Teens need eight to 10 hours of sleep a night, according to guidelines from the American Academy of Sleep Medicine.

Unfortunately, on most weeknights the average high schooler only gets about six-and-a-half hours of sleep.

In adults poor or disturbed sleep is associated with high blood pressure. It can also raise blood pressure in teens, according to a presentation by team of researchers at the recent American Heart Association's Epidemiology, Prevention, Lifestyle and Cardiometabolic Scientific Sessions.

Teens who slept less than eight hours were five times more likely to have hypertension than so-called “good sleepers.”

“It is safe to say sleep health matters for heart health, and we should not wait until adulthood to address it,” Julio Fernandez-Mendoza, senior author on the study and a professor and director of behavioral sleep medicine at Penn State University School of Medicine, said in a statement.

When teens complain they don't get enough sleep, parents, teachers and policy-makers need to listen, Axel Robinson, first author on the study, urges. Robinson is a 17-year-old senior at Pelham Memorial High School in New York, where a four-year scientific research program is offered.

About 420 teens from three school districts in the Harrisburg, Pennsylvania area participated in the study over three years. Their average age was 16.5 years old.

The teens filled out questionnaires and participated in a sleep study conducted in a lab. Their seated blood pressure was taken at same time as the sleep study.

Thirty-five percent of participants reported they had symptoms of insomnia — trouble falling or staying asleep — and 50 percent said they slept less than eight hours in the lab. The researchers noted the likelihood that some teens may not have slept as well there as they would have at home.

A combination of insomnia and an inadequate amount of sleep can contribute to more serious health outcomes than a lack of sleep alone, the researchers said. Teens who reported insomnia symptoms and slept less than eight hours were five times more likely to have clinical hypertension than so-called “good sleepers” who had no symptoms and slept eight hours or more.

Teens who slept less than eight hours, but did not have trouble falling asleep, were three times more likely to have elevated blood pressure: an average systolic blood pressure measurement of 120 mm Hg or higher and an average diastolic measurement of 80 mm Hg or lower than good sleepers.

“It is safe to say sleep health matters for heart health, and we should not wait until adulthood to address it.”

Teens who had trouble falling asleep, but who slept more than eight hours, did not seem to be at risk for elevated blood pressure or stage 2 hypertension (an average systolic blood pressure measurement of 140 mm Hg or higher and/or an average diastolic measurement of 90 mm Hg or higher).

Good sleep hygiene is the best way for teens to improve their sleep, Brooke Aggarwal, an assistant professor at Columbia University Medical Center in New York, explained. She suggests teens create a relaxing bedtime routine for themselves. This should involve limiting their screen time before they go to bed, avoiding heavy meals and caffeine late at night, and getting regular exercise during the day.

“Setting healthy sleep patterns during the teen years could carry over into adulthood,” Aggarwal, who was not involved in the study, added.

The study has not yet been published in a peer-reviewed journal, so its findings are considered preliminary.