Throat problems could impair the autonomic nervous system's ability to regulate blood pressure, according to new research.

The study, led by the University of Southampton, suggests that issues at the junction between the air and food passages may overwhelm the vagus nerve.

This could result in patients with throat problems being less able to regulate their blood pressure.

The study, published in JAMA Otolaryngology, is the first to observe reduced baroreflex sensitivity in patients with throat symptoms.

The baroreflex is a critical part of the autonomic nervous system that detects changes in blood pressure and adjusts the heart rate and blood vessel tone to maintain stable blood pressure.

It also prevents fainting when standing up.

Researchers from the University of Southampton and University Hospitals of Dorset Foundation Trust believe the findings could be explained by the vagus nerve, which controls the autonomic nervous system, prioritising the protection of the airways over less urgent functions, such as blood pressure regulation.

Reza Nouraei, professor of laryngology and clinical informatics at the University of Southampton and lead author of the study, said: "Our immediate survival depends on the throat being able to separate air and food passages each time we swallow.

"The throat does this using delicate reflexes, but when these reflexes are disturbed, for example, due to a viral infection like Covid or exposure to reflux affecting nerves in this region, the control of this critical junction becomes compromised, giving rise to symptoms like the feeling of a lump in the throat, throat clearing, and coughing."

The researchers compared the heart rates, blood pressure, and baroreflex sensitivity of 23 patients admitted to ear, nose, and throat (ENT) surgery with aerodigestive (laryngopharyngeal) symptoms and 30 patients admitted to gastroenterology with digestive (esophagogastric) symptoms at University Hospitals of Dorset NHS Foundation Trust.

The team found that patients in the aerodigestive group had a higher resting heart rate, lower resting blood pressure, and lower baroreflex sensitivity than those in the digestive group.

The researchers will now look at the long-term impacts of throat conditions on autonomic health and the effects of treatment.