The Restless Brain

Respiratory therapy may play a key role in the battle against Alzheimer’s disease.

• By Linda Kossoff
• Nov 01, 2009

Alzheimer’s disease (AD) is a progressive and fatal brain disease that destroys brain cells, increasingly impeding the ability of sufferers to think, remember and behave normally. It is the most common form of dementia, and the seventh-leading cause of death in the United States, affecting approximately 5.3 million Americans. Most of those people are over the age of 65; however, about a half-million Americans in their 30s, 40s and 50s have the disease or some other form of dementia.

The exact cause of Alzheimer’s is not known, though the medical and scientific communities have identified specific physiological evidence in autopsies performed on those who had the disease.Within the brain of an Alzheimer’s patient, experts have noted, there is an abnormally high buildup of plaque between nerve cells, as well as twisted fibers of protein, called tangles, within dying cells.

For years, the medical community has acknowledged that sleep disturbances are characteristic of people with Alzheimer’s, especially in the later stages of the disease. Does this mean that sleep therapists can play a specific role in caring for people with AD? To answer that question, let’s look at some sleep scenarios in AD patients, as well as the latest research into how they are being addressed.

Sleeping with AD

No one becomes more familiar, more quickly, with the sleeping habits of an AD patient than their families and/or caregivers. That’s because people with Alzheimer’s tend to wake up more often and stay awake longer during the night. During these periods, they are often restless and disruptive, wandering around, or calling or yelling out. In the daytime, they may be very drowsy and tend to nap, only to become agitated by the late afternoon or early evening (this is called “sundowning”), and then unable to sleep again come bedtime.

A number of the physiological/psychological effects that commonly occur with Alzheimer’s disease tend to exacerbate these patients’ general sleeping problems. Among these are depression, restless legs syndrome, and sleep apnea.

So far, medical professionals have prescribed both drug and non-drug approaches to treat sleep changes associated with Alzheimer’s disease. However, according to the Alzheimer’s Association (AA), “Most experts and the National Institutes of Health (NIH) strongly encourage use of non-drug measures rather than medication.” It appears that the sleep medications that are commonly used in the non-Alzheimer’s population are not effective in improving sleep quality for AD patients. Furthermore, notes the Association, such medications may even increase health and safety risks for these individuals.

Might all of this mean that non-drug treatment for disordered sleeping can play a significant role in the care of today’s Alzheimer’s patients? Consider the numbers. According to a study published in the November 2008 edition of the Journal of the American Geriatrics Society, as much as 70 to 80 percent of Alzheimer’s patients experience at least five apneas every hour during sleep. Given the proven effectiveness of CPAP in the treatment of obstructive sleep apnea (OSA), it stands to reason that such treatment could yield favorable results in this arena.

CPAP and Alzheimer’s

A well-known study led by Sonia Ancoli-Israel, Ph.D., a professor of psychiatry from the Department of Psychiatry at the University of California, San Diego School of Medicine looked at 52 men and women with mild to moderate Alzheimer’s disease and OSA. Not only did researchers see significant reduction in daytime sleepiness in the randomly chosen AD patients who received six weeks of CPAP treatment, but these patients demonstrated a significant increase in cognitive function as well. Dr. Ancoli-Israel came to the following conclusion:

“This study, which showed significant improvement in patients’ neurological test scores after treatment with CPAP, suggests that clinicians who treat patients with Alzheimer’s disease and sleep apnea should consider implementing CPAP treatment.”

Nothing in Dr. Ancoli-Israel’s study indicates that OSA is a causal factor in the occurrence of Alzheimer’s,
though others in the medical community say that a body of evidence points in that direction (see Causal Theory, below). However, she did note what many respiratory therapists and providers already surmised—that OSA, gone untreated, may result in impaired cognitive function, and that CPAP treatments improve the ability of OSA patients to think, remember and function optimally. Indeed, another study of people with sleep apnea done at the David Geffen School of Medicine at the University of California, Los Angeles shows scientific evidence of tissue loss in brain regions responsible for storing memory.

A research abstract presented at the 21st Annual Meeting of the Associated Professional Sleep Societies (APSS) detailed the positive effects of CPAP on AD
patients. Presenters explained how the treatment reduced the amount of time spent awake during the night, increased the time spent in deeper levels of sleep, and improved oxygenation.

“In general, improved sleep is associated with improvements in quality of life,” concludes Dr. Jana R. Cooke, M.D. and lead researcher in another UCSD study. “Clinicians should consider CPAP treatment for Alzheimer’s disease patients with a sleep-related breathing disorder, as the potential benefits may be
significant.”

Providers and caregivers should be aware that CPAP compliance can be an especially daunting challenge when it comes to Alzheimer’s patients. If a patient isn’t 100 percent committed to the therapy, then everyone else involved must be, say experts. Caregivers of AD patients must be fully trained with the equipment and prepared to explain it more than once to the patient.

Caregivers with mild to moderate Alzheimer’s patients are more likely to have success with compliance than those caring for patients with advanced AD. However, in most cases, the brain damage in advanced patients is so great that CPAP therapy would likely have little effect.

Causal Theory

There are a growing number of medical specialists and researchers who believe that the prevalence of OSA in Alzheimer’s patients is more than an overlap of conditions. Although there are no conclusive studies that prove or disprove this, proponents of a causal theory point to compelling evidence of an undeniable connection.

One such proponent is Dr. Mack Jones, a clinical neurologist in Fort Walton Beach, Florida, and author of the book Deadly Sleep (Bartlett & Jones, 2009). Dr. Jones points out, for instance, how OSA is a recognized risk for Type 2 diabetes, and how a 2008 study published in The Archives of Neurology shows how those with Type 2 diabetes have an increased risk of developing Mild Cognitive Impairment (MCI). “More than half of people with MCI progress to AD at a rate of 12 percent a year,” Jones says. The same exact principle holds true for OSA and high blood pressure, he adds. Jones also notes findings from the use of a new brain imaging technique that reveals significant nerve fiber injury in the brains of people with OSA who had not at that time been diagnosed with AD.

Dr. Steven Y. Park, a New York City otolaryngologist, clinical assistant professor at New York Medical College and author of the book Sleep, Interrupted (PMA, 2008) also believes that OSA is a likely causal factor in the eventual development of AD.

“There are tomes of studies that link sleep apnea (and even snoring alone) with a much higher incidence of stroke (as well as heart disease),” notes Dr. Park in one of his articles. “One recent study looked at MRIs of people with sleep apnea and found a significant increase in the number of small silent strokes (or lacunar infarcts). Another study showed that people with sleep apnea had significantly reduced blood flow rates to certain critical areas of the brain. Other studies have shown that the acoustic trauma from snoring can worsen carotid artery plaque formation.

“This is just a small sampling of studies that all suggest that the process of Alzheimer’s begins long before you develop symptoms,” Dr. Park continues. “Add to this the fact that Alzheimer’s patients also have a higher incidence of depression and heart disease. And lastly, there’s a general consensus amongst Alzheimer’s researchers that this condition is a small vessel disease. Autopsy studies have revealed neurofibrilary tangles (NFTs) and senile plaques (SPs) in Alzheimer’s patients, but no one has figured out why or how these events occur. NFTs and SPs are also seen in other non-Alzheimer’s conditions as well.”

If the theory of a causal connection proves correct, then not only does the need to treat OSA become that much more imperative, but addressing the ailment early becomes a key factor in preventing progressive damage. However, it should be noted that since no definitive proof yet exists that Alzheimer’s disease is indeed caused by sleep apnea, and that CPAP therapy is a treatment for, or preventive measure against, Alzheimer’s disease, therapists and providers must take care not to make such claims. Rather, it is important to keep tabs on the progress being made by researchers in the areas of sleep and Alzheimer’s, with the hope that a breakthrough will enable respiratory providers to play a role in defeating this devastating disease.

This article originally appeared in the Respiratory & Sleep Management November 2009 issue of HME Business.