Cutting back on carbonated soft drinks may help heartburn sufferers sleep more soundly, a study published Monday suggests.

Among more than 15,000 U.S. adults surveyed on Heartburn symptoms, researchers found that drinking soda, taking benzodiazepine-type sleeping pills, and being overweight were all associated with an increased risk of nighttime heartburn woes.

Men and women with high blood pressure or Asthma were also at greater risk of overnight symptoms, the study found.

Heartburn refers to the fiery sensation in the chest caused by stomach acids backing up into the esophagus. Frequent bouts of heartburn may be indicative of Gastroesophageal Reflux Disease, or GERD, a disorder in which the muscular valve between the esophagus and stomach fails to close properly, allowing acids to back up into the throat.

GERD can cause corrosive changes in the esophagus that make swallowing difficult, or that in some cases lead to Barrett’s esophagus, where cells in the esophageal lining become abnormal. In a small number of people, Barrett’s esophagus precedes the development of esophageal cancer.

It’s thought that nighttime acid reflux, in particular, may be a sign of more severe GERD - making it important to uncover the risk factors for nighttime symptoms, said Dr. Ronnie Fass, the study’s lead author.

Fass, who is with the University of Arizona College of Medicine and the Southern Arizona VA Health Care System in Tucson, said that his team’s findings point to several potential ways to prevent heartburn during sleep.

“Avoid carbonated beverages, in particular with dinner,” he advised. “And definitely don’t have them after dinner.”

For Heartburn sufferers, the problem with soft drinks is their high acid content - higher even than that of coffee, according to Fass. On top of that, the carbonation that makes soda bubbly introduces carbon dioxide into the stomach, worsening the situation for the heartburn-prone.

In their study, Fass and his colleagues found that of 15,314 older men and women surveyed, one-quarter said they had nighttime heartburn symptoms. Besides soda drinking, several other risk factors for the problem emerged.

One was the use of benzodiazepines, a class of sedatives commonly used for insomnia. Research has shown that the drugs can lower the pressure of the sphincter that opens and closes the passageway from the esophagus to the stomach, Fass and his colleagues note in the report.

Why the medications would spur nighttime symptoms, in particular, is not clear. Still, Fass said, “I would recommend that people who suffer from this avoid benzodiazepines.”

The researchers also found that people with high blood pressure or asthma were at greater risk of heartburn during sleep. Regarding the high blood pressure finding, Fass said the disease itself probably does not trigger heartburn; instead, the blame may lie with high blood pressure medications, or with other factors that often accompany high blood pressure - such as excess weight.

In contrast, although asthma medications can have the side effect of heartburn, the disease itself may sometimes lead to acid reflux, Fass said. Asthma may trigger heartburn by increasing pressure between the chest and abdomen.

Higher body mass index (BMI), a measure of weight in relation to height, was also tied to a greater risk of nighttime heartburn - not surprisingly, the researchers note, given the known association between excess pounds and GERD.

That, Fass said, makes weight loss another possible way to prevent nighttime acid reflux.

SOURCE: Chest, May 2005.