Kennedy Krieger Institute receives grant for Alzheimer's disease research in Down syndrome patients

NIH grant will fund research to establish criteria for determining Alzheimer's disease, leading to early intervention

Early signs of Alzheimer's disease can be difficult to distinguish from the normal aging process in any older adult. For adults with Down syndrome, who are particularly vulnerable to Alzheimer's disease, it is even more so. Because effective intervention needs to begin as early in the disease process as possible, prior to the onset of the irreversible impacts on the brain that are characteristic of this devastating disease, early diagnosis is of critical importance. To address crucial gaps in knowledge about Alzheimer's disease in adults with Down syndrome, the Kennedy Krieger Institute has been awarded an $8.5 million grant from the National Institutes of Health (NIH).

The grant awarded by the Eunice Kennedy Shriver National Institute of Child Health and Human Development: Intellectual and Developmental Disabilities Branch will provide for the continuation of Kennedy Krieger's Aging and Dementia in Adults with Down syndrome program through May 31, 2015. Begun in 1987 and drawing on the diverse talents of researchers from the Kennedy Krieger Institute, the New York State Institute for Basic Research on Developmental Disabilities and Columbia University Medical Center, this program has developed into one of the largest research efforts of its kind in the world. Its earlier studies showed that risk for dementia among adults with Down syndrome was lower than expected in their 30s and early 40s, but increased substantially thereafter, much as Alzheimer's disease risk increases in the overall population from the late 60s onward. Earlier findings also revealed that some health-related factors influence whether a specific individual with Down syndrome will be at higher or lower risk. They also showed that risk of Alzheimer's disease for adults with intellectual disability who do not have Down syndrome seems to be similar to what it is in the general population.

The program will now undertake a variety of projects to extend the understanding of the onset and progression of Alzheimer's disease within the older population with Down syndrome to its earliest stage of clinical impact. Hopefully, the findings can have direct implications for promoting more successful aging for adults with DS.

These projects will:

• Conduct studies to determine if risk for Alzheimer's disease within the elderly population with Down syndrome might be associated with insulin resistance;
• Develop empirically validated methods for identifying the presence of mild cognitive impairment (state of mind impairment that is intermediate between declines associated with lifespan brain aging and the deficits that occur in conjunction with dementia) in adults with Down syndrome, differentiating this condition from cognitive changes associated with developmentally appropriate aging;
• Determine the role of basic biological mechanisms that underlie Alzheimer's disease, including altered patterns of DNA methylation (a chemical modification in DNA) and other observed characteristics within this population, including aging-selected processes
• Ascertain the contribution of genetic variants that may influence cognitive function, risk for Alzheimer's disease and age at onset of Alzheimer's disease in adults with DS.

"We have learned that age of onset Alzheimer's disease varies considerably across individuals with Down syndrome, and that old-age associated dementia might be delayed when as yet to be defined advantageous conditions exist," said Wayne Silverman, Ph.D., Director of Intellectual Disabilities Research at Kennedy Krieger. "This suggests exciting prospects for identifying these conditions, and based on this information, promoting successful aging for a far greater proportion of adults with Down syndrome, and perhaps other populations at risk. In addition, our research could provide insights into treatments to slow the progression of Alzheimer's disease in affected individuals, and this promise reinforces the need for early diagnosis."