Researchers in China found frequent napping may be a signal of higher risks of blood pressure and stroke. The findings suggest that individuals who sometimes or frequently napped had an increased risk of hypertension and stroke compared to individuals who never nap. While napping itself isn’t the issue, researchers say it could be a sign of potential underlying health issues.
According to a new study by researchers in China, frequent naps could be a risk factor for high blood pressure and stroke. The study, published in Hypertension, a journal produced by the American Heart Association, is the first to look at whether frequent napping was linked to high blood pressure and stroke by using both observational analyses of participants over a long period. Researchers combined the method with Mendelian randomizationTrusted Source, where scientists use genetic markers to examine whether a risk factor can cause a particular disease.
Earlier studies on this link have provided conflicting conclusions. For instance, this 2017 study found daytime napping may be associated with a higher risk of hypertension, while a 2019 studyTrusted Source found daytime napping may be protective against hypertension. For the observational analysis, the researchers analyzed data from the UK BiobankTrusted Source.
That study recorded genetic and health data from more than 500,000 participants ages 40-69 living in the United Kingdom between 2006-2010. Participants who already had hypertension or a stroke by the beginning of the study were excluded from the results. Ultimately, researchers looked at 358,451 participants to study the association between the frequency of naps and first-time reports of stroke or high blood pressure.
Researchers divided the participants into groups according to the frequency of nap-taking categories: usually, sometimes, and never/rarely.
Among those: 50,507 had hypertension, and 4,333 had strokes with median follow-ups of 11.16 years. With the prospective observational analysis, researchers found participants who napped in the daytime more frequently were more likely to be male, older, non-European, less educated, have a lower income, have a higher body mass index, waist-hip ratio, and Towsend deprivation index (a measure of material deprivation). These frequent nappers also reported having worse health overall, and were also more likely to sleep for a longer period and to have sleep problems like snoring.