A study published in European Heart Journal has found that good sleep patterns can offset genetic risk for cardiovascular diseases (CVDs).
The study looked at genetic variations (single-nucleotide polymorphisms [SNPs]) that are already known to be linked to heart disease and stroke among 385,292 healthy participants in the UK Biobank project and used the data to create a genetic risk score.
A sleep score ranged from 0 to 5, with 5 being the healthiest sleep pattern, representing a "morning" person, who slept 7-8 hours a night, without insomnia, snoring or daytime sleepiness.
Participants were followed up for an average of 8.5 years, during which time there were 7280 cases of heart disease or stroke.
The researchers found that compared with those with a sleep score of 0 to 1 (unhealthy sleep pattern), participants with a score of 5 had a 35 per cent reduced risk for CVD and a 34 per cent reduced risk for both heart disease and stroke.
Participants with both a high genetic risk and a poor sleep pattern had a more than 2.5-fold greater risk for heart disease and a 1.5-fold greater risk for stroke compared with those with low genetic risk and a healthy sleep pattern. This translated to 11 more cases of heart disease and five more cases of stroke per 1000 people a year among poor sleepers with a high genetic risk compared with good sleepers with low genetic risk. A healthy sleep pattern compensated slightly for a high genetic risk, with just over a two-fold increased risk for these people.
The authors say, if the associations are causal, more than 10 per cent of CVD, coronary heart disease and stroke events could have been prevented if all participants had been in the low-risk group for all five sleep factors.