Understanding sleep apnea

By Carmela Tedesco | May 13, 2010 | Last updated on May 13, 2010
6 min read

Although the first detailed description of obstructive sleep apnea (OSA) only appeared in the 1960s, its characteristics were described well before this in the works of Shakespeare and Dickens.

The best known of these descriptions is Dickens’ portrayal of Joe, the sleepy fat servant boy of The Pickwick Papers (1837). ‘Fat Joe’ had such excessive daytime sleepiness that he fell asleep while knocking on a door. In the 1800s this sleep disorder was playfully known as Pickwickian syndrome, but doctors today recognize it is much more serious.

Studies demonstrate that between 2% and 4% of middle-aged adults have clinically significant sleep apnea, with a male to female ratio of 2:1, according to the Public Health Agency of Canada.

Complications include coronary heart disease, arrhythmias, stroke and hypertension. And, motor vehicle and work-related accidents may result due to the daytime sleepiness.

What is it?

Essentially sleep apnea is a sleep-disordered breathing in which there are pauses (apnea) or shallow breathing (hypopnea) during sleep.

These breathing pauses usually last 10 to 30 seconds, and can be longer in some cases.

We’ll focus on obstructive sleep apnea (OSA) which is the most common type and accounts for 95% of cases. The other types of sleep apnea are central sleep apnea, mixed sleep apnea and sleep hypoventilation syndrome.

Obstructive sleep apnea is a disorder in which there is complete or partial obstruction of the airway (nose, mouth, throat and windpipe) during sleep. Obstructive sleep apnea is one of the sleep/breathing disorders characterized by episodes of apnea (cessation of airflow exceeding 10 seconds or more) associated with hypopnea (reduction in airflow by 50% or more for 10 seconds or more, which may result in a drop in blood oxygen levels).

When the oxygen level drops, the brain then sends out signals to rouse the person from sleep, forcing them to take a breath. Typically when the breathing resumes there is a loud snort or choking sound. If there is a partial blockage of the airway any air that tries to squeeze through the narrow passage makes the snoring sound. People with OSA will follow this cycle during sleep: quiet breathing, snoring, pauses in breathing, gasping for a breath, resuming breathing. This cycle can repeat itself many times during the night and most people can have hundreds of apnea events during one night, which means constant interrupted sleep which then results in daytime fatigue and sleepiness.

What causes OSA? Obesity is the greatest risk. The extra soft fat tissue can thicken the wall of the windpipe, which then causes the airway to become blocked or narrow.

Other causes are:

  • Abnormality of the throat muscles and tongue, which relax more than normal to hold the airway open;
  • Large tongue, which blocks the airway;
  • Large uvula, which is the small piece of tissue seen dangling at the back of the tongue; or
  • Head and neck shape (bony structure)—smaller airway size in the mouth and throat area.

Other risk factors:

  • Aging – which limits the ability of brain signals to keep throat open during sleep;
  • Use of alcohol or sedatives – which relax the muscles in the throat;
  • Short, thick neck (17 inches for men and 16 inches for women);
  • Hypertension;
  • Lung disease;
  • History of sleep apnea in the family; or
  • Being male – men are twice as likely to develop OSA than women.

The frequent drop in blood oxygen levels during apnea events increase blood pressure, which increases the risk for heart attack, stroke, and low blood oxygen levels, which can bring on arrhythmia (irregular heart rhythms).

Further, reduced sleep triggers the release of stress hormones, which also increases the risk of heart attack, stroke, irregular heartbeat and heart failure from OSA. Other complications include accidents and poor concentration due to daytime sleepiness.

Diagnosing OSA

The most common symptoms of OSA are daytime sleepiness, and snoring and pauses in breathing. Other symptoms may be high blood pressure; fatigue; morning headaches; dry mouth; poor concentration, and irritability.

If a doctor suspects OSA, the confirmatory test will be the sleep study test or polysomnography (PSG), an overnight test done at a sleep centre to record brain activity, eye movements, heart rate, and blood pressure.

A PSG also records the amount of oxygen in a person’s blood; how much air is moving through his or her nose while breathing; snoring episodes; and chest movements. The test provides the apnea hypopnea index (AHI): the total number of apneas and hypopneas measured during each hour of sleep, divided by the number of hours of sleep. AHI is required by the underwriter to determine the severity of the OSA.


Mild cases of OSA respond to lifestyle changes such as weight loss, decreased alcohol consumption, smoking cessation. CPAP (nasal continuous positive airway pressure) is the preferred method for treating moderate to severe OSA. People, however, tend not to comply with the treatment because they find the machine too cumbersome. In other cases, a uvulopalatopharyngoplasty (UPPP) is a surgical treatment option for cases that result from a large uvula. Although surgery may be an option for treating OSA, the type and effectiveness of the surgery depends on the cause of the OSA.


Ratings will depend on the severity of the condition, treatment, compliance with treatment and the presence of any additional rating factors or complications.

For mild cases of OSA an APS may be avoided if the underwriter has sufficient information to determine the condition is mild, and that there is an absence of any other risk factors such as a history of high blood pressure, heart disease, stroke, arrhythmia or any other respiratory disorder. A classification of mild is defined as mild snoring, no pauses in breathing, no shallow breathing and no daytime sleepiness. A mild case of OSA may be assessed standard for life and critical illness in the absence of any risk factors including daytime sleepiness and an adverse driving record.

An APS will always be required if there was either surgery or CPAP treatment. It also will be required in the presence of OSA in the elderly, or OSA in people with any other risk factor including an adverse driving record or if there have been work related injuries.

A moderate to severe case of OSA may be assessed at standard to moderately substandard for life coverage depending on the sleep study and AHI results, how long a person has been on treatment, compliance with treatment and no other risk factors or adverse history. A case will be declined for life coverage if OSA is suspected but no sleep study has been conducted, or if there is non compliance with treatment or poor sleep study results.

For critical illness, the underwriting assessment will be favourable for moderate/severe if there has been good response to treatment for at least one year, good compliance with treatment, favourable sleep study results, and no risk factors in a non smoker.

How to expedite the Underwriting?

If your client is not on treatment with CPAP or has not been diagnosed with OSA or in cases where your client has been told by his doctor he has mild OSA, include the following information with the application:

  • Do you snore?
  • Has your spouse noticed you gasping while you sleep?
  • Has your spouse noticed any pauses in your breathing?
  • Do you have daytime sleepiness or fatigue?
  • Do you wake up feeling refreshed?
  • Do you wake up with a dry mouth?
  • Do you fall asleep at inappropriate times?
  • Have you had motor vehicle accidents where you were at fault?
  • Do you have high blood pressure?

If your client has been diagnosed with OSA, include the following information with the application:

  • When was his or her last sleep study?
  • Does he or she use a CPAP machine every night?
  • Has the client’s spouse noticed an improvement in sleep habits since the CPAP?
  • Has the client noticed any improvement in symptoms since using the CPAP?
  • If your client has been assessed at substandard, is a reconsideration possible?
  • If your client was rated for OSA for life or critical illness coverage, a reconsideration of a rating is possible if he or she has been compliant with treatment for over one year and a current sleep study report shows favourable results using CPAP.

If your client has made some lifestyle changes due to a diagnosis of OSA, such as weight loss and has maintained this weight loss for one year or has decreased alcohol consumption and the improvements in the OSA symptoms are documented by a physician, a rating reconsideration can be requested.

Keep in mind that a rating reconsideration is always subject to no other change in insurability regardless of whether the condition for the rating has improved.

  • Carmela Tedesco is VP of Underwriting Services at LOGiQ3 Inc., and provides audit, consulting, outsourcing, and underwriting solutions to the North American insurance and reinsurance industry.

    Carmela Tedesco