This Calculator Shows the Biggest Risk Factors for Heart Disease. It Might Surprise You.

(Illustration by Barron’s)

Key Points

• The American Heart Association’s revamped risk calculator identifies smoking, diabetes, and high blood pressure as major heart disease risk factors.
• A 70-year-old male smoker has a 14.9% chance of cardiovascular disease in the next decade, compared with 11.4% for a nonsmoker.
• Kidney disease is a warning sign for heart disease, as high blood pressure damaging kidneys probably also affects the heart and brain.

Who knew? Kidney disease is one of the warning signs for heart disease.

If you want to lower your risk of total cardiovascular disease, including clogged arteries and heart failure, take a look at the revamped risk calculator from the American Heart Association.

By playing with the different inputs, you can get a better idea of the risk factors. The calculator isn’t designed to tell you how much your heart disease risk will decline if you improve these factors—that is a different exercise—but it will tell you if you’re heading in the right direction.

Some of what you will learn isn’t too surprising. Smoking raises risks dramatically. I put in healthy inputs for all of the various factors for a 70-year-old male, including blood pressure, cholesterol levels, and kidney function. If this man has had a cigarette in the past 30 days, the American Heart Association calculator says he has a 14.9% chance of developing cardiovascular disease in the next decade. If he isn’t a smoker, he has an 11.4% chance.

“Smoking is absolutely the No. 1 thing we should address,” says Dr. Ashish Sarraju, who specializes in preventive cardiology at the Cleveland Clinic. “There is almost nothing we can do that benefits a person as much as quitting smoking.”

Smoking raises your blood pressure while leaving you more likely to develop blood clots, inflammation, and plaque formation in your arteries, Sarraju says.

Diabetes is another biggie. It makes you prone to high blood pressure, high cholesterol, and high insulin levels, all risk factors for heart disease.

Let’s take that same 70-year-old man and tell the calculator that all of his other measurements are healthy, but he has diabetes. He now has a 16.6% chance of heart disease. If he didn’t have diabetes, the risk is 11.4%.

Another key input in the calculator is your systolic blood pressure. Hypertension damages your heart, brain, and kidneys, and increases plaque formation in your blood vessels.

Once again, let’s return to that 70-year-old. If his systolic measure rises from 120 to 160, his predicted risk of heart disease rises from 11.4% to 15.6%.

What if he uses blood pressure medications? The calculator looks at that, too. If our 70-year-old with systolic pressure of 120 is using blood pressure meds, he has a 15% chance of heart disease versus the 11.4% chance for someone who doesn’t take meds.

What’s going on here? Are you better off not taking blood pressure medications? Not at all. The risk calculator reckons that someone on blood pressure medications has probably had hypertension for years, and that is why it increases predicted risk. Using medication to control your blood pressure is highly advised if you can’t control it through lifestyle changes.

Indeed, the pernicious effects of hypertension are one reason the calculator views kidney disease as a warning sign for heart disease. If your kidney is losing the ability to filter your blood as efficiently, as measured by your estimated glomerular filtration rate, or eGFR, it is likely that your heart and brain, along with your kidneys, are being damaged by high blood pressure.

Next comes cholesterol. The calculator examines both total cholesterol and HDL cholesterol, the so-called good cholesterol.

The calculator also asks for your body-mass index, or BMI, a way to measure whether your body weight is at healthy levels for your height.

High BMI in itself isn’t a risk factor for heart disease. That is because a minority of obese people are metabolically healthy and don’t have an elevated risk of heart disease. Meanwhile, a minority of normal-weight people are metabolically unhealthy and do have a higher risk of heart disease.

The bottom line? While maintaining a healthy weight isn’t a sure cure, it does make you less likely to get cardiovascular disease.

The biggest risk factors of all for heart disease are two things you can’t control: your age and your sex. The older you are, the more likely you are to have a cardiovascular event in the next decade. And men are more likely to have heart disease than women. If you increase your age in the American Heart Association calculator, your risks soar.

That is the bad news. The good news is that while heart disease remains the country’s top killer, deaths from it have dropped in recent decades as smoking rates declined. Also, doctors have gotten powerful new drugs to treat hypertension, diabetes, obesity, and high cholesterol levels.

“We know that aging isn’t something we can change,” Sarraju says. “We’re going to do best so that you die with heart disease not because of heart disease.”

Write to Neal Templin at neal.templin@barrons.com