Obstructive sleep apnea occurs when the upper airway repeatedly collapses during sleep, causing breathing pauses that last from a few seconds to over a minute and ending with a partial arousal as the brain triggers breathing to resume. The individual rarely achieves full wakefulness and often has no memory of the events, but the cumulative effect across hundreds of nightly cycles is severe sleep fragmentation, oxygen desaturation, and sympathetic nervous system activation.
How Common Is OSA?
A landmark epidemiological study published in the Lancet Respiratory Medicine in 2019 estimated that 936 million adults aged 30 to 69 have mild to severe OSA globally. In adults over 40, the prevalence exceeds 30%. The condition is substantially underdiagnosed: most epidemiological studies suggest that fewer than 20% of people with OSA have been clinically identified and treated.
Recognising the Symptoms
- Loud snoring, particularly with pauses and gasps or choking sounds
- Unrefreshing sleep despite apparently adequate duration
- Excessive daytime sleepiness: falling asleep in sedentary situations (driving, meetings, reading)
- Morning headaches from overnight carbon dioxide retention
- Waking with a dry mouth or sore throat
- Nocturia (waking to urinate): OSA-induced ANP release from atrial stretching promotes fluid excretion
- Mood changes, difficulty concentrating, memory impairment
- High blood pressure that is difficult to control with medication
The STOP-BANG Screening Tool
The STOP-BANG questionnaire is the most validated OSA screening tool for adults. Score one point for each: Snoring loudly, Tired frequently, Observed apnea by a partner, high blood Pressure; BMI over 35, Age over 50, Neck circumference over 40cm, male Gender. A score of 3 or above indicates high risk for at least moderate OSA and warrants referral for polysomnography (sleep study).
Lifestyle Management Approaches
- Weight loss: each 10% reduction in body weight produces approximately 26% reduction in apnea-hypopnea index (AHI) in overweight patients; weight loss may be sufficient for mild OSA to resolve
- Positional therapy: OSA is significantly worse in the supine (back-sleeping) position for approximately 56% of patients; positional devices or sewing a tennis ball into pyjama back are evidence-based
- Alcohol avoidance within 3 hours of sleep: alcohol reduces upper airway muscle tone and worsens OSA
- Myofunctional therapy: oropharyngeal exercises reduce AHI by approximately 50% in mild to moderate OSA (Camacho et al., 2015, Sleep)
- CPAP therapy: the standard treatment for moderate to severe OSA; reduces cardiovascular risk and daytime sleepiness effectively
Sources
- Benjafield AV, et al. (2019). Estimation of the global prevalence and burden of obstructive sleep apnoea: a literature-based analysis. Lancet Respiratory Medicine, 7(8), 687-698.
- Camacho M, et al. (2015). Myofunctional therapy to treat obstructive sleep apnea: a systematic review and meta-analysis. Sleep, 38(5), 669-675.
- Punjabi NM. (2008). The epidemiology of adult obstructive sleep apnea. Proceedings of the American Thoracic Society, 5(2), 136-143.