A longitudinal cohort study claims that high level of cognitive activity in older age may delay the onset of alzheimer’s disease by nearly 5 years. 1,903 old participants were enrolled for annual cognitive clinical evaluations and neuropathologic examination after death. Cognitive activity at baseline and time of diagnosis along with postmortem markers of alzheimer’s and dementia were assessed. 457 participants developed alzheimer’s disease at the mean age of 88.6 (range 64.1–106.5) years. Results found that higher level of baseline cognitive activity lead to delayed onset of alzheimer’s disease with the mean onset age of 93.6 years. No relation between cognitive activity and markers of alzheimer’s disease and other dementias was seen in 695 participants who underwent a postmortem neuropathologic examination. This study concluded that the level of cognitive activity was directly proportional to the age on alzheimer’s onset.
