Neuropathological changes in Alzheimer’s disease precede the appearance of clinical symptoms by many years. The progressive nature of Alzheimer’s disease has been illustrated by findings from a longitudinal cohort study involving 531 people aged 73 years on average and free of dementia at baseline.
Subjective memory complaints (SMCs) were reported by 55.7% of participants. These individuals were 2.8 times more likely to develop cognitive impairment during follow-up than those without SMCs. Among participants who died without a diagnosed clinical impairment, SMCs predicted a higher number of neuritic amyloid plaques in the brain at autopsy.
The findings add weight to the hypothesis that SMCs are common and predict future cognitive impairment, say Richard Kryscio, from the University of Kentucky, and co-authors writing in Neurology
(online, 24 September 2014).