Trouble falling asleep may signal high blood pressure

Trouble sleeping, especially trouble falling asleep, may be associated with high blood pressure, according to a new study from China.

This is the first study to show that certain people with insomnia are at risk for high blood pressure, said co-authors Dr. Xiangdong Tang of Sichuan University in China and Dr. Alexandros N. Vgontzas of Penn State University College of Medicine, in a statement to Reuters Health.

Insomnia with increased alertness during the day, or hyperarousal, is associated with increased chronic secretion of stress hormones like cortisol, which may lead to hypertension, they wrote.

The authors studied about 300 adults, including more than 200 chronic insomniacs who’d had trouble sleeping for at least six months. They all spent one night in the Sleep Medicine Center of West China Hospital and took a sleepiness/alertness test the following day.

At night, they were allowed to sleep as they normally would, in sound, light and temperature-controlled rooms. The next day, they were given four 20-minute nap opportunities throughout the day. Researchers measured their “sleep latency,” that is, the amount of time it took for the nappers to actually fall asleep, if they were able.

Researchers also took their blood pressure readings in the evening and in the morning.

Normal sleepers were no more likely to have high blood pressure even if they took longer to fall asleep for a nap.

For chronic insomniacs, the longer it took to fall asleep when they tried to nap during the day, the more likely they were to have high blood pressure, even after accounting for age, gender, weight and height, diabetes, and use of alcohol, tobacco and caffeine.

Compared to normal sleepers who fell asleep quickly, people with insomnia who took more than 14 minutes to fall asleep during the day were three times as likely to have high blood pressure readings or a doctor’s diagnosis of hypertension, the authors report in the journal Hypertension.

People who fell asleep in less than 14 minutes, regardless of whether or not they had insomnia, had no increased risk of high blood pressure.

About half of insomniacs and a third of the normal sleepers took more than 14 minutes to fall asleep during the day, Tang and Vgontzas wrote in the statement.

People who have trouble sleeping should ask their doctors about their blood pressure readings, they wrote.

“Insomniacs who have either short sleep at night or show signs of hyperalertness during the day are at risk for hypertension,” they wrote. “This is similar to someone who has other risk factors such as obesity, high lipids, smoking, etc.”

The United States Preventive Services Task Force recommends screening for high blood pressure for all adults over the age of 18 every year or so, regardless of sleep patterns, USPSTF chair Dr. Michael LeFevre noted in an email to Reuters Health.

Blood pressure screening causes few major harms, LeFevre said.

“However, many people who have high blood pressure in (a doctor’s) office setting do not have sustained high blood pressure outside of a medical setting,” he said. “Making the diagnosis of hypertension based only on office readings may lead to unnecessary treatment.”

Blood pressure measurements should be repeated outside the doctor’s office during the course of the day to confirm high blood pressure before diagnosing hypertension, he said.

Most people will need help from a doctor or sleep expert to start falling asleep more quickly, Tang and Vgontzas wrote.

source: interaksyon.com

Bedroom computers, TV may add to autism sleep issues

NEW YORK -- Kids with autism and related disorders are prone to sleep disturbances but a new study finds that screen time, especially in the bedroom, may make their sleep problems worse.

When researchers compared boys with autism spectrum disorders to other boys, they found that all the kids with bedroom access to media slept fewer hours, but the relationship was twice as strong for the boys with autism.

"In-room media access was associated with about 1.5 fewer hours of sleep per night in the group with autism," said Christopher R. Engelhardt, who led the study at the University of Missouri-Columbia.

"This association can potentially be problematic, particularly if the reduction in sleep interferes with other daily activities, such as school, homework, interactions with other people, or driving," he told Reuters Health in an email.

Past studies suggest that up to 80 percent of kids with autism, and related conditions like Asperger syndrome, experience sleep troubles, including difficulty falling asleep or staying asleep through the night. Children with attention deficit hyperactivity disorder also are known to have a high rate of sleep disturbances.

With both conditions, it's unclear why sleep is so difficult. Theories include a disruption in sleep-wake cycles that are regulated by the hormone melatonin, which is often deficient in kids with ASDs, Engelhardt and his colleagues write in Pediatrics.

Because kids with autism spectrum disorders, like those with ADHD, also tend to spend a lot of time watching TV and playing video or computer games, the researchers wondered whether that could be contributing to their sleep problems.

So they recruited the parents of 49 boys with autism spectrum disorders, 38 with ADHD and 41 comparison boys with typical development to fill out questionnaires about their children's bedroom screen access and sleep patterns. All the kids were between ages eight and 17.

Boys with autism who had TV, computers or video games in their bedrooms got less sleep than all the other boys, including boys with autism who didn't have media in their bedrooms.

Without a TV in their room, boys with autism spent an average of about nine hours sleeping, compared to less than eight hours among kids with an ASD and a bedroom TV.

In contrast, bedroom TVs didn't seem to make a difference for boys with ADHD or typical development.

Boys with autism with computers in their rooms slept nearly two hours less than boys with autism and no bedroom computer.

A lot of time spent playing video games, regardless of where they were located, was also linked to shorter sleep times among boys with ASDs.

Even for typical children, too much time with TV or video games has been linked to attention problems, hyperactivity, arguments and physical fights, Engelhardt said.

"We can't say that access to a TV causes less sleep," only that the two are linked for some kids, he said.

Last month, the American Academy of Pediatrics called for limiting screen time for all kids to one or two hours per day.

"This is a good recommendation for all children," Dr. Beth Marlow, Burry Chair in Cognitive Childhood Development and director of the Sleep Disorders Division at Vanderbilt University Medical Center in Nashville, Tennessee.

"Following this recommendation for kids with (autism spectrum) and ADHD is good, although children with (autism spectrum) or ADHD who are still having difficulty with sleep despite limiting electronics really deserve a sleep evaluation by their pediatrician or sleep specialist."

Sleep troubles can also stem from anxiety, sleep apnea, pain that the child might not be able to express, gastrointestinal problems or seizures, she said.

For typically developing kids, bedroom TV access doesn't usually seem to cut into sleep.

"However, (Engelhardt's) finding for teens with ASD concurs with our clinical impressions -- that these teens have difficulty 'switching off' videogames," Michael Gradisar said.

Gradisar is a clinical psychologist who studies technology use and sleep, especially among teens, at Flinders University in Adelaide, South Australia.

"Many teens have a distorted sense of time passing when playing videogames, however, it may be that this time distortion is stronger for teens with ASD," he said.

Parents can have a tough time managing how much their children play games or watch TV, he said. "It may take quite some time to do, but one option is for parents to introduce other hobbies and activities into their teens lives, so that videogaming eventually occupies less time."

People with autism tend to spend more time with media outlets, researchers think, because the electronic worlds have engaging audio and visual features and their social interactions are easy relative to real life interactions.

This doesn't necessarily mean that parents should take TVs or video games out of their autistic children's rooms, but might consider limiting or monitoring media consumption, he said.

"Screen media can certainly be good for kids with autism," he said. "Scientists have long known that video games are great at teaching and reinforcing certain behaviors, so it's possible that these games can be used to adjust and shape the types of behaviors generally valued by society, such as behaviors intended to help others."

source: interaksyon.com