What do symptoms like chronic coughing, a sore throat, and hoarseness bring to mind? Many people experience these symptoms daily, yet they may not realize that they are associated with a reflux disorder called laryngopharyngeal reflux or LPR.
LPR has also been connected to other gastrointestinal conditions such as gastroesophageal reflux disease (GERD) and irritable bowel syndrome (IBS), as well as sleep apnea.
In this article, we’ll review what LPR is, common and uncommon symptoms associated with the condition, and what may cause LPR symptoms. Finally, we’ll review a few dietary approaches and treatment options that may help.
What Is LPR?
Laryngopharyngeal reflux (LPR) is a reflux condition that sometimes presents without heartburn or the noticeable pain that comes with acid reflux, therefore often making it difficult to identify until gradually worsening symptoms occur. This has earned LPR the nickname “silent reflux.”
Reflux occurs when the contents of your stomach backflow into your esophagus. When you have LPR, the contents of the stomach backflow all the way up into your larynx (the voice box) and your pharynx (your throat).
Normally, four barriers should keep the stomach contents from backing up into the throat:
The upper esophageal sphincter is the final barrier to your throat/pharynx. Except for when you’re swallowing food, liquids, or saliva, it should remain closed to protect the throat and keep stomach contents down. But it may become dysfunctional, causing the symptoms of LPR.
Common LPR Symptoms
Most LPR symptoms relate to the throat, including:
- Sore throat
- Chronic cough
- Chronic throat clearing
- Difficulty swallowing (dysphagia)
- Globus (feeling of a lump in your throat)
- Heartburn (may still occur, just less common).
Let’s expand on some of these symptoms and why you should pay attention to them:
- Hoarseness: An extremely common symptom of LPR. Hoarseness affects your voice, causing it to become breathy, low-pitched, or rough. Though it isn’t necessarily painful, hoarseness is a key indicator of dysfunction in the upper gastrointestinal tract, so be aware if it occurs.
- Dysphagia: Difficulty swallowing, also called dysphagia, can in serious cases lead to other issues, such as malnutrition, dehydration, unhealthy weight loss, and choking (though these are not common) [1, 2, 3].
- Chronic cough: A chronic cough without other common cold symptoms may be difficult to explain. However, LPR may be the cause. In a small study of 28 patients who complained of a chronic cough, researchers found that all 28 patients had symptoms consistent with LPR diagnosis. About 60% of patients were able to improve their symptoms through diet, lifestyle recommendations, and reflux medication .
- Heartburn and regurgitation: A burning sensation in your chest that may last anywhere from minutes to hours. Heartburn may also leave a bitter or sour taste in the back of your throat, a sign of regurgitation. Indigestion often accompanies heartburn. Though it’s less common than in GERD, those with LPR may experience heartburn. Almost 20% of the population in North America experiences heartburn at least once per week .
- Chronic throat clearing: Naturally, when reflux causes your stomach contents to rise back up into your throat, you may clear your throat. However, this just ends up causing further irritation and swelling to the vocal cords and throat. This may lead to a buildup of saliva, causing more throat clearing, and a vicious cycle begins.
- Globus (lump in throat): When you feel like there is a lump stuck in your throat. It often goes hand in hand with chronic throat clearing and coughing. LPR is the most common cause of this symptom .
What Causes LPR?
There has been a lot of research into the potential causes behind LPR symptoms. Here’s what we know.
Reflex Theory vs. Reflux Theory
Firstly, there are two different theories about the mechanisms of LPR: reflex theory vs. reflux theory.
Reflux theory is the more common explanation. Here, stomach contents back up all the way into the throat, causing irritation, hoarseness, etc.
Reflex theory states that regurgitation of stomach contents only occurs as far as the esophagus. From the esophagus, LPR symptoms are caused by stimulation of the vagus nerve. The vagus nerve is the longest of the 12 cranial nerves and controls actions like swallowing and coughing.
More specific contributors to LPR symptoms include the following:
- Sleep apnea: There is a significant connection between patients with sleep apnea and LPR symptoms. A systematic review and meta-analysis of 10 studies connected the two conditions, showing that of those with obstructive sleep apnea, almost half also had LPR (45.2%) . However, there was no difference in the frequency of sleep apnea occurrences between those with LPR and those without.
- Pepsin: The digestive enzyme pepsin may be involved in LPR symptoms. One study showed that 82% of LPR patients had pepsin in their saliva, when it should be concentrated in the stomach. But their pepsin levels weren’t associated with LPR symptoms . An additional review of 18 studies further explains that pepsin in reflux can exacerbate LPR symptoms .
- Poor esophageal motility: When muscle contractions that push food and liquid down the esophagus are weakened, potentially resulting in reflux symptoms .
- H. Pylori infection: A bacteria that normally resides in the stomach can overgrow and damage the stomach lining, cause inflammation, and instigate LPR [11, 12].
- Hiatal hernia: Occurs when the stomach pushes up through a small opening in the diaphragm, leading to pain and possible GERD or LPR symptoms .
Is GERD a Cause of LPR?
LPR and GERD are closely related, but their connection remains unclear.
A comprehensive literature review of 18 studies showed that LPR and GERD have several symptoms in common, and that at least 50% of LPR patients have GERD.
Research does show that if GERD is left untreated, it can turn into LPR, but it’s unclear whether GERD directly causes LPR symptoms to develop .
Here’s a comparison of common and less common LPR and GERD symptoms:
The Connection Between LPR and Gut Health
There is also a strong connection between LPR and gut health more generally. For example, reflux is a common symptom of irritable bowel syndrome (IBS), and it may also be connected to small intestinal bacterial overgrowth (SIBO).
A large study found that many symptoms overlapped between GERD and IBS . LPR, GERD, IBS, and depression were also linked in another large study, suggesting there may be a common root cause in the gut underlying all of these conditions .
If IBS and LPR share a root gastrointestinal cause, finding that common root cause and healing it may address the symptoms of both conditions.
This connection also suggests that therapeutic diets like the low FODMAP diet, which has been shown to be helpful in cases of IBS, may be effective at treating LPR symptoms, too.
Possible Complications of LPR
In rare cases, if left untreated, LPR can lead to long-term consequences like vocal injury or scarring of the vocal cords. Conditions like emphysema, bronchitis, or asthma can also be aggravated by LPR. Other possible complications include:
- Airway reflux and chronic obstructive pulmonary disease (COPD): Two studies connected LPR to airway reflux and COPD [19, 20].
- Chronic respiratory conditions: An analysis of 113 asthma clinic patients found that LPR appears to cause chronic respiratory symptoms .
- Subglottic stenosis: This is a narrowing of the airway immediately below the vocal cords, which LPR can cause in rare cases. Typical signs of subglottic stenosis include noisy breathing or difficulty breathing .
- Cancer of the larynx: LPR has been connected to cancer of the larynx by multiple research studies, but its relationship remains unclear due to the potential roles of alcohol and tobacco use and reflux misdiagnosis [23, 24, 25].
Because of varying causes and symptoms, there isn’t a single standard treatment for LPR. But there are many options available to reduce symptoms, including diet and lifestyle changes.
Lots of research has investigated the connections between certain food and beverages and LPR symptoms. Though some foods may be clear LPR triggers for some people, the ideal diet for LPR will be different for each individual. Problematic foods can be identified with an elimination diet and later reintroduced once you’ve had some time to heal.
We usually recommend most people start with the Paleo diet for identifying trigger foods, reducing inflammation, and beginning to heal the gut .
It’s also helpful to be mindful of the common foods that trigger LPR symptoms:
If diet alone isn’t enough, the next step is to investigate potential gut imbalances that could cause LPR symptoms.
Small bacterial intestinal overgrowth (SIBO) is one possible cause, though there is no definitive research connecting the two conditions yet. SIBO produces gas that can lead to excessive burping, belching, and other common reflux symptoms . SIBO can also change how much stomach acid you produce, which contributes to reflux [30, 31].
Probiotics may be a good therapy for LPR treatment. Multiple studies have shown that probiotics are effective in treating GERD symptoms .
Conventional treatment options for the treatment of LPR may include medications such as:
- H2 blockers (antihistamines)
- Proton pump inhibitors (PPIs) such as omeprazole or esomeprazole.
Sometimes, a procedure called fundoplication is recommended. In this surgical procedure, part of the stomach is wrapped around the esophagus to keep stomach contents from refluxing.
Get to the Bottom of LPR Symptoms
LPR is a condition that can be addressed naturally through a combination of diet, lifestyle, and therapeutic supplements when necessary. If you’ve been consistently experiencing LPR symptoms such as chronic cough, sore throat, or difficulty swallowing, reach out to us at the Ruscio Institute for Functional Medicine to get started on a personalized diet and treatment plan.