Obesity has long been considered one of the most important risk factors associated with heavy snoring and obstructive sleep apnoea – in particular visceral fat, a type that collects in the abdomen. Visceral fat is found in the abdominal cavity around the body’s organs and is thought of as a key trigger for both cardiovascular disease and diabetes. Although both men and women are at risk for OSA, more men than women are diagnosed with the condition, and the associated mortality rates are also considered to be higher in men.
Although Body Mass Index (BMI) and waist circumference were found to be very similar in the men and the women, it was men that had the greater degree by far of visceral fat in their abdomen. In addition, the incidence of OSA was higher in men and the degree of severity much greater. As well as producing higher cholesterol levels, this degree of visceral fat accumulation is associated with low blood-oxygen levels – often resulting in severe OSA.
On the other hand the researchers found no association in women between visceral fat accumulation and obstructive sleep apnoea. The only relationship found was with Body Mass Index – to be expected of course. Other studies have also found links between visceral fat and OSA, as well as the differences between the associated risks to men and women: Researchers at Pennsylvania State College of Medicine studied the relationship between visceral fat and OSA in non-obese men and women. In men, they found visceral fat associated with obstructive sleep apnoea. In women, visceral fat was not associated with OSA. However another type of fat—subcutaneous fat, located just beneath the skin in the abdomen and throughout the body—was associated with sleep apnoea in women.
- A study of obese men and women found that visceral fat was significantly greater in patients with obstructive sleep apnoea than those without, leading researchers to suggest that visceral fat is an important risk factor for OSA in both men and women who are obese.
- People with visceral fat accumulations and sleep-disordered breathing were significantly more likely to experience night-time acute coronary syndrome, a serious form of heart disease.
- There is some good news for obstructive sleep apnoea patients who use therapy to treat their sleep disorder: research has indicated that visceral fat in people with OSA can be significantly reduced with regular, long-term use of the common therapies – either CPAP or the more easily accepted mouthpiece or splint to wear at night.
It’s estimated that about 5% of adults in the United Kingdom suffer from OSA, but the disorder is considered significantly under-diagnosed, particularly among women. Sleep apnoea is associated with an increased risk of cardiovascular disease and diabetes, as well as certain forms of cancer. There is a significant belief showing that people with OSA who snore heavily have greater risk of earlier mortality than those without the sleep disorder, if the disorder is left untreated. There are indications within some research that men are at greater risk for mortality than women, though it’s clear that both men and women with obstructive sleep apnoea face elevated health and mortality risks compared to those without the disorder.
The stakes are high for people with obstructive sleep apnoea: the disorder is profoundly disruptive to sleep and can lead to serious health problems if not identified and treated. Understanding more specifically the health and lifestyle conditions that may increase risks of sleep apnoea can lead to better screening and treatment options. It’s also important to continue to evaluate the ways that risks for men and women may differ, and to create screening criteria and treatment protocols tailored to the needs of each. For both men and women, maintaining a healthy weight, with particular attention to abdominal fitness, is important for good sleep and good health.
By John Redfern