Fibrinogen is a soluble plasma protein produced by the liver that plays a central role in blood clotting. When vascular injury occurs, thrombin converts fibrinogen into fibrin, which forms the structural scaffold of a blood clot. Fibrinogen is also an acute phase reactant, rising significantly with inflammation, infection, and tissue injury.
Elevated fibrinogen is associated with increased cardiovascular risk, as it promotes platelet aggregation, increases blood viscosity, and is a key component of clot formation. High fibrinogen is an independent cardiovascular risk factor and is particularly relevant in people with metabolic syndrome, type 2 diabetes, or a strong family history of cardiovascular disease. Low fibrinogen, conversely, indicates impaired clotting capacity and increased bleeding risk.
FAQs
Is elevated fibrinogen a serious finding?
Persistently elevated fibrinogen is an independent cardiovascular risk factor, increasing the risk of heart attack and stroke. It reflects underlying inflammation and increased blood coagulability. It warrants investigation of contributing causes and lifestyle modification, particularly smoking cessation and exercise.
How does fibrinogen relate to ESR?
Fibrinogen is the primary protein responsible for elevated ESR. When fibrinogen is high, red blood cells aggregate more readily (rouleaux formation) and settle faster. Both fibrinogen and ESR rise with inflammation, and high fibrinogen is a major contributor to elevated ESR.
Can I lower fibrinogen with diet?
Yes. A Mediterranean-style diet, omega-3 fatty acids from oily fish, and reduction in processed foods and smoking are the most evidence-based dietary approaches for lowering fibrinogen. Regular aerobic exercise has the most consistent effect.
What does very low fibrinogen mean?
Very low fibrinogen indicates a clotting disorder with significant bleeding risk. The most common serious causes are DIC (widespread intravascular clotting consuming fibrinogen), severe liver disease, and congenital afibrinogenaemia. It requires urgent medical assessment.
