How Does Weight Loss Play a Role in Obstructive Sleep Apnea

In Singapore, the percentages of the adult population who are overweight are around 32% for men and 22% for women. And according to the Health Promotion Board, 1 in 10 Singaporeans between 18 to 69 years old is obese. While excess weight puts one at risk for a number of health conditions, it is also the strongest risk factor that’s associated with Obstructive Sleep Apnea (OSA). In fact, it was found that over half of the people who have OSA are overweight or obese.

Let’s explore more on the link between weight and OSA, and how losing weight can have a significant effect in managing the condition.

The risk of having OSA increases with weight

 OSA is a disorder in which breathing is interrupted or stopped repeatedly during sleep. This brief pause in breathing can last for at least 10 seconds. It occurs when the muscles around the upper airway (or breathing passage) relax and partially or completely block the upper airway for a short period of time during sleep.

Putting on the extra pounds increases the chance of having the disorder because there will be more fat tissues around the neck and throat region, causing a narrower breathing passageway and makes it susceptible to collapse during sleep. Those with a larger neck circumference (more than 17 inches for men and 16 inches for women) may have excess fat deposits near the upper airway that can obstruct breathing. When the air has to squeeze through the narrowed or blocked airway, it is often heard as snoring, gasping or snorting.

A vicious cycle between weight gain and the lack of sleep

Having adequate and uninterrupted sleep will keep you feeling well-rested, but adults with OSA may experience impaired concentration, fatigue, and excessive sleepiness during daytime. Poor sleep quality due to OSA can contribute to weight gain and lower energy levels. If you’re constantly fatigued and feeling tired, you might not have the motivation and energy to engage in physical activities. Therefore, it can be more difficult for people with OSA to lose weight, and at the same time, having excess weight will cause breathing difficulties during sleep. Thus, the cycle continues.

A definitive sleep study is needed to diagnose and determine OSA. This involves a consultation with an ENT specialist who will take your medical history and conduct a physical examination. The sleep study will monitor and record the body’s activity during sleep overnight, including breathing patterns, brain waves, heart rate and limb movements. This can be done at home, in a sleep laboratory or in a hospital.

The gold standard for managing OSA is using Continuous Positive Airway Pressure (CPAP) therapy – a mask-like device that is worn throughout the night during sleep. A machine pumps air through the tube and mask worn on the nose or face, creating “positive pressure” to keep the upper airway open and helps prevent snoring. When sleep apnoea is managed and under control, you can gain better quality of sleep and have more energy to exercise and lose weight.

Does OSA go away after weight loss?

For those who are overweight, losing the excess weight and maintaining an ideal BMI can help control sleep apnoea. The ideal BMI for Asians should be less than 23.5. Losing weight does help reduce or improve the severity of OSA in overweight patients.  However, if there are other underlying structural cause for your OSA (e.g. large tonsils and adenoids, persistent nasal blockage), weight loss alone will not cure your sleep apnoea.

An ENT specialist will assess your condition to determine the likely cause of OSA and recommend the appropriate treatment. If left untreated, it increases the risk of serious complications such as hypertension and heart disease. If you think you might have OSA, consult with an ENT doctor for your snoring issues.

Medically reviewed by Dr Gan Eng Cern