Hidden Risks of Diabetes: What Is Silent Heart Disease?

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Advances in the diagnosis and treatment of heart attacks have saved lives and improved prevention efforts. Patient education typically covers the classic symptoms, as well as the unusual symptoms (which are more common in women).

Unfortunately, symptoms do not precede or accompany every heart attack. At least 15 percent of myocardial infarctions (the medical term for heart attacks, also called MIs) are “silent” and are only discovered by tests like electrocardiograms (ECGs) at routine office visits.

Diagnosis of a past silent MI surprises both the patient and healthcare providers, and it increases the risk for additional heart disease. That makes identification of these events crucial to long-term preventive care.

Heart risks in people with diabetes: they don’t feel it

People with diabetes have an even greater risk of silent heart disease, which is more relevant than ever because people with silent MIs are three times more likely to die than people without an MI. Heart attacks result from blockages in the heart’s own blood vessels. Generally, the damage is caused by high cholesterol that clogs arteries and form clots, or sometimes by inherited blood vessel weaknesses. In people with diabetes, nerve damage from excess sugar affects vision and limb sensations, and it also injures the nerve system that helps the heart.

When this autonomic nerve system fails, pain from blood vessel spasms isn’t felt. More important, symptoms from the heart attack don’t alert someone with diabetes to get help, so repeated and lasting heart damage can occur.

The risk of blood vessel damage is two to four times greater with diabetes. Two causes of that damage—high blood pressure and diabetes-related nerve damage—are primary risks for silent heart damage. However, silent MIs can occur even in people with diabetes whose high blood pressure or high cholesterol are treated with medicine and even in those without known heart disease.

Finding and preventing silent heart damage: no simple solution

Unfortunately, identifying people with diabetes who have silent heart damage isn’t as simple as just checking for risks. Screening by factors like age, weight, or lifestyle doesn’t specifically find patients with past or ongoing damage.

The American Diabetes Association, in its 2017 guidelines, does suggest measuring blood pressure at every medical appointment and recommends an annual assessment of heart health, including an ECG.

Silent MIs appear, during and for a short while after the event, as changed Q waves on ECGs. An abnormal result in a patient with diabetes should then trigger more cardiac tests (like angiograms or troponin levels) to check blood vessel health and markers of MIs despite the lack of symptoms.

Taking action: standards for patients and providers

If you have diabetes, you already manage multiple health issues every day, so the importance of basic cardiac care could become overlooked as a lower priority. Certainly, avoiding sugar spikes is key to reducing nerve damage that can hide heart problems.

Other ways you can protect nerves and strengthen the heart are:

  • exercising and losing weight
  • avoid smoking
  • lowering blood pressure and cholesterol through diet or medications
  • keeping appointments to check blood pressure or blood sugar levels

MI symptoms can be missed or unrecognized in diabetes even if they aren’t silent. You and your caregivers should learn to recognize “whisper symptoms” — odd sensations during activities that are usually easy — and get help when they occur. The National Institutes of Health has more suggestions and free resources about preventing and recognizing diabetic heart disease, too.