STOCKHOLM, Sweden — Getting too little sleep at night could nearly double the risk of clogged leg arteries, a new study reveals. Scientists at the Karolinska Institute say sleeping less than five hours is linked to a 74 percent jump in risk of developing peripheral artery disease (PAD), compared with seven to eight hours.
More than 200 million people globally have peripheral artery disease (PAD), data shows. The disease causes the arteries in the legs to clog, restricting blood flow and increasing the risk of stroke and heart attack.
“Our study suggests that sleeping for seven to eight hours a night is a good habit for lowering the risk of PAD,” says study author Dr. Shuai Yuan, in a statement. “Insufficient night-time sleep and daytime napping have previously been associated with a raised risk of coronary artery disease which, like PAD, is caused by clogged arteries.
“In addition, sleeping problems are among the top ranked complaints in PAD patients,” adds Yuan. “There are limited data on the impact of sleep habits on PAD and vice versa, and our study aimed to fill that gap.”
The team studied 650,000 participants in a two-part analysis. Researchers first carried out an observational study, which explored the link between sleep duration and daytime napping with the risk of peripheral artery disease. They then used genetic data of 608,610 adults to do naturally randomized controlled trials called Mendelian randomization.
“Observational analyses are limited by reverse causality – meaning that if an association between sleep habits and PAD is found, we cannot be certain if sleep habits caused PAD or having PAD caused the sleep habits,” explains Yuan. “Mendelian randomization is a robust method for evaluating causality and provides more certainty about the results.”
The observational analysis of just under 53,500 adults shows that those who slept less than five hours a night were nearly double at risk of PAD.
The Mendelian randomization method supported this finding. Results show that while short sleep increased the risk of peripheral artery disease, the condition was linked to an increased likelihood of short sleep.
Does excess sleep impact PAD risk?
Sleeping too much can also be risky. The adults who slept for eight hours or more were linked to a 24 percent higher risk of developing peripheral artery disease. However, the Mendelian randomization method shows that there was no causal relationship found between long sleep and PAD.
This was similar to the results of those who took naps. Daytime nappers had a 32 percent higher risk of PAD but there were no causal links found.
“More studies are needed on the relationships between lengthy night-time sleep, daytime napping and PAD,” says Yuan. “Although we found associations in the observational studies, we could not confirm causality. More research is needed on how to interrupt the bidirectional link between short sleep and PAD.
Lifestyle changes that help people get more sleep, such as being physically active, may lower the risk of developing PAD,” Yuan adds. “For patients with PAD, optimising pain management could enable them to have a good night’s sleep.”
The study is published in the European Heart Journal.
Report by South West News Service writer Alice Clifford.