) levels (P<0.05). The PN group developed ICU-AW earlier than did the EEN group, with a significant difference observed (log-rank P<0.001). Among biomarkers for ICU-AW, the mean prealbumin (PAB)/C-reactive protein (CRP) ratio had the highest diagnostic accuracy (area under the curve [AUC] 0.928, 95% confidence interval [95% CI] 0.892-0.946), surpassing the mean Cr/BUN ratio (AUC 0.740, 95% CI 0.663-0.819) and mean transferrin levels (AUC 0.653, 95% CI 0.574-0.733).

Conclusion: Independent risk factors for ICU-AW include female sex, advanced age, PN, MV, lower BMI, and elevated BUN and Cr levels. EEN may potentially delay ICU-AW onset, and the PAB/CRP ratio may be an effective diagnostic marker for this condition.