Falling may be an early sign of Alzheimer's

By Dr. Ananya Mandal, MDJul 20 2011

In a new study presented at the Alzheimer's Association's annual International Conference in Paris it was reported that older people whose brain scans showed signs of amyloid plaques - an early indicator of Alzheimer's disease - but who were otherwise healthy, had twice the risk of falls as people without brain amyloid.

According to Susan Stark, an assistant professor of occupational therapy and neurology at Washington University in St. Louis, “To our knowledge, this is the first study to identify a risk of increased falls related to a diagnosis of pre-clinical Alzheimer's disease.” She added that the results are consistent with other studies that show mobility problems in people who have very early Alzheimer's or mild cognitive impairment.

In the 8-month-long study, Stark and colleagues measured the rate of falls among 125 older adults, some of whom were cognitively healthy and who showed no memory problems day to day, but whose brain scans revealed the presence of amyloid. Positron emission tomography (PET) scanning was used to detect the presence of amyloid. The participants also contributed samples of cerebrospinal fluid and were asked to keep a journal that tracked how many times they fell.

Results showed that forty-eight people experienced at least one fall. Those with a positive PET scan image had more than double the risk for a fall.

According to Jeffrey Burns, director of the Alzheimer and Memory Program at the University of Kansas School of Medicine, these findings add another piece to the puzzle of understanding Alzheimer's in its earliest stages. “It's a small study, but certainly an interesting finding and likely to be of clinical importance down the road if these scans become available,” says Burns. Someone at an increased risk for falls may benefit from bone medication, physical therapy to help with balance, and be a candidate for early Alzheimer's drug studies, he added.

Maria Carrillo, PhD, senior director of medical and scientific relations at the Alzheimer's Association, said, “This was a small sample. Hundreds of people would have to be studied in terms of calling [maternal history of late-onset disease] a predictor.” One question that the study presents, Carrillo and Cummings agree, is whether the tendency to develop dementia is somehow being passed on through mitochondrial DNA, which is only inherited from the mother.