Age at onset is associated with disease severity in Lewy body variant and Alzheimer's disease.

This study investigated the influence of age at onset on cognitive performance, neuropathological and neurochemical features in autopsy-confirmed sporadic Lewy body variant (LBV) and in Alzheimer's disease (AD). We compared 28 early-onset (< or = 70 years) LBV subjects with 28 matched late-onset (> 70 years) subjects. Similarly, we examined the same features in 89 early onset AD and 89 matched late onset AD patients. Patients with early onset LBV and early onset AD declined more rapidly, had more neuritic plaques, and greater neocortical cholinergic loss compared to late onset LBV and late onset AD subjects. Taken together, these results suggest that for both LBV and AD, earlier age at onset may predict a more aggressive disease course.