Healthy Elderly With Daytime Sleepiness Face Higher Risk Of Cardiovascular Death
Healthy elderly people who regularly feel very sleepy during the day had a significantly higher risk of dying from cardiovascular disease, a study reported in Stroke: Journal of the American Heart Association.
Elderly people who reported regularly feeling sleepy during the day had a 33 percent increase in relative risk of overall death compared to those who didn’t feel sleepy. Even after researchers adjusted for such other risk factors as age, gender, body mass index and previous cardiovascular disease, the sleepy people also had a 49 percent increase in relative risk of cardiovascular death.
Researchers conducted the Three-City Study for six years in France, following 9,294 elderly people without evidence of existing cancer or cardiovascular disease and who did not live in nursing homes or other care facilities.
“Complaints of excessive daytime sleepiness are very frequent in the elderly but there have been few studies relating daytime sleepiness and mortality in the elderly and those results were mixed,” said Jean-Philippe Empana, M.D., Ph.D., lead author of the study and a researcher at Inserm, the French Public Institute on Health and Medical Research.
In Empana’s study, the average age of participants was 74 years old and 60 percent were women.
At the onset of the study, participants completed a short questionnaire (derived from the Epworth sleepiness scale, a validated questionnaire to assess daytime sleepiness) to report whether they felt sleepy during the day: 14 percent said “regularly” and 4.7 percent “frequently.”
After following the participants for six years, 762 had died. Of the deaths, 34 percent were because of cancer and 26 percent were from cardiovascular disease.
Although the results point to an association between excessive daytime sleepiness and an increased risk of cardiovascular death, Empana said, “we are far from having a clear explanation.”
Two-thirds of the participants had an ultrasound exam of their carotid artery, and investigators found no association that an increase in carotid plaque would explain.
“Also, we thought there might be an underlying sleep apnea syndrome, so we looked at snoring and obesity, but once we adjusted for that, we still have a significant association between excessive daytime sleepiness and cardiovascular disease death,” Empana said.
Researchers are unclear on whether the sleep complaints are a symptom of an underlying disease or whether the sleepiness triggers or worsens a disease.
Physicians should ask patients about their sleep habits and closely monitor elderly patients for signs of excessive daytime sleepiness, Empana said.
“These data may have clinical implications adding to the body of evidence that excessive daytime sleepiness is not a benign but rather an important risk marker of death in community-dwelling elderly,” he said. “The main aim is to be aware of sleep complaints and to look for them routinely in the elderly, because it may be associated with the worse prognosis.”
The Three-City Study is conducted under a partnership agreement between the Institut National de la Sante et de la Recherche Medicale (INSERM), the Victor Segalen–Bordeaux II University, and Sanofi-Aventis. The Fondation pour la Recherche Medicale funded the preparation and initiation of the study. The 3C Study is also supported by the Caisse Nationale Maladie des Travailleurs Salaries, Direction Generale de la Sante, MGEN, Institut de la Longevite, Conseils Regionaux of Aquitaine and Bourgogne, Fondation de France, and Ministry of Research–INSERM Programme “Cohortes et collections de donnees biologiques.”