Healthy lifestyle ‘cuts stroke risk’ — even in people with high genetic risk

Keeping a healthy lifestyle can reduce people’s chance of having a stroke even if they are at high genetic risk of the disease, says a study conducted by the University of Cambridge.

Both genetic and environmental factors, including diet and lifestyle, play an important role in the development of stroke.

An international team led by researchers at Cambridge developed a genetic risk score based on 90 gene variants known to be associated with stroke from 306,473 men and women in the UK Biobank.

UK Biobank is a database of biological information from half a million British adults.

Participants, aged between 40 and 73, had no history of stroke or heart attack.

Adherence to a healthy lifestyle was based on four factors: non-smoker, diet rich in fruit, vegetables and fish, not overweight or obese, and regular physical exercise.

Hospital and death records were then used to identify stroke events over an average follow-up of seven years.

Researchers found that an unfavourable lifestyle was associated with a 66 percent increased risk of stroke compared with a favourable lifestyle, and this increased risk was present within any genetic risk category.

Meanwhile, a high genetic risk combined with an unfavourable lifestyle profile was associated with a more than two-fold increased risk of stroke compared with a low genetic risk and a favourable lifestyle.

These findings highlight the benefit for entire populations of adhering to a healthy lifestyle, independent of genetic risk, according to the researchers.

Among the lifestyle factors, the most significant associations were seen for smoking and being overweight or obese.

“This drives home just how important a healthy lifestyle is for all of us, even those without an obvious genetic predisposition,” said Hugh Markus from Cambridge.

However, the study, which has been published in the journal The BMJ, is observational, so no firm conclusions can be drawn about cause and effect.