TUESDAY, Jan. 24 (HealthDay News) -- Children with asthma who don't have heartburn and other signs of gastroesophageal reflux don't get additional asthma control from acid-reducing medications, according to new research.

And, taking these medications when there are no digestive issues increases a child's risk of developing a respiratory infection, reports the study.

"There's a strong epidemiological link between acid reflux and asthma," explained study co-author Janet Holbrook, an associate professor of epidemiology at the Johns Hopkins Bloomberg School of Public Health in Baltimore. As a result, current asthma guidelines call for evaluating people with asthma for acid reflux, Holbrook said.

Because definitive tests for excess acid production can cause children discomfort, some doctors may choose to do a trial of acid-suppressing medications called proton pump inhibitors (PPIs). Some common brand names in this class of medication are Prilosec, Prevacid and Nexium.

"Our findings suggest that physicians should not take kids with poorly controlled asthma and test whether PPIs will help," said Holbrook.

Results of the study are published in the Jan. 25 issue of the Journal of the American Medical Association. The study was funded by the U.S. National Institutes of Health and conducted by the American Lung Association Asthma Clinical Research Centers.

Asthma and gastroesophageal reflux (GER or GERD) are common conditions in children. Youngsters with asthma often have symptoms of gastroesophageal reflux. In adults, PPIs seem to help people with asthma who also have symptoms of gastroesophageal reflux, but not those who don't have symptoms, such as frequent heartburn.

The current study included 306 children recruited from 19 centers across the United States between 2007 and 2010. The average age was 11 years. All had poor asthma control despite receiving treatment with inhaled corticosteroids.

The children were randomly assigned to receive either lansoprazole -- a PPI -- or a placebo daily for six months. The dose of lansoprazole was based on the child's weight.

Asthma improvement was assessed through a change in the Asthma Control Questionnaire, which has a scale of 0 to 6. A change of 0.5 is considered clinically significant. Lung function was also measured.

After six months, there were no statistically significant differences between the groups. The average change in the Asthma Control Questionnaire score was only 0.2, and there were no statistically significant changes in lung function, quality of life or rate of asthma flare-ups.

In addition, among 115 children who also had a 24-hour esophageal acid study, 43 percent were found to have elevated levels of acid production. Yet even in this group, treatment with lansoprazole didn't improve asthma symptoms over placebo.

Holbrook said although this study only looked at one PPI, she believes the results would hold true for other medications in this class of drugs.

Children taking lansoprazole had about a 30 percent higher risk of respiratory infections and sore throats in this study. PPIs were also associated with a difference in the risk of activity-related bone fractures, although the difference was not statistically significant, according to an accompanying editorial in the same issue of the journal.

"PPIs do not improve asthma in children who do not have symptoms of GER/GERD, and it is unlikely to be of great benefit even in children who do have such symptoms," said the editorial author, Dr. Fernando Martinez, director of the Arizona Respiratory Center at the University of Arizona in Tucson.

"The substantial increase in use of PPIs in children during the last decade is worrisome and unwarranted," he wrote.

Still, Martinez advised parents not to abruptly discontinue any medications. Parents "should consult their pediatricians, who can best evaluate the clinical situation for each child," he said.

Holbrook agreed and said if a child is on a PPI, it's reasonable for parents to ask why. She noted that these medications may come with an additional risk and cost, and they may not have any additional benefit.

"If your child is on a PPI for asthma, it's not an effective treatment. These medications are approved for the treatment of acid reflux," said Holbrook.

More information

Learn more about asthma treatment from the U.S. National Heart, Lung, and Blood Institute.

FRIDAY, Jan. 20 (HealthDay News) -- A new study found no statistically significant link between asthma medication use during pregnancy and common birth defects.

However, the study did find a positive association between some rare birth defects and mothers with asthma, and potentially with their medication use. But, the researchers couldn't tease out whether the problem was a loss of oxygen from less than well-controlled asthma or an effect of medications.

"Worsening asthma is a risk to the mom and the fetus. Hypoxia (a lack of oxygen) we know is a problem for a developing fetus. And, the potential risk they found here is very small. Even if it turns out to be a true increase, the risk is so small. This study raises more questions than it answers," said Dr. Natalie Meirowitz, chief of the division of maternal fetal medicine at Long Island Jewish Medical Center in New Hyde Park, N.Y.

What's most important, she said, is that expectant mothers with asthma don't just stop their medications. "That's really a problem, and then they end up needing more medication," she said.

Findings from the study were published online Jan. 16, ahead of February print publication in Pediatrics.

Between 4 percent and 12 percent of expectant mothers have asthma, according to background information in the article. Current guidelines recommend that women keep taking their asthma medications during pregnancy.

There are two main types of asthma medications: bronchodilators (also known as rescue medication) and anti-inflammatories, which include inhaled and oral steroids, as well as several other medications. Anti-inflammatory medications are generally used long term to help control asthma symptoms.

For the study, the researchers compared nearly 2,900 infants born with birth defects to more than 6,700 babies born with no birth defects. Mothers of these infants were asked to recall their medication use one month before and during pregnancy.

For most birth defects, the researchers found no statistically significant associations between asthma medication use and the development of birth defects.

They did, however, find a positive association between asthma medication use and certain rare birth defects. The risk of isolated esophageal atresia -- an abnormality of the esophagus -- was more than doubled in women who used bronchodilators. The risk of isolated anorectal atresia -- a malformed anus -- was more than doubled with maternal anti-inflammatory use. And, the risk of omphalocele -- a defect in the abdominal wall -- was more than quadrupled for either type of asthma medication.

But, the authors wrote, the "observed associations may be chance findings or may be the result of maternal asthma severity and related hypoxia rather than the medication use."

They added that it's also important to keep these findings in context. The rate of these birth defects ranged from 1.2 to 4.6 per 10,000 births. So, even a four-fold increase in the risk of having one of these defects results in far less than a 1 percent chance for any individual woman and her child.

"As obstetricians, we need to pay attention to this, but it's really important to oxygenate mom. We really need to make sure that there's oxygen flowing freely between mom and baby," said Dr. Mary Rosser, an obstetrician with Montefiore Medical Center in New York City.

Also, Rosser pointed out that there was a lot that wasn't known about the expectant mothers. The authors weren't able to assess the severity of their asthma. They also didn't know anything about the medication doses.

Asthma expert Dr. Jennifer Appleyard agreed with Rosser and Meirowitz. "They really couldn't tease apart what was the medicine and what was the asthma," she said.

"You need to treat the asthma. There's more risk to uncontrolled asthma than a slight possible risk of a rare birth defect," said Appleyard, the chief of allergy and immunology at St. John Hospital and Medical Center in Detroit.

"No matter what type of patient you're treating -- expectant mom or not -- the goal is to treat patients with the minimum amount of medication necessary," she added.

Rosser and Meirowitz said that, ideally, women should visit their obstetrician/gynecologist before getting pregnant to review their medication use and to make sure that their asthma is well controlled.

More information

Learn more about asthma during pregnancy from the American College of Allergy, Asthma and Immunology  .