People who have a higher genetic risk for stroke may benefit from maintaining good cardiovascular health, according to findings of a new study based on an analysis of the Atherosclerosis Risk in Communities (ARIC) Study.
Based on an analysis of data from more than 11,000 middle-aged adults who did not have a stroke at the start of the study and who were followed for a median of 28 years, the results of the study show that optimal cardiovascular health, as defined by the American Heart Association’s Midlife’s Simple 7, was linked to a lower risk of having a stroke over the course of a person’s lifetime. This was true for subgroups with different levels of polygenic risk score.
In a statement, Myriam Fornage, PhD, professor of molecular medicine and human genetics at the Institute of Molecular Medicine at The University of Texas Health Science Center at Houston, said, “We know that well-managed, modifiable risk factors, especially treatment of hypertension, can significantly lower a person’s risk of stroke.” “Our study showed that we may be able to lower the lifetime risk of stroke by changing other risk factors, and that keeping your heart healthy lowers the lifetime risk of stroke regardless of your genes, whether you have a high polygenic risk score or a low polygenic risk score. So, risk factors that can be changed are very important for preventing stroke.”
The current study was done by Fornage and his colleagues. It was paid for by the National Institute for Neurological Disorders and Stroke, which is part of the National Institutes of Health. The goal of the study was to find out how cardiovascular health could make up for the negative effects of high genetic risk on the lifetime risk of stroke among middle-aged patients in the US. With this in mind, the study was made to be an analysis of the ARIC study’s data. Using information from the ARIC study, researchers found 11,568 patients who had never had a stroke at the start of the study and included them in their analyses. These patients had a median age of 54 (IQR: 49–59) years, a median follow-up time of 28 (IQR: 19–30) years, a mean BMI of 26.8 (IQR: 24.0–30.3) kg/m2, 56% were women, and 23% were Black adults.
For the purpose of analysis, 3,000,000 single-nucleotide polymorphisms were used to calculate polygenic risk scores across the whole genome. Based on the number of stroke-related single-nucleotide polymorphisms, participants were put into low, intermediate, or high genetic risk groups. Cardiovascular health scores were based on how well people followed the guidelines in the American Heart Association’s Life’s Simple 7, which was recently updated and renamed Life’s Essential 8.
Overall, 2892 people were given a high genetic risk, 5783 people were given an intermediate genetic risk, and 2893 people were given a low genetic risk. Those with a high genetic risk were more likely to have parents with a history of stroke, high blood pressure, or diabetes. They also had a higher body mass index and total plasma cholesterol level (P0.001) than those with an intermediate or low genetic risk.
At 45 years old, people who have a high genetic risk, an intermediate genetic risk, or a low genetic risk have a remaining lifetime stroke risk of 23.2 percent (95 percent confidence interval: 20.8 to 25.5 percent), 13.8 percent (95 percent confidence interval: 11.7 to 15.8 percent), and 9.6 percent (95 percent confidence interval: 7.3 to 1.8 percent), respectively. At 45 years old, those with an inadequate, average, or optimal Life’s Simple 7 score for cardiovascular health had a 17.6% (95 percent CI: 15.6–19.6%), 13.4% (95 percent CI: 11.8–15.16%), and 9.8% (95 percent CI: 7.1–12.5%) remaining lifetime risk of stroke, respectively.
More research showed that people with a high genetic risk and low cardiovascular health scores had a higher chance of having a stroke in their lifetime, at 24.8%. (95 percent CI, 22.0-27.6 percent ). In contrast, those with a high genetic risk and good heart health had a 17.27% chance of having a stroke in their lifetime (95 percent CI, 10.88-23.66 percent ). Patients with low genetic risk and good cardiovascular health had the lowest lifetime risk of having a stroke (7.48 percent [95 percent CI, 3.09-11.87]). Researchers said that the results showed that people with good cardiovascular health had a 30–40% lower risk of having a stroke over their lifetime than people with bad cardiovascular health. This is equal to about 6 more years without a stroke.
“This is the first step in using genetic information to find people who may be more likely to have a stroke and to get people to change their lifestyles to prevent heart disease,” said Fornage. “This kind of study helps us see what could happen in the future. At this point, polygenic risk scores are not used in clinical settings. However, this could be the first step toward getting personalised risk information that can be used to make changes to lifestyle and health. Having good heart health is a key part of preventing strokes.”
The Journal of the American Heart Association published this study, called “Polygenic Risk, Midlife Life’s Simple 7, and Lifetime Risk of Stroke.”
