Diabetes is a disease in which your blood glucose, or blood sugar, levels are too high. Glucose comes from foods you eat. The cells of your body need glucose for energy. A hormone called insulin helps the glucose get into your cells.

With type 1 diabetes, your body doesn't make insulin. With type 2 diabetes, your body doesn't make or use insulin well. Without enough insulin, glucose builds up in your blood and causes high blood sugar levels.

Diabetic heart disease is a term for heart disease in people who have diabetes. If you have diabetes, you are much more likely to develop heart disease or have a stroke than people who don't have diabetes. And you may start having these problems at a younger age.

Over time, the effects of high blood sugar from diabetes can include damage to the blood vessels and nerves in your heart. This damage increases your chance of developing heart diseases, including:

• Coronary artery disease (CAD). It happens slowly as a sticky material called plaque builds up in the arteries that supply your heart muscle with blood.
• Heart failure. With this condition, your heart can't pump enough oxygen-rich blood to meet the needs of your body.
• Cardiomyopathy. This is a group of diseases in which the heart muscle may become thick or stiff.

Diabetes puts you at serious risk for heart disease. It also makes you more likely to develop other conditions that raise your risk even more, including:

• High blood pressure
• High blood levels of LDL "bad" cholesterol
• High triglycerides (a type of fat in your blood) with low blood levels of HDL "good" cholesterol

Your risk for heart disease is also higher if you

• Are male
• Smoke
• Have obesity
• Have too much belly fat around your waist, even though you're at a healthy weight:
  • For men, that's a waist more than 40 inches
  • For women, that's a waist more than 35 inches
• Have a family history of heart disease
• Have chronic kidney disease

In the early stages, heart disease usually doesn't have any symptoms. But if your heart disease worsens, you can have symptoms. Your symptoms will depend on the type of heart disease you have. They might include:

• Shortness of breath
• Fatigue
• Dizziness or fainting
• Arrhythmia (problem with the rate or rhythm of your heartbeat)
• Swollen feet and ankles
• Chest pain

It's important to know that people with diabetes may not feel chest pain. That's because diabetes can damage the nerves in your heart. If you have any symptoms that could be heart disease, talk with your health care provider.

To find out if you have diabetic heart disease, your provider will:

• Ask about your medical history, including your symptoms and other health conditions you may have
• Ask about your family history, to find out if you have relatives who have or had heart disease
• Do a physical exam
• Likely run some tests to help understand your personal risk for heart disease, including:
  • Blood tests to check your cholesterol, triglycerides, and blood sugar levels
  • A blood-pressure check
  • Heart tests, if needed

Depending on your risk level, your provider may send you to a cardiologist (a doctor who specializes in heart diseases) for care. If you do have heart disease, treatment will depend on the type of heart disease you have.

You may be able to prevent heart disease or keep it from getting worse by working with your provider to:

• Control your blood sugar levels
• Manage other conditions you may have that can raise your risk for heart disease
• Take any medicines your provider prescribed
• Make heart-healthy habits part of your daily life
• Follow a healthy eating plan for diabetes

NIH: National Institute of Diabetes and Digestive and Kidney Diseases