FEELING SLEEPY? SNORE LOUDLY?

SEE YOUR DOCTOR AS THESE COULD BE THE PRESENTING SYMPTOMS OF OBSTRUCTIVE SLEEP APNEA!

Obstructive sleep apnea (OSA) is potentially a life-threatening condition that is far more common than is generally thought. It often remains undiagnosed in many people. It is of paramount importance for the public to be aware of this common, serious, and treatable condition, so that appropriate measures can be instituted to prevent adverse consequences. This article tries to answer some commonly asked question about OSA.

WHAT IS SLEEP APNEA?
‘Apnea’ is a Greek word meaning ‘without breath’. Apnea in practice is defined in adults as cessation of breath that lasts at least ten seconds. There are two types of sleep apnea namely central and obstructive. Obstructive sleep apnea (OSA), the most common form of apnea, occurs when tissues in the upper airway collapse intermittently during sleep, thereby blocking the passage of air. Central sleep apnea is much less common. It is caused by some problem in the central nervous system, most likely a failure of the brain to signal the airway muscles to breathe.

HOW COMMON IS OSA?
It has been estimated that 4-8% of middle-aged men and 2-4% of middle-aged women have OSA with excessive sleepiness.

WHO GETS OSA?
OSA can affect both males and females of all ages, including children, and without regard to weight. However, it occurs more commonly in people who have a family history of sleep apnea, excess weight, a large neck, a recessed chin, male sex, abnormalities in the structure of upper airway, smoking and alcohol use.

WHAT CAUSES OSA?
Many conditions can cause or predispose a person to have OSA. These include small upper airway size, obesity, neck muscle hypertrophy, nasal obstruction, cranio-facial abnormalities, sleep position, tobacco, alcohol, etc. In these patients mechanical and structural problems in the airway cause the interruptions in breathing, when the throat muscles and tongue relax during sleep. This can partially or completely block the opening of the airway (See diagram below). With a narrowed or blocked airway, the person continues his or her efforts to breathe, but air cannot easily flow into or out of the nose or mouth.

…Sleep study is a test that records a variety of body functions during sleep, such as brain waves, eye movement, muscle activity, heart rate, airflow, respiratory effort, blood oxygen level, body position, and leg movements.

WHAT ARE THE CONSEQUENCES OF UNTREATED OSA?
The consequences of OSA can be divided into short-term and long-term. Short-term consequences include falling asleep inappropriately, morning headaches, irritability, memory problems, sexual dysfunction, heartburn, nocturia (a need to use the bathroom frequently at night), job impairment and increased risk of motor vehicle accidents. Untreated OSA patients are 3 times (or more) likely to have automobile accidents. Long-term consequences include increased risk of developing high blood pressure (it has been estimated that 50% of OSA patients have high blood pressure), heart attack, heart failure, cardiac rhythm abnormalities and stroke.

WHEN SHOULD OSA BE SUSPECTED?
People who have OSA often are not aware of their condition and may not believe it when told. For many, their bed partners or family members are the first ones to suspect that something is wrong, usually from their heavy snoring and apparent struggle to breathe. Friends or coworkers of the victim may notice that the individual falls asleep during the day at inappropriate times (such as while driving, working or talking).

Other symptoms that might be present are morning headache, dryness of mouth on awakening, forgetfulness, irritability, impaired mental or emotional functioning, decreased libido and impotence in men, etc.

AM I AT RISK OF HAVING OSA?
Your answers to this sleep quiz will help you decide if you might suffer from sleep apnea:

1. Are you a loud, habitual snorer?
2. Do you feel tired and groggy on awakening?
3. Are you often sleepy during waking hours and/or can you fall asleep quickly?
4. Are you overweight and/or do you have large neck?
5. Have you been observed to choke, gasp or hold your breath during sleep?

If you or someone close to you answers ‘yes’ to one or more of the above questions, you should discuss your symptoms with your doctor.

HOW IS OSA DIAGNOSED?
The diagnosis of OSA is made based on medical history, physical examination and most importantly, an overnight polysomnography (sleep study), the gold standard in diagnosing OSA. Overnight sleep study can be done at the Normah Medical Specialist Centre sleep clinic (available locally) or alternatively, we can arrange to conduct the study in the comfort of your own home (Home Sleep Study). Sleep study is a test that records a variety of body functions during sleep, such as brain waves, eye movement, muscle activity, heart rate, airflow, respiratory effort, blood oxygen level, body position, and leg movements. These tests are used both to diagnose OSA and to determine its severity. In general, if there are more than 5 episodes per hour, apnea is significant.

HOW IS OSA TREATED?
The treatment of OSA is tailored to the individual based on medical history, physical examination, and the results of sleep study. Medications are generally not effective in the treatment of sleep apnea. Some general measures like changes in sleeping habits (eg. rolling over onto the side), reducing weight, avoidance of sleeping pills, quit smoking and abstinence from alcohol within four hours of sleep may be tried for milder cases. Other treatment options are discussed below.

1. Nasal continuous positive airway pressure (CPAP)
   CPAP is the most effective and commonly used treatment for OSA. In this procedure, the patient wears a mask over the nose during sleep, and pressure from an air blower forces air through the nasal passages. The air pressure is adjusted so that it is just enough to prevent the throat from collapsing during sleep. The pressure is either constant or variable depending on the types of devices used (ie. Manual-CPAP or Auto-CPAP). Nasal CPAP prevents airway closure while in use, but apneas return when CPAP is discontinued or used improperly. It has been shown in studies that CPAP therapy reduces a patient’s risk of death, major cardiovascular or cerebrovascular events, systolic blood pressure problems, and improves left heart functions. It also improves the quality of life of patients and prevents increased risk of motor vehicle accidents.
2. Dental appliances
   Dental appliances that reposition the lower jaw and the tongue may be helpful to some patients with mild to moderate OSA.
3. Surgery
   Some patients with OSA may need surgery. A wide range of procedures have been used to increase the size of airway but unfortunately, none of them is completely successful or without risks. In general, surgery should be avoided in the obese, or if OSA are frequent or severe. The procedures that have been used are uvulopalatopharyngoplasty (UPPP), laser-assisted uvulopalatoplasty (LAUP), mandibular advancement procedure, maxillo-facial surgery, tonsillectomy and adenoidectomy, excision of obstructing mass, etc.

Conclusion
Obstructive sleep apnea is a common, serious, and treatable condition that is frequently undiagnosed due to lack of awareness of the symptoms as well as the seriousness of the problems. Serious consequences can be avoided with proper identification of the symptoms and treatment.

Sleep Study test is available in NMSC.
For queries and/or appointment,
please contact no: 082-440055 ext: 4261/645
Contributed by : Dr Soo Hua Huat, Visiting Neurologist, NMSC