The Indiana Alzheimer Disease Center at the Indiana University School of Medicine will get $9.1 million over the next five years from the National Institutes of Health.

The grant is the fifth consecutive five-year grant the Alzheimer Disease Center has received from NIH to support research to understand the causes and potential treatments for Alzheimer’s and other forms of dementia. It is the center's largest grant to date.

The IU center is one of 29 similar centers around the country funded by the NIH. Alzheimer’s and other dementias afflicted 36 million people worldwide in 2010. That number could triple in the next four decades as the size of the world’s elderly population surges, according to a report from Alzheimer’s Disease International.

Scientists are unsure what causes Alzheimer’s disease and there is no effective treatment for the disease. Drug companies, including Indianapolis-based Eli Lilly and Co., have poured money into finding a drug that reverses the effects of the disease.

One Lilly drug failed spectacularly last year in a clinical trial, actually worsening the disease in some patients. Lilly expects to report results from a trial of a second drug in mid- to late-2012.

Recent dementia research has enabled investigators and physicians to recognize that there are many types of Alzheimer’s disease and dementias, said Dr. Bernardino Ghetti, director of the Indiana Alzheimer Disease Center.