By Robert Preidt
Researchers looked at more than 8,800 people older than 50. After a median period of about eight years, 4.3 percent of celiac patients and 4.4 percent of those without the digestive disease were diagnosed with dementia.
"Celiac disease did not increase the risk of Alzheimer's in this population-based study," said study lead author Dr. Benjamin Lebwohl, assistant professor of medicine and epidemiology at Columbia University Medical Center in New York City.
"We did not find evidence of increased dementia risk prior to the diagnosis of celiac disease, either," he said in a hospital news release.
Researchers did find a slight increase, however, in celiac patients' risk of developing vascular dementia. The second-leading cause of dementia after Alzheimer's disease, vascular dementia results from an interruption of blood supply to the brain.
"We know that patients with celiac disease have a modestly increased rate of cardiovascular disease, and that patients who experience neurologic symptoms have abnormalities on MRIs that mimic vascular disease," Lebwohl said.
Lebwohl added that the findings on vascular dementia were small and could be due to chance.
People with celiac disease cannot tolerate gluten, a protein found in wheat, rye and barley. The researchers said their study refutes claims in some popular books that gluten, wheat and grains have toxic effects on the brain and may be a factor in rising rates of Alzheimer's disease.
Study co-author Dr. Peter Green is a professor of medicine and director of Columbia's Celiac Disease Center. In the news release, he said, "People who promote an anti-grain or anti-gluten agenda sometimes cite our work in celiac disease, drawing far-ranging conclusions that extend well beyond evidence-based medicine.
"We know 'brain fog' is a serious symptom commonly reported by our patients, and it's understandable that people have been worried about a possible connection to dementia. Fortunately, our work ... provides concrete evidence that this particular worry can be laid to rest," he said.
The results of the study were published recently in the Journal of Alzheimer's Disease.