‘I diagnose sleep disorders - this is the one symptom people always miss’, says sleep scientist

Many of us wake up at night. It could be perimenopausal night sweats, insomnia, a partner's snoring, or stress. Whatever the reason, few of us are getting good quality core sleep. At best, this is frustrating. At worst, it can lead to health problems.

One common sleep condition is sleep apnea. This is when your breathing stops and starts during sleep. It happens if the airway becomes blocked or collapses, and it can lead to snoring, gasping and a feeling of exhaustion the next day. Dr David Garley, GP and director of The Better Sleep Clinic, says the condition could affect up to eight million people in the UK, but “around 85% of cases remain undiagnosed and untreated because the symptoms of sleep apnea are subtle or mistaken for something else”.

One of sleep apnea's earliest symptoms is very frequently missed by sufferers, and instead is put down to other causes - including bad pre-sleep habits and age. This symptom is night-time urination, otherwise known as 'nocturia'.

What is nocturia?

Put simply, nocturia is getting up to use the loo in the middle of the night - and it's a sign of sleep apnea that often goes unrecognised. “For many people, nocturia appears before they recognise classic sleep apnea signs like loud snoring, which is why they don’t automatically associate nocturia with a sleep disorder,” says Dr Garley.

Sleep apnea prevents our normal nighttime release of antidiuretic hormone (ADH), which our body produces to stop us from needing to pee at night. If your sleep is disrupted by snoring or gasping for breath, it impacts your ADH production, which can lead to nocturia.

“Apneic episodes also trigger the sympathetic nervous system (SNS), which is responsible for the body’s ‘fight or flight’ response. In turn, this can increase bladder sensitivity or urgency, leading to nocturia,” explains Dr Garley.

He emphasises that it’s possible to have nocturia without sleep apnea. “However, when combined with symptoms like daytime tiredness, morning headaches, snoring, waking unrefreshed, or concentration problems, you should consider seeking advice from a healthcare professional,” he says.

The reason so many cases of sleep apnea go undiagnosed is that we may not know how our bodies are behaving while we sleep. While many fitness trackers accurately record our sleep habits these days (including the latest Apple Watch 11 and the Oura Ring 4), Dr Garley says it's often partners that tell sufferers if they’ve spotted some of the symptoms.

How to treat sleep apnea

• Weight management: Being overweight, especially around the neck, can cause your airway to narrow, causing breathing issues. Losing weight can help resolve sleep apnea and other sleep disorders.
• Sleeping on your side: Dr Garley says sleeping on your back “worsens airway collapse”, so side sleeping is recommended for people with sleep apnea. If you’re not used to this position, you could try using a pillow for side sleepers or a wedge to support your hips and lower back.
• Oral devices – a mandibular advancement device is a bit like a gum shield that can be worn at night to move your lower jaw forward and keep your airway open.

If your sleep apnea is moderate or severe, Dr Garley says you may need medical treatment. This could include Continuous Positive Airway Pressure (CPAP) therapy, where you wear a mask at night to deliver a steady flow of oxygen to your body. Using a machine like this can help improve your sleep and your daytime energy levels and reduce your risk of other health problems, such as cardiovascular disease and high blood pressure.

For personal guidance on sleep apnea and general sleep, speak to your doctor.