August 18, 2008

By Megan Rauscher

NEW YORK (Reuters Health) – Teenagers who don’t sleep well or long enough may be at increased risk for developing high blood pressure (also called hypertension), which could herald heart disease later on, according to a study published today.

“These findings add to growing research indicating the many negative consequences of inadequate sleep, which other studies have shown include increased risk for obesity, poor daytime function, and in adults, heart disease and death,” Dr. Susan Redline, who led the study, told Reuters Health. Redline is director of University Hospitals Sleep Center at Case Western Reserve University in Cleveland, Ohio.

In the study of 238 boys and girls, aged 13 to 16 years, those getting less than 6.5 hours of sleep per night were 2.5-times more likely than those getting more nightly shut-eye to have hypertension or “pre-hypertension,” (blood pressure bordering on high), with blood pressure readings in the 90th percentile for their height, age, and gender.

Moreover, teens found to be poor sleepers — whose time in bed consists of more than 15 percent time awake (due to awakening during the night) — were 3.5 times more likely to have elevated blood pressure than teens spending more time asleep.

Adolescents in the study who had trouble falling asleep at night or who woke up too early had an average 4 millimeters of mercury (4mL Hg) higher systolic blood pressure (the top number in the blood pressure reading) compared to children who were better sleepers, Redline and colleagues found.

They report their findings in Circulation: Journal of the American Heart Association.

A total of 14 percent of the adolescents studied had elevated blood pressure, 26 percent were poor sleepers and 11 percent slept for less than 6.5 hours per night, instead of the recommended 9 hours of sleep per night.

Nearly two thirds of the adolescents not getting enough sleep also had trouble falling asleep and staying asleep, while 28 percent of teens who had trouble falling asleep and staying asleep also had short sleep duration. Adolescents with known sleep disorders or other illnesses were excluded from the study.

These findings, Redline told Reuters Health, “further emphasize a need for individuals of all ages — children and adults — to recognize the fundamental role of sleep in maintaining health and to adopt habits conducive to consistent and sufficient sleep.”

In an AHA-issued statement, Redline noted part of the problem is the “technological invasion” of the teen bedroom with computers, cell phones and music. “There are teens who text messages or listen to music all night,” and the problem compounded by early school hours, making early rising necessary.

“Parents should optimize sleep quality for their family with regular sleep and wake times and bedrooms should be kept quiet, dark and conducive to sleep,” she said.

SOURCE: Circulation, August 18, 2008.