If you’re plagued by throat issues, it could put you at a higher risk of suffering a potentially fatal “heart attack or stroke in the future,” according to fresh research. A recent study, published in JAMA Otolaryngology on September 5 of this year, revealed that individuals with throat problems had a reduced ability to control their blood pressure, leading to various issues. The University of Southampton spearheaded the research, suggesting that this occurs due to nerve damage in the throat affecting the baroreflex – a crucial component of the autonomic nervous system.
This is because this vital part of our bodies can detect shifts in blood pressure and when it does, it changes our heart rate and the tightness of our blood vessels to regulate our blood pressure, ensuing we don’t pass out when we stand up too quickly. This happens as your baroreceptors sense a lack of stretching of the artery walls and sends a message to your brain, which interprets it as insufficient blood pressure. Your brain then instructs your blood vessels to constrict in order to elevate your blood pressure.
However, when this happens, less energy is expended on controlling the baroreflex, meaning the body’s blood pressure and heart rate are poorly regulated. In fact, any alteration in your body’s demand for blood can activate your baroreceptor reflex. For instance, your body may need to adjust your blood pressure when you:
- Change your body position – including standing up
- See or experience something that frightens you
- Switch from walking to running
According to the new research by the University of Southampton and University Hospitals of Dorset Foundation Trust, the study suggests that the Vagus nerve, which is responsible for controlling the autonomic nervous system, prioritises airway protection over blood pressure regulation.
The lead author of the study, Reza Nouraei, who is a Professor of Laryngology and Clinical Informatics at the University of Southampton explains: “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.
“To compensate for a faulty throat, the autonomic control system must expend significant amounts of energy to maintain a safe airway. We found that in patients with a faulty throat, the heart, specifically a function called baroreflex, is less well controlled. This is one of the Peters that has been robbed to pay Paul.
“The problem with robbing this Peter is that it likely impacts long-term survival, as patients with reduced baroreflex function are more likely to die of a heart attack or stroke in years to come.”
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.
Reflux was a common cause of symptoms in both groups – making up the majority of digestive group cases with other causes like thinning of the vocal cord also present in the aerodigestive group. The team found 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.
Professor Nouraei revealed: “Now, and especially since Covid which damages nerves, we are seeing more patients with throat symptoms. Reduced baroreflex sensitivity impacts survival independent of other cardiovascular risks, so if the association we’ve discovered is confirmed by future studies, the need to make timely and accurate diagnoses and provide early and definitive treatments will become more pressing.”
The Vagus nerve, a crucial player in regulating blood pressure through the baroreflex, also oversees our heart rate, digestion, respiration, mood, and other vital functions that influence our health and wellbeing. Professor Nouraei highlighted the broader implications of the study, stating: “This study helps us to think about patients more holistically. As a clinician, if you can fix a problem in the throat that is potentially taking away bandwidth from the Vagus, then it frees up the nerve to give to the rest of the body.”
“If there is a chance that throat problems can affect functions like the baroreflex, or have a wider impact on overall wellbeing, then they need more consideration.”