How Diabetes Increases the Risk of Heart Attack and Stroke

Excess sugar in the bloodstream damages tissue and impairs the inner lining of arteries, setting the stage for dangerous cardiovascular complications.

How Excess Blood Sugar Damages Arteries

The fundamental link between diabetes and cardiovascular disease rests on tissue injury caused by excessive sugar circulating in the bloodstream. According to Canadian cardiologist David Fitchett of St. Michael’s Hospital in Toronto, speaking at a congress held by the Sociedade Brasileira de Cardiologia do Estado de São Paulo (SOCESP) in May 2016, the internal lining of the artery, known as the endothelium, loses its protective properties and permits abnormal cells to enter the vessel.

This endothelial dysfunction starts the formation of atherosclerosis, or fat plaques. Fitchett explains that the metabolic state of diabetes alters fat particles chemically, making them toxic to artery walls. These toxic particles are absorbed by cells inside the wall, ultimately killing them and creating a pool of fat that forms an atherosclerotic plaque.

Furthermore, blood platelets in diabetes patients are more sticky, which increases the likelihood of blockages at the site of the abnormal endothelium. When combined with increased inflammation, this state raises the risk that the arterial lining will rupture and expose blood to the underlying fat. That exposure triggers clots that can obstruct coronary arteries, causing a heart attack, or cerebral arteries, causing a stroke.

Atypical Heart Attack Symptoms in Diabetes Patients

Cardiovascular events in individuals with diabetes do not always present with classic warning signs. According to Dr. David Fitchett, roughly 20% to 30% of patients with diabetes experience atypical symptoms during a heart attack.

Muitas vezes, eles apenas se queixam de falta de ar ou tontura. Por isso, muitos não se dão conta de que estão tendo um ataque cardíaco. Na verdade, é fundamental que o paciente com diabetes faça acompanhamento cardiológico frequente David Fitchett

Broader Cardiovascular and Metabolic Complications

The risk profile extends beyond heart attacks and strokes. Cardiologist Rafaela Penalva, who holds a doctorate in sciences from the University of São Paulo (USP) and the Instituto Dante Pazzanese de Cardiologia (IDPC), notes that diabetes multiplies cardiovascular event risks significantly. Writing on the occasion of the National Diabetes Day in June, she detailed how chronic hyperglycemia causes inflammation, endothelial dysfunction, vascular rigidity, and direct harm to nerves and organs.

Associated conditions linked to the metabolic disease include heart failure, microvascular and macrovascular complications, and fatty liver disease, known as steatosis hepatica. According to data cited from the IBGE and the International Diabetes Federation, Brazil counts approximately 20 million people with diabetes, ranking the country sixth globally in incidence.

Long-Term Risks and Prevention Challenges

Uncontrolled diabetes over the long term leads to severe systemic damage. Dr. Rafaela Penalva warns that chronic high blood sugar results in blindness, kidney failure requiring dialysis or transplantation, and amputations linked to diabetic foot ulcers and infections.

Managing these risks often requires abandoning sedentary routines and poor diets maintained for decades. Fitchett emphasizes that establishing healthy habits must start early through education in schools, as breaking lifelong patterns remains a major hurdle for adult patients.