Category Archives: Insomnia

More Evidence Insomnia Increases the Risk of Stroke

A study from Taiwan published in the April issue of the journal Stroke titled Insomnia Subtypes and the Subsequent Risks of Stroke, Report From a Nationally Representative Cohort demonstrates the relationship between insomnia and stroke. Over a four-year period, 21,438 subjects with insomnia and 64,314 matched subjects without insomnia were followed.

The results were very interesting and potentially of great importance. The authors found that the incidence of stroke was 54% more likely to occur in those with insomnia as opposed to good sleepers. However, even more astonishing, subjects age 18 to 34 with insomnia had an eight-fold greater risk of stroke. Additionally, when those with insomnia were broken down by chronicity, the rate was considerably higher in those with persistent insomnia.

The authors concluded that the evidence seems to indicate that those with insomnia have a higher risk of stroke than as compared to non-insomniacs. They urge that health education about insomnia should be promoted, especially among the young who seem to be most vulnerable to stroke as a result of poor quality sleep.

This is the first study to show a significant relationship between insomnia and stroke. Several prior studies have demonstrated that short sleep duration can predispose one to stroke. In fact, a study I mentioned in a previous blog titled Sleepless in Stroke-ville demonstrated a four-fold increase of stroke in people who slept less than six hours.

Why would insomnia and sleep deprivation increase one’s risk of stroke? I suspect, as do the authors, that it is multifactorial. They both can negatively affect cardiovascular health through inflammation and metabolic dysregulation, as evidenced by diabetes and increased release of stress hormones. In addition, the over-activity of the sympathetic nervous system results in increased blood pressure. Taken together, these factors put a great deal of stress on the vascular system and over time can destroy its integrity. Thus, we see the high incidence of stroke noted in this study and the increase in heart attacks observed in others.

The take home message is that we need to become more aware of the relationship of sleep to health. If you chronically limit yourself to less than six hours of sleep, you need to do things to increase the duration. Such things as going to bed earlier, establishing a set sleep-wake schedule, turning off the computers and cell phones, and avoiding caffeine after noon can make a big difference. If you suffer from insomnia as defined by the fact that you try to sleep longer but cannot, then talk to your health care provider. There are excellent therapies, many of them non-pharmacological such as CBT (cognitive behavioral therapy) available to deal with insomnia. Remember, in most cases a stroke causes irreversible damage, so be proactive.

What Do You Mean I Was Sleeping?

Every year I see many patients that tell me that they get only a few hours of sleep each night. In fact, I have had several swear they barely sleep at all. In most cases, they honestly believe this to be true. Interestingly, if we bring them into our sleep lab, many of these individuals will insist that they slept only a few hours when their electroencephalogram (EEG) indicates that they actually slept much longer.

This is a type of insomnia called Paradoxical Insomnia, also referred to as Sleep State Misperception. Previously, we thought it to be rare and probably present in no more than five percent of insomnia sufferers. We now know this to be incorrect. Furthermore, in several recent studies, the incidence is closer to 50% when defined as misperceiving sleep as wake time by at least one hour or more per night.

As a result, we are now coming to realize there are two basic types of insomniacs–those who sleep greater than six hours but perceive they sleep less, and those who actually sleep less than six hours and accurately estimate their sleep time.

Why is it important to differentiate the two? The group that in reality sleeps less than six hours is much more likely to develop hypertension, diabetes, and suffer earlier death than the group that misperceives their sleep time. These findings are potentially revolutionary when it comes to our understanding of the diagnosis and treatment of insomnia. Consequently, we need objective data in order to differentiate these two types since effective treatment approaches are different.

What I find fascinating is that those with misperception are more likely to respond to CBT (Cognitive Behavioral Therapy). While those who actually sleep less than six hours, the short sleeper type, are more likely to require pharmacological therapies. We believe this to be because the short sleepers have an underlying level of physiological hyperarousal. They have elevated levels of stress hormones such as cortisol and adrenaline, while the misperception group seems to demonstrate more of a psychological basis for their insomnia.

The good news is that in sleep medicine we now have accurate tools for differentiating these two types. We have a device called an actigraph that is worn like a wristwatch on the subject’s arm. It correlates movement with wakefulness and its absence with sleep. Even more astonishing is a new form of technology called the Sleep Profiler. It records the subject’s brain waves during the night at home, accurately differentiating sleep from wake and also the distinctive stages of sleep. In fact, I have used this form of technology in my own practice with great success.

Due to our new understanding of insomnia and these technological advances, we can offer our patients evidenced-based therapies. As with many other things in medicine, we are learning that in the treatment of insomnia, one size does not fit all.

Is Your Technology Keeping You Up At Night?

computerIf you own a cell phone, iPad, computer or a laptop and have a hard time falling asleep, your technology might be to blame for your tossing and turning.

Within our eyes there are cells known as rods and cones, which are necessary for normal vision. Our eyes also contain retinal ganglion cells that store melanopsin. Melanopsin is particularly sensitive to blue light, a band of light in the narrow 400-480nm range. When blue light hits the retina a signal is sent to the hypothalamus and melatonin production is turned off and delayed by several hours. This results in an inability to fall asleep and causes difficulty when waking up, as melatonin levels are inappropriately elevated in the morning.

Blue light is everywhere and can be found within the displays of iPads, computers, laptops, cell phones. New government mandated CFL (compact florescent lighting) and LED (Light emitting diode) bulbs, which give out much more blue light than the previous versions, can also create an excess of blue light. With this increase in blue light exposure it’s no wonder we are seeing an epidemic of sleep deprivation.

A lack of sleep can manifest itself in many way such as; increased stress, cognitive dysfunction, chronic diseases mood disorders and obesity. In fact, in a recent study, hamsters exposed to blue light at night developed cellular changes in an area of the brain called the hippocampus. This part of the brain is very much involved in memory and emotional processing.

So, short of going back to pre-industrial revolution conditions, what can we do to decrease our exposure to blue light and get our circadian sleep wake cycle back to normal? You can turn off your laptop, iPad, and other electronics gadgets, including that your LED TV, at least two hours before bedtime. You can also use red night lights in your bedroom for illumination; since red light has the lowest effect on melatonin production of all light wavelengths.

Another idea, which I have instituted successfully, in many of my patients is to where blue blocker sunglasses at night. These are very effective in screening out blue light. Finally, there is available a computer program that alters the color of your computer display according to the time of day it is called F.Lux and can be found online.

The bottom line is that we are being bombarded with blue light. More than 200 million computers are purchased worldwide per year. We need to be aware of what I would call blue light pollution. By taking measures to prevent over exposure at the wrong time of day we can do much to improve our health.