Fibrinogen is a protein produced by the liver that circulates in the blood. It is a component of hemostasis, the body’s process for stopping bleeding. When a blood vessel is injured, an enzyme called thrombin converts fibrinogen into insoluble strands of fibrin. These fibrin strands form a mesh-like structure that is the backbone of a stable blood clot. This fibrin mesh traps platelets and red blood cells, sealing the injury and providing a scaffold for tissue repair.
Understanding Fibrinogen Levels
The amount of functional fibrinogen in the blood is measured through a fibrinogen activity test. This test assesses how long it takes for a clot to form after a standard amount of thrombin is added to a plasma sample. The results are reported in milligrams per deciliter (mg/dL), and a normal fibrinogen level for an adult is between 200 and 400 mg/dL.
Levels above this range are considered elevated. For instance, values between 400 and 600 mg/dL may be categorized as moderately high, while levels exceeding 700 mg/dL are considered very high and may signal an increased risk of clot formation. It is important to have these results interpreted by a healthcare provider, who will consider them in the context of your overall health and medical history.
Causes of Elevated Fibrinogen
Persistently high fibrinogen levels often signal an underlying health issue, with inflammation being a primary driver. Fibrinogen is an acute-phase reactant, meaning the liver increases its production in response to systemic inflammation, infection, or tissue injury. Consequently, any condition that causes acute or chronic inflammation can lead to elevated fibrinogen.
Chronic inflammatory diseases are a common cause of high fibrinogen. Conditions such as rheumatoid arthritis, inflammatory bowel disease, and certain kidney diseases are associated with persistently high levels. Cancers, particularly those of the stomach, breast, and kidneys, can also trigger this inflammatory response and raise fibrinogen.
Lifestyle and cardiovascular factors play a role. Smoking, obesity, and a sedentary lifestyle are all linked to chronic inflammation and higher fibrinogen levels. Conditions like atherosclerosis, coronary artery disease, and diabetes are also associated with elevated fibrinogen. Other causes include recent trauma, surgery, burns, and pregnancy, where levels rise to protect against bleeding during delivery.
Health Implications of High Fibrinogen
While fibrinogen is necessary for normal clotting, elevated levels are a risk factor for developing abnormal blood clots, a condition known as thrombosis. High concentrations of this protein increase blood viscosity, making it thicker, and promote the aggregation of platelets, which can lead to dangerous clots within blood vessels. These clots can obstruct blood flow and lead to serious cardiovascular events.
The presence of high fibrinogen is linked to an increased risk for several specific thrombotic conditions. It is a recognized risk factor for heart attacks and strokes, as clots can form in the arteries supplying the heart or brain. Elevated fibrinogen is also associated with an increased risk of developing a pulmonary embolism (PE) and deep vein thrombosis (DVT). Chronically high levels can contribute to the progression of atherosclerosis, further heightening the risk of cardiovascular disease over time.
Managing and Lowering High Fibrinogen
The primary strategy for managing high fibrinogen is to identify and address the underlying cause. Since elevated levels are often a response to inflammation or another medical condition, working with a healthcare provider to treat that root issue is the main approach. Medications used are typically aimed at the underlying condition or at reducing overall clot risk, rather than targeting fibrinogen directly.
Lifestyle modifications can also have a positive impact on lowering fibrinogen levels and reducing associated cardiovascular risk. Quitting smoking is one of the most effective changes one can make. Maintaining a healthy weight through a combination of diet and exercise is also beneficial, as obesity contributes to chronic inflammation.
Regular physical activity, particularly aerobic exercises like jogging or cycling, has been shown to help lower fibrinogen. Adopting a heart-healthy diet rich in fruits, vegetables, and whole grains can help reduce inflammation. Increasing the intake of omega-3 fatty acids and managing stress through techniques like mindfulness or yoga can also be helpful.