Antiphospholipid Syndrome (APS) Treatment in Singapore
MBChB (New Zealand), PGDipObstMedGyn, FRACP (New Zealand), FAMS (Rheumatology)
Antiphospholipid syndrome (APS) is an autoimmune condition in which the immune system produces antiphospholipid antibodies associated with an increased risk of blood clots. These clots can occur in veins or arteries, and may lead to complications such as deep vein thrombosis (DVT), pulmonary embolism, heart attack or stroke. APS can also affect pregnancy, increasing the risk of miscarriage, pre-eclampsia and other pregnancy complications.
Some people with APS experience blood clots or pregnancy complications, while others may be found to have antiphospholipid antibodies during investigations. However, having these antibodies does not necessarily mean a person has APS, as they can be present without causing clinical symptoms or complications.
With appropriate assessment, monitoring and treatment tailored to individual risk factors, the risk of blood clots and other complications can often be reduced. At the Centre for Rheumatology & Arthritis, Dr Poh takes an individualised approach to APS management, considering your medical history, antibody profile, risk factors and long-term health needs to guide care.
Causes and Risk Factors of Antiphospholipid Syndrome
Antiphospholipid syndrome is an autoimmune condition in which the immune system produces antibodies known as antiphospholipid antibodies. These antibodies can interfere with normal processes that regulate blood clotting, increasing the risk of blood clots forming in the arteries or veins. They may also contribute to pregnancy complications.
The exact cause of APS is not fully understood. It can occur on its own, known as primary APS, or alongside another autoimmune condition, particularly systemic lupus erythematosus (SLE), known as secondary APS.
Certain factors may increase the risk of developing blood clots in people with APS, including:
Autoimmune Conditions
APS can occur alongside other autoimmune conditions, particularly SLE. People with SLE are more likely to have antiphospholipid antibodies, although having these antibodies does not necessarily mean they have APS.
Antiphospholipid Antibody Profile
The risk of blood clots is higher in people with certain antiphospholipid antibody profiles, particularly when multiple types of antibodies are present, or when antibody levels remain persistently positive at high levels.
Other Risk Factors for Blood Clots
Factors such as smoking, prolonged immobility, obesity, surgery, pregnancy and the use of birth control pills can further increase the risk of blood clots in people with APS. Identifying and addressing these factors is an important part of reducing clotting risk and managing the condition.
Symptoms of Antiphospholipid Syndrome
APS may not cause noticeable symptoms unless a blood clot or pregnancy-related complication occurs. Symptoms vary depending on which blood vessels or organs are affected. Some people with antiphospholipid antibodies may never develop clinical features of APS.
Blood Clots in the Legs
A deep vein thrombosis (DVT) may cause swelling, pain, warmth or tenderness in one leg. Prompt medical assessment is important if these symptoms develop, as a blood clot can travel to the lungs and cause a pulmonary embolism. Sudden chest pain or difficulty breathing requires immediate emergency medical attention.Stroke or Transient Ischaemic Attack
Blood clots affecting the brain can cause a stroke or transient ischaemic attack. Symptoms may include sudden weakness or numbness, facial drooping, difficulty speaking or changes in vision. Seek emergency medical attention immediately if these symptoms occur, even if they resolve.Pregnancy Complications
APS may be associated with recurrent miscarriages, stillbirth, pre-eclampsia and restricted fetal growth. However, pregnancy loss and other pregnancy complications can have many causes and do not necessarily indicate APS. Assessment by a specialist can help determine whether APS may be contributing to these complications.
Skin Changes
Some people with APS develop a reddish-purple, net-like pattern on the skin known as livedo reticularis. A more irregular, broken or branching pattern is known as livedo racemosa. These skin changes can occur in APS but are not specific to the condition and may have other causes.Cardiovascular Complications
APS can affect the heart and blood vessels. Some people develop heart valve abnormalities, such as valve thickening or small deposits on the heart valve, which may affect their function. Blood clots in the coronary arteries can also cause a heart attack.
How Is Antiphospholipid Syndrome Diagnosed?
Diagnosing APS involves reviewing your medical history, clinical symptoms and blood test results. A positive antiphospholipid antibody test alone does not mean you have APS, as these antibodies can be present in people who have never experienced blood clots or APS-related pregnancy complications.
Diagnosis is generally based on a history of blood clots or specific pregnancy complications, together with persistently positive antiphospholipid antibody tests. Your doctor will interpret these findings in the context of your overall medical history and consider other possible causes of your symptoms.
Medical History and Clinical Assessment
Your doctor will review your medical history, including any previous blood clots, pregnancy complications and associated autoimmune conditions. A physical examination and assessment of other risk factors for blood clots will help guide further investigations.
Antiphospholipid Antibody Blood Tests
Blood tests are used to detect three main types of antiphospholipid antibodies: lupus anticoagulant, anticardiolipin antibodies and anti-beta-2 glycoprotein I antibodies. If an initial result is positive, repeat testing is generally performed at least 12 weeks later to determine whether the antibodies persist. This helps distinguish persistent antibody positivity from a temporary finding.
Imaging Tests
If a blood clot is suspected, imaging investigations may be recommended depending on the symptoms and the area affected. These may include ultrasound, CT or MRI scans to help identify the location and extent of a clot.
Assessment for Associated Conditions
Additional blood tests may be performed to assess for associated autoimmune conditions, particularly lupus, as well as other medical conditions or risk factors that may contribute to blood clotting.
How Do Rheumatologists Treat Antiphospholipid Syndrome?
Treatment for APS depends on your medical history, individual risk factors and whether you have experienced blood clots or pregnancy complications. People who have antiphospholipid antibodies without previous clinical events may not require the same treatment as those with established APS.
The main goals of treatment are to reduce the risk of blood clots and prevent recurrent complications.
Medical Management
Anticoagulant Medications
Anticoagulants help prevent blood clots from forming or recurring. Long-term treatment is generally recommended for people with APS who have experienced a blood clot.
Antiplatelet Medications
Low-dose aspirin may be recommended for selected individuals, depending on their antiphospholipid antibody profile and overall risk of blood clots.
Management of Associated Autoimmune Conditions
APS can occur alongside other autoimmune conditions, particularly SLE. When both conditions are present, treatment may be needed to control the underlying autoimmune disease and manage associated complications. Treatment will be tailored to your condition, disease activity and individual needs.
Pregnancy Planning and Management
For women with APS who are planning pregnancy or are already pregnant, treatment may include low-dose aspirin and injectable anticoagulants such as low-molecular-weight heparin (LMWH). The recommended treatment depends on your medical history, including whether you have previously experienced blood clots, pregnancy complications or both.
Careful planning and monitoring are important to reduce pregnancy-related risks and support maternal and fetal health. Warfarin is generally avoided during pregnancy because it can harm the developing baby. Your care may involve close coordination between your rheumatologist, obstetrician and other relevant specialists.
Long-Term Monitoring
Ongoing follow-up is important to monitor your condition, assess treatment effectiveness and review your risk of blood clots and other complications. If you are taking warfarin, regular blood tests are needed to monitor your international normalised ratio (INR) and guide dose adjustments.
Your treatment plan may also need to be reviewed before surgery, when planning pregnancy or if your medical circumstances change. This helps ensure that your treatment remains appropriate for your individual needs.
Living Well With Antiphospholipid Syndrome
APS is generally a long-term condition, but appropriate treatment and healthy lifestyle habits can help reduce the risk of complications. Managing cardiovascular risk factors and following your prescribed treatment plan are important parts of ongoing care.
Stay Physically Active
Regular physical activity supports cardiovascular health and overall wellbeing. Avoiding prolonged periods of immobility, particularly during long journeys or recovery from illness or surgery, may also help reduce the risk of blood clots.
Quit Smoking
Smoking increases the risk of cardiovascular disease and blood clots. Quitting smoking is particularly important for people with APS, who may already have an increased risk of blood clots.
Manage Other Health Conditions
Conditions such as high blood pressure, diabetes and high cholesterol can further increase cardiovascular risk. Keeping these conditions well-controlled, eating a balanced diet and maintaining a healthy weight can support your long-term health.
Follow Your Prescribed Treatment Plan
Taking medications as prescribed and attending follow-up appointments are essential for managing APS. Do not stop or change anticoagulant medication without medical advice, as doing so may increase the risk of blood clots or other complications.
Dr Poh Yih Jia
Senior Consultant Rheumatologist
Dr Poh Yih Jia is a senior consultant rheumatologist with more than 20 years of medical experience in
New Zealand and Singapore. Her clinical experience includes managing complex autoimmune diseases and
inflammatory arthritis, including antiphospholipid syndrome.
Her commitment to patient-centred care has earned her multiple accolades, including the Singapore Health
Quality Service Award and the Service with a Heart Award. She adopts an individualised, evidence-based
approach to rheumatological care, helping patients understand their condition and make informed
decisions about long-term management.
FAQs on Antiphospholipid Syndrome
Antiphospholipid syndrome (APS) is an autoimmune condition in which the immune system produces antiphospholipid antibodies associated with an increased risk of blood clots and certain pregnancy complications. The exact cause of APS is not fully understood. It can occur on its own or alongside another autoimmune condition, particularly systemic lupus erythematosus (SLE).
APS is generally a long-term condition that requires ongoing management. Although there is currently no cure, appropriate treatment and monitoring can help reduce the risk of blood clots and other complications.
Testing for APS may be considered for individuals who have experienced unexplained blood clots, recurrent blood clots or certain pregnancy complications, including recurrent pregnancy loss. Testing may also be appropriate for people with autoimmune conditions such as lupus, depending on their clinical history. A positive antibody test alone does not mean a person has APS.
Untreated APS can increase the risk of serious complications, including deep vein thrombosis, pulmonary embolism and stroke. It may also be associated with pregnancy complications, such as recurrent miscarriage and pre-eclampsia. The level of risk varies according to an individual’s medical history, antibody profile and other risk factors. Appropriate assessment and management can help reduce the risk of these complications.
There is currently no established way to prevent APS itself, as its underlying causes are not fully understood. However, people with APS can take steps to reduce their risk of blood clots by avoiding smoking, staying physically active and managing cardiovascular risk factors. Following prescribed treatment and attending regular follow-up appointments are also important for reducing the risk of complications.