Study: Asthma Drugs Do Not Stunt Growth
B O S T O N, Oct. 11, 2000 -- Parents of children with asthma may be able to breathe a little easier.
Two new studies report that stunted growth seen in asthmatic children who use corticosteroid inhalers — a commonly prescribed treatment — is temporary and probably disappears by adulthood. Both studies are in the Oct. 12 issue of the New England Journal of Medicine.
Previous research from the past decade found long-term use of this type of asthma medication can result in a 1 centimeter, or nearly a half an inch, loss of height in the first year of use. Such a finding left parents of children with mild asthma in a quandary about whether this side effect was worse than the ailment itself.
Asthma is the most common chronic respiratory childhood disease and is on the rise, affecting nearly 5 million U.S. children, according to the American Academy of Allergy, Asthma and Immunology. Childhood asthma results in 11 million missed school days and more than half a million trips to the emergency room annually.
Drugs Recommended, But Not Used
Corticosteroids (different than the performance-enhancing drugs athletes use) relieve asthma symptoms such as wheezing and coughing by reducing inflammation in the airways.
Although the National Heart, Lung and Blood Institute recommends either oral or nasally inhaled versions of corticosteroids as “the most effective long-term control medication for asthma,” a 1998 national survey on asthma found only one in five asthmatics had used either medication in the last month.
Doctors and parents have been reluctant to use corticosteroids, fearing that if this height loss continued each year, long-term use could stunt their child’s growth by as much as 4 to 6 centimeters, or 1 ½ to 2 ½ inches.
In 1998, the Food and Drug Administration made manufacturers of the drug place a label on all asthma corticosteroids informing users of this possible side effect. The agency also alerted doctors to monitor the growth of children using these medications.
“Parents are understandably cautious about treatments for their children that are in any way risky,” says Dr. Franklin Adkinson, a physician at the Johns Hopkins Allergy and Asthma Center in Baltimore and a lead author of one of the studies. “This study provides reassurance about the safety of this most effective class of asthma drugs — even in growing children.”
Study Tested Growth
In Adkinson’s study, a team of researchers from eight medical centers throughout the nation assigned more than 1,000 children ages 5 to 12 who had mild to moderate asthma to take either a placebo, a non-steroidal anti-inflammatory drug, or the corticosteroid budesonide (Pulmicort). Budesonide and beclomethasone dipropionate (Beclovent) are two of the inhaled corticosteroids researchers have linked to slower growth in children. The pharmaceutical companies provided the drugs.
After four to six years, the investigators found the corticosteroid was the most effective medication in reducing hospitalizations and asthma flare-ups — and only slowed growth by a centimeter during the first year.
The children had normal growth for the remaining time — but did end up 1.1 centimeters shorter than their peers by the end of the study. Using bone X-rays to measure wrist size, researchers, however, projected the children would eventually reach normal adult height.
The other study, from a team in Denmark, followed 211 children taking the same corticosteroid for an average of nine years through puberty. The group found the children grew to normal height.
Growth Returns to Normal
Some doctors hailed the two studies as reassuring news for parents and pediatricians.
“Medically, these are wonderful drugs for sick children with asthma, and there has been hesitancy to use them,” says Dr. Alan Leff, an asthma expert at the University of Chicago. “Steroid-phobia causes much more harm than good.”
But Dr. James Li, a professor of medicine at the Mayo Clinic in Rochester, Minn., who advised the FDA on its advisory label, says the slowed growth cautionary is still warranted. “Although the study is somewhat reassuring that the effect on growth is only 1 centimeter [the first] year, not 5 centimeters over five years,” he notes, “in some ways, it confirms the negative effects of corticosteroids.”
Experts are still unsure exactly why the steroids have this effect on the bones — or what effect the drugs might have on other developing internal organs.
Dr. Mary Ellen Wohl, chief of pulmonary medicine, and Dr. Joseph Majzoub, chief of endocrinology at the Children’s Hospital in Boston, wrote in an accompanying editorial that the drug should probably not been used on very young children because of its potential to affect certain growth. There also have been some concerns about high doses of the drug leading to cataracts in adults, although the study was inconclusive on this point.
Claude Lenfant, director of the the National Heart, Lung and Blood Institute, which funded the multi-center study, says the corticosteroids’ positive effects outweigh the slight impact on height.
“We recognize that even a slight slowing of growth may be a concern for parents,” he said in a statement. “But we believe this must be weighed against the benefits of improving the ability of a child with asthma to be active at play and school, to sleep through the night, and to stay away from the hospital.”