Lack of sleep associated with increased heart disease risk in elderly hypertensive patients

Getting less than 7.5 hours of sleep daily is a predictor of incident cardiovascular disease in elderly patients with hypertension, reports Kazuo Eguchi, MD, Jichi Medical University, Tochigi, Japan. “Reflecting changing lifestyles, people are sleeping less in modern societies,” he says.

Dr. Eguchi monitored the sleep patterns of 1,255 patients with hypertension, mean age 70.4 years, who were using ambulatory blood pressure monitoring. They followed the patients for a mean of 50 months to detect short sleep duration of less than 7.5 hours as well as a pattern of nighttime blood pressure rise, defined as a nighttime systolic pressure greater than that observed in the patient during waking hours. The primary end point was a cardiovascular event (stroke, fatal or nonfatal MI, sudden cardiac death.)

Results show that less than 7.5 hours is associated with a nominally significant, increased incident cardiovascular disease (CVD) (HR 1.68; p=0.03). Dr. Eguchi also reported a synergistic interaction between short sleep duration and a pattern of rising nighttime blood pressure that did not reach significance. However, patients with both shorter sleep times and nocturnal blood pressure elevations had a significantly higher incidence of CVD than those with normal or longer sleep duration and normal nocturnal blood pressure (HR 4.43; P<0.001).

“To our knowledge, this is the first report showing the prognostic importance of shorter sleep duration in combination with the nocturnal (blood pressure) dipping pattern as a risk for incident CVD,” Dr. Eguchi concludes.