Neuropathology in older people with disequilibrium of unknown cause

Objective: To identify the neuropathologic features associated with disequi librium in older people. Background: Disequilibrium of unknown cause is com mon in older people. Postmortem specimens from six patients and four contro l subjects, who were part of a longitudinal study of older people with dise quilibrium, were studied. Methods: Cerebral atrophy, ventriculomegaly, and histologic appearance were assessed. Astrocytic hypertrophy, arteriolar scl erotic index (1 - [inner diameter/outer diameter]), and arteriolar density were quantified in the frontal periventricular white matter (FPVWM). Result s: In comparison with control subjects, most patients had prominent frontal atrophy and ventriculomegaly. There were no other gross pathologic finding s, microscopic infarcts, or areas of necrosis in patients or control subjec ts. Markedly reactive astrocytes were found in FPVWM of most patients and n ot in control subjects. Patients tended to have higher mean sclerotic indic es compared with control subjects, but arteriolar density was no different in the two groups. Senile plaques and neurofibrillary tangles were no diffe rent in patients and control subjects except in one patient, in whom AD dev eloped after entry. One patient had cerebral amyloid angiopathy (CAA) witho ut intraparenchymal hemorrhage. Conclusion: Although there was some overlap between the two groups, the main differences between patients and control subjects were prominent frontal atrophy and ventriculomegaly, reactive astr ocytes in FPVWM, and increased arteriolar wall thickness (sclerotic index). These findings suggest an association between subcortical leukoencephalopa thy and disequilibrium in older nonhypertensive patients.