THURSDAY, Nov. 20 (HealthDay News) -- Higher levels of estrogen during ovulation may explain why women with cystic fibrosis tend to fare worse than men with the respiratory disease, researchers at the University of North Carolina report.

The authors of the study, published in the Nov. 20 issue of the Journal of Clinical Investigation, suggest that drugs that reduce estrogen levels, such as tamoxifen, might be helpful in fighting this devastating disease.

The evidence is still preliminary, however.

"There's not an immediate clinical connection to this," said Dr. Michael Konstan, director of the Cystic Fibrosis Center at Rainbow Babies & Children's Hospital, University Hospitals Case Medical Center in Cleveland. "We need to understand a lot more about the role estrogen plays in cystic fibrosis. What this clearly does is raise our awareness that there are sex-related differences."

Women with cystic fibrosis tend to have worse disease and shorter life spans than men. Although members of both genders generally now live into their 30s, men live an average of about three years longer, said senior study author Robert Tarran, an assistant professor in the Cystic Fibrosis/Pulmonary Research & Treatment Center at the University of North Carolina, Chapel Hill.

That gap has narrowed, largely thanks to more aggressive infection treatment in women.

People with cystic fibrosis have mutations in the cystic fibrosis transmembrane conductance regulator (CFTR) gene, which reduces the ability of chloride ions to travel across cell membranes, the researchers said.

Chloride helps hydrate the lungs by bringing water along with it, basically to hydrate the mucous so that mucous keeps moving through the airways, taking disease-causing bacteria and other organisms with it.

In a person without cystic fibrosis, the chloride channel is wide open, allowing chloride to enter the lungs. Not so in cystic fibrosis patients. Due to a lack of hydration, mucous gets thicker and doesn't move, essentially trapping bacteria, allowing it to linger and fester illness.