Wednesday, January 29, 2014

Melatonin and Prostate Cancer

Melatonin is the hormone produced by your brain when it gets dark - it tells your brain it's time to sleep. This study analyzed levels of a melatonin metabolite in the urine of older men from Iceland. The results showed that melatonin metabolite levels were lowest in those that reported sleep aid use, trouble falling asleep, or trouble staying asleep. And those men that had the highest levels of the metabolite had a 75% decreased risk of advanced prostate cancer.

The article does not discuss possible mechanisms, and more studies are needed before melatonin is recommended to ward off prostate cancer.

Wednesday, January 22, 2014

Using your smartphone to evaluate snoring and obstructive sleep apnea

In sleep medicine, there is a push to move the diagnosis of sleep apnea from the sleep lab to the patient's home. Home sleep studies are done routinely in certain regions of the US - the northeast and west coast, specifically.

Smartphones can do many things these days. These researchers from Japan developed an app for an Android phone that can monitor snoring and even obstructive sleep apnea. The app did this by measuring sound from the patient. Snoring was measured in a similar way that it is done in a sleep lab. But sleep apnea was measured in a novel way - by counting the number of "dips" in sound during recording. The app was tested alongside a standard in-lab sleep study and found to be relatively accurate.

The authors point out that the study has limitations...the first being that the subjects who tested the app were suspected of having sleep apnea. So more research is needed to see if this app would work in the general population as a screening tool. Also, how would the smartphone react if the patient and their bedpartner were snoring? Perhaps the bedpartner could sleep in a separate room for a night to allow the app to evaluate only the patient. The last limitation was that the correlation between sleep apnea severity detected by the app and the in-lab sleep study was not as good when the patient has mild to moderate sleep apnea. It was more accurate for severe sleep apnea.

The authors propose that an app like this could be used less for diagnosis, and more for monitoring changes in snoring as patients change their sleeping position or lose weight. In a commentary after the original article, it was suggested that the app could be used in combination with the phone's accelerometer to alert a patient that they are on their back and snoring. The patient would then roll on their sides again. I can envision an app like this combined with a wire that measures oxygen levels and pulse rate to make a diagnosis at home. This could be an even cheaper home study than what is available now.

Wednesday, January 15, 2014

CPAP and Parkinson's Disease

Patient's with Parkinson's Disease often have difficulty staying asleep. They are also sleepy. This can be due to the disease or some of the Parkinson's medications. Obstructive sleep apnea (OSA) is also common in Parkinson's Disease. This may be due, in part, to loss of neuromuscular control of the upper airway muscles - allowing the throat to collapse easier.

This study looked at patients with Parkinson's Disease that had OSA. They gave the patients CPAP and placebo CPAP, monitored nightly use, and measured sleepiness objectively. The results showed that CPAP deepened sleep and reduced daytime sleepiness. Patients were able to use the CPAP consistently despite having the motor control problems common in Parkinson's Disease. Interestingly, CPAP use did not reduce the amount of time spent awake after initially falling asleep. The authors point out that this points to the inherent sleep difficulties of Parkinson's patients, even after their OSA is treated.

Wednesday, January 8, 2014

Sleep and Our Health

Here is an interesting summary article about the importance of sleep and our health. The author discusses how sleep affects memory, the endocrine system, the immune system, and psychiatric disorders. The author uses quotes from a Harvard sleep researcher, Dr. Stickgold, who explains some of the recent findings about sleep and health.

I thought his description of dream importance was a little confusing. In the beginning, he suggests dreams are "much, much less important" than once thought. Then he describes how dreams help us remember and organize recent events. Perhaps he means dreams are less important with regard to analysis of the unconscious?

Thursday, January 2, 2014

Sleep and technology

This article discusses the findings from the National Sleep Foundation's Sleep in America Poll from 2011. Some of the questions involved sleep quality and use of technology in the hour leading up to trying to sleep. The results showed that using stimulating technology that was interactive, like video games, cell phones, and computers was more disruptive to sleep than passive technology like watching TV or listening to music. The authors speculate that using stimulating technology may prevent the natural withdrawal of the sympathetic nervous system activity that is needed for sleep onset.

The implications of this research are intriguing. The results challenge, at least in part, that using passive technology in the bed can disrupt sleep. What seems to be most disruptive to sleep is stimulating technology. These findings could be extrapolated to other stimulating activities performed in the hour before bedtime, whether technology is involved or not. So perhaps the rule that the bed should be used for sleep only needs to be modified - it's possible that passive activity is not necessarily going to disrupt sleep. This goes along with my clinical experience in treating patients with chronic insomnia. Some of them have been going to sleep with the TV on in their bedroom since middle or high school. Yet their insomnia does not start for several years later, often in their late 20's. In these individuals, watching TV in the bedroom may not negatively impacting sleep quality as once thought.