The Impact of Sleep Disturbances on Diabetes:

BY Daniel Einhorn, MD, FACP, FACE

Introduction

Sleeping disorders affect everyone from teenagers to the elderly. Not getting a good night’s sleep can have a major negative impact on your health and well-being.

Multiple studies show that being deprived of sleep for any reason has negative effects on blood pressure, blood sugar, and fats in the blood. This in turn can lead to poorer diabetes control and complications. We have long known about the need for good nutrition and physical activity to help with diabetes. Good sleep is also important for your health and well-being.

Lack of sleep is common in adults with type 2 diabetes. This is partly because more of this group has obesity, and partly because of other factors, not fully understood, about diabetes. So, it is important that every person with diabetes and their families have an understanding of sleep issues and whether it affects them. This article will briefly review the various causes of sleep deprivation, show how it affects diabetes, and suggest how some sleep problems can be managed.

Consequences of Lack of Sleep

Daytime drowsiness is the most obvious result of poor sleep. This is not only unpleasant, but it has also been shown to increase one’s risk of accidents and to affect judgment and performance. The majority of fatal car accidents that are not caused by alcohol intake are believed to be caused by people either falling asleep at the wheel or being too tired to handle a situation. Medical interns and residents are no longer allowed to work as many hours per week as in the past because it was shown that they begin to make mistakes when fatigued, mistakes that can have grave consequences. Airline pilots have long known this.

Research shows that we eat differently when we are sleep deprived. In carefully conducted experiments, healthy volunteers were deprived of half their usual sleep time for several days. They began to eat more calories overall and to chose more calorie-dense food (junk food). It is difficult to exercise as hard or as long when we are tired. Lack of sleep makes it difficult to make the best choices in lifestyle for control of diabetes.

Sleep deprivation affects the major risk factors for heart disease. These risk factors include elevating blood pressure, raising triglycerides (fats), lowering HDL cholesterol (the good cholesterol), raising adrenaline and vascular inflammation, and directly raising glucose (blood sugar). Successfully treating sleep problems improves all these risk factors. Recent published research shows improvement in cardiovascular outcomes in sleep apnea patients who were successfully treated compared with those who were not.

Types of Sleep Problems

As with food or exercise, we are able to tolerate short-term deviations from healthy behavior without great consequence. It’s when the deviations become chronic that more serious issues begin to develop. Perhaps the most common cause of sleep deprivation in the United States is self-inflicted. We simply don’t give ourselves enough time to sleep or we allow too many distractions during sleep, such as pets or children sleeping with us, TV and radio being left on overnight, and so on. Many of us stay up late at night for work or entertainment, and then force ourselves awake with an alarm clock and coffee. As a population we sleep, on average, about 90 minutes less than our grandparents.

People who travel across time zones have long known about the impact of jet lag. A similar fact occurs in people who work alternate day and night shifts. The quality of sleep varies with stress, alcohol intake before bed, coffee intake, many medications, and even temperature of the room and number of bed covers.

Insomnia and fitful (fragmented) sleep is a common complaint. The many ads for sleep aids are evidence for how disturbing a problem this can be. Heavy meals and heavy exercise before bedtime can disrupt sleep. Many women report worsening of sleep when they are entering menopause.

Restless leg syndrome (RLS) is increasingly being recognized as a medical cause of sleep disturbance and medication can be quite successful in relieving it. The most studied form of sleep disturbance is sleep apnea.

Sleep Apnea

Sleep apnea is a condition in which a person stops breathing many times during sleep and wakes up needing oxygen. Since the person wakes for a very short time, people with sleep apnea usually do not know they have lost sleep, only that they wake up tired and stay tired all day. Very loud snoring is one sign that sleep apnea is present.

The most common type of sleep apnea is obstructive sleep apnea (OSA) caused by physical blockage of the airway during sleep. OSA is more common in obese people, in men, and in the elderly. In our study of the prevalence of OSA in adults with type 2 diabetes, we found that while less than 20% of women below age 65 had OSA, over 60% of men above age 65 had OSA.

There are studies showing that treatment of OSA in those with diabetes can lower fasting and post-meal blood sugar and A1C as much or more than any oral medication.

How to Find Out if You Have Sleep Problems

When I ask my patients about sleep, I begin with “Do you wake up refreshed?” That, more than the absolute hours they sleep, clues me in to whether a sleep problem may be present. Insomnia or fitful sleep is usually obvious, but people may not want to mention it because they think nothing can be done. The bed partner is usually needed to report on abnormal breathing or movement during sleep.

Loud snoring is a common symptom of sleep apnea. The bed partner (if not forced away by the snoring) typically observes periods of not breathing followed by loud grunts and gasps for breath. This usually goes on all night. The person usually has daytime drowsiness and falls asleep whenever it is quiet. When a patient falls asleep in the waiting room, that’s a clue! That this may go on for years is also a clue to how forgiving, or how denying, bed partners can be.

When sleep apnea or RLS is suspected, the usual course is to refer their patient to a sleep specialist. Doctors of many different backgrounds have begun to specialize in sleep problems, and there is increasing acceptance of the need for consultation. The specialist may choose to do an overnight study in a sleep lab, a facility that looks more like a hotel than a lab. Depending on what is suspected, the study may include measurements of oxygen in the blood, brain waves, movement, and other tests.

Treatment of Sleep Disturbances

Perhaps the toughest disturbance to treat is voluntary sleep deprivation. People just don’t change their sleep habits easily, much as with dieting or exercise. I encourage people to at least try a brief period of increasing their sleep time by going to bed at least one hour earlier for a week. When they do it, the results are sometimes dramatic and avoid the hassle and expense of multiple tests looking for a cause of fatigue.

Controversy continues over the use of sleep aid pills, but most clinicians are comfortable with them. The more recent sleep aids do not appear to have a large risk of dependency or addiction.

Fatigue from jet lag or changing work shift times is difficult to treat and so there are many proposed remedies. Most agree that avoiding caffeine and alcohol helps. So does shifting to the new time zone on arrival. A recent review published in the New England Journal of Medicine encourages light exposure (for waking up in a new time zone) and melatonin (for encouraging sleep in a new time zone).

RLS can usually be successfully treated with medications.

OSA is currently best treated by continuous positive airway pressure (CPAP). CPAP involves a mask worn over the nose that blows air with a high enough pressure to keep the airway open. It is not always easy to get the right level of comfort and effectiveness, and some people cannot tolerate it. But when CPAP is successful it can dramatically improve a person’s quality of life. Certain people with OSA may need surgery to widen the airway or may even need a device that repositions the jaw.

Conclusion

Sleep disturbances are very common in people with diabetes, and they are usually readily diagnosed and successfully treated. This is a matter of both quality of life and of basic health issues that are so critical to a health circulatory system. Blood sugar, blood pressure, lipids, and virtually all factors associated with diabetes are affected by sleep disturbances.

Dr. Daniel Einhorn is President Elect of the American Association of Clinical Endocrinologists, President of Diabetes and Endocrine Associates, a Clinical Professor of Medicine at the University of California San Diego, and Medical Director of the Scripps Whittier Diabetes Institute, in La Jolla, California. He was the 2005 recipient of the Yank D. Coble, Jr., MD, Distinguished Service Award from the American College of Endocrinology and Guest Editor of the Endocrinology and Metabolism Clinics of North America for Type 2 Diabetes.