Serum complement C3/C4 ratio, a novel marker for recurrent cardiovascular events

Area of Science:

• Cardiology
• Immunology
• Biochemistry

Background:

• Acute coronary syndrome (ACS) is characterized by inflammation and complement cascade activation.
• The role of complement system components in predicting cardiovascular events in ACS patients requires further investigation.

Purpose of the Study:

• To evaluate the serum complement C3 and C4 concentration ratio (C3/C4 ratio) as a predictive marker for subsequent ischemic cardiovascular events in patients with ACS.
• To determine if the C3/C4 ratio is an independent risk factor for recurrent cardiovascular events after an initial ACS episode.

Main Methods:

• A cohort of 148 ACS patients was followed for a median of 555 days for major adverse cardiovascular events.
• Serum samples were collected at multiple time points: hospitalization, 1 week, 3 months, and 1 year post-admission.
• Serum C3 and C4 concentrations were measured, and the C3/C4 ratio was calculated and analyzed using statistical models, including Cox regression.

Main Results:

• Patients who experienced subsequent cardiovascular events had a significantly higher C3/C4 ratio throughout the follow-up period compared to those who did not (p=0.007).
• The C3/C4 ratio was identified as a novel independent risk factor for new cardiovascular events (OR 1.33, p=0.007).
• Patients in the highest quartile of the C3/C4 ratio had a 3.04-fold increased risk of experiencing an event compared to those in the lowest quartiles (p=0.01).

Conclusions:

• An elevated serum C3/C4 ratio is a novel and readily available marker for predicting recurrent cardiovascular events in patients with acute coronary syndrome.
• The findings suggest that changes in complement C3 and C4 protein levels contribute to cardiovascular risk stratification in ACS.
• The C3/C4 ratio offers a potential tool for enhanced risk assessment and management strategies in ACS patients.