Sunday, February 15, 2015

Sleep Paralysis Linked to Stress and Genetics

"Sleep Paralysis" is a disorder in which people may feel like they can't move their body when they're falling asleep or waking up, and often report hallucinations of "a malevolent presence" pressing down on them. A new study suggests the phenomenon may have a genetic cause.

In the study prepared by the University of Sheffield in England and published online Feb. 9 in the Journal of Sleep Research, researchers asked a group of more than 800 twins and siblings whether they had experienced sleep paralysis. The results showed that genetics were partially to blame for the strange phenomenon. In addition, the people in the study who had anxiety, slept poorly or had experienced stress in their lives were more likely to have these nighttime bouts of paralysis, the researchers found. The findings shed some light on what is still quite a mysterious condition.

 Sleep paralysis often occurs during the rapid eye movement (REM) stage of sleep, when people are usually dreaming. In REM sleep the muscles are nearly paralyzed, possibly to prevent people from acting out their dreams. Some people who suffer from sleep paralysis experience hallucinations of a "terrifying figure" pressing down on them and preventing them from moving. Estimates of how many people experience the phenomenon vary widely; some studies report that app. 7 percent of people will experience the feeling at some point in their lives, while other studies suggest that it affects as many as 60 percent. Yet scientists don't really know what causes the phenomenon.

Researchers used data from 862 twins (identical and nonidentical) and other (non-twin) siblings between ages 22 and 32 in England and Wales. The participants indicated on the survey whether they agreed with the statement, "Sometimes, when falling asleep or waking up from sleep, I experience a brief period during which I feel I am unable to move, even though I think I am awake and conscious of my surroundings."

By comparing the responses of identical twins who share almost all of their DNA with those of nonidentical siblings who only share about half of their DNA, the researchers found that genes accounted for more than 50 percent of the incidence of sleep paralysis. They also found that sleep paralysis was more common in people with anxiety, those who weren't getting good sleep and those who had had traumatic experiences, such as an illness or death in the family.

The researchers then studied the participant's PER2 genes, which are linked to the circadian rhythms. They found that the people who had certain versions of this gene were more likely to have sleep paralysis, intimating that something to do with the control of circadian rhythms is probably involved in sleep paralysis.

The study has a number of limitations; it was based on a relatively small number of participants, and was limited to young adults. In addition, the findings don't prove that genetics or stressful factors cause the paralyzing experience, only that the two are linked; Researches still aren't sure whether anxiety could cause a person to experience sleep paralysis, or if experiencing sleep paralysis can make a person more anxious. However their conclusions indicate that sleep paralysis appears to be heritable, and there seem to be some genes influencing sleep and wake patterns involved.


Sunday, January 25, 2015

Sleeping in a prone position may boost seizures, death in epilepsy patients.

A recent study by the University of Chicago reviewing over 250 cases of sudden unexplained death in epilepsy (SUDEP) has shown that sleeping on chest doubles the risk of sudden death in epilepsy patients. The rates are higher especially in people younger than 40.
Among 253 instances of SUDEP in which body position was documented, nearly three-quarters of the victims -- 73.3% (95% CI 65.7%-80.9%) -- were found in a prone position. In addition, the prone position was reported in all 11 cases of video-EEG-monitored SUDEP.

The apparent risk associated with prone sleeping had been noted previously in smaller case studies, but not in one this large.
Epileptic disruption in autonomic nerve function is the presumed foundation of SUDEP, but whether that manifests primarily as cardiac arrest or respiratory failure is still debated. Researchers have drawn parallels with sudden infant death syndrome (SIDS), including the possibility that they are related conditions: SUDEP occurs disproportionately in patients during sleep, and victims are often found in a prone position, the same as in SIDS. But just as SIDS can still strike infants sleeping on their backs in line with current recommendations, SUDEP can occur in any epilepsy patient at any time: an indication that the etiology of SUDEP is complex and perhaps different from one patient to the next.

While this event is rare, people with epilepsy should not sleep in a prone position (face down). Patients should have a partner remind them at bedtime or use special devices to prevent an episode.
The study published in 21st Jan edition of Journal Neurology.

Saturday, January 17, 2015

Sleep Problems in Teens Linked to Alcohol Problems

According to a recent study published in the journal Alcoholism: Clinical & Experimental Research, Teenagers ages 14 through 16 who had trouble falling or staying asleep were 47 percent more likely to binge drink than their well-rested peers. The findings are based on data collected from 6,500 adolescents who were part of the larger National Longitudinal Study of Adolescent Health, which began tracking a group of adolescents in the mid-90s.

In the study, each extra hour of sleep the teens got corresponded with a 10 percent decrease in binge drinking.Teens who had trouble sleeping when the researchers first checked in with them were 14 percent more likely to drive drunk and 11 percent more likely to have interpersonal issues related to alcohol a year later. And five years after that -when everyone was college-aged or older- those who had sleep issues in high school were 10 percent more likely to drive drunk.

Researchers have long known that lack of sleep and alcohol use are related, but the new study shows that sleep issues can actually precede and even predict alcohol use later on. Another study published in the same journal issue also found that a combination of genetics and peer influence affect teens' decisions to drink, but while a child's genetic makeup isn't something anyone can change, sleep may be something that teenagers and their parents can control.

The body's natural circadian rhythms tend to shift during adolescence, and teens may find it difficult fall asleep until 11 p.m. or midnight. Many parents and pediatricians have been pushing to delay school start times for middle and high school students.
Last year the American Academy of Pediatrics issued a policy statement calling on middle and high school to start at 8:30 a.m. or later.

The people involved in the recent study were teenagers in the 1990s, and researchers say they wouldn't be surprised if the situation has become worse due to electronic distractions such as tablets and telephones in the bedroom.