Four common factors appear prior to 99% of heart attacks and strokes

A large analysis of health records from South Korea and the United States reports that 99 percent of heart attacks and strokes were preceded by at least one common risk. The main signal held across ages and in both countries.

Those risks are high blood pressure, high cholesterol, high blood sugar, and tobacco use. These conditions fall under cardiovascular disease, illnesses that involve the heart and blood vessels.

Studying heart health risks

The work was led by Hokyou Lee, MD, PhD, at Yonsei University College of Medicine in Seoul (SNU). His research focuses on cardiovascular risk and prevention in populations.

Researchers tracked two cohorts, one drawn from a national insurance database in Korea and one from a diverse research cohort in the United States. Together, the records spanned more than 9 million adults and many first cardiac or neurologic events.

Among people who eventually had a first event, the Korean database counted 601,025 outcomes while the U.S. cohort recorded 1,188. The team then checked whether any of the four risks appeared at any clinic visit before the event.

They did not require a formal diagnosis to count risk, which better reflects everyday care. Many people carry numbers that are not ideal for years before disease appears.

The four heart risk factors

The study counted hypertension, chronically high blood pressure that strains the heart and blood vessels, as systolic 120 mm Hg or diastolic 80 mm Hg. It also counted people taking blood pressure medicine as having this risk.

Cholesterol was counted as total cholesterol at or above 200 milligrams per deciliter or use of a lipid lowering drug. The team also tracked fasting glucose, blood sugar measured after not eating for at least 8 hours, at 100 milligrams per deciliter or higher.

Past or current tobacco use qualified as the fourth risk. Elevated blood pressure showed up most often before events, while smoking appeared least often.

Doctors often focus on LDL cholesterol, the particle that most strongly drives plaque buildup in arteries. Lowering LDL cholesterol reduces future heart attack risk in a stepwise fashion.

When non-optimal is dangerous

The thresholds were intentionally modest to catch risk early. This approach reflects primordial prevention, which focuses on stopping risk factors from taking root long before they can trigger disease.

Damage to arteries builds slowly when blood pressure, glucose, or lipids sit above ideal levels. The body handles small shifts for a while, but steady exposure over years increases strain and raises the chances of a serious event.

Many people move through life with numbers that are not alarming yet still fall outside the safest range. Those small gaps create pressure that grows with time and eventually weakens the heart and blood vessels.

Routine checkups and labs matter because they reveal these early shifts. Correcting issues while they are still mild can change long term outcomes and prevent a future emergency.

Women under 60 are not exempt

In women younger than 60, heart failure and stroke still had more than 95 percent of events preceded by at least one nonoptimal risk. That means early prevention remains relevant even in the lowest risk female age group.

This finding undercuts the belief that midlife events often strike without warning in otherwise healthy women. It highlights the value of early blood pressure, cholesterol, and glucose management across adulthood.

Gap between risk and care

An accompanying study noted that people typically had several clinic visits before their events, which meant there were many chances to check and manage their health risks. Those visits represented opportunities to test, treat, and follow through.

Blood pressure control, cholesterol lowering, smoking cessation, and glucose management are all within reach today. Therapeutic combinations and steady lifestyle changes produce the largest gains.

Cardiovascular disease remains the top cause of death in the United States, with 941,652 deaths in 2022, according to the American Heart Association (AHA). The scale of suffering underlines why early detection and treatment of these four risks is urgent.

The new results do not claim that every event can be prevented. They do indicate that stronger control of four common risks could avert large numbers of tragedies.

Recognizing heart health risks

This was an observational study, research that follows people without assigning treatments, so it reveals patterns but cannot prove cause. It still offers clear direction on where prevention should focus.

The cohorts came from different settings and cultures, and visits were spaced over years. Even with those differences, the central signal stayed consistent across groups and outcomes.

Future work will test ways to reach people earlier and keep numbers controlled over time. Primary care access, community programs, and easy to use medicines will all play key parts.

The study is published in the Journal of the American College of Cardiology.

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