BOSTON Memory problems that are often dismissed as a normal part of aging may not be so harmless after all.
Noticing you have had a decline beyond the occasional misplaced car keys or forgotten name could be the very earliest sign of Alzheimer's, several research teams are reporting.
Doctors often regard people who complain that their memory is slipping as “the worried well,” but the new studies show they may well have reason to worry, said Maria Carrillo, a senior scientist at the Alzheimer's Association.
One study found that self-reported memory changes preceded broader mental decline by about six years. Another tied these changes to evidence on brain scans that dementia is setting in.
“Maybe these people know something about themselves” that their doctors don't, “and maybe we should pay attention to them,” said Dorene Rentz, a Massachusetts General Hospital psychologist. She helped run one of the studies, which were discussed Wednesday at the Alzheimer's Association International Conference in Boston.
The new studies were on “subjective cognitive decline” – when people first notice they are having trouble, even if they test normal on mental ability tests:
Richard Kryscio at the University of Kentucky led a study of 531 people, average age 73. Those who reported a change in memory or thinking abilities since their last doctor visit were nearly twice as likely to be diagnosed with dementia or mild cognitive impairment about six to nine years later.
Researchers from the French government's health agency and Brigham and Women's Hospital in Boston studied 3,861 nurses at least 70 years old who were asked about memory symptoms and periodically tested for them later. About 900 of them carried a gene that raises their risk for dementia. Among the gene carriers, worry about a single memory symptom predicted verbal memory decline on tests over the next six years. In the others without the gene, worry about three or more memory symptoms was linked to memory decline on tests.
Rebecca Amariglio and other Harvard researchers found that complaints about memory decline matched how much sticky plaque researchers saw on brain scans of 189 people 65 and older. This confirms an earlier study of 131 people that tied memory complaints to these brain plaques, the hallmark of Alzheimer's disease.