Functional heartburn describes a persistent burning sensation behind the breastbone, similar to typical acid reflux. This condition is distinct because it is not caused by abnormal acid reflux or any observable structural problems within the esophagus. Despite the absence of physical damage or excessive acid, the symptoms are real and can be frustrating for individuals.
Distinguishing Functional Heartburn from GERD
Gastroesophageal Reflux Disease (GERD) involves the abnormal backflow of stomach acid into the esophagus, often due to a weakened lower esophageal sphincter. This reflux can lead to visible inflammation or damage to the esophageal lining, known as esophagitis. Symptoms of GERD typically improve with acid-reducing medications like proton pump inhibitors (PPIs).
Functional heartburn, in contrast, presents with similar burning sensations. It is characterized by a heightened sensitivity of the esophagus to normal levels of acid or even non-acidic stimuli, such as food passing through. People with functional heartburn often find that standard acid-blocking treatments do not alleviate their symptoms effectively.
The Underlying Causes of Hypersensitivity
One significant aspect of esophageal hypersensitivity in functional heartburn is visceral hypersensitivity. Here, nerves in the esophagus become overly sensitive, causing even normal physiological events to be perceived as painful, meaning individuals have a lower pain threshold.
Another contributing factor is altered brain-gut interactions, the communication pathway between the central nervous system and the digestive system. This can lead to the brain misinterpreting normal signals from the esophagus as discomfort or pain, amplifying sensations that would otherwise go unnoticed.
Psychological factors, including stress, anxiety, and depression, also play a role in amplifying pain signals and exacerbating symptoms in functional gastrointestinal disorders. These emotional states can influence the gut-brain axis, potentially increasing pain perception and leading to changes in esophageal permeability. While not direct causes, these factors can significantly impact symptom severity.
The Path to a Diagnosis
Diagnosing functional heartburn is a process of exclusion, requiring other potential causes for symptoms to be ruled out. This evaluation ensures the burning sensation is not due to acid reflux, structural issues, or other gastrointestinal disorders. The diagnostic journey typically begins with a detailed medical history and physical examination.
An upper endoscopy is commonly performed to visually inspect the esophagus, stomach, and the first part of the small intestine. This procedure checks for inflammation, erosions, ulcers, or structural abnormalities. In functional heartburn cases, endoscopy results usually appear normal.
Esophageal pH monitoring, often conducted over 24 to 96 hours, measures acid exposure in the esophagus. This test uses a small probe or wireless capsule to record pH levels. For a functional heartburn diagnosis, the test typically shows normal acid levels, with no consistent correlation between acid reflux events and reported heartburn symptoms.
The formal diagnosis of functional heartburn is based on the Rome IV criteria for functional gastrointestinal disorders. These criteria specify that individuals must experience burning retrosternal discomfort or pain at least twice a week for the past three months, with symptom onset occurring at least six months prior to diagnosis. Additionally, there must be no symptom relief despite optimal antisecretory therapy, and no evidence of GERD, eosinophilic esophagitis, or major esophageal motor disorders.
Approaches to Managing Symptoms
Managing functional heartburn symptoms often involves strategies tailored to address nerve hypersensitivity rather than acid reduction. Medical interventions frequently include neuromodulators, such as low-dose tricyclic antidepressants (TCAs) or selective serotonin reuptake inhibitors (SSRIs). These medications work by calming overactive nerve endings and reducing visceral hypersensitivity, rather than acting as mood stabilizers at these lower doses.
Psychological and behavioral therapies also play a significant role in symptom management. Cognitive Behavioral Therapy (CBT) helps individuals identify and modify thought patterns and behaviors related to their symptoms, reducing hypervigilance and improving coping mechanisms. Hypnotherapy, specifically gut-directed hypnotherapy, can modulate the visceral sensory pathways and reduce pain sensitivity, with some studies indicating benefits for symptom relief and quality of life.
Mindfulness-based approaches teach individuals to observe their symptoms in a non-judgmental way, which can reduce the distress associated with chronic pain and decrease visceral hypersensitivity. These therapies aim to enhance the brain’s ability to process and respond to signals from the gut differently. Stress management techniques are also important, as stress can exacerbate symptoms.
Lifestyle and dietary adjustments can further support symptom management. Eating smaller, more frequent meals and avoiding large meals, particularly close to bedtime, can help reduce pressure on the digestive system. Elevating the head of the bed by 6 to 9 inches can prevent stomach contents from refluxing while lying down, and wearing loose-fitting clothing avoids abdominal compression. While diet is not a direct cause, some individuals find it helpful to identify and avoid specific foods that personally irritate their symptoms.