Sleep Apnea & Breathing Disorders: What You Need to Know
Millions of people stop breathing dozens — sometimes hundreds — of times every night without knowing it. A pulmonologist explains what sleep apnea really is, why it matters far beyond snoring, and what modern treatment can do.
The patient sitting across from me had spent three years telling himself he was just a loud snorer. His wife had moved to the spare room. He fell asleep at traffic lights twice. He put his exhaustion down to a demanding job and the pressures of middle age. When we finally did a sleep study, he was stopping breathing 47 times an hour.
This is not an unusual story. Sleep apnea is one of the most underdiagnosed conditions in medicine — not because it is subtle, but because its symptoms are so easy to normalise. Tiredness, snoring, poor concentration — these are things we tend to blame on busy lives rather than a medical condition that, left untreated, carries serious long-term consequences for the heart, the brain, and overall health.
This article covers everything you need to understand about sleep apnea and sleep-related breathing disorders: what they are, why they happen, what the warning signs look like, and what the treatment landscape looks like today.
What Is Sleep Apnea?
Sleep apnea is a condition in which breathing repeatedly stops and starts during sleep. Each pause — called an apnea — typically lasts between 10 and 30 seconds, though some extend longer. The brain eventually registers the drop in oxygen and rouses the person just enough to restart breathing, usually with a gasp or snort. This happens so briefly that most people have no memory of it in the morning.
The problem is that these micro-arousals prevent the deep, restorative stages of sleep. The body never fully recovers. And every apnea episode causes a temporary drop in blood oxygen and a spike in blood pressure — repeated hundreds of times a night, night after night, this places enormous cumulative strain on the cardiovascular system.
There are three distinct types of sleep apnea, each with a different mechanism and requiring a different approach to treatment.
Obstructive Sleep Apnea (OSA)
By far the most common form, obstructive sleep apnea occurs when the muscles at the back of the throat relax during sleep, allowing the soft tissues — the tongue, soft palate, and uvula — to partially or completely block the airway. Air cannot pass through normally, breathing effort increases, and eventually the person wakes briefly to restore airflow. OSA is the type most people mean when they refer to "sleep apnea."
Central Sleep Apnea (CSA)
Central sleep apnea is less common and has a fundamentally different cause. Here the airway is not blocked — instead, the brain fails to send the correct signals to the breathing muscles. There is no obstruction; the body simply does not attempt to breathe for a period. CSA is more commonly associated with heart failure, stroke, high altitude, and the use of opioid medications.
Complex (Mixed) Sleep Apnea
Some patients have a combination of both obstructive and central components. This is called complex or mixed sleep apnea and requires careful specialist management, as treating the obstructive element alone can sometimes unmask or worsen the central component.
Recognising the Warning Signs
The challenge with sleep apnea is that its primary events — the breathing pauses — happen while you are asleep and unconscious. Most patients are entirely unaware of them. What they notice are the daytime consequences, which are often chalked up to other causes.
Falling asleep during meetings, while watching television, or even briefly while driving. This is the hallmark symptom — and one of the most dangerous.
Often reported by a bed partner. Not all snorers have sleep apnea — but snoring accompanied by witnessed pauses is a strong indicator.
A partner observing the person stop breathing, followed by a choking or gasping sound, is one of the most reliable clinical indicators of OSA.
Caused by elevated carbon dioxide levels during apnea episodes. Headaches that are present on waking and clear within an hour are characteristic.
Fragmented sleep prevents proper cognitive consolidation. Patients frequently describe difficulty concentrating, forgetfulness, and mental fog.
Chronic sleep deprivation has predictable effects on mood — irritability, low frustration tolerance, and symptoms of depression are all common.
Frequently overlooked, waking two or more times per night to urinate is a recognised symptom of sleep apnea, caused by hormonal changes during apnea events.
The effort of breathing against a partially blocked airway generates significant physical exertion, often resulting in sweating and restless, non-refreshing sleep.
The patients I worry about most are not the ones who come in snoring loudly — they are the ones who have simply accepted feeling exhausted as their new normal. If you cannot remember the last time you woke up feeling genuinely rested, that deserves investigation.
— Dr. Nabila Zaheer, Pulmonologist
Who Is at Risk?
Sleep apnea does not affect all people equally. While it can occur in anyone — including children — certain characteristics significantly raise the likelihood.
Key Risk Factors
- Excess weight — Fat deposits around the upper airway narrow the breathing passage and increase the likelihood of collapse during sleep. Obesity is the single strongest modifiable risk factor for OSA.
- Male sex — Men are two to three times more likely to develop OSA than pre-menopausal women. After menopause, women's risk rises considerably and approaches that of men.
- Age — Risk increases progressively with age. The muscles that support the airway naturally lose tone over time.
- Neck circumference — A neck circumference above 40cm in women and 43cm in men is associated with increased OSA risk, reflecting the amount of soft tissue surrounding the airway.
- Anatomical factors — A narrow jaw, enlarged tonsils, a large tongue, or a recessed chin can all contribute to airway crowding during sleep.
- Family history — OSA clusters in families, suggesting a genetic contribution to airway anatomy and respiratory control.
- Alcohol and sedatives — These relax the throat muscles further, worsening airway collapse during sleep.
- Smoking — Causes airway inflammation and increases the likelihood of upper airway dysfunction.
- Nasal congestion — Chronic nasal obstruction from allergies or structural issues forces mouth breathing, which increases airway vulnerability during sleep.
Why Untreated Sleep Apnea Is Dangerous
Sleep apnea is not simply a sleep quality problem. The repeated cycles of oxygen deprivation and blood pressure spikes during apnea events cause systemic damage that extends well beyond feeling tired in the morning.
The cardiovascular consequences are particularly significant. Untreated moderate-to-severe OSA is associated with a substantially increased risk of high blood pressure — and crucially, it is one of the most common causes of hypertension that does not respond adequately to medication. If your blood pressure is difficult to control despite multiple medications, sleep apnea should be investigated as a contributing factor.
Beyond blood pressure, untreated sleep apnea is linked to increased risk of heart attack, atrial fibrillation, stroke, and heart failure. The metabolic consequences include worsening insulin resistance and type 2 diabetes. There is also growing evidence of links between untreated sleep apnea and cognitive decline, including increased dementia risk with long-term exposure.
And then there is the immediate, practical danger: drowsy driving. Patients with untreated sleep apnea are significantly more likely to be involved in road traffic accidents. This is not a theoretical risk — it is one of the most compelling reasons to diagnose and treat this condition promptly.
How Is Sleep Apnea Diagnosed?
Diagnosis has become considerably more accessible in recent years. Where previously a full in-laboratory sleep study was the only option, home-based testing now allows many patients to be diagnosed in the comfort of their own beds.
Home Sleep Apnea Test (HSAT)
A home sleep test involves wearing a small monitoring device overnight that records breathing effort, airflow, oxygen levels, and heart rate. It is appropriate for most patients with a straightforward clinical picture of suspected OSA and can be arranged quickly and conveniently. Results are analysed by a sleep physician and typically returned within a few days.
In-Laboratory Polysomnography (PSG)
A full overnight sleep study in a specialist sleep laboratory remains the gold standard for diagnosis. It records brain activity, eye movements, muscle tone, heart rhythm, breathing patterns, and oxygen levels simultaneously, providing a comprehensive picture of sleep architecture and breathing events. It is particularly important when central or complex sleep apnea is suspected, when the home test is inconclusive, or when other sleep disorders need to be assessed alongside OSA.
The AHI Score
Results are expressed as an Apnea-Hypopnea Index (AHI) — the average number of breathing events per hour of sleep. An AHI below 5 is normal. Between 5 and 14 is mild OSA. Between 15 and 29 is moderate. An AHI of 30 or above is severe OSA, meaning the patient is experiencing at least one breathing disruption every two minutes throughout the night.
Treatment Options: What Works
The good news about sleep apnea is that it is highly treatable. The right treatment depends on the type and severity of the condition, the patient's anatomy, their preferences, and any contributing factors that can be addressed.
Continuous Positive Airway Pressure (CPAP) is the most effective treatment for moderate-to-severe OSA. A small machine delivers a continuous stream of pressurised air through a mask worn during sleep, acting as a pneumatic splint that holds the airway open. When used consistently, CPAP eliminates apnea events, restores normal sleep architecture, reduces blood pressure, improves daytime alertness, and significantly lowers cardiovascular risk. Modern CPAP machines are quiet, compact, and far more comfortable than older generations of the technology.
A custom-fitted oral appliance worn during sleep that gently repositions the lower jaw and tongue forward, enlarging the airway space. MADs are particularly effective in mild-to-moderate OSA and in patients who cannot tolerate CPAP. They are fitted by a dentist with specialist training in sleep medicine and adjusted gradually to optimise effectiveness.
In patients whose OSA occurs predominantly or exclusively when sleeping on their back, positional therapy — using devices that encourage side sleeping — can produce a clinically meaningful reduction in apnea events. It is often used as an adjunct to other treatments rather than a standalone solution.
In overweight and obese patients, weight reduction is one of the most effective ways to reduce OSA severity — and in some patients, significant weight loss can result in complete resolution of the condition. Even modest weight loss of 10 percent of body weight can produce meaningful improvements in AHI. Bariatric surgery in appropriately selected patients with severe obesity has been shown to dramatically reduce or eliminate OSA.
Surgery is considered when anatomical abnormalities are contributing to airway obstruction, or when CPAP and MAD have been tried and have failed or cannot be tolerated. Procedures range from tonsillectomy and adenoidectomy (particularly in children) to more complex palatal or jaw surgery in adults. Hypoglossal nerve stimulation — an implantable device that stimulates the tongue nerve during sleep to prevent airway collapse — is a newer option showing considerable promise in carefully selected patients.
Central sleep apnea requires a different approach, focused on the underlying cause. In patients with heart failure, optimising cardiac treatment often improves CSA significantly. Adaptive Servo-Ventilation (ASV) — a specialised form of ventilatory support that adjusts breath-by-breath to stabilise breathing patterns — is effective in certain forms of CSA, though it requires careful patient selection.
Living Well With Sleep Apnea
A diagnosis of sleep apnea — particularly when CPAP is prescribed — is one that patients sometimes resist. The idea of wearing a mask to bed feels strange or intrusive. Some patients try it for a few nights, find it uncomfortable, and quietly put the machine away.
I want to address this directly. The adjustment period for CPAP is real — most patients need two to four weeks before it feels natural. During this period, the benefits of treatment often become strikingly apparent: patients describe waking up feeling refreshed for the first time in years, concentration improving, energy returning, their partner sleeping in the same room again. These are not minor quality of life improvements — they are transformations.
If you are struggling with CPAP, the answer is not to stop using it. It is to speak to your sleep medicine team about mask fit, pressure settings, or whether a different interface might suit you better. The technology has advanced enormously, and the right setup makes compliance far more achievable than older patients who struggled with first-generation equipment may remember.
Beyond treatment, the following lifestyle measures all support better outcomes in sleep apnea:
- Maintaining a healthy body weight or working towards gradual, sustainable weight loss
- Avoiding alcohol, particularly in the three hours before bed
- Sleeping on your side rather than your back where possible
- Treating nasal congestion or allergies that contribute to airway obstruction
- Keeping all follow-up appointments — sleep apnea requires ongoing monitoring, not just a one-time diagnosis
Frequently Asked Questions
Can children have sleep apnea?
Yes. Paediatric OSA is more common than many parents realise, and its presentation in children differs from adults. Rather than excessive daytime sleepiness, children with OSA often present with behavioural problems, poor school performance, hyperactivity, and bedwetting. Enlarged tonsils and adenoids are the most common cause in children, and surgical removal frequently resolves the condition completely.
Is snoring always a sign of sleep apnea?
Not always. Simple snoring — without apnea events — is common and not medically dangerous in itself, though it can significantly disrupt a partner's sleep. However, loud snoring accompanied by witnessed pauses, gasping, choking sounds, or significant daytime sleepiness is strongly associated with OSA and should be investigated. If in doubt, a sleep study is the only way to know for certain.
Does sleep apnea ever go away on its own?
In most adults, OSA does not resolve spontaneously. It is a structural and physiological condition that typically persists and may worsen gradually over time without treatment. Significant weight loss in overweight patients can produce substantial improvement and occasionally full resolution. In children, treating the underlying cause — such as removing enlarged tonsils — often resolves OSA completely.
Do I have to use CPAP forever?
For most patients, CPAP is an ongoing treatment rather than a short-term fix — because the condition it treats is ongoing. However, if significant weight loss occurs or other contributing factors are addressed, it is entirely appropriate to repeat a sleep study to reassess whether CPAP is still required at the same settings, or at all. Some patients who achieve substantial weight loss are able to discontinue CPAP under the guidance of their sleep physician.
Can I drive if I have sleep apnea?
This is an important question with both medical and legal dimensions. Untreated sleep apnea that causes excessive daytime sleepiness may impair driving ability and in many jurisdictions carries a legal obligation to inform the relevant licensing authority. Once effectively treated and daytime sleepiness has resolved, most patients can drive normally. Your pulmonologist can advise you on the specific requirements in your region and confirm when it is safe and legally appropriate to drive.
Sleeping Poorly? Do Not Ignore It.
If you recognise the symptoms in this article — or someone you live with has raised concerns about your breathing at night — the right step is a proper sleep evaluation. Book a consultation with Dr. Nabila Zaheer today.
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