Picture of an Artery

Diabetes Mellitus/ High Blood Sugar

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Diabetes mellitus, often known as just ‘diabetes’, may lead to serious complications such as heart disease. In Singapore, one in every two persons who suffered a heart attack have diabetes. A person with diabetes is also four times more likely to suffer from heart failure than a person without diabetes.

The leading cause of death among people with diabetes is cardiovascular disease, hence it is very important for someone with diabetes to consult a Cardiologist for a cardiovascular risk assessment.

What is diabetes mellitus?

Insulin is a key hormone that allows cells to absorb sugar normally from the blood for conversion into energy. Diabetes mellitus arises when the body does not produce enough insulin or does not respond to it normally, leading to high blood sugar levels. Having high blood sugar levels will lead to symptoms and may cause long-term complications. If not properly managed, high blood sugar levels could lead to severe health issues — one of which is heart disease.

What are the different types of diabetes?
  • Type 1 Diabetes
    Type 1 diabetes is often hereditary and is the result of an autoimmune reaction that attacks any insulin-producing cells in the body. This type of diabetes is less common, and is usually discovered at a younger age.
  • Type 2 Diabetes
    Type 2 diabetes is very common in Singapore. It is a preventable disease that occurs when continuous high sugar intake causes your body to build up a resistance to insulin over time. It is often a result of poor diet and physical inactivity. It is also attributable to genetic factors. Type 2 diabetes makes up the majority of diabetes in Singapore.
  • Prediabetes
    Prediabetes is the precursor of Type 2 diabetes. Prediabetes means the blood sugar levels in the body are higher than normal, but not high enough to be diagnosed with Type 2 diabetes. If you have been diagnosed with prediabetes, you can delay the onset of diabetes through diet and lifestyle changes.
  • Gestational Diabetes
    Gestational diabetes occurs during pregnancy due to hormonal changes. Although blood sugar levels usually return to normal after delivery, there is a higher risk of developing type 2 diabetes in the future.
What are the symptoms of diabetes mellitus?

Prediabetes has no symptoms. Similarly, those with Type 1 or Type 2 diabetes may not have any symptoms, or they may have mild symptoms that are often unnoticed for some time. Some may experience symptoms or warning signs which may vary from person to person, such as:

  • Frequent urination
  • Increased thirst
  • Increased hunger
  • Unexplained weight loss
  • Fatigue
  • Blurred vision
  • Frequent infections (of the gums, skin, etc.)
What are the complications of diabetes?

Diabetes can affect many major organs in your body. Without proper treatment, serious complications may arise such as:

  • Cardiovascular disease including heart disease, peripheral arterial disease and stroke
  • Kidney damage (nephropathy)
  • Eye damage (retinopathy) leading to vision loss
  • Nerve damage (neuropathy) causing numbness in the extremities
  • Foot damage due to nerve damage and poor blood flow may lead to recurrent infection and amputation
  • Skin infections
How is diabetes treated?

The good news is that diabetes is treatable and often preventable. If you have diabetes or prediabetes, you may be able to avoid or delay other health complications by:

  • Knowing your numbers, including your blood sugar level, weight, blood cholesterol level and blood pressure
  • Adopting a healthy lifestyle, such as maintaining a healthy weight, regular exercise, having a healthy diet and managing stress. In fact, if you have prediabetes, you can delay or prevent the onset of diabetes by these measures.
  • Working with your doctor to manage the disease, which may include the use of medications
Should I get tested for diabetes?

You should consider getting tested for diabetes if you are over the age of 40, have a family member with diabetes, have high blood pressure, are physically inactive or overweight, or if you are a woman and ever been diagnosed with gestational diabetes, or if you have other risk factors for heart disease such as high cholesterol. All it takes is a simple blood test.

How does diabetes affect the heart?

Diabetes and heart disease often go hand in hand. Over time, high blood sugar can damage blood vessels and the nerves that control your heart. People with diabetes are also more likely to have other conditions that raise the risk for heart disease:

  • High blood pressure
    High blood pressure increases the force of blood through your arteries and can damage artery walls, causing it to harden. Having both high blood pressure and diabetes can greatly increase your risk for heart disease.
  • High LDL cholesterol
    High levels of bad cholesterol, or LDL, can form cholesterol plaques (a process called atherosclerosis) on the walls of the arteries. These plaques may cause narrowing and reduction of blood flow to your heart muscle.
  • High triglycerides
    Triglycerides are a type of fat in your blood. Together with high LDL, it can cause damage to the walls of the arteries.

Together with other risk factors such as family history, advanced age, smoking, overweight, physical inactivity, unhealthy diet and stress, these factors contribute to a higher risk of heart disease.

Heart disease in diabetics

Cardiovascular diseases commonly associated with diabetes are:

  • Coronary Artery Disease and Heart Attack
    High blood sugar levels damage the walls of the arteries and become susceptible to atherosclerosis (cholesterol plaque build-up). Atherosclerosis causes narrowings or blockages in the coronary arteries supplying blood to the heart muscle. The degree of atherosclerosis in people with diabetes are usually more extensive than people without diabetes. Severe narrowings may cause angina (or chest pain), decreased effort tolerance and may even trigger a heart attack. A heart attack is serious and may be life-threatening as parts of the heart muscle become damaged and unable to function.
  • Heart Failure
    People with diabetes are also more likely to get heart failure. Heart failure refers to the inability to pump blood well from weakened heart muscles, and this can lead to swelling in your legs and fluid in your lungs, making it hard to breathe. Heart failure tends to get worse over time, but early diagnosis and treatment can help relieve symptoms and stop or delay the condition from getting worse.
  • Diabetic Cardiomyopathy
    Diabetes itself can cause weakening of the heart muscles that is not caused by coronary artery disease. It can cause heart failure and may even trigger an abnormal and sometimes fatal arrhythmia (heart rhythm).
When should I see a cardiologist?

Besides seeing your regular doctor to help manage your diabetes, it is important to see a Cardiologist for a cardiovascular risk assessment because of the strong link between diabetes and heart disease. It is vital to consult a Cardiologist if you have diabetes and are experiencing symptoms of chest discomfort or shortness of breath.

Depending on your condition, you may be recommended to undergo other tests to check your heart health, which could include:

  • Electrocardiogram (ECG)
  • Exercise stress treadmill ECG
  • Echocardiography
  • Myocardial perfusion imaging (MPI)
  • CT coronary angiogram
  • Coronary angiogram
Take Care of Your Heart

These lifestyle changes can help lower your risk for heart disease or keep it from getting worse, as well as help you manage diabetes:

  • Have a healthy diet. Eat more fresh fruits and vegetables, lean meat, and whole grains. Avoid processed foods (such as chips, sweets, fast food) and avoid trans fat. Drink more water, fewer sugary drinks, and less alcohol.
  • Aim for a healthy weight. If you’re overweight, losing even a modest amount of weight can lower your triglycerides and blood sugar.
  • Get active. Physical activity makes your body more sensitive to insulin, which helps manage your blood sugar levels better. Physical activity also helps lower your risk of heart disease. Try to aim for 150 minutes per week of moderate-intensity physical activity, such as brisk walking.
  • Manage your ABCs:

A: Get a regular A1C test (a blood test to measure your average blood sugar over 2 to 3 months)

B: Try to keep your blood pressure below 140/90 mm Hg (or the target your doctor sets).

C: Manage your cholesterol levels.

s: Stop smoking or don’t start.

  • Manage stress. Stress can raise your blood pressure and can also lead to an unhealthy lifestyle. Stress increases the risk of heart diseases. If you find difficulty coping, please seek help from family, friends or professional experts.

Your doctor may also prescribe medicines that can help keep your blood sugar, blood pressure, cholesterol, and triglycerides close to your target levels.

How can we help you?

We offer consultation for a comprehensive range of cardiac diagnostic tests and treatment plans.

Dr Joshua Loh

Senior Consultant Interventional Cardiologist

Medical Director at Capital Heart Centre, Dr Joshua Loh has more than 15 years of experience in the field of cardiology.

He has extensive experience in the treatment of complex coronary and interventional procedures.