title: Onset age and severity of motor impairment are associated with reduction of myocardial 123I-MIBG uptake in Parkinson's disease.
abstract: OBJECTIVE
  To elucidate the factors associated with severity of cardiac sympathetic nerve involvement in idiopathic Parkinson's disease (PD).
  
  
  METHODS
  (123)I-metaiodobenzylguanidine uptake was examined in 88 patients with PD. The ratio of the uptake in the heart (H) to that in the mediastinum (M) (the H/M ratio) was calculated and correlated with age at onset, age at examination, and disease severity and duration. Twenty five healthy people were also examined as a control.
  
  
  RESULTS
  There was a mild but significant negative correlation between H/M ratio and age at onset (early, r = -0.33, p = 0.002; delayed, r = -0.34, p = 0.001) and between Hoehn and Yahr (H-Y) stage (early, r = -0.30, p = 0.006; delayed, r = -0.32, p = 0.003). There was no significant correlation between disease duration and H/M ratio. When patients with PD were classified into four subgroups on the basis of age at onset (> 62 or < 62 years) and disease severity (H-Y > III or H-Y < or = II), the median H/M ratio of the older and more severe group was significantly lower than that of the younger and less severe group (p = 0.005).
  
  
  CONCLUSIONS
  This study suggests that late onset, high severity PD is associated with myocardial sympathetic dysfunction.
authors.affiliation: Department of Neurology, Nagoya University Graduate School of Medicine, Nagoya, Japan.
authors.forename: K
authors.initials: K
authors.lastname: Hamada
authors.forename: M
authors.initials: M
authors.lastname: Hirayama
authors.forename: H
authors.initials: H
authors.lastname: Watanabe
authors.forename: R
authors.initials: R
authors.lastname: Kobayashi
authors.forename: H
authors.initials: H
authors.lastname: Ito
authors.forename: T
authors.initials: T
authors.lastname: Ieda
authors.forename: Y
authors.initials: Y
authors.lastname: Koike
authors.forename: G
authors.initials: G
authors.lastname: Sobue
mesh_terms: D019797:3-Iodobenzylguanidine / Q000493:pharmacokinetics*; D000367:Age Factors; D017668:Age of Onset; D000368:Aged; D000369:Aged, 80 and over; D001342:Autonomic Nervous System Diseases / Q000000981:diagnostic imaging* / Q000209:etiology*; D005260:Female; D006321:Heart / Q000000981:diagnostic imaging; D006331:Heart Diseases / Q000000981:diagnostic imaging* / Q000209:etiology*; D006801:Humans; D008297:Male; D008482:Mediastinum / Q000000981:diagnostic imaging; D008875:Middle Aged; D010300:Parkinson Disease / Q000150:complications* / Q000000981:diagnostic imaging*; D011237:Predictive Value of Tests; D011877:Radionuclide Imaging; D019275:Radiopharmaceuticals / Q000493:pharmacokinetics*; D012307:Risk Factors; D012720:Severity of Illness Index; D013997:Time Factors
chemical_list: D019275:Radiopharmaceuticals; D019797:3-Iodobenzylguanidine