Savica, Rodolfo

ABSTRACTObjective: The purpose of this study was to examine the discrepancies between the clinical diagnosis of parkinsonism and neuropathological findings in a population‐based cohort with parkinsonian disorders.Background: The specific clinical diagnosis of parkinsonism is challenging, and definite confirmation requires neuropathological evaluation. Currently, autopsies are seldom performed, and most brain autopsies represent atypical or diagnostically unresolved cases.Methods: We used a defined population‐based incidence cohort with clinical parkinsonism (n = 669) from the Rochester Epidemiology Project in Olmsted County, Minnesota, 1991‐2010. We reviewed reports of all patients who underwent neuropathologic examination at autopsy (n = 60; 9%) and applied consensus pathologic guidelines for neurodegenerative disease diagnosis.Results: Among the 60 patients examined pathologically, the median time from the last recorded clinical diagnosis to death was 7 years (range from 2 to 17 years). Clinical–pathological concordance was found in 52 cases (86.7%), whereas 8 (13.3%) had a clinical‐pathological discrepancy. Four patients with a clinical diagnosis of idiopathic Parkinson's disease had no pathological evidence of Lewy bodies or α‐synucleinopathy; of these, pathological diagnoses were Alzheimer's disease (2 cases), progressive supranuclear palsy (1 case), and vascular parkinsonism (1 case). Two patients with clinical diagnoses of "dementia with Lewy bodies" and one patient with an "unspecified parkinsonism" had a pathological diagnosis of Alzheimer's disease without concomitant α‐synuclein lesions. One patient with clinically diagnosed "progressive supranuclear palsy" had indeterminate pathological findings without α‐synuclein or Aβ‐ or tau‐immunoreactive lesions at autopsy.Conclusions: Overall, the clinical diagnoses of parkinsonian subtypes had good concordance with pathological confirmation (86.7%). However, clinical–pathological discrepancies were documented in 13.3%. © 2017 International Parkinson and Movement Disorder Society

Objectives To determine the cross‐sectional association between cerebral amyloid‐beta (A β ) deposition and gait. Design Cross‐sectional. Setting Population‐based cohort study in Olmsted County, MN . Participants Cognitively normal individuals (n = 611), aged 50 to 69 years, enrolled in the Mayo Clinic Study of Aging with concurrent PiB‐ PET imaging and gait assessment. Participants with a history of stroke, alcoholism, Parkinson's disease, subdural hematoma, traumatic brain injury, or normal pressure hydrocephalus were excluded. Measurements PiB‐ PET SUVR was measured in prefrontal, orbitofrontal, parietal, temporal, anterior cingulate, posterior cingulate, and motor‐specific regions of interest ( ROI s). Gait parameters (speed, cadence, stride length, double support time, and intra‐individual stance time variability) were measured using GAITR ite ® instrumentation. Linear regression models were adjusted for age, sex, body mass index, education, APOE ε 4 allele, Charlson comorbidity index, and depression. In secondary analyses, we additionally adjusted for neurodegeneration (hippocampal volume, FDG PET SUVR , and cortical thickness) in AD ‐associated regions. Results In fully adjusted models including neuroimaging measures of neurodegeneration, higher PiB‐ PET SUVR across all ROI s was associated with slower gait speed ( P < .05 except for the parietal ROI ), lower cadence and longer double support time ( P ≤ .05 except for the motor ROI ), and greater stance time variability ( P < .05). In sex‐stratified analyses, the association between higher PiB‐ PET SUVR across all ROI s and measures of gait was only present among women. Conclusion PiB‐ PET SUVR across ROI s, independent of general measures of AD ‐associated neurodegeneration, is associated with poorer performance on multiple gait parameters among cognitively normal women, aged 50 to 69 years. Longitudinal studies are needed to determine whether A β predicts gait decline in both women and men.