Teens with poor sleep habits may have higher blood pressure

Aug 18 2008

In new research, the sleeping habits of teenagers has come under scrutiny and has found that not getting enough sleep may be linked to a rise in their blood pressure.

Teenagers worldwide are renowned for their bad sleep habits but the latest research suggests that having trouble staying awake the next day might not be the only problem they face.

In the first study to look at the relationship between not getting enough sleep and blood pressure in healthy adolescents, researchers found that healthy teens, age 13 to 16 years who slept less than 6.5 hours a night were 2.5 times more likely to have elevated blood pressure compared to those who slept longer.

It was also found that those with poor sleep, or with trouble falling asleep or staying asleep had, on average, 4 mm Hg higher systolic blood pressure (the top number) and were 3.5 times more likely to have prehypertension or hypertension than their peers who slept well.

High blood pressure later in life, if left untreated, can increase the risk for stroke and other cardiovascular diseases.

The findings are the result of an analysis of 238 adolescents ages 13 to 16 years old enrolled in the Cleveland Children's Sleep and Health Study.

Their sleep efficiency and duration was evaluated at home for three to seven nights, and the teenagers completed a daily sleep log and also wore a wrist device that measures movement to determine sleep and wake cycles.

They also spent one night in a clinical sleep laboratory, where, in addition to assessing sleep with standard devices, staff measured blood pressure nine times throughout their visit.

The teenagers did not have sleep-disordered breathing or other known health conditions and the results were adjusted for gender, body mass index and socioeconomic status.

These results are similar to findings from other studies in adults and suggest that poor sleep may be associated with significant health consequences for adolescents.

But the researchers say larger studies and analyses with blood pressure measurements repeated over time are needed to confirm the findings.

Experts say most adolescents need at least 9 hours sleep a night to function at their best, however, many teens regularly sleep less.

In this study, participants slept on average 7.7 hours a night, with 11 percent sleeping 6.5 hours or less a night.

The researchers say the biological drive to sleep peaks later in the night during adolescence, compared to other age groups, and combined with the daily need for 9 hours of sleep, teens face unique challenges for getting sufficient sleep while meeting typical daytime schedules.

They say many factors contribute to poor sleep such as stress, caffeine, nicotine, noise, bright lights, or an uncomfortable (e.g., too warm) room temperature and these can be prevented.

They say TVs and computers in the bedroom can greatly interfere with sleep and are especially common among teens.

Indications of not getting enough sleep or sleeping poorly include consistently taking more than 30 minutes to fall asleep, awakening more than a few times or for long periods each night, feeling sleepy during the day, or having trouble concentrating at school or at work.

The researchers advise those with sleep problems to keep a daily sleep log, or diary, to help track sleep habits and identify what might be interfering with sleep.

The study "Sleep Quality and Elevated Blood Pressure in Adolescents" is published online in the August 19 issue of Circulation: Journal of the American Heart Association and was supported by the National Heart, Lung, and Blood Institute (NHLBI) of the National Institutes of Health.