WEDNESDAY, Feb. 27 (HealthDay News) -- The incidence of cystic fibrosis may be decreasing, and a more severe form of the disease caused by one particular gene also appears to be on the decline.

Those are the two main findings from a Massachusetts study that found the overall incidence of cystic fibrosis dropped from between 25 and 35 babies a year before 2003 to less than 20 babies each year for most years after 2003.

The study also found that the incidence of a severe form of the disease, caused by the genotype ΔF508/ΔF508, also dropped dramatically. Before 2003, at least 10 babies were born with this form of cystic fibrosis each year. In 2003 and beyond, only about five babies were born annually with this type of cystic fibrosis in the Massachusetts area, according to the study.

"The most severe genotype has dropped out dramatically. The new mix has some severe genotype, but overall, it's a milder group of kids, though not everyone has mild disease," said one of the study's authors, Anne Marie Comeau, deputy director of the New England Newborn Screening Program in Jamaica Plain, and an associate professor of pediatrics at the University of Massachusetts Medical School in Worcester.

The findings were published as a letter in the Feb. 28 issue of the New England Journal of Medicine.

Cystic fibrosis is an inherited disorder that affects mucus production and the sweat glands, making mucus sticky and thick, and sweat becomes extremely salty. The disorder affects many major organs, such as the lungs, pancreas and intestines. Mucus can clog the lungs, causing breathing problems and making it easy for bacteria to grow, leading to lung infections and lung damage.

While there's no cure for cystic fibrosis, treatments have improved greatly in recent years. Until the 1980s, most deaths from the disorder occurred in children and teens. Today, people live, on average, to be more than 35 years old, according to the U.S. National Library of Medicine.

Both parents must be carriers of a cystic fibrosis gene for a child to be born with the disorder. However, carriers have no symptoms and often have no idea that they carry the cystic fibrosis gene. Even when both parents carry a cystic fibrosis gene, the chances are only one in four that a child will be born with the disorder, according to the U.S. National Heart, Lung, and Blood Institute (NHLBI).

About 30,000 Americans have cystic fibrosis, and it's most common in white people of Northern European descent, although people from all races can be born with cystic fibrosis, according to NHLBI.

The new research included data from the New England Newborn Screening Program and the Massachusetts Cystic Fibrosis Newborn Screening Work Group.

Comeau said the researchers believe that the decrease in the incidence of the ΔF508/ΔF508 type, as well as other forms of cystic fibrosis, owes to prenatal screening to see if parents are carriers of a cystic fibrosis gene.

She said the most important implication of this research, however, is for people evaluating treatments for cystic fibrosis. She said it's very important for such researchers to know that "the cohort of children may be changing. If you test a treatment on kids inherently bound to have a less severe disease, you have to be careful when applying those findings to all kids," Comeau said.

Dr. David Orenstein, director of the Antonio J. and Janet Palumbo Cystic Fibrosis Center at Children's Hospital of Pittsburgh, said, "This study raises an interesting possibility. There have been some other geographic areas where this same trend toward lower birth rates or fewer children born with cystic fibrosis has been observed, and so it's possible that it's real. But, these things do go up and down a bit naturally."

Orenstein said he'd have liked to have seen the data broken down by ethnic groups, since the disease is more prevalent in people of Northern European descent. But, he also pointed out that the numbers of children included in this study were very small, which means the findings need to be confirmed.

More information

To learn more about cystic fibrosis and available genetic tests, visit the March of Dimes.

"Despite public health warnings, including a recent U.S. surgeon general's report stating that there is no risk-free level of secondhand smoke exposure, substantial numbers of individuals with CF are exposed to secondhand smoke. Unfortunately, published studies have been inconsistent in associating poorer clinical outcomes in patients with CF with secondhand smoke exposure," the Johns Hopkins University researchers wrote.

The researchers looked at several areas involving secondhand smoke and CF, a fatal disorder that affects more than 30,000 people in the United States. They analyzed data on hundreds of CF patients, and found that secondhand smoke exposure was associated with decreases in all measures of lung function studied. Socioeconomic status did not worsen the relationship between secondhand smoke and reduced lung function.

The researchers also found that certain mutations in the CF-causing gene (CFTR) determine the degree of effect that secondhand smoke has on lung function in CF patients.

The study is published in the Jan. 30 issue of the Journal of the American Medical Association.

"CF may be a good model for uncovering gene-environment interactions that are detrimental to lung function. This study also raises the specter that healthy children bearing certain genetic variants may be at much higher risk for worse outcomes as a result of secondhand smoke exposure," the study authors wrote.

"Demonstration that genetically defined subsets of patients with CF exposed to secondhand smoke in the home have a substantial lifetime reduction in lung function provides potent justification for eradication of cigarette smoke exposure for all individuals with this life-limiting disorder," they concluded.

More information

The March of Dimes has more about cystic fibrosis.

A team at Case Western Reserve University School of Medicine, in Cleveland, found that children with cystic fibrosis who took high doses of ibuprofen twice a day had a 29 percent reduction in loss of lung function compared with children who did not take the drug.

"In cystic fibrosis the lungs are destroyed by chronic infection and inflammation. One of the treatments for that would be anti-inflammatory therapy," explained lead researcher Dr. Michael W. Konstan, director of the Cystic Fibrosis Center at Rainbow Babies and Children's Hospital.

One expert agreed that ibuprofen should be more widely used in treating the illness.

"This study confirms the benefit of ibuprofen in children with cystic fibrosis," said Dr. Bruce Marshall, vice president of clinical affairs at the Cystic Fibrosis Foundation.

In fact, the foundation currently recommends ibuprofen therapy. "This paper is in alignment with Cystic Fibrosis Pulmonary Guideline Committee recommendations," Marshall said.

CF is a genetic disease that affects the lungs and other organs. It's characterized by thick, sticky mucus that makes it almost impossible for CF patients to fight off germs and infections. The disease is always fatal, and lung disease accounts for 85 percent of deaths among CF patients. However, advances in treatment in the last 60 years have increased life expectancy from just a few years to about 36 years.

A decade ago, Konstan had shown that daily use of ibuprofen could slow the progression of the disease. "Our hope was that that would translate into increased years of survival," he said.

Since that time ibuprofen therapy has not been used very much, Konstan noted. "Only about 5 percent of patients who are eligible for this therapy are actually treated with ibuprofen," he said.

Part of the reluctance to use ibuprofen is the fear on the part of doctors of increased gastrointestinal bleeding, a common side effect with ibuprofen and other anti-inflammatory drugs, Konstan explained.

But he added that this problem "happens in about one in 500 treated patients. That's an awfully small risk considering the strong benefit."

In the new study, which appears in the December issue of American Journal of Respiratory and Critical Care Medicine, Konstan's team was able to show that the risk of gastrointestinal bleeding was small while the benefit was significant.

Konstan's group looked at 1,365 children who took ibuprofen and 8,960 who did not. Patients ranged from 6 to 17 years of age. Doses ranged from 20 milligrams to 30 milligrams per kilogram of the patient's weight. Some patients took up to 1,600 milligrams per dose -- typical, over-the-counter doses of ibuprofen recommend a maximum dose of 1,200 milligrams for people over 12 years of age.

The researchers found that for patients taking ibuprofen, the progression of the disease was cut by almost one-third compared with those not taking the drug. Moreover, gastrointestinal bleeding was rare, with an incidence of 0.37 percent in children taking ibuprofen, compared with 0.14 percent in those not taking the drug.

"Based on these findings, we should reconsider the use of ibuprofen as a treatment option," Konstan said. Whether ibuprofen actually increases survival isn't known, but based on the slowing of the disease, Konstan thinks that it probably does.

The researcher noted that his team has been looking for an anti-inflammatory alternative to ibuprofen for 10 years, but they have yet to find one that is as effective and safe as the common drug. "We continue to search for alternatives to ibuprofen," Konstan said.

More information

For more information on cystic fibrosis, visit the Cystic Fibrosis Foundation.

It is a controversial conclusion, made more controversial because the transplant rules have been changed since the study was done, said Dr. Theodore G. Liou, associate professor of internal medicine at the University of Utah, and lead author of a report in the Nov. 22 New England Journal of Medicine.

CF is a hereditary disease in which the lungs and digestive tract become clogged with mucus. People with CF die at a relatively young age. Previous studies have shown some survival benefit for adult cystic fibrosis sufferers who received lung transplants as a last resort, Liou said.

The new report is one of very few looking at such transplants in children, he said. "In 2005, we published one [study] showing no difference in outcome between patients who were transplanted and those who were not, although they were equally sick as far as we could tell," Liou said. "That got us into a lot of trouble, because people didn't like the results."

The new study looked at 514 children with cystic fibrosis who were on the waiting list for lung transplants from 1992 to 2002. A total of 248 of the children did undergo the procedure during the study period.

The researchers found a significant estimated benefit for only five of those who had transplants, with "a significant risk of harm" associated with lung transplantation for 315 of the young patients, meaning that other treatment would have benefited them more.

The process has changed since the study was conducted, partly in ways that work against transplantation, Liou noted. Children selected for lung transplants now are first put on an intensive course of treatment intended to strengthen them for the surgery, he said, and "conventional treatments have gotten to be very good," he added.

The rules for actual performance of a transplant have also changed, said Dr. Julian L. Allen, chief of the division of pulmonary medicine at the cystic fibrosis center at the Children's Hospital of Philadelphia. He is also co-author of an accompanying editorial in the journal.

Until 2005, all children awaiting a lung transplant were placed on a single list, receiving organs as they became available. Now, the decision to transplant includes consideration of the patient's condition, with sicker children getting the operation sooner, Allen said.

"In some cases, children who were put on intensive therapy were deferred, because they got better," he said. "There was something about the children in that group who didn't get transplanted that made them get better."

The bottom line, Liou said, is that a decision that has always been complex has gotten even more so. "Maybe people will pay attention and try to be more careful about selecting patients for lung transplants," he said.

"You need to be careful about who you refer," Allen said. "You need to see if the results in this study hold true under the current rules. Also, the quality of life after a transplant has to be looked at. We need future studies that evaluate the quality of life."

One complicating factor with younger recipients of lung transplants is the need to be sure that they adhere to the strict regimen needed to prevent rejection of the organ, Allen added. The better success rate with older cystic fibrosis recipients is due partly to their better ability to follow instructions, he said.

More information

There's more on cystic fibrosis at the Cystic Fibrosis Foundation.

THURSDAY, Nov. 15 (HealthDay News) -- Experts on Thursday issued new clinical standards for the treatment of cystic fibrosis (CF).

The guidelines were based on a two-year review of published research on patients aged six and older.

"Physicians treating patients with CF are faced with a growing number of treatment options. We are hopeful that clinicians will find these recommendations to be useful in their care of patients with CF," the guidelines' lead author, Dr. Patrick A. Flume, said in a prepared statement.

CF is a genetic disease that affects the lungs and other organs. It's characterized by thick, sticky mucus that makes it almost impossible for CF patients to fight off germs and infections. The disease is always fatal, and lung disease accounts for 85 percent of deaths among CF patients. However, advances in treatment in the last 60 years have increased life expectancy from just a few years to about 36 years.

Flume and his colleagues looked at a number of treatments and rated their effectiveness. Those with the strongest, most consistent results were given an "A" grade recommendation. They are:

• Inhaled tobramycin -- an antibiotic -- to suppress chronic Pseudomonas aeruginosa infections in CF patients with moderate to severe disease, to improve lung function and reduce exacerbations.
• Dornase alfa, which degrades the free DNA that accumulates in CF mucus, thereby loosening the mucus, promoting airway clearance, improving lung function and reducing exacerbations.

"B" grade recommendations were given for:

• Inhaled tobramycin, to suppress Pseudomonas aeruginosa infections in CF patients with mild disease or who are asymptomatic, to reduce exacerbations.
• Dornase alfa, for CF patients with mild disease who are asymptomatic, to improve lung function and reduce exacerbations.
• Hypertonic saline, which hydrates surface liquid in patients with CF, thereby improving lung function and decreasing exacerbations.
• Beta 2-adrenergic receptor agonists, which relax smooth muscles and dilate bronchial passages, which improve lung function in CF patients, and are well-tolerated.

The guidelines recommend against:

• Systemic corticosteroids in children because of "an excess number of adverse events," including abnormalities in glucose metabolism, cataracts, and percentage of patients "colonized" with Pseudomonas. This recommendation excludes patients with concomitant asthma.
• Inhaled corticosteroids, because there's no clinical benefit. This recommendation excludes patients who also have asthma, however.
• Prophylactic anti-Staphylococcal antibiotics because of the lack of clinical efficacy and an apparent increase in P. aeruginosa infections with their use.

There wasn't sufficient evidence to recommend for or against other types of treatment, said Flume and his colleagues.

The guidelines are published in the second issue for November of the American Journal of Respiratory and Critical Care Medicine.

More information

The March of Dimes has more about cystic fibrosis.