HEALTH NEWS

Study Title:

Lack of Sleep Raises Blood Pressure in Teens

Study Abstract

Background—We assessed whether insufficient sleep is associated with prehypertension in healthy adolescents.

Methods and Results—We undertook a cross-sectional analysis of 238 adolescents, all without sleep apnea or severe comorbidities. Participants underwent multiple-day wrist actigraphy at home to provide objective estimates of sleep patterns. In a clinical research facility, overnight polysomnography, anthropometry, and 9 blood pressure measurements over 2 days were made. Exposures were actigraphy-defined low weekday sleep efficiency, an objective measure of sleep quality (low sleep efficiency 85%), and short sleep duration (6.5 hours). The main outcome was prehypertension (90th percentile for age, sex, and height), with systolic and diastolic blood pressures as continuous measures as secondary outcomes. Prehypertension, low sleep efficiency, and short sleep duration occurred in 14%, 26%, and 11% of the sample, respectively. In unadjusted analyses, the odds of prehypertension increased 4.5-fold (95% CI, 2.1 to 9.7) in adolescents with low sleep efficiency and 2.8-fold (95% CI, 1.1 to 7.3) in those with short sleep. In analyses adjusted for sex, body mass index percentile, and socioeconomic status, the odds of prehypertension increased 3.5-fold (95% CI, 1.5. 8.0) for low sleep efficiency and 2.5-fold (95% CI, 0.9 to 6.9) for short sleep. Adjusted analyses showed that adolescents with low sleep efficiency had on average a 4.0±1.2-mm Hg higher systolic blood pressure than other children (P<0.01).

Conclusions—Poor sleep quality is associated with prehypertension in healthy adolescents. Associations are not explained by socioeconomic status, obesity, sleep apnea, or known comorbidities, suggesting that inadequate sleep quality is associated with elevated blood pressure.

From press release:

Teenagers are notorious for having bad sleep habits. New research suggests that having trouble staying awake the next day might not be the only consequence 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 (ages 13 to 16 years old) 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. In addition, those with poor sleep, or low sleep efficiency – having 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. Untreated high blood pressure can increase the risk for stroke and other cardiovascular diseases later in life.

The findings are from a cross-sectional analysis of 238 adolescents ages 13 to 16 years old (average age of 14) enrolled in the Cleveland Children's Sleep and Health Study. Sleep efficiency and duration was evaluated at home for three to seven nights, where teens completed a daily sleep log and wore a wrist device that measures movement to determine sleep and wake cycles. Participants also spent one night in a clinical sleep lab, where, in addition to assessing sleep with standard devices, staff measured blood pressure nine times throughout their visit.

Participants did not have sleep-disordered breathing or other known health conditions. Results were adjusted for gender, body mass index (an indicator of overweight or obesity), and socioeconomic status.

In general, adolescents need at least 9 hours of sleep a night to function at their best. However, many teens (as well as adults) 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 biological drive to sleep peaks later in the night during adolescence compared to other age groups. Combined with the daily need for 9 hours of sleep, teens face unique challenges for getting sufficient sleep while meeting typical daytime schedules.

In addition, many factors that contribute to poor sleep -- for example, stress, caffeine, nicotine, noise, bright lights, or an uncomfortable (eg, too warm) room temperature -- can be prevented. TVs and computers in the bedroom can greatly interfere with sleep – and are especially common among teens.

Signs 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.

Keeping a daily sleep log, or diary, can help you track your sleep habits and identify what might be interfering with sleep.

Study Information

Sogol Javaheri, Amy Storfer-Isser, Carol L. Rosen, and Susan Redline.
Sleep Quality and Elevated Blood Pressure in Adolescents.
Circulation.
2008 August
Case School of Medicine and Center for Clinical Investigation, Case Western Reserve University School of Medicine.