Dr. Frisca Yan-Go is Medical Director of the Sleep Disorders Center, UCLA Medical Center. She and Dr. Susan Perlman, UCLA Post-Polio Clinic, work together as part of a team approach to developing treatment plans for patients with PPS at the University of California, Los Angeles (UCLA) Medical Center. Dr. Yan-Go also serves at UCLA as Associate Clinical Professor of Neurology; Co-Physician of the Headache Clinic; and Co-Physician of the Autonomic Disorders Clinic.

This report is based upon Dr. Yan-Go's presentation to the Post-Polio Support Group of Orange County, CA in May 1998. It includes information on normal sleep patterns, breathing problems, sleep apnea, plus tips for a better night's sleep. The research report, "The Value of Sleep Studies in Post-Polio Patients", concludes that polio survivors who are experiencing sleep or respiratory problems should have a sleep study.

---

If breathing problems are not recognized, diagnosed, and treated, the PPS patient may be susceptible to cardiopulmonary morbidity and mortality.

Sleep Rhythms

Our bodies have a rhythmic biological cycle called circadian rhythm that controls many bodily functions including blood pressure, temperature and sleep/wake patterns. Sleep is important for our well-being. Nighttime affects daytime; daytime affects nighttime.

Within a 24 hour cycle there are a main sleep rhythm plus a "siesta" time rhythm which is not as strong. Dr. Yan-Go tells patients that when it is time for a break at work, don't get coffee, take a snooze instead. She says it is ok to sleep on the job -- but on your own time, not on company time.

What is normal?

Normal sleep is as many hours as a person needs to be bright and alert the following day. For many, this is 7 - 8 hours; for some it may be less than 5 hours. The quantity of sleep is important to the brain. Dr. Yan-Go suggests thinking of the brain as a "sleep bank". It is a forgiving bank, but a person must pay back his debts to this "sleep bank".

Sleep Cycles

Normal sleep can be divided into two parts:

• NREM (non-rapid eye movement)
• REM (rapid eye movement)

These two types of sleep occur in a normal adult within a 90 - 120 minute cycle. Usually there are about 4 of these cycles during a night. NREM sleep is thought of as an idling brain in a moveable body. REM sleep is thought of as a highly active brain in a "paralyzed" body (except for eye and breathing muscles). REM sleep is important for thinking, memory, and mood. As a person ages, the quantity of REM sleep decreases from about 25% to 20% of total sleep. When comparing time asleep to time in bed (for sleep efficiency) the average is 85%.

Breathing Problems

Any breathing problems during daytime get worse at night. Why? Because during nighttime we have two barometers:

1. Mental abilities -- these turn inward and we raise our threshold to receive and respond to stimuli.

2. Muscle power -- during sleep muscle tone goes away. During REM sleep a person is paralyzed except for some eye and breathing muscles. Thus when an individual is in a horizontal position as for sleep, gravity pulls everything downward and crowds a person's breathing.

If a polio survivor is having breathing problems during the daytime, these problems will increase at night. Why? Because the brain must choose between breathing rhythm and sleeping rhythm. Naturally, it selects breathing because this function is essential to life. The breathing process exchanges chemicals so that the body can survive. Sleeping is just a necessary function. Whatever interrupts breathing interrupts sleep; when sleep is interrupted a person is more fatigued during the daytime.

Some people with PPS may be experiencing the following symptoms, which may indicate sleep disturbance:

• headache
• increased fatigue
• insomnia
• difficulty maintaining nocturnal sleep
• daytime sleepiness

These symptoms may be caused by:

• pulmonary dysfunction with chronic alveolar underventilation [retention of carbon dioxide in blood whereby blood oxygen levels decrease]

• sleep disordered breathing including obstructive sleep apnea.

If these causes are not recognized, diagnosed, and treated the PPS patient may be susceptible to cardiopulmonary morbidity and mortality.

What is Sleep Apnea?

Sleep apnea is defined as the cessation of breathing for ten or more seconds during sleep. There are a number of predisposing factors:

• occurs predominantly between ages 40 - 70 years
• ten times more frequent in men
• anatomic abnormalities such as upper airway and cranio-facial abnormalities
• obesity
• pharmacologic (use of alcohol, and other drugs)
• hypothyroidism

There are two types of sleep apnea: obstructive and central.

1. Symptoms of Obstructive Sleep Apnea include:

• excessive daytime sleepiness
• very loud snoring
• awakenings/gasping or choking
• awakenings for uncertain reasons
• restless sleep
• poor memory (intellectual function)
• irritability/personality change
• morning headache

2. Central Sleep Apnea occurs when the brain fails to send the message to breathe. [Oxygen therapy is usually not recommended for polio survivors. It can cause a decreased respiratory drive so that the brain turns off the need for ventilation.]

Sleep Apnea Treatment Options

Decisions regarding treatment are based upon severity of symptoms and signs, sleep study results, and treatment/risk benefit ratio.

1. Behavioral treatment options:

• avoid central nervous system depressants. Do not use alcohol as sleep medication.
• avoid upper airway irritants (cigarettes)
• body positions (elevate head of bed with blocks, bed pillow, or adjustable bed)
• weight loss -- Dr. Yan-Go acknowledges this is difficult for PPS patients. Other options should precede this. However, she does urge patients to avoid continuing to gain weight.

2. Mechanical treatment options:

• CPAP (nasal continuous positive airway pressure)
• BiPAP (bi-level positive airway pressure)
• dental appliances that move jaw slightly forward
• nasopharyngeal intubation
• nasal splints on CPAP or BiPAP can prevent airway collapse

3. Pharmacologic treatment options:

• Protriptyline (stimulates breathing)
• nasal decongestants
• others (asthma medications)
• oxygen [rarely used for PPS, only used for lung disease]

4. Surgical treatment options:
Caution: these may result in rebound insomnia

• tracheostomy
• tonsillectomy/adenoidectomy
• nasal surgery
• plastic surgery of throat
• maxillofacial surgery

Research:

1. Yan-Go, F., Perlman, S., and Williams, A.: The Value of Sleep Studies in Post Polio Patients. Amer. Sleep Disorder Ass. 7th Annual Meeting. (pp 22-27) (1993).

   Sleep studies were conducted on ten UCLA PPS patients with sleep complaints (three male, seven female). Only one of these people had normal sleep with a 93% sleep efficiency (determined by time in bed divided by sleeptime). Average sleep efficiency is 85%.

   Of the nine patients with abnormal sleep studies, four had moderately abnormal sleep efficiency ranging between 39% - 78% but a normal respiratory disturbance index and no significant sleep apnea. Two of these four showed a higher than normal number of arousals for no apparent reason, and one showed periodic leg movement disturbances of 33 per hour. None of these four patients required assisted ventilation.

   The remaining five patients had sleep efficiency ranging from 5% to 65%. All of them had presumptive alveolar hypoventilation [defined under Breathing Problems], three of them requiring ventilatory assistance. All had serious sleep disordered breathing, with respiratory disturbance indexes between 0 and 82 and significant worsening of their chronic alveolar hypoventilation. In addition, one patient suffered prolonged oxygen desaturation (less than 60%) lasting up to 15 minutes in both NREM and REM sleep. Two patients with tracheostomies required nocturnal mechanical ventilation assistance. Another patient required a tank respirator during sleep and developed severe obstructive sleep apnea.

   Dr. Yan-Go, et al, concluded that sleep studies should be performed on PPS patients with sleep or respiratory complaints. PPS patients with or without alveolar hypoventilation may have sleep apnea while patients with hypoventilation may be further compromised during sleep. These patients require nocturnal mechanical ventilation, preferably using a positive pressure device to avoid the development of sleep apnea.

2. Hsu, A.A., Staats, B.A.,: "Postpolio" sequelae and Sleep-Related Disordered Breathing. Mayo Clin Proc. 1998 Mar;73(3):216-24. PMID: 9511778; UI: 98172769 {Abstract}

   This study published in Mayo Clinic Proceedings, March 1998 reported similar results. It identified three patterns of sleep disturbance -- obstructive sleep apnea, hypoventilation, and a combination of both. It concluded that sleep related disordered breathing is a late sequela of poliomyelitis and clinical evaluation should include information about sleep.

Conclusion

Sleepiness has become a public health issue. SLEEPINESS CAN KILL. It is the third most common cause of disability and death for young adults in motor vehicle accidents. Dr. Yan-Go suggests this option: take a catnap before you drive.

If you are having sleep or breathing problems, seek help. Ask your sleep partner if he/she is aware of any problems you may have. Sleep studies should be performed on PPS patients with sleep or respiratory complaints in order to recognize, diagnose, treat problems, and help prevent further complications.

For more information:

Frisca Yan-Go, M.D.
Suite B 200
300 UCLA Medical Plaza
Los Angeles, CA 90024-6975
310-794-1195