A huge international study has found that heart attacks, strokes, and heart failure almost never happen without warning.
The research showed that more than 99% of people who later developed one of these serious conditions already had at least one well-known risk factor. The findings were published in the Journal of the American College of Cardiology.
Heart disease is the leading cause of death around the world. It develops over many years as damage builds up in the heart and blood vessels. Although some people believe these events strike without any warning, the new research suggests that this is rarely the case.
The study was led by researchers from Northwestern Medicine in the United States and Yonsei University in South Korea. The team analyzed health records from more than 9 million adults in South Korea and nearly 7,000 adults in the United States. Some participants were followed for as long as 20 years, allowing the researchers to see which health problems appeared before major heart events.
The researchers focused on four common risk factors that doctors can measure and treat. These were high blood pressure, high cholesterol, high blood sugar or diabetes, and tobacco use. According to the American Heart Association, even mildly raised levels of blood pressure, cholesterol, or blood sugar can increase the risk of heart disease over time.
The results were striking. More than 99% of people who later had a heart attack, stroke, or heart failure already had at least one of these risk factors before becoming seriously ill. More than 93% had two or more risk factors, showing that many people had several warning signs years before their heart event.
High blood pressure was the most common problem. It affected more than 95% of participants in South Korea and more than 93% of participants in the United States who later developed cardiovascular disease. Even women younger than 60 years old, who are often considered to have a lower risk, usually had at least one of these warning signs before becoming ill.
The researchers also looked at people with more severe health problems, including very high blood pressure, very high cholesterol, diabetes-level blood sugar, and current smoking. Even in this group, at least 90% had one or more of these major risk factors before suffering a serious heart condition.
Senior author Dr. Philip Greenland of Northwestern University said the findings show that preventing heart disease should focus on controlling known and treatable risk factors. Rather than searching for rare causes, doctors and patients should pay close attention to blood pressure, cholesterol, blood sugar, and smoking, because improving these factors could prevent many heart attacks and strokes.
The study cannot prove that these risk factors directly caused every heart event, but it strongly shows that they are present in almost everyone who later becomes seriously ill.
The findings highlight the importance of regular health checks and early treatment. Managing blood pressure, cholesterol, diabetes, and smoking may greatly reduce the risk of life-threatening heart disease in the future.
If you care about heart disease, please read studies that herbal supplements could harm your heart rhythm, and how eating eggs can help reduce heart disease risk.
For more health information, please see recent studies that apple juice could benefit your heart health, and results showing yogurt may help lower the death risks in heart disease.
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