C-reactive Protein-to-albumin Ratio (CAR) in Polytrauma—Early Warning or Marker of Disease Evolution?
Year: 2026
Type: article
Abstract: We read with great interest the article by Salem et al. presenting a prospective observational study on the role of the C-reactive protein-to-albumin ratio (CAR) as a predictor of postoperative systemic inflammatory response syndrome (SIRS) and sepsis in polytrauma patients after intensive care unit (ICU) admission.1 The authors discuss a relevant and pragmatic challenge addressed by trauma critical care: Recognizing those patients who are at greater risk for developing both inflammation and infection, by using inexpensive, widely used biomarkers that can easily be monitored numerous times.However, the authors feel that there are still certain important considerations for CAR to be accepted as a tool to make "early predictions" for postoperative care of polytrauma patients; timing should coincide with the clinical timeline.The highest discriminatory power for the study was evident on day 5 after surgery, where the area under the curve (AUC) was extremely high.While this is encouraging, day 5 may represent a stage when many patients already demonstrate evolving clinical and laboratory features of systemic inflammation or infection; at that point, CAR may function more as a marker of ongoing disease evolution or severity rather than an early warning signal.A practical refinement would be to foreground the admission, day 1, and day 3 performance and frame day 5 CAR as confirmatory stratification, rather than early prediction.While the authors describe CAR as a tool for early antibiotic therapy, this information is not specific to postoperative infections.Thus, CAR alone should not guide antibiotic initiation without clinical signs of infection.The absence of multivariable adjustment limits inference about independent predictive value.Trauma and postoperative inflammatory responses are strongly influenced by injury severity, shock burden, transfusion exposure, fluid resuscitation, operative contamination, and baseline comorbidities.In this analysis, CAR appears largely evaluated through unadjusted group comparisons and receiver operating characteristic (ROC) analyses.This approach risks confounding since albumin and C-reactive protein (CRP) are both sensitive to physiologic perturbations common in ICU resuscitation.We suggest adding multivariable models (e.g., logistic regression for binary outcomes; or mixedeffects models for repeated measures), including clinically relevant covariates such as age, injury severity indices (injury severity score [ISS]/new injury severity score [NISS]), baseline sequential organ failure assessment score (SOFA)/acute physiology and chronic health evaluation (APACHE), vasopressor requirement, transfusion volume, fluid balance, and type/contamination class of surgery.If feasible, reporting incremental value over clinical models (ΔAUC, net reclassification) would better establish whether CAR adds information beyond established predictors.
Institution: Rajendra Institute of Medical Sciences
Language: English
Subfield: Epidemiology
Field: Medicine
Domain: Health Sciences
Open Access status: diamond
OpenAlex ID: W7130643606