Carbonated soft drinks can cause heartburn

Carbonated soft drinks and one of the most commonly prescribed sleeping pills, benzodiazepines, can cause nighttime heartburn, according to new research.

A study published in the May issue of CHEST, the peer-reviewed journal of the American College of Chest Physicians, identifies these and other factors as causing reflux into the esophagus, so severe that it disrupts people's sleep on a regular basis.

"This is the first study to evaluate how common heartburn during sleep is in the general population of the United States," said the study's author, Ronnie Fass, MD, Southern Arizona VA Health Care System and University of Arizona College of Medicine, Tucson, AZ. "We found that up to a quarter of the US population loses sleep because of nighttime heartburn, and many of these individuals have related sleep complaints and suffer from excessive daytime sleepiness."

To determine predictive factors of heartburn during sleep, researchers from Tucson, AZ, Boston, MA, Baltimore, MD, and Minneapolis, MN, distributed self-report sleep habit questionnaires to 15,314 people from nine centers across the United States. The questionnaires asked whether the people suffered from heartburn during sleep, defined as "if they were awakened two or more times a month by heartburn." The questionnaires also gathered information on other patient demographics, sleep abnormalities, medical history and social habits. A total of 3,806 people (24.9%) reported experiencing heartburn during sleep. The results identify a link between carbonated soft drink consumption and nighttime heartburn, a result of the carbonated soft drinks' high acidity level. The study also showed that benzodiazepines were significantly associated with heartburn during sleep but did not find a similar connection for antidepressants or calcium channel blockers, two other types of medications known to precipitate gastroesophageal reflux. Other significant predictors of heartburn during sleep that were found include increased body mass index (BMI), various sleep abnormalities, hypertension, and asthma.

"Heartburn during sleep is indicative of nighttime reflux, which has been shown to be associated with a more severe form of gastroesophageal reflux disease," said Dr. Fass. "Inflammation of the esophagus, narrowing of the esophagus, and even cancer of the esophagus have been associated with nighttime reflux."

The study's findings also indicate that college graduates were significantly less likely to report heartburn during sleep than patients without a college education. This finding may reflect college graduates' greater understanding of the survey, or other factors, such as greater access to the healthcare system, more knowledge about the risk factors for heartburn, and improved diet and lifestyle.

"There are simple lifestyle changes people can make to help reduce their frequency of heartburn during sleep," said Paul A. Kvale, MD, FCCP, President of the American College of Chest Physicians. "Reducing consumption of carbonated soft drinks, replacing benzodiazepines with other types of sleeping pills, and losing weight can all help reduce nighttime heartburn."