Scientists in the U.S. say they suspect that women who develop Alzheimer's disease or other forms of dementia may start losing weight at least a decade before being diagnosed with the condition.
The researchers at the Mayo Clinic in Rochester, Minnesota say women who developed dementia began losing weight between 11 and 20 years before their diagnosis with the weight loss accelerating in the decade before the diagnosis.
The researchers led by Dr. David Knopman found by the time women were diagnosed they weighed 12 pounds (5.4 kg) less on average than those who did not develop Alzheimer's or dementia.
For the study Knopman's team examined medical records, including detailed weight information, on 219 women from 1990 to 1994 who eventually were diagnosed with Alzheimer's or dementia.
They also tracked the same number of women who did not develop any form of dementia who were of similar age and lived in the same area.
A similar process tracking men who developed dementia and men who did not, did not find any differences in weight.
With a brain disorder such as dementia a persons ability to perform daily activities becomes undermined and the most common form among the elderly is Alzheimer's.
This slow progressive disease begins with mild memory problems and ends with severe brain damage.