AHA 2016: Healthy lifestyle may decrease coronary artery disease risk in adults with high genetic risk
Adults with a high genetic risk for coronary artery disease had a nearly 50 percent lower relative risk of coronary artery disease if they adhered to a favorable lifestyle compared with those who had an unfavorable lifestyle, according to an analysis of three prospective cohorts and a cross-sectional study.
Lead researcher Amit V. Kehra, MD, of Massachusetts General Hospital, and colleagues published their results online Nov. 13 in the New England Journal of Medicine.
The findings were simultaneously presented at the American Heart Association Scientific Sessions in New Orleans.
“The basic message of our study is that DNA is not destiny,” Sekar Kathiresan, MD, the study’s senior author and director of the Center for Human Genetic Research at Massachusetts General Hospital, said in a news release. “Many individuals—both physicians and members of the general public—have looked on genetic risk as unavoidable, but for heart attack that does not appear to be the case.”
The researchers noted that more than 50 independent loci associated with the risk of coronary artery disease have been identified since 2007. For this analysis, they derived a polygenic risk score from up to 50 single-nucleotide polymorphisms and used it to quantify genetic risk for 55,685 adults.
The adults participated in the cross-sectional BioImage Study as well as three prospective studies: the Atherosclerosis Risk in Communities (ARIC) study, the Women’s Genome Health Study (WGHS) and the Malmö Diet and Cancer Study (MDCS).
The researchers considered people to have a favorable lifestyle if they had three of the following: did not smoke, were not obese, participated in physical activity at least once per week and had a healthy diet pattern. People with an unfavorable lifestyle had one or none of those factors.
They found that participants in the highest genetic risk quintile had a 91 percent higher relative risk of incident coronary events compared with those in the lowest genetic risk quintile. They defined coronary events as MI, coronary revascularization and death from coronary causes.
In addition, adults with a favorable lifestyle had a substantially lower risk of clinical coronary events and subclinical burden of coronary artery disease compared with those with an unfavorable lifestyle. The association was similar for all genetic risk categories.
A favorable lifestyle was associated with a 46 percent lower relative risk of coronary events compared with an unfavorable lifestyle among participants in the highest genetic risk category.
The researchers cited a few limitations of the study, including that they could not ascertain a causal relationship between lifestyle factors and the risk of coronary events. They also mentioned that the four studies had different ways of assessing lifestyle at baseline. In addition, the polygenic risk score might have been more useful if the researchers included more validated genetic polymorphisms.
“Some people may feel they cannot escape a genetically determined risk for heart attack, but our findings indicate that following a healthy lifestyle can powerfully reduce genetic risk,” Kathiresan said in a news release. “Now we need to investigate whether specific lifestyle factors have stronger impacts and conduct studies in more diverse populations, since most of the participants in these studies are white.”