Is Snoring A Problem? Obstructive Sleep Apnoea Explained

As scientists began to understand sleep apnoea in more depth, they started to see it as the foundation for serious illnesses affecting the whole body.

We all know that eating too many cheeseburgers, never exercising and smoking can all contribute to cardiovascular disease, but what about… snoring?

Most of us consider snoring as little more than an annoyance.

But there is some suggestion that an extreme form of snoring, known as obstructive sleep apnoea (OSA), can put you at increased risk of certain life-threatening cardiovascular conditions. 

Sleep apnoea leaves a scar beyond the daily difficulties of focus and attention that come with sleepiness

In deep sleep, the muscles of the throat relax and this may reduce the space at the back of the tongue, through which air must pass to reach the lungs.

Normally this doesn’t cause any problems with breathing.

In Obstructive Sleep Apnoea (OSA), however, complete relaxation of the throat muscles may cause blockage of the upper airway so that breathing stops temporarily. Such an episode is called an apnoea.

The lack of air causes the oxygen levels in the blood to plunge and blood pressure to jump.

Breathing stops for a few seconds and even up to one minute until the brain registers the lack of oxygen and sends a small wake-up call.

The muscle tone of the pharynx returns, this opens the airway and breathing returns to normal. 

Yet as soon as the airway is clear, the brain immediately falls back to sleep and the cycle repeats itself again and again overnight.

In severe cases, this cycle can be repeated every 1-2 minutes.

In most cases, the person suffering from sleep apnoea doesn’t even realise they are waking up. It is all so quick that it can happen more than 20 times an hour, all night long.

Patients with sleep apnoea experience a strange nightly sensation that brings the body disturbingly close to death.

It’s estimated that about five per cent of Australians suffer from this sleep disorder, with around one in four men over the age of 30 years affected.

Symptoms Of Obstructive Sleep Apnoea

Most people with OSA snore loudly and breathing during sleep may be laboured and noisy.

Sleeping partners may report multiple apnoeas lasting up to 90 seconds which often end in deep gasping and loud snorting.

Sufferers may report waking for short periods after struggling for breath.

OSA is often worse during deep sleep or when the person sleeps lying on their back. 

• Snoring
• Restless sleep
• Daytime sleepiness, fatigue and tiredness
• Morning headaches 
• Poor concentration and poor memory 
• Depression
• Irritability and mood changes 
• Impotence and reduced sex drive
• Need to get up to toilet frequently at night  
• Short temper, grumpiness, personality change
• Breathlessness either during the night or the day 
• Night- time heartburn.

OSA can be life-threatening. It is a risk factor for high blood pressure, heart attack, heart failure, and stroke. All these conditions occur more frequently in people with OSA.

Motorcar accidents have been shown to be two to five times more common in people with OSA than in other people.

What Causes Obstructive Sleep Apnoea?

OSA is far more common in men than in women. 

Women in their reproductive years seem to be protected form sleep apnoea.

This is thought to be due to sex hormone differences and their effect on muscle strength and fat distribution (men tend to gain weight around their abdomen and neck, and women around their hips). 

Obesity is the most significant risk factor for OSA, as the fat around the throat puts pressure on the upper airway. 

Obesity is also associated with many cardiovascular risk factors which, combined with OSA, can result in significant morbidity and mortality.

Obstructive Sleep Apnoea can be caused or worsened by several other factors:

• Variations in the shape of the jaw, throat, face or nose can result in some people having narrower upper airways. 
• Blocked nose, nasal ploys, small jaw, enlarged tongue, or uvula, or thyroid gland swelling may contribute to blockage of the upper airway in deep sleep.
• The use of alcohol, especially in the evening, relaxes the throat muscles, resulting in an abnormally collapsible upper airway. It also decreases arousal responses and hampers the brain’s reaction to sleep disordered breathing.
• Hayfever and smoking may lead to narrowed nose passages as well, thus aggravating sleep apnoea. 
• Medications- sleeping tablets and sedatives (benzodiazepines, anti- epileptics, corticosteroids, narcotics)
• Men are more likely to snore or have OSA than women of reproductive age. This is thought to be due to sex hormone differences and their effect on muscle strength and fat distribution. It could also be due to the higher average alcohol consumption of men.
• In children, large tonsils and adenoids are a common cause for OSA.

In Australia, 6% of patients reported visiting a doctor for a problem of sleep apnoea or snoring. 

Researchers at UCLA conducted brain scans of patients with long histories of sleep apnoea and compared them with the scans of control subjects who had normal sleep patterns. 

The investigations focused on the mammillary bodies, thought to be an important part of the memory, and have long been associated with cases of amnesia. This memory centre of the brain was 20 per cent smaller in patients with sleep apnoea.

A similar shrinkage in the size of the mammillary bodies is found in patients with Alzheimer's disease or those who experienced memory loss as a result of alcoholism.

A study found that people with untreated, severe OSA have more heart attacks and strokes than people of the same age, weight and gender who don't have sleep apnoea. 

A study in the Journal of the American Medical Association, found those who suffer from moderate to severe sleep apnea were at increased risk of having high blood pressure.

People suffering from Sleep Apnoea have a greater risk of developing a resistance to insulin which can lead to Type 2 Diabetes. Clinical studies show that people who suffer with Type 2 Diabetes often have Sleep Apnoea.

Evidence suggests that OSA is a significant risk factor for stroke and that the presence of OSA can make the recovery from a stroke more difficult.

Metabolic dysregulation such as leptin resistance and the metabolic syndrome also have been linked to OSA.

OSA also been associated with increased platelet activation, increased fibrinogen, and other potential markers of thrombotic risk. 

The repetitive hypoxemia and reoxygenation that characterize sleep in OSA patients may be implicated in the triggering of oxidative stress mechanisms.

What Can Be Done About It

OSA is usually diagnosed using clinical tests and a sleep study, where your brain activity, breathing and blood oxygen levels are measured overnight by a technician in a lab. 

Many people pause during breathing while they sleep. Interruptions (apnoeas) longer than 10 seconds up to as long as a minute, that occur five or more times an hour, indicate a mild form of OSA.

Moderate OSA is defined as between 15 and 30 apnoeas per hour, and severe OSA as more than 30 apnoeas per hour

CPAP ‘nasal continuous positive airway pressure’ machine – a mask worn at night that keeps the back of the throat open by forcing air through the nose. However, some people with sleep apnoea find the mask difficult to tolerate.

Mouthguard (or oral appliance or mandibular advancement splint) work by holding the jaw forward during sleep, effective for mild to moderate sleep apnoea.

Treatment for sleep apnoea relies on changes to lifestyle. 

• For some patients, losing weight alone can solve the problem. Even a small weight reduction can lead to improvement in symptoms of OSA.
• Musculoskeletal care (chiropractic manipulations) can improve the alinement of the neck structures and reduce nerve irritation in the area, that may be contributing to OSA.
• Denton Anti-Snore pillow can help correct sleeping posture and help unblock the airways.
• Sleeping on one's side instead of on the back, or doing exercises or playing musical instruments that build up the muscles in the throat, can also help.
• Stop drinking alcohol! Alcohol reduces the tone of the muscles in the back of your throat, decreases your natural defenses against airway obstruction and causes restless sleep.
• Avoid dairy, wheat, and grains in general, in your diet as they create inflammation and increase mucus production, which blocks the airways.
• Avoid using any sleeping tablets or tranquillisers.
• Ramp up your exercise and eat healthily to lose any excess weight.
• Stop smoking!
• Nasal obstruction due to sinus congestion may respond immediately to Sinupret.
• Drink plenty of water to keep your upper airways mucus membranes hydrated.
• Have your thyroid hormones tested to make sure that there is no Thyroid gland enlargement obstructing your throat.

If you take this path, not only will your heart thank you, your partner – and possibly the neighbours – may too.

Recommended Further Reading:

• Melt Away Body Fat The Hidden Killer
• Winning The Fight Against Nicotine
• Alcohol Addiction – Not The Way To Cope With Grief, Trauma, Or Fear

References:

Yaggi HK, Concato J, Kernan WN, Lichtman JH, Brass LM, Mohsenin V, “Obstructive sleep apnea as a risk factor for stroke and death”, N Engl J Med. 2005 Nov 10;353(19):2034-41.

Prabhakar NR. Sleep apneas: an oxidative stress? Am J Respir Crit Care Med. 2002; 165: 859–860

Suzuki YJ, Jain V, Park AM, Day RM. Oxidative stress and oxidant signaling in obstructive sleep apnea and associated cardiovascular diseases. Free Radic Biol Med. 2006; 40: 1683–1692

Coughlin SR, Mawdsley L, Mugarza JA, Calverley PM, Wilding JP. Obstructive sleep apnoea is independently associated with an increased prevalence of metabolic syndrome. Eur Heart J. 2004; 25: 735–741

Ip MS, Lam B, Ng MM, Lam WK, Tsang KW, Lam KS. Obstructive sleep apnea is independently associated with insulin resistance. Am J Respir Crit Care Med. 2002; 165: 670–676

Punjabi NM, Polotsky VY. Disorders of glucose metabolism in sleep apnea. J Appl Physiol. 2005; 99: 1998–2007

von Känel R, Loredo JS, Ancoli-Israel S, Mills PJ, Natarajan L, Dimsdale JE. Association between polysomnographic measures of disrupted sleep and prothrombotic factors. Chest. 2007; 131: 733–739.