Clinical Factors and Composite Biomarkers Associated with Intensive Care Unit-Acquired Weakness: A Retrospective Cohort Study

Background/Objectives: Intensive care unit-acquired weakness is a common neuromuscular complication among critically ill patients, but associations of readily available composite biomarkers with this condition remain insufficiently characterized. This study aimed to investigate the clinical characteristics, risk factors, and composite biomarkers associated with intensive care unit-acquired weakness. Methods: This single-center retrospective cohort study included 135 critically ill patients admitted to intensive care units between December 2020 and December 2023. Patients were classified into an intensive care unit-acquired weakness group (n = 57) and a group without intensive care unit-acquired weakness (n = 78) according to Medical Research Council sum score criteria. Clinical characteristics, laboratory parameters, composite biomarkers, and hospitalization outcomes were compared. Multivariable logistic regression and receiver operating characteristic curve analyses were performed. Results: Older age, sepsis, hemodialysis, mechanical ventilation, and glucocorticoid use remained associated with intensive care unit-acquired weakness after adjustment for the other covariates in the model. Affected patients had lower albumin and hemoglobin levels and longer intensive care unit and hospital stays. The neutrophil-to-albumin ratio, inflammatory burden index, creatinine-to-albumin ratio, and serum urea-to-creatinine ratio were higher in affected patients. Receiver operating characteristic analysis showed modest discrimination, with areas under the curve ranging from 0.602 to 0.665. Conclusions: Intensive care unit-acquired weakness was associated with clinical and treatment-related factors, hypoalbuminemia, prolonged hospitalization, and elevated composite biomarkers. The composite biomarkers showed only modest discrimination, and their incremental values beyond clinical assessment and clinical utility remain unestablished. Residual confounding by illness severity and nutritional exposure cannot be excluded.