Wellmont CVA Heart Institute Cardiologist Dr. Harrison Turner. Photo provided by Wellmont.
Teens between the ages of 13 and 18 face a lot of decisions. To smoke or not? To exercise or not? To engage in sexual activity or not? To eat healthfully or not?
How they answer these questions, particularly those pertaining to diet, exercise and smoking, is of great importance to teenagers living in what’s known as the “stroke belt.”
According to a study published in the April 24, 2013, online issue of Neurology, the medical journal of the American Academy of Neurology, the teenage years may be a key period of vulnerability related to living in the stroke belt when it comes to future stroke risk.
More people have strokes and die of strokes in the southeastern area, known as the stroke belt, than in the rest of the United States. So far, research has shown that only part of the difference can be explained by traditional risk factors such as diabetes and high blood pressure. Previous studies have shown that people who are born in the stroke belt but no longer lived there in adulthood continue to have a higher risk of stroke, along with people who were born outside the stroke belt but lived there in adulthood.
The current study looked at how long people lived in the stroke belt and their ages when they lived there to see if any age period was most critical in influencing future stroke risk.
After adjusting for stroke risk factors, only living in the stroke belt during the teenage years was associated with a higher risk of stroke. People who spent their teenage years in the stroke belt were 17 percent more likely to have a stroke in later years than people who did not spend their teenage years in the stroke belt. Across all age periods, living in the stroke belt increased the risk about two-fold for African-Americans compared to Caucasians.
“The bottom line out of the study is that when you look at other factors that increase your stroke risk, that explains most of the difference. The typical factors tend to relate to blood pressure, tobacco use and dietary activities, in other words, people eating the wrong foods, high salt diets, elevated cholesterol values and triglyceride values and a higher risk of obesity,” said Dr. Harrison Turner, a cardiologist with the Wellmont CVA Heart Institute.
“What does this study try to answer? When people do move to the stroke belt, they do have a higher risk because they take on the behaviors and lifestyle of the people who live here. That would explain why, if I move here from Maine and I start salting my food heavily, I pick up a few extra pounds, my blood pressure rises, those are things that increase my stroke risk,” he said.
Harrison said when the different age groups and risk factors were studied in the 24,544 participants, researchers found something interesting.
“The thing they found curious and really not explained by other factors would be the people who lived in the stroke belt during their adolescent years — whether they stayed here or moved off in that 13 to 18 age group — they had a somewhat higher stroke risk than people who didn’t live here,” he said.
“Seventeen percent in the big spectrum of things is not a big deal,” he said. “It’s one of those things that remained a bit unexplained, and I think that when you try to say out of all these factors ... that when they took all the other variables they would normally consider for stroke, they had this unexpected mild increase in stroke for people who lived in the stroke belt during their adolescence. When you sort through all this, their guesstimate is that an awful lot of your lifestyle decisions that you make are made during those times.”
The stroke belt is typically defined as an 11-state region consisting of Alabama, Arkansas, Georgia, Indiana, Kentucky, Louisiana, Mississippi, North Carolina, South Carolina, Tennessee and Virginia. Among the challenges facing Tennesseans are a sedentary lifestyle, high rates of cancer and cardiovascular deaths, a high infant mortality rate and a high prevalence of low birth weight.
According to the study author Virginia J. Howard, of the School of Public Health, University of Alabama at Birmingham and a member of the American Academy of Neurology, the study suggests that strategies to prevent stroke need to start early in life.”
“Many social and behavioral risk factors, such as smoking, are set in place during the teenage years, and teens are more exposed to external influences and gain the knowledge to challenge or reaffirm their childhood habits and lifestyle,” she said.
Education needs to focus on our middle- and high-schoolers, Turner said.
“This tells us there’s an important window, that education and teaching is most likely to be beneficial. Those are times that are decision-making times for maturing adolescents,” he said. “The assumption is that when we have behaviors that influence us — to smoke or not to smoke, to be slugs or stay fit and physically active — a lot of those lifelong behaviors get established during that time.”
Data came from the REasons for Geographic And Racial Differences in Stroke (REGARDS) study, a national random sample of the general population with more people selected from the stroke belt. The study involved 24,544 people with an average age of 65 who had never had a stroke at the start of the study, with 57 percent currently living in the stroke belt and 43 percent from the rest of the country.
The study tracked each person’s moves from birth to present, with some people moving into or out of the stroke belt. The participants were then followed for an average of 5.8 years. During that time, 615 people had a first stroke.
“It doesn’t surprise me that we have a stroke belt because of the increased risk factors that this territory has,” Turner said. “But it does surprise me that adolescence is an important time. It’s common sense if you think about it, but it wouldn’t be something that’s intuitive.”