While other states have seen significant drops in rates of deaths related to heart disease, many southern states lag behind the rest of the nation.

As a whole, deaths caused by heart disease are slowly dropping in the United States. However, certain areas of the country are still behind in heart health.

According to research published Monday in the American Heart Association (AHA) journal Circulation, several Southern states below the Mason-Dixon line experience more heart disease-related deaths compared with the rest of the country.

Heart disease deaths peaked in the late 1970s and early 1980s. They have been declining since the beginning of the 21st century.

Some areas fare better than others. However, heart disease remains the number one killer in the United States, as the prevalence of risk factors continues to rise.

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Researchers used death certificate data on Americans aged 35 years and older from 1973 to 2010.

With that, they were able to map out where heart disease continues to be problematic.

The study’s lead author, Michele Casper, Ph.D., an epidemiologist at the Centers for Disease Control and Prevention’s (CDC) Division for Heart Disease and Stroke Prevention in Atlanta, Georgia, says the largest pockets of heart disease-related deaths have shifted since the 1970s.

During the 1970s, high death rates impacted the Northeast through parts of Appalachia and into the Midwest. Coastal areas in North Carolina, South Carolina, and Georgia also had high-rate clusters.

While decreases in heart-related deaths were higher than 80 percent in some counties in the northern states, the lowest rates of improvement — 9.2 percent in one county — were in Alabama, Mississippi, Louisiana, Arkansas, Oklahoma, and Texas.

“These findings provide local communities with important historical context regarding their current burden of heart disease, and emphasize the importance of local conditions in heart disease prevention and treatment efforts,” Casper said in a press release.

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The study, however, didn’t address why the rates have changed.

However, death rates may have been impacted by social and economic conditions, public health policies, and increased opportunities for physical activity. Also, fewer environments that permit smoking, and access to healthy foods and healthcare may have also played a part.

“Despite the overall decline in heart disease death rates, heart disease remains the leading cause of death in the United States, as well as one of the most widespread and costly health problems facing the nation,” Casper said. “More than 600,000 people die of heart disease in the United States every year. That’s one in every four deaths.”

Heart disease is caused by numerous overlapping risk factors. These include diabetes, hypertension, high cholesterol, smoking, and family history.

“The process can start at a very young age. These things all work in combination. They are not isolated,” Dr. Qasim Cheema, a cardiologist in Mississippi who wasn’t associated with the study, told Healthline. “Heart disease is out there. It’s everywhere. It will affect everyone, maybe not personally, but it could affect a loved one.”

He should know. His cousin died of a heart attack at the age of 32.

That also illustrates that the AHA study may have excluded younger people who died of heart disease.

According to the AHA, about 12 percent of men and 10 percent of women aged 20 to 39 years suffer from cardiovascular disease.

Mississippi, according to America’s Health Ratings, continues to be plagued by decreasing levels of physical activity, high rates of smoking, and obesity rates higher than the rest of the country. All of these factors contribute to heart disease.

While Cheema says cardiology is one of the most evidenced-based practices, he says there’s still much to learn about protecting the hearts of Americans.

“There’s still a lot we don’t know yet,” he said. “This is all still new.”

While medical technology may extend the lives of people with heart disease, the ultimate goal is to help people lower their risk factors. This includes controlling diabetes, eating healthier, exercising regularly, and taking medications as prescribed.

The message, Cheema said, can be raised through public health campaigns and education on how people can lower their chances of a premature death.

“Prevention is key,” he said. “We have to invest in this. We need more awareness.”

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