CPAP usage proved to cause Weight Gain

Obstructive sleep apnoea is a common and serious disorder in which our breathing repeatedly stops for 10 seconds or more during sleep. The number of times that it stops per minute is referred to as the AHI index. The disorder results in decreased oxygen in the blood and can briefly awaken sleepers throughout the night.

Sleep Apnea

Mild to moderate OSA can now be treated by the use of an oral appliance, and recent NHS research from Papworth, the leading UK hospital for sleep disorders, states this quite clearly and recommends the use of a SleepPro Custom mouthpiece as the first choice in every way. Chronic sufferers must of course use CPAP – a pump and mask system that forces oxygen through the obstructed airway throughout the night.

It has been long known that obesity increases the risk for sleep apnoea and there is reasonable data demonstrating even a 10% increase in baseline weight corresponds to a > 30% increase in the AHI index and a 6 fold increase in the risk of developing moderate to severe OSA.  It is also known that the most appropriate treatment for obstructive sleep apnea is weight loss – a 10% weight loss predicts a 26% decrease in the AHI. score

The logical assumption had been that treating obstructive sleep apnea with Continuous Positive Airway Pressure would result in improved physiological parameters and help obese patients who wanted to lose weight to be more able to do so.  A new study demonstrates the opposite is true.

CPAP users showed an increase in BMI and gained weight.

While the degrees of BMI and weight gain were not large over the very short course of the research (BMI increased by over 0.13 and weight increased about 0.5 kg) the finding of any increases in both BMI and weight were highly discouraging.  Results were published in Thorax.

Sleep apnea has many different possible causes but in adults, the most common cause of obstructive sleep apnea is the excess weight and obesity mentioned above, which is associated with soft tissue of the mouth and throat. During sleep, when throat and tongue muscles are more relaxed, this soft tissue can cause the airway to become blocked.

More than half of people with obstructive sleep apnea are either already overweight or obese, which is defined as a body mass index (BMI) of 25-29.9 or 30.0 or above, respectively. In adults, excess weight is the strongest risk factor associated with obstructive sleep apnea.

Each unit increase in BMI is associated with a 14% increased risk of developing sleep apnea, and a 10% weight gain increases the odds of developing moderate or severe obstructive sleep apnea by six times. Compared to normal-weight adults, those who are obese have a sevenfold increased risk of developing obstructive sleep apnea. But the impact of BMI on obstructive sleep apnea becomes less significant after the age of 60.

BMI isn’t the sole marker of obesity that is important. Men with a neck circumference that is above 17 inches (43 cms) and women with a neck circumference above 15 inches (38 cms) also have a significantly increased risk of developing obstructive sleep apnoea.

Regardless of age, untreated obstructive sleep apnoea can lead to serious complications, including cardiovascular disease, accidents, and premature death. So it’s important that anyone with signs and symptoms of obstructive sleep apnoea, especially loud snoring and repeated night-time awakenings followed by excessive daytime sleepiness — receive a medical evaluation.

Although modest weight loss improves obstructive sleep apnoea, it can be difficult for fatigued and sleepy patients to lose weight, so it is critical to treat the problem with the use of an oral appliance as soon as possible.

John Redfern