Quantitative brain measurements in community-dwelling elderly persons with mild parkinsonian signs

Background: Mild parkinsonian signs (MPS) are a marker of incident dementia. They have been linked with cerebrovascular disease, which can be evaluated using magnetic resonance imaging (MRI). Also, if MPS are a marker for developing Alzheimer-type changes, hippocampal volume on MRI might be diminished in individuals with MPS. Objective: To examine white matter hyperintensity (WMH) volume and total hippocampal volume in elderly individuals with and without MPS. Methods: Community-dwelling elderly persons in northern Manhattan (New York), New York, underwent neurologic examination and brain MRI. The WMH volume (derived from fluid-attenuated inversion recovery-weighted MRIs using a semiautomated thresholding approach) and total hippocampal volume (derived manually) were expressed relative to total cranial volume. Results: Mild parkinsonian signs were present in 111 of 666 participants (16.7%). Mean (SD) relative WMH volume was larger in participants with MPS vs those without MPS (1.70 [1.28] vs 1.17 [1.18]; P<.001). In a multivariate logistic regression analysis adjusting for age, sex, race/ethnicity, years of educational achievement, and depression, relative WMH volume was associated with MPS (odds ratio, 1.26; 95% confidence interval, 1.08-1.47; P=.004). In both unadjusted and adjusted analyses, total relative hippocampal volume was similar in participants with MPS vs those without MPS regardless of cognitive status. Conclusions: In this MRI study of community-dwelling elderly persons, WMH volume was associated with MPS and total relative hippocampal volume was not. These data raise the possibility that vascular disease could have a role in the development of MPS.