What causes reflux at night
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Causes of Nighttime Reflux: An Overview
Physiological Changes During Sleep and Nighttime Reflux
Reduced Saliva Production and Swallowing Frequency
One of the primary causes of nighttime gastroesophageal reflux disease (GERD) is the physiological changes that occur during sleep. These changes include a significant reduction in saliva production and swallowing frequency, which are crucial for neutralizing and clearing acid from the esophagus. The decreased saliva and swallowing lead to prolonged esophageal acid clearance and increased acid-mucosal contact time during sleep, making reflux events longer and more severe compared to daytime reflux1 3 4.
Decreased Conscious Perception and Arousal
During sleep, there is a decreased conscious perception of heartburn, which means individuals are less likely to wake up and perform behaviors that would help clear the acid, such as swallowing or changing positions. This lack of arousal and subsequent clearance behaviors further exacerbates the duration and impact of reflux events during the night1 4.
Slower Gastric Emptying
Another contributing factor is slower gastric emptying during sleep. This delay in the stomach's ability to process and move food into the intestines can increase the likelihood of reflux, as the stomach remains fuller for longer periods, creating more pressure that can push stomach contents back into the esophagus1 4.
Sleep Disorders and GERD
Obstructive Sleep Apnea (OSA)
Obstructive sleep apnea (OSA) is a condition that has been linked to an increased risk of nocturnal GERD. OSA causes repeated interruptions in breathing during sleep, which can lead to changes in intrathoracic pressure and promote reflux. The presence of OSA can help identify patients who are more likely to experience nighttime GERD symptoms1 3 4.
Sleep Deprivation
Sleep deprivation itself has been shown to enhance the perception of intraesophageal acid, making GERD symptoms more severe. Patients with GERD who experience sleep deprivation report increased symptom intensity and sensitivity to acid perfusion, which suggests that lack of sleep can exacerbate the condition2 4.
Lifestyle Factors and Nighttime Reflux
Late Night Meals
Consuming meals late at night is a significant lifestyle factor that can contribute to nighttime reflux. Eating close to bedtime increases the likelihood of reflux as the body is in a recumbent position, which makes it easier for stomach contents to flow back into the esophagus. Avoiding late-night meals is recommended as a preventive measure for nighttime GERD4 6.
Napping
Interestingly, napping has been associated with more frequent and severe reflux events compared to nocturnal sleep. Studies have shown that naps, especially those taken after meals, can lead to a higher number of reflux events and longer acid exposure times, suggesting that the timing and context of sleep can influence GERD severity8.
GERD and Sleep Disturbances
Bidirectional Relationship
The relationship between GERD and sleep disturbances is bidirectional. GERD can cause sleep disruptions due to nighttime heartburn and arousals, while poor sleep quality and sleep deprivation can worsen GERD symptoms. This interplay highlights the importance of addressing both GERD and sleep issues in affected patients2 4 6.
Treatment Approaches
Effective management of nighttime GERD often involves lifestyle modifications, such as avoiding late-night meals and elevating the head of the bed. Medical treatments, including proton pump inhibitors (PPIs) and H2 receptor antagonists, have been shown to alleviate nocturnal heartburn and improve sleep quality, although their effects on objective sleep parameters remain unclear4 6.
Conclusion
Nighttime reflux is influenced by a combination of physiological changes during sleep, sleep disorders, lifestyle factors, and the bidirectional relationship between GERD and sleep disturbances. Understanding these factors is crucial for effective management and improving the quality of life for individuals suffering from nocturnal GERD. Addressing both the reflux and sleep components through lifestyle changes and medical treatments can help mitigate the impact of nighttime GERD.
Sources and full results
Most relevant research papers on this topic
Review article: sleep and its relationship to gastro‐oesophageal reflux
Night-time GERD events are less frequent but significantly longer, due to physiological changes and increased risk of serious complications.
Literature Review
Highly CitedSleep deprivation is hyperalgesic in patients with gastroesophageal reflux disease.
Sleep deprivation increases the perception of esophageal acid in patients with gastroesophageal reflux disease, potentially increasing symptom severity.
RCTHighly CitedGastroesophageal reflux disease and sleep disturbances
GERD is associated with sleep disturbances, and lifestyle modifications and proton pump inhibitors can improve nighttime symptoms and quality of life.
Rigorous JournalHighly CitedReview article: supra‐oesophageal manifestations of gastro‐oesophageal reflux disease and the role of night‐time gastro‐oesophageal reflux
Night-time gastroesophageal reflux contributes to supra-oesophageal symptoms like asthma and idiopathic pulmonary fibrosis, and should be considered when diagnosing and treating GERD-related supra-oesophageal symptoms.
Literature ReviewHighly CitedA systematic review of the definitions, prevalence, and response to treatment of nocturnal gastroesophageal reflux disease.
Nocturnal GERD is common and associated with poor sleep quality, but can be effectively managed with medical and surgical therapies.
Systematic ReviewHighly CitedGastro-oesophageal reflux and nocturnal asthma.
Gastro-oesophageal reflux at night is not a strong or immediate trigger for nocturnal asthma, but it does influence bronchial obstruction during the night, as demonstrated by low morning peak expiratory flow values.
Observational StudyNaps are associated more commonly with gastroesophageal reflux, compared with nocturnal sleep.
Naps are associated with significantly greater numbers and duration of esophageal acid exposure and symptoms compared to nocturnal sleep, potentially impacting disease severity in patients with GERD.
Observational StudyAmbulatory pH monitoring of gastro-oesophageal reflux in "morning dipper" asthmatics.
Morning dipping in asthmatics is not associated with gastro-oesophageal reflux, and a randomized, double-blind trial of ranitidine versus placebo showed no significant difference in peak expiratory flow rates or patient well-being.
RCTHighly CitedTemporal Relationship Between Night-Time Gastroesophageal Reflux Events and Arousals From Sleep.
Night-time gastroesophageal reflux (nGER) does not cause arousal from sleep, but rather arousal from sleep predisposes to nGER events.
Observational Study