Healthy lifestyle can reduce genetic heart attack risk

Following a healthy lifestyle can cut in half the probability of a heart attack or similar events even among those at high genetic risk, say researchers, including one of Indian-origin.

"The basic message of our study is that DNA is not destiny," said study senior author Sekar Kathiresan, Director, Center for Human Genetic Research at Massachusetts General Hospital in the US.

The study published in the New England Journal of Medicine suggests that lifestyle factors -- not smoking, avoiding excess weight and getting regular exercise -- significantly alter the risk of coronary events.

"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, who is also Associate Professor of Medicine at Harvard Medical School, said.

"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," Kathiresan added.

The researchers analysed genetic and clinical data from more than 55,000 participants in four large-scale studies. 

Each participant in the analysis was assigned a genetic risk score, based on whether they carried any of 50 gene variants that previous studies associated with elevated heart attack risk. 

Based on data gathered when participants entered each study, the investigators used four lifestyle factors -- no current smoking; lack of obesity, defined as a body mass index less than 30; physical exercise at least once a week, and a healthy dietary pattern -- to determine a lifestyle score, whether participants had a favourable (three or four healthy factors), intermediate (two factors) or unfavourable (one or no healthy factors) lifestyle.

The researchers found that a higher genetic risk score significantly increased the incidence of coronary events -- as much as 90 per cent in those at highest risk.

Each healthy lifestyle factor reduced risk, and the unfavourable lifestyle group also had higher levels of hypertension, diabetes and other known risk factors upon entering the studies, the study found.