Sleep apnoea: A common, yet frequently underdiagnosed, sleep disorder
World Sleep Day is marked on March 15 every year.

It is a day to highlight the importance of appropriately managing sleep-related diseases.

Although many diseases fall under this category, the most common (and paradoxically, one that is often underdiagnosed) is obstructive sleep apnoea syndrome (OSAS).

Airway blockage

OSAS is a sleep disorder characterised by recurrent episodes of partial or complete obstruction of the upper airway during sleep.

These tend to occur due to collapse of the soft tissue at the back of the throat, leading to a block in the airway.

The obstruction leads to pauses in breathing (known as apnoeas) or shallow breathing (known as hypopnoeas).

Although patients themselves will not notice it, those observing the patient asleep may notice loud snoring and periods of time in which the patient appears to stop breathing, followed by a snort/loud jerk and continuation of normal breathing.

This is a reflection of the brain detecting low oxygen levels and sending a trigger to open the airway.

When the interruptions to breathing occur too often during the night, normal sleep patterns will be disrupted and there will be a reduction in the flow of oxygen to vital organs.

These can lead to fragmented sleep, daytime sleepiness and potentially long-term serious health consequences.

The biggest risk factor by far for OSAS is obesity.

Fat deposits in the abdomen and around the neck can negatively affect breathing.

The National Health Screening Initiative 2023 found that more than half of the Malaysians screened were overweight or obese (31.3% overweight and 22.2% obese).

Other risk factors are linked to anatomical variations (e.g. thicker necks, narrow throats, enlarged adenoids or tonsils, or nasal septal deviation) and the use of alcohol and sedatives, which reduces muscle tone, and thus, relaxes the muscles in the throat.

The impact

Patients with OSAS often wake up feeling unrefreshed.

The condition is also characterised by excessive sleepiness during the day (such as during meetings, while driving or watching the television), morning headaches, difficulty concentrating, waking up frequently at night to urinate, fatigue and irritability.

One of the more dangerous consequences is the presence of microsleeps while driving, i.e. briefly falling asleep when at the wheel.

This is dangerous to the driver, to their passengers and to other people in the vehicle’s immediate vicinity.

In countries such as the United Kingdom, patients with uncontrolled OSAS are not allowed to drive.

The consequences are also dire over the long term.

The repeated episodes of oxygen deprivation and arousal from sleep can lead to increased blood pressure throughout the night as the body attempts to compensate for the drop in oxygen.

This can lead to sustained hypertension over time.

The cardiovascular system is also affected in other ways: OSAS is associated with an increased risk of coronary artery disease, heart failure, arrhythmias and stroke.

There is also evidence linking OSAS with type 2 diabetes mellitus, with an increase in insulin resistance and impairment in glucose metabolism.

Other potential physical consequences include abnormal liver tests and neurocognitive impairment (i.e. negatively impacting your ability to think and reason).

The above can have direct economic costs, but there are also indirect costs such as reduced work productivity and a negative impact on interpersonal relationships.

One of the most dangerous potential side effects of sleep apnoea is falling asleep at the wheel while driving, which can result in a fatal accident. — dpa

Available treatment

OSAS can be diagnosed via a sleep study.

This is where a device is attached overnight to the patient at home, which then proceeds to record the frequency of apnoea and hypopnoea, as well as other relevant markers such as snoring volume and drop in oxygen readings.

The goal of treatment is to not only improve the quality of life, but also reduce the risk of long-term complications.

These may include addressing the underlying risk factor (e.g. reduction of weight or surgical correction for anatomical causes), going to a dentist to obtain a mandibular advancement device (which helps create a wider airway), or to use a Continuous Positive Airway Pressure (CPAP) machine.

CPAP therapy involves wearing a mask connected to a machine that delivers a continuous stream of air into the airway, keeping it open when the patient is asleep.

CPAP prevents the airway from collapsing and eliminates apnoeas and hypopnoeas.

Different types of masks are available to accommodate individual preferences and anatomical variations.

Each treatment option will need to be judged on its suitability for the patient.

The CPAP machine is often the most appropriate and effective option, but it is not cheap and the vast majority of insurance companies do not provide cover for its cost, although it has a proven clinical track record in the management of OSAS.

‘Hidden’ cases

It is likely that the prevalence of OSAS in Malaysia is underreported, especially when we take into account the high levels of overweight and obese individuals.

It is also likely to be underreported due to lack of awareness, underappreciation of the seriousness of the condition, and patients getting used to having the symptoms described above as they tend to develop insidiously.

However, OSAS is a serious sleep disorder that requires prompt recognition and appropriate management to avoid both short- and long-term damage.

With advancements in diagnostic techniques and treatment modalities, individuals with OSAS can achieve significant improvement in symptoms and overall health outcomes.

By addressing OSAS effectively, affected individuals can enjoy better sleep, enhanced daytime functioning and reduced risk of associated health problems.

Dr Helmy Haja Mydin is a consultant lung specialist and CEO of the Social & Economic Research Initiative. For further information, email starhealth@thestar.com.my. The information provided is for educational and communication purposes only. The Star does not give any warranty on accuracy, completeness, functionality, usefulness or other assurances as to the content appearing in this column. The Star disclaims all responsibility for any losses, damage to property or personal injury suffered directly or indirectly from reliance on such information.
Health Matters,Sleep apnoea,sleep
You may be sleeping through this problem, but your body is unconsciously fighting to get enough oxygen.