Denufosol helps cystic fibrosis patients, so does vitamin D

There is no cure for cystic fibrosis. Each year, about 1,000 Americans are diagnosed with the disease. 

Now a new ion channel-regulating drug may help kids with cystic fibrosis breathe easier, according to a phase III clinical trial featured online in the American Journal of Respiratory and Critical Care Medicine. 

The trial of more than 350 pediatric patients with cystic fibrosis (CF) found a 24-week treatment with denufosol increased the mean forced expiratory volume at one second or FEV1 by 0.048 L or about 2 percent of the volume seen at baseline. The controls also experienced an increase - 0.003 L- in FEV1. 

For the Transport of Ions to Generate Epithelial Rehydration (TIGER-1) trial, Frank J. Accurso, MD, at the University of Colorado Denver, gave 352 children with cystic fibrosis ages five and older with normal or mildly impaired lung function 60 mg of denufosol three times a day or a placebo for 24 weeks.  All subjects were observed for another 24 weeks. 

In addition to the increase in FEV1 in the double blind phase, the researchers also found  lung function increased in those receiving denufosol by 0.115 L during the open-label phase, or the second 24-weeks of observation.  

Among the controls, an increase (0.078 L) in FEV1 was also observed by the end of the study. 

The improvement by the drug was small. Media reports cited Accurso's team as noting big improvements weren't expected as the drug was not designed to render such an effect. 

Both denufosol and the placebo had similar effects on pulmonary exacerbations, adverse events, and changes in height, weight or body mass index. But sinusitis, rhinorrhea, and headache were more likely observed in those treated with denufosol. 

Cystic fibrosis is an inherited disease of the mucus and sweat glands, according to the National Institutes of Health. The disease affects not only the lungs, but also pancreas, liver, intestines, sinuses and sex organs. 

A diet with abundant vitamins such as vitamin A, E, K and D may help children with cystic fibrosis, according to previous studies. 

A study published in 2007 in Journal of Pediatric Gastroenterology and Nutrition found "Reduced serum levels of vitamin A and E even in the normal range are associated with an increased rate of pulmonary exacerbations in CF." 

Hakim F. from Rambam Medical Center in Haifa, Israel retrospectively examined 597 pulmonary exacerbations in 102 cystic fibrosis patients at the average age of 11 years and found those with low vitamin A and E levels were more likely to suffer pulmonary exacerbations. 

Another study in the September 2010 issue of European Journal of Clinical Nutrition suggests that vitamin D supplements also can help improve lung function in cystic fibrosis patients.  This study led by Pincikova T and colleagues of the Karolinska Institutet in Stockholm, Sweden showed serum 25-hydroxyvitamin D(25OHD) was positively associated with forced expiratory volume in 1λs (FEV1). 

Cystic fibrosis often results in chronic lung inflammation, which is closely correlated with immunoglobulin G (IgG) levels. Vitamin D is known to affect immunomodulatory functions, according to the researchers.  They wanted to assess the association between vitamin D and IgG levels. Pincikova followed 896 cystic fibrosis patients ages 0.53 to 65.9 years enrolled in seven centers in Denmark, Norway and Sweden.  Vitamin D in the form of 25OHD and total IgG were measured and intake of vitamin D was estimated based on a 7-day dietary food record. 

Vitamin D levels in the  blood were positively correlated with FEV1.  

The researchers concluded "Increasing vitamin D intake may positively modulate inflammation in CF (cystic fibrosis). This study supports the proposed role of vitamin D in the immune system during infection and substantiates prospective studies." 

David Liu and editing by Aimee Keenan-Greene