Angiotensin II as a Novel Biomarker in the Assessment and Prediction of Post-burn Hypertrophic Scarring: A Propensity Score-Matched Cohort Study.

BACKGROUND

Hypertrophic scar (HS) is a common complication following burn injuries. The current evaluation of HS predominantly depends on subjective perception. This study aimed to investigate an objective biomarker for evaluating the proliferative activity and predicting susceptibility to post-burn HS.

METHODS

This retrospective cohort study enrolled 104 burn patients and 16 patients with post-burn HS. Serial serum Angiotensin II (AngII) levels were measured from admission to wound healing (371 measurements total). The primary outcome was the correlation between AngII levels and Vancouver Scar Scale (VSS) scores in patients not receiving anti-scar treatment. Propensity score matching was employed to balance confounding factors. In vitro experiments assessed AngII effects on fibroblast proliferation.

RESULTS

The study found that serum AngII levels follow a dynamic trend from burn injury to wound healing, increasing 2-3 fold during proliferation and remodeling phases and remaining elevated post-healing, aligning with fibroblast activity. In vitro, AngII stimulated fibroblast proliferation. AngII levels correlated with age (P<0.05), being significantly higher in younger patients (200.61 vs 58.32 pg/ml), but not with burn index or sex. In patients with post-burn hypertrophic scars, AngII positively correlated with Vancouver Scar Scale scores (R2=0.797). A linear model using AngII to predict VSS scores was developed and validated.

CONCLUSION

This first systematic characterization of post-burn serum AngII dynamics reveals that sustained AngII elevation may serve as a biomarker for active HS proliferation. AngII demonstrates potential for predicting individual HS susceptibility and identifying optimal timing for anti-scar therapy, providing a novel molecular basis for future personalized post-burn HS management research.

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