Daytime drowsiness may warn of impending death in elderly people, particularly from cardiovascular causes, new research suggests.
The findings arise from the Three City Study, a population-based prospective study conducted in France. It is the largest study done thus far to investigate the prospective association between excessive daytime sleepiness (EDS) and mortality among community-dwelling elderly.
The 8,269 subjects were age 65 years or older, and 60.3% were women. Anyone diagnosed with dementia at baseline was excluded. At the start of the study, 18.7% of participants reported “regular” or “frequent” episodes of EDS. The rest functioned as a control group.
After six years of follow-up, a total of 762 participants (8.8%) had died of any cause, including 196 who died of cardiovascular disease (CVD) and 260 who succumbed to cancer (Stroke. 2009; 40:1219-1224).
When other risk factors, such as age, gender, BMI, diabetes, and a history of CVD, were taken into account, people who reported EDS had a 33% higher relative risk of dying from any cause within six years, compared with the more alert controls. They also had a 49% higher relative risk of death from cerebrovascular disease, MI, or heart failure. No association was found with cancer mortality.
Researchers could not determine whether sleep complaints are a symptom of underlying CVD or whether they trigger or exacerbate disease. Either way, they conclude that “these data contribute to the body of evidence that EDS is not benign but rather an important risk marker,” adding that routine geriatric exams should include questions about sleep patterns.