A new study further highlights the importance of a healthy heart.

Researchers have concluded that middle-aged adults with no major risk factors for heart disease live longer and spend more of their senior years free of chronic illness.

The study – published today in the journal Circulation – represents the first attempt to assess how midlife cardiovascular health affects illness duration in later life.

Heart disease is the leading cause of death in the United States, killing around 610,000 people every year.

Risk factors for the condition include high blood pressure, high cholesterol levels, diabetes, being overweight or obese, an unhealthful diet, lack of exercise, and smoking.

According to a recent report from the American Heart Association, about 9 percent of adults in the United States aged 40 to 59 years have at least five “ideal” factors for good cardiovascular health.

For this latest study, Norrina Allen, Ph.D., assistant professor of preventive medicine at Northwestern University Feinberg School of Medicine in Illnois, and colleagues set out to determine how possessing favorable factors for cardiovascular health in midlife affects later-life health.

To reach their findings, the team analyzed data from the Chicago Health Association study. This study collected information on the health of thousands of individuals living in Chicago between 1967 and 1972. It has been following them through Medicare health records ever since.

At study baseline, participants were an average age of 44. Only about 5 percent had five favorable factors for heart health. They were non-smoking and free of diabetes, and had a healthy weight, blood pressure, and cholesterol levels.

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‘Never too late’ to reduce the risk

The researchers identified 17,939 study participants who had reached the aged of 65 without experiencing chronic illness.

Compared with adults who had at least two risk factors for heart disease, adults who had all five favorable factors lived an average of almost four years longer.

Additionally, adults who possessed all five favorable factors spent 22 percent fewer of their later years living with chronic illness.

They lived an average of 4.5 years longer without chronic illness and saved nearly $18,000 in Medicare costs.

Next, the researchers assessed how favorable cardiovascular factors in middle age might impact the risk of heart disease in later life.

They identified 18,714 adults who had not experienced a heart attack, stroke, or congestive heart failure before the age of 65.

The researchers found that adults who had all five favorable cardiovascular factors lived almost 7 percent longer than adults who had at least two cardiovascular risk factors. They also spent 46 percent fewer of their later years living with heart disease.

According to the researchers, their findings emphasize the importance of good heart health in midlife, but they stress that heart health should be a priority for all age groups.

"We need to think about cardiovascular health at all stages of life,” said Allen in a press statement.

"The small proportion of participants with favorable levels in their 40s is a call for all of us to maintain or adopt healthy lifestyles earlier in life. But risk factors and their effects accumulate over time, so even if you have risks it's never too late to reduce their impact on your later health by exercising, eating right, and treating your high blood pressure, cholesterol, and diabetes."

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