Patients experiencing throat issues have demonstrated a diminished ability to manage their blood pressure, according to a recent study conducted by the University of Southampton. This research highlights a decrease in baroreflex sensitivity among patients exhibiting throat symptoms.
Patients experiencing throat issues have shown less ability to manage their blood pressure in a recent study from the University of Southampton.
The study, published in JAMA Otolaryngology, is the first to identify reduced baroreflex sensitivity in individuals with throat-related symptoms.
The baroreflex is an essential function of the autonomic nervous system, which monitors variations in blood pressure and adjusts heart rate and the tone of blood vessels to keep blood pressure stable. This reflex is crucial for preventing fainting when a person stands up.
The research team from the University of Southampton and University Hospitals of Dorset Foundation Trust posits that the findings might be due to the Vagus nerve—which oversees the autonomic nervous system—prioritizing airway protection over less critical tasks like regulating blood pressure.
“Our immediate survival relies on the throat effectively managing the separation of air and food passages each time we swallow,” explains the lead author of the study, Reza Nouraei, Professor of Laryngology and Clinical Informatics at the University of Southampton.
“The throat accomplishes this via sensitive reflexes; however, when these reflexes are disrupted, such as by a viral infection like Covid or reflux that impacts the nerves in this area, control over this vital junction deteriorates, leading to symptoms like a sensation of a lump in the throat, persistent throat clearing, and coughing.
“To counteract an impaired throat, the autonomic control system requires substantial energy to ensure a safe airway. Our findings suggest that in patients with a compromised throat, heart control, particularly baroreflex function, is diminished. This is akin to ‘robbing Peter to pay Paul.’
“The concern with this ‘robbing’ is that it may affect long-term survival, as those with diminished baroreflex ability may face a higher risk of dying from a heart attack or stroke in later years.”
The researchers examined heart rates, blood pressure, and baroreflex sensitivity in 23 patients who had undergone Ear, Nose, and Throat (ENT) surgery with aerodigestive (laryngopharyngeal) symptoms, compared to 30 patients with digestive (esophagogastric) symptoms admitted to Gastroenterology at University Hospitals of Dorset NHS Foundation Trust.
Reflux was commonly identified as a source of symptoms in both groups, accounting for most cases in the digestive group. Other factors, such as vocal cord thinning, were noted in the aerodigestive group.
Results indicated that patients in the aerodigestive category exhibited a higher resting heart rate, lower resting blood pressure, and reduced baroreflex sensitivity compared to those in the digestive group.
“Currently, and particularly since the onset of Covid—which impacts nerves—we are observing an increase in patients with throat symptoms,” stated Professor Nouraei.
“The reduced baroreflex sensitivity affects the likelihood of survival, independent of other cardiovascular factors. Therefore, if future studies validate our findings, it will highlight the urgent need for timely and accurate diagnoses and effective treatments.”
This study adds to the growing interest in the Vagus nerve and overall health. Besides blood pressure regulation via the baroreflex, the Vagus nerve influences heart rate, digestion, breathing, mood, and numerous other vital functions affecting overall well-being.
Professor Nouraei remarks: “This research encourages us to consider patients more comprehensively. As a clinician, addressing a throat issue that may be draining resources from the Vagus can improve functioning throughout the body.”
“If throat problems potentially impact functions like the baroreflex or broader well-being, they merit deeper evaluation.”
The research team will further investigate the long-term effects of throat conditions on autonomic health and the implications of various treatments.
Baroreflex Sensitivity in Patients With Laryngopharyngeal Dysfunction — The Overwhelmed Vagus Hypothesis has been published in JAMA Otolaryngology and is accessible online.
This research received support from the Robert White Legacy Fund.
