NEW YORK (Reuters Health) - Maintaining adequate vitamin D levels in the body may help guard against bone disease in patients with inflammatory bowel disease (IBD), according to a study in which researchers found a link between inadequate vitamin D levels and lower bone mineral density in a group of IBD patients.

IBD refers to the inflammation of the large or small colon and is characterized by diarrhea, abdominal pain and cramping, bloody stool, weight and appetite loss, and ulceration of the bowel lining. Crohn's disease and ulcerative colitis are two common types of inflammatory bowel disease.

A higher incidence of osteoporosis and fractures is a recognized complication of IBD, but the role of vitamin D insufficiency in IBD-related bone disease is uncertain.

Dr. William D. Leslie and colleagues from the University of Manitoba, Winnipeg, Canada, identified adults recently diagnosed with IBD and measured bone

mineral density and vitamin D levels in a subgroup of 101 subjects.

Only 22 (22 percent) had optimal vitamin D levels, they found. Six patients, or 6 percent, had deficient levels, 38 (38 percent) had insufficient levels, and 35 (35 percent) had marginal levels.

Higher vitamin D levels were associated with greater bone density; lower levels with reduced bone density.

In 94 of the 101 subjects who had repeat BMD measurements roughly 2 years later, researchers saw a positive correlation between a gain in BMD in that interval and vitamin D levels.

"Early optimization of vitamin D may help to prevent bone disease in inflammatory bowel disease," Leslie commented to Reuters Health.

His group's next step, he said, "is to see whether poor vitamin D status or the degree of activity in a patient's inflammatory bowel disease lead to progressive loss in bone density."

SOURCE: American Journal of Gastroenterology, June 2008.