Sleep is such a crucial aspect of health that it can have an adverse impact on some very serious diseases such as:

• Parkinson disease (PD)
• Alzheimer disease (AD)
• Multiple sclerosis (MS)
• Gastrointestinal tract disorders
• Kidney disease
• Behavioral problems in children

This is all according to a report in a recent issue of the Journal of the American Medical Association (JAMA). The report is based on studies presented at annual joint meeting of the American Academy of Sleep Medicine and Sleep Research Society.

"Many medical illnesses disrupt sleep and impair alertness. Moreover, sleep disorders may coexist with medical disorders in people of all ages. Improving sleep problems in the medically ill, sleep specialists say, may enhance patients' overall health and quality of life," says Lynne Lamberg of JAMA.

Sleep and Problems in Children

A study has found that children with attention deficit-hyperactivity disorder (ADHD) have more sleep apnea than do other children. Researchers conducted a retrospective review of 86 children aged 5 years or older evaluated for snoring in a pediatric sleep laboratory. Of the 40 found to have sleep apnea, five were diagnosed with ADHD. Of the remaining 46 children with primary snoring but no OSA, only one had been diagnosed with ADHD.

Whether OSA contributes to or worsens ADHD or whether children with ADHD are at increased risk for OSA is not clear, the researchers said, but they suggest screening children with ADHD for trouble breathing, bed-wetting, restless sleep, and other sleep apnea symptoms.

In another study of children, researchers found that 31% of 114 children evaluated for sleep apnea in their laboratory were overweight. Researchers recommend intensive weight intervention for at-risk children.

Light Therapy, Sleep, and Alzheimer Disease

According to the JAMA report, "A simple nondrug therapy exposure to bright light reduced nighttime agitated behavior and improved continuity of nighttime sleep in institutionalized people with AD."

Researchers from the Goldman Institute on Aging of the University of California, San Francisco, randomly assigned 26 subjects (avg. age 86 years), to spend 1 hour outdoors in the morning or to receive usual indoor light exposure for 10 weeks.

Participants in the study wore actigraphs, wristwatch-style movement-activated recording devices, at periodic intervals to provide objective indicators of the change in their activity and sleep.

Parkinson Disease (PD)

According to the JAMA report:

German researchers found that people with PD and impaired cognitive performance had sleep of worse quality, with more trouble falling asleep, staying asleep, and moving at night, than healthy controls did. They were also more likely to have depression. As their depression deepened, their memory deteriorated further. Improving sleep and depression may improve cognitive performance in these patients, suggest Bertram Holinka, MD, and colleagues at the University-Hospital Knappschaftskrankenhaus in Bochum. 

In another study, French researchers note that People with PD who are receiving dopaminergic drugs often report visual hallucinations while awake and unusually vivid dreams during sleep. They confirmed the abnormal sleep patterns by observing 10 PD patients taking levdopa. (LOOK UP) They found that all the patients had abnormal motor behaviors during rapid eye movement (REM) sleep, a state in which skeletal muscles ordinarily lie virtually paralyzed.

Multiple Sclerosis (MS)

A new wakefulness-promoting drug, modafinil (Provigil), lessens the common and disabling symptom of fatigue in people with MS, researchers found.

Researchers performed a multicenter, single-blind, placebo-controlled trial, using 72 adults with stable MS and fatigue. The study lasted 9-weeks, with patients taking a placebo in weeks 1 and 2, 200 mg/d of modafinil in weeks 3 and 4, 400 mg/d of modafinil in weeks 5 and 6, and a placebo in weeks 7, 8, and 9.

The lower dosage of the drug significantly reduced daytime sleepiness and fatigue without disturbing nighttime sleep.

Patients generally tolerated the drug well, the researchers found, with nervousness and headache being the most common adverse effects.

Modafinil was approved by the US Food and Drug Administration in 1998 to combat sleepiness in people with narcolepsy.

In another study, researchers found that modafinil reduced excessive daytime sleepiness in the majority of nearly 500 people with narcolepsy at dosages of 200 mg, 300 mg, or 400 mg per day for 40 weeks, with continuing efficacy, few adverse effects, and no evidence of tolerance.

Cancer

Several reports examined sleep disruption in people with cancer. Barry Fortner, PhD, of Rush-Presbyterian-St Luke's Medical Center, and colleagues, using a standard self-report assessment of sleep, found that 44% of 128 adult outpatients with cancer slept poorly. The higher the sleep disturbance, the lower the patients' overall quality of life.

Epilepsy and Sleep Apnea

According to the JAMA report:

The frequency of patients having both epilepsy and obstructive sleep apnea (OSA), a sleep-related breathing disorder, is greater than would be expected by chance, according to Peter Höllinger, MD, and colleagues at the University Hospital, Bern, Switzerland.

Of 615 patients with OSA seen in their sleep center in the last 6 years, 21 also had epilepsy ... Successful treatment with continuous positive airway pressure often improved seizure control and reduced excessive daytime sleepiness in at least one third of these patients.

Nocturia (Nighttime Urination)

Research at the University of Alabama at Birmingham schools of nursing and medicine suggests that sleep apnea can increases nighttime voiding.

Another study found a 60% rate of undiagnosed sleep apnea as well as strong associations between sleep apnea symptoms and nighttime urination. In addition, many of the subjects also appeared to be relatively dehydrated on arising. The dehydration, the researchers caution, may trigger acute orthostatic hypotension on getting out of bed and potential toxicity from taking water-soluble drugs, such as digoxin, early in the day. They found that treatment of the sleep apnea eliminated the nocturia and other sleep apnea symptoms.

To view the abstracts presented at the sleep meetings, go to http://www.apss.org.

Journal of the American Medical Association, November 1, 2000; 284 and annual joint meeting of the American Academy of Sleep Medicine and Sleep Research Society