Weight Loss Improves Metabolic Parameters and Sleep Disordered Breathing in Children

This article describes findings from a study presented at the American Thoracic Society about how weight loss can improve metabolic markers and sleep disordered breathing in adolescents.

New Findings About Our Biological Clock

This article describes some interesting findings about how our biological clock may control how when we wake and when we sleep.

Obstructive Sleep Apnea and Diabetes

Here is an article about data presented at the American Thoracic Society linking obstructive sleep apnea (OSA) to type 2 diabetes. This study confirms what we already think clinically about OSA and diabetes.

Gabapentin for Insomnia in Women

Many women suffer with insomnia symptoms, and these can get worse as a woman approaches menopause. A case series was published in the April edition of the Journal of Clinical Sleep Medicine about using Gabapentin for this problem. The author, Dr. Guttoso, hypothesizes that in women who are approaching menopause, low estradiol levels may contribute to nighttime awakenings. Gabapentin is an anti-seizure medication, but it has been shown to improve sleep quality and can improve deep sleep amounts. It's not clear how Gabapentin would improve sleep quality in pre-menopausal women with nighttime awakenings.

He presents histories of three women, all of which had insomnia symptoms. In the first case, the woman took Gabapentin nightly. Within a few weeks, she was sleeping better, had more daytime alertness, better concentration, and improved mood. She did have dizziness, but this was not all the time and did not seem to interfere with her functioning. The second woman reported that nightly Gabapentin also relieved her insomnia symptoms, with a temporary side effect of daytime sleepiness and irritability. However, after about three weeks of therapy, those side effects disappeared. For the last woman, she again reported elimination of her insomnia symptoms with nightly Gabapentin. She denied any side effects, and stated that Gabapentin enhanced her daytime alertness, improved her concentration, and gave her more daytime energy. She was even able to stop drinking coffee at work.

Of course more research is needed to determine if women that are close to menopause have nighttime awakenings in associated with low estradiol levels, and whether Gabapentin can improve sleep quality in randomized controlled clinical trials.

A Sleep Mask to Help With Lucid Dreaming?

Just saw this about a new sleep mask that supposedly can help people with lucid dreaming. That occurs when people are conscious while dreaming. I am not sure how this mask would work, but here is the link to the article.

CPAP Use and High Blood Pressure

This article discusses how regular use of continuous positive airway pressure (CPAP) in obstructive sleep apnea may reduce high blood pressure.

Reversing Brain Abnormalities in Childhood Obstructive Sleep Apnea

Here is a news brief about childhood obstructive sleep apnea (OSA). In kids, untreated OSA can cause learning, attention, and behavioral problems. In fact, some kids with OSA are incorrectly diagnosed as attention deficit disorder. It is thought that OSA can actually damage kids' brains. A new study shows that treating OSA can reverse some of the brain damage done and improve kids' learning, attention, and behavior.

Sleep Apnea and Cancer Risk

Here is a news brief about two studies showing that obstructive sleep apnea (OSA) may increase the risk of cancer. Repetitive oxygen decreases in OSA may be the culprit. OSA is also linked with obesity, diabetes, high blood pressure, heart disease, and stroke - all of which are associated with increase risk of cancer as well.

Obstructive Sleep Apnea, Delerium, and Knee Replacement Surgery

Apparently, the incidence of post-operative delirium after knee replacement surgery is rather high - 32% according to a study. Mr. Flink and others did an experiment to see what pre-existing medical conditions are associated with post-operative delirium in knee replacement surgery patients. Their results are published in the April edition of the Anesthesiology Journal and showed that 27 of 106 (or 25.5%) patients developed post-op delirium after their knee surgery. Of note, these patients were all elderly. Among patients with obstructive sleep apnea (OSA), 53.3% had post-op delirium, compared to 20.9% of patients without OSA. After multiple statistical analyses, only OSA was consistently a significant independent predictor of post-op delirium, among the medical conditions monitored. The reason why OSA may contribute to post-op delirium is not known. The study authors mention repeated oxygen level drops as a cause, which is possible. OSA can also cause general inflammation, which apparently can increase the chance of developing post-op delirium. I wonder if delirium is more common because OSA causes sleep fragmentation, even if the oxygen levels do not decrease dangerously low. More studies are needed for sure.

Interestingly, post-op delirium still occurred in those patients who used their CPAP in the hospital, but the incidence of delirium was less than in those with OSA that did not use their CPAP in the hospital. But there were not enough patients in the sample to be statistically significant. My clinical experience is that patients do better when they bring their CPAP to the hospital for use before and after surgery. It will be interesting to see if a larger study shows an objective decrease in post-op delirium with the use of CPAP.

Room Temperature and Obstructive Sleep Apnea

Dr. Valham and others published the results of an interesting study in the April edition of the Sleep Journal. He noted that some of his patients told him they snore less when their bedroom is at a colder temperature. He then designed an experiment to test whether obstructive sleep apnea (OSA) would lessen in a colder environment as well.

He studied 40 patients by having them do 3 sleep studies, each at 61 degrees F, 69 degrees F, and 75 degrees F, but in random order. The results showed that the OSA severity was significantly higher at 61 degrees versus 75 degrees. But, the patients slept 31 minutes longer and slept significantly better in the 61 degree room. Also, those in the coldest room reported the most alertness the next morning! These results are confusing as you might think that the more severe the OSA, the lower the sleep quality and less alert someone would be the next day.

However, this just points to the fact that OSA severity does not determine completely how someone feels the next day. I have patients with very severe OSA who do not feel tired at all and tell me they sleep well each night. I also have patients who barely meet criteria for OSA who can not sleep well and have a difficult time staying awake during the daytime.

Back to this study - the researchers did not measure snoring to see if that had reduced with the cooler room temperatures. That data would be interesting to see. Also, the researchers can not explain why the OSA would be more severe as the room gets cooler. Finally, even though the subjects slept better, there was no difference in the proportion of the different sleep stages at the different room temperatures.

The implications from this study is that room temperature can help you sleep longer, sleep better, and improve your morning alertness - these results may help insomniacs improve their sleep quality.

Traumatic Memories, Emotional Reactions, and Sleep

Here is an interesting study printed in the January edition of the Journal of Neuroscience. Researchers showed study subjects neutral and traumatic pictures and assessed their ability to remember them as well as the emotional responses. For one group, they showed the pictures shortly after they woke up and the other group saw them right before going to bed. The results showed that recognition of the pictures was greater when the pictures were shown right before sleep, demonstrating that sleep (particularly dream sleep) is helpful in laying down memories. But, the emotional reactions were less if they were shown the pictures right after getting up and not allowed to sleep. The emotional reaction was the same or even intensified in those that saw the images right before bed - and this was especially true in those that had more dream sleep. This implies that depriving oneself of sleep or at least not sleeping for 12 hours after witnessing a traumatic event could reduce the negative emotional reaction to the event. This could have clinical applications in how psychiatrists treat post-traumatic stress disorder.