Healthy Sleep Pattern Can Offset Genetic Stroke Risk

Lu Qi, MD, PhD

New data from Tulane University has found healthy sleep patterns can offset the risk of stroke and heart disease, regardless of a person’s genetic risk profile.

An analysis of more than 350,000 Europeans found improved sleep patterns could have prevented more than 10% of incidents of cardiovascular disease and stroke observed during the study.

"We wanted to test whether the relation between sleep scores and cardiovascular outcomes was different according to the genetic risk. This is the first time this has been done,” said lead investigator Lu Qi, MD, PhD, Director of Tulane University Obesity Research Center at Tulane University. "We also wanted to estimate the proportion of cardiovascular problems that would not have occurred if all participants had a healthy sleep pattern, if we assume there is a causal relationship."

In hopes of furthering the understanding of sleep and its impact on heart or blood vessel problems, investigators designed a prospective study examining genetic risk scores, sleep patterns, and risk of stroke and cardiovascular events using data from UK Biobank patients. From the database, investigators identified 385,292 patients with a median follow-up of 8.5 years for inclusion.

For the purpose of the study, investigators excluded Biobank participants with known cardiovascular disease and those with missing values on the main exposures. Investigators noted only participants of European descent were included in the analysis of genetic risk factors and sleep scores. Genetic risk scores, which were calculated using single nucleotide polymorphisms from blood samples of UK Biobank patients, were classified as high, intermediate, or low risk.

Assessments of sleep behaviors were conducted through self-reporting by participants and based on five sleep factors. Sleep scores ranged from 0 to 5, with 5 being the highest, and the low-risk patients had an early chronotype, sleep 7 to 8 hours per day, never or rarely experience insomnia, did not snore, and no frequent excessive daytime sleepiness. Of the 385,292 included, 21.8%, 37.0%, and 27.9% had sleep scores of 5, 4, and 3, respectively—patients with higher sleep scores were more likely to have lower BMI and lower prevalence of preexisting hypertension and diabetes.

During the study period, a total of 7280 instances of cardiovascular events were recorded. Of these, 4667 were coronary heart disease cases and 2650 were stroke cases.

In adjusted models, short (less than 7) and long (more than 9) sleep duration, insomnia, snoring, and excessive daytime sleepiness were all associated with increased risk of cardiovascular disease and coronary heart disease. In fully-adjusted models accounting for factors including BMI, hypertension, and diabetes status, all of these associations remained significant except for snoring.

When examining impact of sleep scores, investigators observed patients with a score of 5 had a 35% (19—48%), 34% (22–44%), and 34% (25–42%) lower risk of cardiovascular disease, coronary heart disease, and stroke, respectively, compared to patients with a score of 0 to 1. Investigators noted results suggest more than 10% of incident cardiovascular disease, coronary heart disease, and stroke events could be prevented if all participants were in the low-risk group for all 5 sleep factors.

"As with other findings from observational studies, our results indicate an association not a causal relation,” Qi added. “However, these findings may motivate other investigations and, at least, suggest that it is essential to consider overall sleep behaviors when considering a person's risk of heart disease or stroke."

This study, titled “Sleep patterns, genetic susceptibility, and incident cardiovascular disease: a prospective study of 385 292 UK biobank participants,” was published online in the European Heart Journal.