In Sleep Mode
Having sound, restful sleep is taken for granted. But a distorted breathing pattern can
cause loud snoring and disrupt sleep, relationships and your health.

The subject of snoring is often used in comedy routines as the butt of jokes on marital rows. The reality is that a loud snore not only puts pressure on a marriage but it can be a sign of Obstructive Sleep Apnoea (OSA), a condition that is no laughing matter.

According to Dr Hsu Pon Poh, Senior Consultant Otolaryngologist and Director of the new Integrated Sleep Service (ISS) at CGH, “treatment of snoring is easy, but the treatment of OSA is not so”.

“OSA is nothing new, but most people brush it off as a trivial problem. Over 60 per cent of the patients I see are sleeping in a separate room from their spouse. Then, there is the risk of high blood pressure, stroke and heart disease if they stop breathing during sleep. There is both a social and medical aspect to the condition,”he explains.

Breathing stops in sleep

During sleep, the brain tells the muscles of breathing to take a breath. OSA occurs when the brain sends the signal to the muscles and the muscles try to breathe but can’t because the airway is blocked. The oxygen level reaching the brain drops, so the brain signals the body to wake up in order to take a breath.

A person with OSA may not even know he has the problem because he may wake up completely, or come out of deep sleep into a more shallow level. The only sign may be the tiredness he feels the following morning from not getting enough deep sleep.

Both snoring and OSA are prevalent in people who are obese and drink a lot of alcohol, and the incidence increases with age.

Not all snorers are at risk

But not everyone who snores has OSA. Proper assessment at the ISS is therefore vital for people who have any of the symptoms that may put them at risk.

“Snoring occurs in 60 per cent of men who are over 60 years old, and around 15 per cent of them have OSA. This means that 600,000 people in Singapore could be affected. This is a public health problem,” says Dr Hsu.

Studies in the United States have found that snoring can reach 90 to 100 decibels, which is as loud as an MRT train. Very loud snoring is one of the indicators of OSA.

Another symptom is feeling tired all day. “If you need two alarm clocks to get you up in the morning, or need four or five cups of coffee to stay awake even though you’ve slept for 10 hours, then you should seek assessment,” says Dr Hsu.

He likens OSA to waking up every morning with a non-alcohol induced hangover. “That is how sluggish and below par you can feel.”

It is also easy for him to spot potential patients in the waiting room of his thrice weekly sleep clinic before he even examines them: “Everyone is snoring outside, and during consultations, I have to keep waking them up!”

Complex condition to diagnose

OSA is tricky to treat as there are many causes and modes of treatment.

Upper airway abnormalities put people at risk, says Dr Hsu. These can be enlarged tonsils, nasal obstruction that impedes airflow or floppy, ageing tongue that falls backwards and obstructs breathing.

Risk factors for any of these conditions are increasing age (because muscle tension reduces as one aged), obesity and being male. Women are at lesser risk of OSA as they have female hormones which are protective.

“It is such a complex problem because it can arise from muscle tone, blocked nose, palate or the tongue and voice box. We need to do an examination and a unique feature of our service is that we have a software that can capture and measure the dimensions of the upper airway,” says Dr Hsu.

Dr Hsu developed the Videoendoscopic Computer-assisted Measurement that is available only at CGH. This assessment technique supplies a structural diagnosis of the patient’s upper airway.

This, along with the functional test in the form of the sleep study, determines what course of treatment is suggested.

Dr Hsu sees 45 patients a week with sleep disorders in his sleep clinic, and the hospital carries out about 700 sleep studies a year. The sleep study, which monitors the airflow, muscle movement, heart, lungs and brain using sensors, is needed to show how many episodes of apnoea a patient has throughout the night, and how they affect the body.

The results range from normal (> 5 episodes of apnoea in an hour), mild (5 to 15 per hour), moderate (15 to 30 per hour) to severe (> 30 per hour).

Complex condition to treat

Treatment for OSA ranges from lifestyle modification to surgery. Depending on the diagnosis, the ISS will refer patients to the suitable speciality for appropriate treatment.

For example, for young patients with good muscle tone, weight management and exercise are often enough to treat OSA. These patients will be referred to our sports physicians.

For older patients with tissue laxity, the first line of treatment would be sleeping with a Continuous Positive Airway Pressure (CPAP) device. It delivers air through a nasal or facemask under pressure, which holds the nose, palate and throat tissues open. The CPAP machine is about the size of a toaster.

“Around 50 per cent of my patients say that their sleep is better with CPAP and stick to it. But not everyone feels comfortable wearing a mask every night,” says Dr Hsu.

For some patients with mild OSA, dental appliances that reposition the lower jaw and the tongue, thereby opening up the airway at the back of the throat, have found to be helpful.

There is also a wide range of surgical options, which include permanently removing the static obstruction like enlarged tonsils, adenoids, deviated nasal septum and cyst, and reconstructing the upper airway to treat tissue laxity.

For some patients, the cause of their sleep complaints such as insomnia and excessive daytime sleepiness may be due to psychiatric and psychological problems. These patients will be referred to the psychiatrist and psychologists.

Then, there are those with other respiratory and non-respiratory related sleep disorders such as Obesity-Hypoventilation Syndrome (OHS), Restless Legs Syndrome (RLS) and Narcolepsy. These patients will be referred to the respiratory medicine physicians.

“The way I run the service is very patient-centric. I put a lot of emphasis on patient education, the impact OSA has on their lives and what their expectations are. I’ll then tailor the treatment to suit them,” says Dr Hsu.

“OSA is a lifelong disease. It is like managing high blood pressure or diabetes. Multiple treatments could be used at the same time.”

Once treated for their OSA, Dr Hsu says his patients can be as grateful as those who have come through cancer - that is how much it changes their lives.