What is Sleep Apnea? The Condition that Nearly Killed Me

My wife knew something was wrong from the very beginning.

Early in our relationship, she’d lie awake listening to me snore. Not normal snoring, but something that sounded broken. Loud gasping. Long pauses where I’d stop breathing entirely. Then a desperate gasp for air, like I was drowning.

“You need to get that checked out,” she’d say.

I brushed it off. I’ve always been a heavy snorer. It’s not a big deal.

But it was a big deal. The migraines came in waves, debilitating and crushing, forcing me to spend entire days in a darkened room with the curtains drawn, waiting for the nausea to build until I finally vomited and found temporary relief. Then came the exhaustion. Deep, unshakeable fatigue that no amount of sleep could fix. I’d lie in bed for eight or nine hours and wake up feeling like I’d been hit by a truck.

My wife watched me deteriorate, knowing something was seriously wrong but not knowing what. Neither did I.

When I finally got tested, the diagnosis was severe obstructive sleep apnea. What she’d been hearing at night wasn’t just snoring. It was hundreds of times every night when my breathing stopped entirely, my oxygen plummeted, and my body jolted itself back toward consciousness to survive. All while I slept unaware.

If you’re wondering what sleep apnea actually is, this is what I wish I’d understood years before I was diagnosed.

What Is Actually Happening

Sleep apnea is a sleep disorder where your breathing repeatedly stops during sleep. The name comes from the Greek word for “without breath.” Each pause, called an apnea event, typically lasts ten seconds or more. Some stretch to thirty seconds or longer.

During these events, blood oxygen drops. The brain detects the danger and partially wakes you to restart breathing, often with a gasp, a snort, or a jolt upright. Then you fall back asleep and the cycle repeats. Dozens of times a night. Sometimes hundreds.

You’re probably not conscious of these awakenings. I certainly wasn’t. But your body experiences each one as a small emergency, flooding your system with stress hormones and preventing you from reaching the deep restorative sleep stages where physical and cognitive recovery actually happens. The result is that you wake up genuinely exhausted despite having technically been asleep for a full night, and if this goes on for months or years, the accumulated damage to your health is significant.

Estimates suggest that around 39 million American adults have obstructive sleep apnea, and the vast majority don’t know it. That last part is the dangerous part.

The Three Types

Understanding which type of sleep apnea is involved matters because the causes and treatments differ.

Obstructive sleep apnea accounts for the large majority of cases and is what I have. The problem is mechanical. During sleep, when the throat muscles relax, the soft tissue of the airway collapses inward and blocks the passage of air. The brain is still trying to breathe, the respiratory muscles are still making effort, but air cannot get through. The hallmark sound is what my wife described: loud snoring, then silence as breathing stops, then a gasp as the airway reopens and the cycle begins again.

Central sleep apnea is less common and works differently. The airway isn’t blocked. The problem is that the brain fails to send the correct signals to the respiratory muscles. Breathing pauses not because air can’t get through but because the instruction to breathe simply doesn’t arrive. This type is more often associated with heart failure, stroke, and certain neurological conditions.

Complex sleep apnea involves both obstructive and central components occurring together. It sometimes emerges only after starting CPAP treatment for obstructive sleep apnea, which is one reason why ongoing monitoring after starting therapy is important.

The Warning Signs I Missed

Looking back, the signs were everywhere. I just didn’t connect them to a breathing problem during sleep.

The nighttime symptoms are usually the ones a partner notices first. Loud chronic snoring punctuated by silence and then gasping is the most recognisable pattern. Waking frequently during the night, night sweats, and jolting awake choking or struggling for air are all worth taking seriously. If a partner has ever told you that you appear to stop breathing during sleep, that observation alone is enough reason to get assessed without waiting for other symptoms to accumulate.

The daytime symptoms are what I lived with for years without understanding their cause. The morning headaches were my most prominent sign, crushing migraines that took hours to resolve and were caused by the overnight oxygen deprivation and carbon dioxide buildup. Waking feeling unrested despite what should have been adequate sleep hours was another consistent experience. The brain fog, the difficulty concentrating, the forgetting of conversations I’d had hours earlier, the sense of moving through the day at reduced capacity: these are all recognisable symptoms of a brain that’s been repeatedly deprived of oxygen and proper restorative sleep.

Irritability and mood changes are underappreciated symptoms too. Chronic sleep disruption affects emotional regulation, and I was shorter with the people around me than I should have been and than I wanted to be, for reasons I couldn’t explain at the time.

If several of these descriptions sound familiar, particularly the combination of snoring with persistent daytime exhaustion, getting tested is the right next step rather than continuing to attribute the symptoms to stress, age or personality.

Why Untreated Sleep Apnea Is Serious

Before my diagnosis, I genuinely thought sleep apnea was mainly an inconvenience: annoying for bed partners, mildly embarrassing, but not something to particularly worry about. That understanding was wrong.

Every time breathing stops, oxygen levels drop, and blood pressure spikes. The heart races. Stress hormones flood the system. Blood vessels constrict. When this happens dozens or hundreds of times every single night, the cumulative strain on the cardiovascular system is substantial. Untreated sleep apnea is an independent risk factor for hypertension, heart attack, stroke, and atrial fibrillation. The American Heart Association has formally recognised this connection.

The metabolic effects are similarly significant. Sleep apnea interferes with insulin regulation, increasing the risk of type 2 diabetes and making existing diabetes harder to manage. The disruption of appetite hormones drives weight gain, which in turn worsens the sleep apnea itself, creating a cycle that’s difficult to break without treating the underlying condition.

The cognitive consequences I’ve covered in detail in my brain fog article, but the summary is that chronic overnight oxygen deprivation causes measurable changes in brain structure, particularly in regions involved in memory and decision-making. These changes are partially reversible with treatment but accumulate with time, which is the argument for taking symptoms seriously early rather than waiting.

The accident risk is something I think about now when I remember falling asleep at red lights before my diagnosis. People with untreated sleep apnea are significantly more likely to be involved in motor vehicle accidents due to excessive daytime sleepiness. I was lucky that my particular experience of this didn’t cause serious harm.

The honest answer to the question of whether sleep apnea can kill you is yes, both from the direct cardiovascular consequences and from the accumulated long-term damage. Treatment with CPAP dramatically reduces all of these risks. That’s what finally made me take it seriously.

Getting Diagnosed

I avoided getting tested for years. Part denial, part embarrassment, part a vague fear of what I might find out. What pushed me to act was my wife, who eventually told me in terms that left no room for further procrastination that I needed to get tested.

The first step is a conversation with your GP. Describe your symptoms and, if a partner has witnessed your breathing during sleep, bring them or at least ask them to write down what they’ve observed. That eyewitness information is clinically valuable. Your doctor will assess your risk and, if they suspect sleep apnea, refer you for a sleep study.

The gold standard is an overnight study in a sleep lab, where a full range of measurements are taken including brain activity, oxygen levels, heart rhythm, breathing patterns and body movement. It’s comprehensive and provides the most complete picture of what’s happening during your sleep. My own experience of it was that lying there connected to sensors felt strange but was not as difficult as I’d anticipated, and the results were unambiguous.

For many people now, an at-home sleep test is a viable alternative that’s more accessible and considerably less daunting. These tests measure fewer parameters than a full lab study but can reliably diagnose obstructive sleep apnea in most straightforward cases. The device I recommend and have reviewed in detail is the WatchPAT One: it’s FDA-cleared, clinically accurate, and you wear it on your wrist at home for a single night before mailing it back. Results come within days and are sufficient to diagnose and prescribe treatment. If the idea of sleeping in a lab has been the thing stopping you from getting tested, a home test removes that barrier entirely.

The results of your sleep study will include an apnea-hypopnea index, which measures the average number of breathing events per hour of sleep. This figure determines whether your sleep apnea is mild, moderate or severe and guides what treatment is recommended. Your oxygen saturation levels during sleep are another important part of the picture, showing how significantly the events are affecting your blood oxygen.

Treatment

The treatment that changed my life is CPAP therapy. Continuous Positive Airway Pressure works by delivering a steady stream of pressurised air through a mask worn during sleep, maintaining enough pressure in the airway to prevent it from collapsing. The machine doesn’t breathe for you: it simply keeps the passage open so you can breathe normally on your own.

I won’t pretend the adjustment period is easy. The first few nights feel strange. The mask is unfamiliar, the air pressure takes getting used to, and the instinct to remove it during the night is real. I’ve written separately about getting used to CPAP and your first night because the adjustment period is when most people consider giving up. Don’t. The benefits that accumulate with consistent use are significant enough to be worth that initial difficulty.

Within a fortnight of starting therapy, my morning migraines had largely stopped. Within a month, I could think clearly again. My wife stopped lying awake worrying. Over the following months, I understood more and more clearly how much the untreated condition had been affecting me, because I could feel the difference between that version of my life and this one.

For mild to moderate sleep apnea, oral appliances designed to advance the lower jaw during sleep are a legitimate alternative to CPAP for people who can’t tolerate the machine, though they’re less effective for severe cases. Positional therapy helps people whose apnea is significantly worse in certain sleep positions. Weight loss improves severity, sometimes dramatically, though for those with severe structural sleep apnea, it rarely eliminates the need for treatment. Surgical options exist for specific anatomical causes and are worth discussing with an ENT if other treatments haven’t worked.

The right treatment depends on the type and severity of your sleep apnea, your anatomy, and what you can realistically sustain long-term. A sleep specialist is the right person to have that conversation with, informed by the results of your sleep study.

What I’d Tell My Earlier Self

The version of me who brushed off my wife’s concerns, who normalised the migraines and the exhaustion, who kept finding reasons not to get tested: I’d tell him that everything he was attributing to getting older, to stress, to just being someone who doesn’t sleep well, had a specific cause and a specific treatment. That the test was worth doing. That the machine, strange as it seemed in prospect, would become as routine as anything else in his life and would give him back a quality of thinking and living he’d been quietly losing for years.

If any of this has sounded like your experience, the most useful thing you can do today is book an appointment with your GP and describe what’s been happening. Sleep apnea is one of the most common serious sleep disorders and one of the most underdiagnosed. The gap between those two facts is the gap where people are living diminished lives without knowing why.

You don’t have to.

⚠️ MEDICAL DISCLAIMER This blog provides general information only and is not a substitute for professional medical advice, diagnosis, or treatment. Sleep apnea is a serious condition, and CPAP equipment should be used under proper medical supervision. Always consult your doctor or sleep specialist before starting, stopping, or changing any therapy. I share personal experiences as a CPAP user, not as a medical professional. Individual results vary. For medical guidance, please consult a qualified clinician or the American Academy of Sleep Medicine (aasm.org).