London, Mar 16 (IANS): People who sleep less than five hours a night could be at 74 per cent risk of developing peripheral artery disease (PAD) compared with seven to eight hours, according to a new study.

More than 200 million people globally have peripheral artery disease (PAD), where arteries in the legs are clogged, 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," study author Shuai Yuan of the Karolinska Institute, Sweden said.

"Lifestyle changes that help people get more sleep, such as being physically active, may lower the risk of developing PAD. For patients with PAD, optimising pain management could also enable them to have a good night's sleep," Yuan said.

The study, published in European Heart Journal-Open, included more than 650,000 participants to analyse the associations of sleep duration and daytime napping with the risk of PAD; and to examine causality of the associations.

In an observational analysis of 53,416 adults, sleeping less than five hours a night was associated with a nearly doubled risk of PAD compared with seven to eight hours.

This finding was supported by further analyses in 156,582 and 452,028 individuals. In the causal studies, short sleep was associated with an increased risk of PAD. In addition, PAD was associated with an increased likelihood of short sleep.

"The results indicate that brief night-time sleep can raise the chance of developing PAD, and that having PAD increases the risk of getting insufficient sleep," Yuan said

Regarding long sleep, in an observational analysis of 53,416 adults, sleeping eight hours or more per night was linked with a 24 per cent higher risk of PAD compared with seven to eight hours. This finding was supported by analyses in two larger populations of 156,582 and 452,028 individuals.

However, no causal relationships were found between long sleep and PAD.

Similar results were reported for napping, where daytime nappers had a 32 per cent higher risk of PAD compared to those who did not nap but no causal links were found.

"More studies are needed on the relationships between lengthy night-time sleep, daytime napping and PAD," said Yuan. "Although we found associations in the observational studies, we could not confirm causality."