Plasma complement component C2: a potential biomarker for predicting abdominal aortic aneurysm related complications

Area of Science:

• Cardiovascular Research
• Biomarker Discovery
• Aortic Disease Management

Background:

• Abdominal aortic aneurysm (AAA) complications pose a significant health burden.
• Reliable blood-based predictors for AAA progression are needed to improve patient outcomes.
• The prognostic role of complement factors in AAA remains underexplored.

Purpose of the Study:

• To evaluate the prognostic performance of complement factors in predicting AAA-related clinical outcomes.
• To assess plasma C2 levels as a potential biomarker for AAA progression and adverse events.
• To investigate the association between complement factor levels and AAA expansion, major adverse aortic events (MAAE), and major adverse cardiovascular events (MACE).

Main Methods:

• Pilot study involving 75 AAA patients and 75 non-AAA controls.
• Baseline and 2-year prospective measurement of plasma complement protein levels.
• Primary outcome: rapidly progressing AAA (aortic expansion).
• Secondary outcomes: MAAE and MACE.
• Multivariable Cox regression analyses to determine prognostic value of plasma C2.

Main Results:

• AAA patients showed significantly different plasma concentrations of complement factors compared to non-AAA controls (e.g., lower C2, C3, C4b).
• Plasma C2 was the strongest predictor of rapid aortic expansion (HR 0.10, p=0.040), MAAE (HR 0.09, p=0.001), and MACE (HR 0.14, p=0.011) after 24 months.
• Higher C2 levels at admission predicted greater risk for rapid aortic expansion and MAAE in AAA patients.

Conclusions:

• Plasma C2 demonstrates potential as a biomarker for predicting rapid aortic expansion in AAA patients.
• C2 levels may help identify patients at higher risk for MAAE, guiding intervention decisions.
• Further research is warranted to validate C2 as a clinical tool for AAA management.