You may want to report your afternoon napping habits to your primary care provider.

A new study published in the medical journal SLEEP compared the daytime nap habits of nearly 87,000 adults to their mortality rates. The researchers looked at nap duration, variability of nap duration and time of day. Almost 6% of the study’s total participants had died during the follow-up period of 11 years.

Analysis revealed longer naps, greater variability of nap duration, and more naps around noon and in the early afternoon were tied to greater mortality risk. These results were adjusted for participants’ health and lifestyle factors.

“Daytime sleepiness is common in aging adults as the part of the brain that controls the circadian rhythm also ages,” explains Dr. Yelena Tumashova, a sleep medicine physician at Advocate Health Care. “An aging sleep-wake cycle can look like shifting sleep schedules, waking up at night, needing more time to recover after a change in sleep or daytime napping. However, it’s still worth mentioning it to your doctor, especially since this study encourages us to consider daytime napping as a potential health risk factor.”

Possible underlying causes of daytime sleepiness include: