When fluid in tissues is displaced from the lower body into the upper body, the circumference of the neck grows, which may hinder the flow of air, also explaining the prevalence of obstructive sleep apnea.
These findings may help explain why the prevalence of obstructive sleep apnea (OSA) is increased in patients with diseases characterized by ”fluid overload,” like heart failure and kidney failure, for example.
People with sleep apnea stop breathing temporarily and repeatedly while asleep causing them to gasp for breath.
Although obesity and a thick neck are risk factors for the disorder, they account for only about one third of variability in the apnea hyperpnoea index — a measure of the frequency of slow or stopped breathing Episodes at night.
Dr T Douglas Bradley, from the Toronto General Hospital, and his team theorized that fluid accumulation in soft tissues in the neck might cause narrowing or blockage of the pharynx — the tube that connects the mouth and nasal passages with the esophagus.
Experiments in 11 healthy non-obese subjects with no symptoms suggesting OSA support this line of thinking.