title: Parkinsonian signs and substantia nigra neuron density in decendents elders without PD.
abstract: Substantia nigra (SN) neurons were counted on single, transverse caudal midbrain sections from 217 male participants in the Honolulu-Asia Aging Study, aged 74-97 years at death. Quadrants areas within the SN were determined with a planimeter and neuronal density was expressed as neurons/mm(2) for 10 Parkinson's disease (PD) cases, 29 incidental Lewy body cases, and 178 controls with neither condition. Mean densities in all quadrants were significantly lower in the PD group compared with the other groups (p = 0.006). This relationship was strongest in the ventrolateral quadrant. In a subgroup of 50 controls who were examined with the Unified Parkinson's Disease Rating Scale an average of 2.1 years prior to death, there was an association of stooped posture (p = 0.009), postural instability (p = 0.013), body bradykinesia (p = 0.048), and gait disturbance (p = 0.05) with neuron density in the dorsolateral quadrant; and impaired speech (p = 0.014), abnormal facial expression (p = 0.022), and difficulty rising from a chair (p = 0.032) with neuron density in the dorsomedial quadrant. There was a significant association of increasing number of signs present with decreasing neuron density in both quadrants (p = 0.001 for trend). Low SN neuron density may be the basis for parkinsonian signs in the elderly without PD.
authors.affiliation: Honolulu Department of Veteran's Affairs, Honolulu, HI, USA.
authors.forename: G Webster
authors.initials: GW
authors.lastname: Ross
authors.forename: Helen
authors.initials: H
authors.lastname: Petrovitch
authors.forename: Robert D
authors.initials: RD
authors.lastname: Abbott
authors.forename: James
authors.initials: J
authors.lastname: Nelson
authors.forename: William
authors.initials: W
authors.lastname: Markesbery
authors.forename: Daron
authors.initials: D
authors.lastname: Davis
authors.forename: John
authors.initials: J
authors.lastname: Hardman
authors.forename: Lenore
authors.initials: L
authors.lastname: Launer
authors.forename: Kamal
authors.initials: K
authors.lastname: Masaki
authors.forename: Caroline M
authors.initials: CM
authors.lastname: Tanner
authors.forename: Lon R
authors.initials: LR
authors.lastname: White
mesh_terms: D000367:Age Factors; D000368:Aged; D000369:Aged, 80 and over; D000375:Aging / Q000473:pathology*; D001213:Asian; D002452:Cell Count / Q000379:methods; D006801:Humans; D016631:Lewy Bodies / Q000473:pathology; D008297:Male; D009474:Neurons / Q000473:pathology*; D020734:Parkinsonian Disorders / Q000473:pathology*; D011180:Postmortem Changes; D012720:Severity of Illness Index; D013194:Staining and Labeling; D013378:Substantia Nigra / Q000473:pathology*