Neurofibrillary tangles in elderly patients with late onset schizophrenia.

The objective of the present study was to examine whether neurofibrillary tangles densities are increased in elderly patients with late-onset schizophrenia (LOS). A neuropathological examination was performed in 32 consecutive autopsy brain specimens of ten patients with early-onset schizophrenia (EOS; onset of symptoms before the age of 40 years), eight patients with LOS (onset of symptoms after the age of 40 years) and 14 age-matched controls with no known neuropsychiatric disorder. Neurofibrillary tangle densities observed in the CA1 field of the hippocampus, the enthorhinal cortex, and the inferior temporal cortex in patients with LOS, EOS, and controls were not significantly different. All patients with EOS or LOS had Braak stages of III or less, which may correspond to normal aging. Thus, patients with schizophrenia, regardless of the age of onset of their symptoms, are no more prone to the development of Alzheimer's disease than the general population.