Antiphospholipid Syndrome (APS)
What is Antiphospholipid Syndrome (APS)?
Antiphospholipid syndrome is an autoimmune disease where your immune system mistakenly attacks normal proteins in your blood. These proteins help control blood clotting. When antibodies target them, your blood can clot too easily.
People with APS face higher risk of blood clots forming in veins and arteries throughout the body. These clots can travel to the lungs, brain, or other organs. Women with APS may also experience pregnancy complications including miscarriage and preterm birth.
APS can occur on its own or alongside other autoimmune conditions like lupus. Some people develop the antibodies but never have symptoms. Others experience serious clotting events that require immediate medical attention.
Symptoms
- Blood clots in legs, often causing pain, swelling, and redness
- Shortness of breath or chest pain from clots in the lungs
- Frequent miscarriages or pregnancy loss
- Stroke or mini-stroke symptoms in younger people
- Rash with a lacy, net-like pattern on the skin
- Severe headaches or migraines
- Memory problems or difficulty concentrating
- Low platelet count causing easy bruising or bleeding
Many people with antiphospholipid antibodies have no symptoms for years. The antibodies may only be discovered during testing for other conditions or after a clotting event occurs.
Concerned about Antiphospholipid Syndrome (APS)? Check your levels.
Screen for 1,200+ health conditions
Causes and risk factors
APS happens when your immune system produces antibodies against phospholipids, which are fats found in cell membranes and blood clotting proteins. Researchers do not fully understand why some people develop these antibodies. Genetics may play a role, as APS sometimes runs in families. Infections, medications, and other autoimmune diseases can trigger antibody production in susceptible individuals.
Risk factors include being female, having lupus or another autoimmune disease, and certain genetic markers. Age also matters, as APS typically appears between ages 20 and 50. Some infections like syphilis or Lyme disease can cause temporary antibody elevations. Certain medications may also trigger antibody formation, though this usually resolves after stopping the drug.
How it's diagnosed
Doctors diagnose APS using specialized blood tests that detect antiphospholipid antibodies. The main tests look for anticardiolipin antibodies, anti-beta-2 glycoprotein I antibodies, and lupus anticoagulant. These tests must show positive results on two separate occasions at least 12 weeks apart to confirm diagnosis.
Your doctor will also review your medical history for blood clots or pregnancy complications. A single positive antibody test is not enough for diagnosis. You need either a history of clotting events or pregnancy problems plus persistent antibody levels. Talk to your doctor about specialized testing if you have symptoms or risk factors for APS.
Treatment options
- Blood thinners like warfarin or heparin to prevent clots from forming
- Low-dose aspirin to reduce clotting risk in some patients
- Hydroxychloroquine for patients who also have lupus
- Specialized pregnancy management with heparin and aspirin for women trying to conceive
- Avoiding smoking, which increases clotting risk significantly
- Staying active and moving regularly to promote healthy circulation
- Maintaining a healthy weight to reduce stress on blood vessels
- Managing other autoimmune conditions that may worsen APS
- Regular monitoring of antibody levels and clotting factors
Frequently asked questions
APS is a separate autoimmune condition that causes blood clotting problems, while lupus can affect many body systems. About half of people with APS also have lupus. However, you can have APS without lupus, called primary APS. The two conditions require different treatment approaches, though some medications help both.
APS is usually a lifelong condition that requires ongoing management. Some people have temporary antibody elevations from infections or medications that disappear over time. However, if you meet the full diagnostic criteria for APS, the antibodies typically persist. Most people need long-term treatment to prevent complications.
Initial diagnosis requires positive antibody tests at least 12 weeks apart. After diagnosis, your doctor will monitor you regularly based on your treatment and symptoms. People on blood thinners often need monthly testing to ensure proper medication levels. Those with stable, well-managed APS may need testing every 3 to 6 months.
Yes, many women with APS have successful pregnancies with proper medical care. Treatment usually includes low-dose aspirin and heparin injections throughout pregnancy. Close monitoring by a high-risk pregnancy specialist is essential. With treatment, most women with APS can carry a pregnancy to term successfully.
Many factors can trigger clotting in APS, including long periods of sitting, surgery, pregnancy, or stopping blood thinners. Infections, injuries, and certain medications can also increase risk. Sometimes clots occur without any obvious trigger. This is why ongoing preventive treatment is so important for people with APS.
Not exactly, though both involve increased clotting risk. APS causes blood to clot too easily because of antibodies attacking clotting proteins. Thick blood usually refers to conditions where blood cells or proteins are too concentrated. APS is an autoimmune process, while thick blood has different causes like dehydration or genetic conditions.
While no specific diet treats APS, healthy eating supports overall vascular health. People on warfarin need to maintain consistent vitamin K intake from leafy greens. An anti-inflammatory diet may help reduce autoimmune activity. Staying hydrated and avoiding excess alcohol also supports healthy blood flow and reduces clotting risk.
Stopping blood thinners without medical supervision is dangerous and can lead to life-threatening clots. Your clotting risk returns quickly once medication is stopped. Never discontinue treatment on your own, even if you feel fine. Talk to your doctor if you have concerns about your medication or want to explore other options.
Stress can trigger inflammation and potentially worsen autoimmune conditions like APS. High stress may also lead to behaviors that increase clotting risk, like sitting for long periods or smoking. Managing stress through exercise, sleep, and relaxation techniques supports overall health. However, stress alone does not cause APS or replace the need for medical treatment.
Yes, wearing a medical alert bracelet is highly recommended for people with APS, especially those on blood thinners. Emergency responders need to know about your condition and medications if you cannot communicate. This information helps them provide appropriate care and avoid treatments that could cause dangerous bleeding. Include both your APS diagnosis and blood thinner medication on the bracelet.