| Q: |
What are the types of sleep-disordered breathing?
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| A: |
There are several types, the most common is snoring, followed by
sleep apnea caused by upper airway obstruction. Another type is central
sleep apnea, which may occur in people with severe heart failure, but
can also occur spontaneously or in association with neurological
conditions such as strokes. Obesity hypoventilation syndrome is another
type of sleep-disordered breathing in which the morbidly obese person
can have significant breathing pauses during the night, leading to
respiratory failure.
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| Q: |
What is sleep apnea?
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| A: |
Sleep apnea is a form of sleep-disordered breathing where there
are breathing pauses–air entry into the lungs is temporary
halted–despite continued effort to take a breath. Sleep apnea is said to
occur when the pauses last for 10 or more seconds and are repeated
regularly throughout the night. The common symptoms are snoring and
choking that may lead to awakening during the night. Very often, the
person with sleep apnea is unaware of the problem and of being sleepy
during the day, and it is the bed partner who brings it to medical
attention.
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| Q: |
How common is sleep apnea?
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| A: |
Sleep apnea is very common, affecting more than 4 of 100 people
in the middle-aged population, and is more common than either diabetes
or asthma. The chances of developing sleep-disordered breathing become
more common with increasing weight and age but it can affect anyone at
any age, from babies to the elderly.
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| Q: |
What are the daytime symptoms of sleep apnea?
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| A: |
Over 9 in 10 people with sleep apnea experience excessive daytime
somnolence, or abnormal sleepiness. This can lead to driving
impairment, intellectual impairment, personality changes, mood
disturbances, reduced libido/impotence, marital disharmony,
irritability, and a reduced quality of life.
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| Q: |
What are the night-time signs of possible sleep apnea?
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| A: |
These signs are usually reported to the person with sleep apnea
by a bed partner; occasionally the person is aware of the events
themselves. Snoring is the most common event and occurs in 90–95 percent
of all cases. Other signs include witnessed breathing pauses (75
percent), a dry mouth in the morning (75 percent), excessive sweating
(50 percent), choking attacks (25 percent), and urination at night (25
percent). An absence of snoring does NOT exclude sleep apnea.
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| Q: |
What causes the breathing pauses in sleep apnea?
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| A: |
In sleep, the muscle tone of the upper airway (pharynx) tends to
narrow and collapses temporarily. This results in repetitive breathing
pauses accompanied by a drop in blood oxygen levels and arousal from
sleep, and leads to daytime symptoms of sleep apnea.
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| Q: |
What are the risk factors for the development of sleep apnea?
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| A: |
Being male, middle-aged, and obese (see Calculating body mass index (BMI))
confers the greatest risk of developing sleep apnea. Other risk factors
include mild abnormalities of the jaw and facial structure, such as an
overbite or a smaller lower jaw. The structure of the face, especially
the middle, and the shape of the hard palate, nasal blockage, and
problems with breathing through the nose, as well as large tonsils,
adenoids, and a large tongue, can all lead to sleep apnea. Between 30
and 50 percent of people with sleep apnea are NOT obese.
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| Q: |
Is the type of obesity important in the development of sleep apnea?
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| A: |
Central obesity with a high waist:hip ratio is a greater risk for
the development of sleep apnea. That means that people with an
apple-shaped body (excess weight around the waist) are generally at
greater risk than people with a pear-shaped body (weight around the
hips). See Calculating body mass index (BMI) to find out how to determine if you are overweight.
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| Q: |
What makes sleep apnea worse?
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| A: |
Alcohol can worsen sleep apnea by reducing the activity of the
upper airway and dilating muscles that prevent the airway from closing
over during sleep. Sedatives have a similar effect; they also have the
potential of reducing respiratory drive. Sleep deprivation, nasal
congestion, and sleeping on your back can also worsen sleep apnea.
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| Q: |
Does sleep apnea have any other effects on health?
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| A: |
Sleep apnea may contribute directly to conditions such as high
blood pressure (hypertension) and there is a possible association with
heart attacks and strokes. Severe sleep apnea can lead to increased
breathing risks while being anesthetized for surgery. Sleep apnea can
lead to problems with concentration and memory, and is associated with
depression and mood impairment.
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| Q: |
How is sleep apnea diagnosed?
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| A: |
Sleep apnea syndrome is diagnosed on the basis of symptoms of
excessive daytime sleepiness and an overnight sleep study to objectively
document breathing pauses. This can be done using a variety of methods,
including full PSG (polysomnography) or home-based sleep studies with
more limited apparatus. It could simply involve a probe on the finger
(oximeter) to look at overnight breathing patterns and the changing
levels of oxygen in the blood (oxygen saturation patterns). An
experienced sleep technologist will score and assist in the
interpretation of the study data.
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| Q: |
How is sleep apnea treated?
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| A: |
The best treatment for moderate to severe sleep apnea is using a
machine that generates continuous positive airway pressure (see Treating sleep apnea with CPAP).
Milder forms of sleep apnea can be treated using a mouth-guard splint,
called a mandibular repositioning splint, which is constructed by a
prosthodontist, orthodontist, or dentist. The device acts by pulling the
lower jaw forward and opening the airspace at the back of the throat.
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| Q: |
Are there lifestyle measures that will help?
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| A: |
Weight loss (if you are overweight or obese) can help reduce the
severity of sleep apnea. Cut out alcohol, particularly before bedtime,
don’t take sedatives, and if you smoke, quit. Not sleeping on your back
may help if your apnea occurs only in that position, and can be achieved
with positional training.
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| Q: |
Is surgery an option for treating sleep apnea?
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| A: |
Surgery is usually not recommended for moderate to severe apnea
but there are circumstances when it may be useful. For example, if the
tonsils or adenoids are too large, they can be removed. If the soft
palate and uvula are too big they can be reduced with laser-assisted
uvulopalatoplasty (LAUP) or supported with a palatal strut, both of
which are brief, outpatient procedures. Jaw deformities can also be
corrected.
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| Q: |
Can people with sleep apnea drive?
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| A: |
The risk of a motor vehicle accident is increased seven-fold in
the presence of sleep apnea (all other risks being equal). Once sleep
apnea is adequately treated and the person is no longer abnormally
sleepy, then driving should not be a problem. A person with sleep apnea
should notify his or her insurance company and the Department of Motor
Vehicles.
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Calculating Body Mass Index (BMI)
People who are obese
are at greater risk of developing sleep apnea than people who are a
healthy weight for their height. People with a BMI of 30 or more are
usually considered obese. BMI can be precisely calculated by dividing
your weight in pounds by the square of your height in inches and
multiplying the result by 703. However, for women, adding to 100 pounds,
5 pounds for every inch over 5 feet tall for women, or, for men, adding
to 106 pounds, 6 pounds for every inch over 5 feet tall will put you in
the center of your ideal weight.
Treating Sleep Apnea with CPAP
Continuous positive
airway pressure (CPAP) is currently considered the “gold standard”
treatment for moderate to severe obstructive sleep apnea. There is a
large variety of machines, all of which are designed to generate an
airstream that keeps the upper airway open during sleep. The choice of
machine and the level of air pressure will be determined by a sleep
specialist, usually after the patient undergoes an overnight study at a
sleep center.
Face mask options
People who use
continuous positive airway pressure may take a little time to adjust to
using their mask, but a range of different styles and designs are
available and most users are able to find one that fits well and is
comfortable to wear.
Nasal masks, the most common type, sit over the nose, where they are held in place with a strap around the head.
Full face masks
are particularly useful for patients who only breathe through their
mouth or whose breathing alternates regularly between their nose and
their mouth.
Nasal cushions or pillows
are inserted into the nostrils. They offer a useful alternative to
nasal masks for people who experience claustrophobia from masks or for
people who cannot get an ideal mask fit.
Alternatives to fixed CPAP
Occasionally,
patients may find it uncomfortable to breathe out against a fixed
pressure or CPAP may be difficult to tolerate. They may benefit from
devices designed to provide a variable pressure that automatically
adjusts to their breathing at night or from bi-level positive pressure
ventilation using a different type of machine.
Autotitrating CPAP devices
Sometimes known as
“intelligent” CPAP, these devices use a pressure sensor (or occasionally
a flow oscillation technique) to analyze air flow and adapt the
pressure to the patient’s needs over the course of the night. This
enables the device to deliver the lowest pressure necessary to maintain
an open airway, thereby making it more comfortable to use. Autotitrating
CPAP devices tend to be more expensive than fixed pressure machines,
but prices may decrease with time.
Bi-level positive pressure
This is a form of ventilation frequently used in patients who have respiratory failure ,
with or without obstructive sleep apnea. Occasionally, it is used if
CPAP alone cannot be tolerated due to the extremely high pressures
required to keep the airway open at night. Bi-level positive pressure
systems deliver a higher pressure on inhaling (breathing in) and a lower
pressure on exhaling (breathing out).
