Diabetes and heart disease

Summary

Diabetes, especially type 2, is one of the cardiovascular risk factors that can be controlled. People with diabetes are more likely to develop heart attack, stroke and heart failure, often earlier than others. The good news is that the risk falls a great deal when all the factors are treated together, not just blood sugar.

Why diabetes damages the heart

• High blood sugar over the years damages the wall of the blood vessels and speeds up atherosclerosis (plaques in the arteries).
• Diabetes often comes with high blood pressure, abnormal cholesterol and overweight — each one adds to the risk.
• Nerve damage can make the pain of a heart attack weaker or atypical.
• The heart muscle can be damaged directly (diabetic cardiomyopathy), leading to heart failure.
• Diabetes also damages the kidneys, and kidney disease raises the risk to the heart even further.

Even when blood glucose is controlled, the risk does not fully disappear — that is why all the factors need to be controlled.

The numbers that are checked

• Blood pressure: an individual target; for most people who tolerate it, about 120–129 mmHg systolic, without going below 120 (see arterial hypertension).
• LDL cholesterol: the target depends on risk and is often lower than in the general population (see diabetes and cholesterol).
• Triglycerides: above 150 mg/dL is considered high.
• Glucose and HbA1c: the target is set individually; often around 7%, less strict in the elderly or those with many illnesses.
• Weight and waist circumference
• Kidney function: creatinine with eGFR and the urine albumin/creatinine ratio (see kidney function tests).

What heart checks are done

The cardiologist and endocrinologist decide together, according to age, how long you have had diabetes and any other conditions. They usually include:

• a visit with cardiovascular risk assessment
• an ECG
• echocardiography, when there are symptoms, a murmur, high blood pressure with suspected wall thickening, or suspected heart failure
• Doppler of the neck or leg vessels, when indicated
• checks of the feet and eyes for other complications

When there are no symptoms, many tests are not done automatically; the assessment is personalized.

Treatment that protects the heart

• Lifestyle: a balanced diet, weight loss when overweight, at least 150 minutes of physical activity a week, stopping smoking, limiting alcohol.
• Statins lower LDL and the risk of heart attack; many patients with diabetes take them.
• Blood pressure medicines (often ACE inhibitors or ARBs, which also protect the kidneys).
• Diabetes medicines with proven benefit for the heart and kidneys — SGLT2 inhibitors and some GLP-1 receptor agonists. The choice is the doctor’s, according to other conditions.
• Aspirin is not given automatically as prevention to everyone: this is decided only by the doctor, weighing the risk of bleeding.

Do not stop or change any medicine on your own.

Signs not to ignore

• new dyspnea on exertion or when lying down
• swelling of the ankles
• unusual fatigue or reduced ability to exert yourself
• pain or tightness in the chest, neck or jaw
• palpitations or dizziness

Tell the doctor even when they feel mild: in people with diabetes they may be the only sign.