"I don't think we would recommend doctors do it right now, but if the clinical study works, then there's potential that doctors could start using it as soon as the results are known," he said.
Dr. Victor Henderson, a professor of epidemiology and neurology at Stanford University in California, said he agrees with the need for a clinical trial to effectively assess the value of IVIg.
Among people whose records were examined as part of the study reported in Neurology, he noted, those who had received IVIg had other serious illnesses, which might have meant doctors were less likely to burden them further with a diagnosis of Alzheimer's, Henderson said.
He said it's also possible that early signs of Alzheimer's, such as confusion or forgetfulness, were attributed to other drugs they'd taken or the rigors of coping with the other disease, a factor researchers also noted in the study.
"It's a study with results that deserve follow-up confirmation, and the best way to do that is through a properly designed clinical trial," Henderson said. "The findings do make sense as far as our understanding of the basic underlying biology of the disease."
The U.S. National Institute on Aging has more on Alzheimer's disease.
SOURCES: Howard Fillit, M.D., clinical professor, geriatrics, neuroscience and medicine, Mount Sinai School of Medicine, New York City; Victor Henderson, M.D., professor, epidemiology and neurology, School of Medicine, Stanford University, Stanford, Calif.; July 21, 2009, Neurology