title: Progression of dopaminergic degeneration in dementia with Lewy bodies and Parkinson's disease with and without dementia assessed using 123I-FP-CIT SPECT.
abstract: OBJECTIVE
  The objective of this study was to investigate the rate of progression of nigrostriatal dopaminergic loss in subjects with dementia with Lewy bodies (DLB), Parkinson's disease (PD) and PD with dementia (PDD) using serial 123I-FP-CIT SPECT imaging. We hypothesised that striatal rates of decline in patients would be greater than in controls, and that DLB and PDD would show similar rates, reflecting the similarity in neurobiological mechanisms of dopaminergic loss between the two disorders.
  
  
  METHODS
  We studied 20 patients with DLB, 20 with PD, 15 with PDD and 22 healthy age-matched controls. Semi-automated region of interest (ROI) analysis was performed on both baseline and repeat scans for each subject and mean striatal uptake ratios (caudate, anterior and posterior putamen) were calculated.
  
  
  RESULTS
  Rates of decline in striatal binding between groups were assessed using ANCOVA. Significant differences between patients and controls were observed in caudate (DLB, PD, PDD, p< or =0.01), anterior putamen (DLB, PDD, p< or =0.05; PD, p=0.07) and posterior putamen (DLB, PD, PDD, p<0.006). Rates of decline were similar between DLB, PD and PDD.
  
  
  CONCLUSIONS
  In conclusion, this is the first study to show that significant progressive dopaminergic loss occurs in DLB and PDD using serial 123I-FP-CIT SPECT. Dementia severity and motor impairment were correlated with decline, suggesting that dopaminergic loss may play an important role in cognitive as well as motor features.
authors.affiliation: Institute for Ageing and Health, Wolfson Research Centre, Newcastle General Hospital, Newcastle University, Westgate Road, Newcastle upon Tyne, NE4 6BE, UK. s.j.colloby@ncl.ac.uk
authors.forename: Sean J
authors.initials: SJ
authors.lastname: Colloby
authors.forename: E David
authors.initials: ED
authors.lastname: Williams
authors.forename: David J
authors.initials: DJ
authors.lastname: Burn
authors.forename: Jim J
authors.initials: JJ
authors.lastname: Lloyd
authors.forename: Ian G
authors.initials: IG
authors.lastname: McKeith
authors.forename: John T
authors.initials: JT
authors.lastname: O'Brien
mesh_terms: D000368:Aged; D003342:Corpus Striatum / Q000000981:diagnostic imaging / Q000378:metabolism; D003704:Dementia / Q000150:complications / Q000000981:diagnostic imaging / Q000378:metabolism; D018450:Disease Progression; D004298:Dopamine / Q000378:metabolism*; D005260:Female; D006801:Humans; D020961:Lewy Body Disease / Q000000981:diagnostic imaging* / Q000378:metabolism*; D008297:Male; D010300:Parkinson Disease / Q000150:complications / Q000000981:diagnostic imaging* / Q000378:metabolism*; D019275:Radiopharmaceuticals / Q000493:pharmacokinetics; D012720:Severity of Illness Index; D015899:Tomography, Emission-Computed, Single-Photon / Q000379:methods; D014326:Tropanes / Q000493:pharmacokinetics*
chemical_list: D019275:Radiopharmaceuticals; D014326:Tropanes; C087552:2-carbomethoxy-8-(3-fluoropropyl)-3-(4-iodophenyl)tropane; D004298:Dopamine