AUGUSTA, Ga. The first evidence of blood vessel dysfunction has been found in a small cohort of generally healthy young people with cystic fibrosis, researchers report.
"Even though the lung function in these kids is fine at this point, there is evidence of vascular dysfunction and exercise intolerance," said Dr. Ryan A. Harris, clinical exercise physiologist at the Medical College of Georgia and Institute of Public and Preventive Health at Georgia Health Sciences University. "We think this blood vessel dysfunction could be contributing to their exercise intolerance, which is an independent predictor of mortality in these kids irrespective of their lung function."
The findings raise questions about whether dysfunctional arteries affect patients' ability to exercise, which is already recommended to help combat the disease's hallmark lung complications, and whether exercise can also improve blood vessel function and potentially help forestall cardiovascular disease.
Although their blood pressures tend to be normal and there is no established risk, cystic fibrosis patients have only recently lived long enough to acquire even an accelerated version of cardiovascular disease, said Dr. Katie T. McKie, Director of the Pediatric Cystic Fibrosis Center at the GHS Children's Medical Center. The median predicted age of survival is the mid-30s and nearly half the patients in the United States are over age 18, according to the Cystic Fibrosis Foundation. Fifteen years ago, survival rates for the genetic disease were about half that, McKie said.
The blood vessel or endothelial dysfunction Harris and McKie found in these patients is essentially the reduced ability of blood vessels to respond to important cues, such as dilating when exercise or stress increase the body's demand for blood and oxygen. The dysfunction may be linked to chronic inflammation and oxidative stress which, in turn, impair the body's ability to use nitric oxide,
|Contact: Toni Baker|
Georgia Health Sciences University