Large Study Reveals That 99% of Heart Attacks and Strokes Are Linked to Four Risk Factors

A study led by researchers at Northwestern University, involving data from more than 9 million adults in South Korea and the United States, found that exposure to at least one risk factor is almost certain before the onset of cardiovascular disease.

The long-term study showed that four major risk factors — high blood pressure, high cholesterol, high blood sugar, and smoking — preceded 99% of all major cardiovascular events.

High blood pressure emerged as the most common factor, with more than 93% of individuals who experienced a heart attack, stroke, or heart failure having a history of hypertension before developing the condition.

Even among women under the age of 60, more than 95% of cardiovascular events were associated with at least one of these risk factors.

Dr. Philip Greenland, the study’s senior author, emphasized that the goal is to focus on controlling these modifiable risk factors.

The findings also challenge claims that cardiovascular diseases are increasingly occurring in the absence of identifiable risk factors. Researchers suggest that previous studies may have overlooked risk levels that fell below conventional clinical diagnostic thresholds.

In a separate study, scientists from Mayo Clinic analyzed 1,474 cases of heart attacks among individuals aged 65 years or younger.

The results showed significant differences between men and women in the underlying causes of heart attacks. While 75% of cases in men were attributed to traditional artery blockage caused by atherosclerotic thrombosis, the figure dropped to 47% among women.

According to the study, 34% of heart attacks in women were linked to Type 2 myocardial infarction, which results from an imbalance between oxygen supply and oxygen demand in the heart muscle, often triggered by conditions such as anemia or infection.

Commenting on the findings, cardiologist Claire Raphael stated that the research highlights causes of heart attacks in women that have historically received insufficient attention. She warned that misunderstanding the root cause of a heart attack may lead to less effective—or even potentially harmful—treatment approaches.