According to new research, napping frequently is linked to increased risks for high blood pressure and stroke.
The findings of the study were published in Hypertension, a journal of the American Heart Association. Researchers in China examined whether frequent naps could be a potential causal risk factor for high blood pressure and/or stroke. This is the first study to use both observational analysis of participants over a long period of time and Mendelian randomization — a genetic risk validation to investigate whether frequent napping was associated with high blood pressure and ischemic stroke.
“These results are especially interesting since millions of people might enjoy a regular or even daily nap,” says E Wang, PhD, M.D., a professor and chair of the Department of Anesthesiology at Xiangya Hospital Central South University, and the study’s corresponding author.
Researchers used information from UK Biobank, a large biomedical database and research resource containing anonymized genetic, lifestyle and health information from half a million UK participants. UK Biobank recruited more than 500,000 participants between the ages of 40 and 69 who lived in the United Kingdom between 2006 and 2010.
They regularly provided blood, urine and saliva samples, as well as detailed information about their lifestyle. The daytime napping frequency survey occurred 4 times from 2006 — 2019 in a small proportion of UK Biobank participants.
Wang’s group excluded records of people who had already had a stroke or had high blood pressure before the start of the study. This left about 360,000 participants to analyze the association between napping and first-time reports of stroke or high blood pressure, with an average follow-up of about 11 years. Participants were divided into groups based on self-reported napping frequency: “never/rarely,” “sometimes,” or “usually.”
The study found:
* A higher percentage of usual-nappers were men, had lower education and income levels, and reported cigarette smoking, daily drinking, insomnia, snoring and being an evening person compared to never- or sometimes-nappers;
“This may be because, although taking a nap itself is not harmful, many people who take naps may do so because of poor sleep at night. Poor sleep at night is associated with poorer health, and naps are not enough to make up for that,” said Michael A. Grandner, PhD, MTR, a sleep expert and co-author of the American Heart Association’s new Life’s Essential 8 cardiovascular health score, which added sleep duration in June 2022 as the 8th metric for measuring optimal heart and brain health.
