title: Premorbid exercise engagement and motor reserve in Parkinson's disease.
abstract: Life-long experiences of cognitive activity could enhance cognitive reserve, which may lead individuals to show less cognitive deficits in Alzheimer's disease, despite similar pathological changes. We performed this study to test whether premorbid physical activity may enhance motor reserve in Parkinson's disease (PD) (i.e., less motor deficits despite similar degrees of dopamine depletion).
  
  
  
  We assessed engagement in premorbid leisure-time exercise among 102 drug naive PD patients who had been initially diagnosed at our hospital by dopamine transporter scanning. Patients were classified into tertile groups based on the frequency, duration, and intensity of the exercises in which they participated.
  
  
  
  Among patients with mild to moderate reductions in striatal dopaminergic activity (above the median dopaminergic activity), the exercise group of the highest tertile showed significantly lower motor scores (i.e., fewer motor deficits, 15.53 ± 6.25), despite similar degrees of dopamine reduction, compared to the combined group of the middle and the lowest tertiles (21.57 ± 8.34, p = 0.01). Nonetheless, the highest tertile group showed a more rapid decline in motor function related to reductions in striatal dopaminergic activity than the other two groups (p = 0.002 with the middle tertile group and p = 0.001 with the lowest tertile group).
  
  
  
  These results suggest that engagement in premorbid exercise acts as a proxy for an active reserve in the motor domain (i.e., motor reserve) in patients with PD.
authors.affiliation: Department of Neurology and Brain Research Institute, Yonsei University College of Medicine, Seoul, South Korea; Department of Neurology, Bundang Jesaeng General Hospital, Seongnam, South Korea.
authors.forename: Mun K
authors.initials: MK
authors.lastname: Sunwoo
authors.affiliation: Department of Neurology and Brain Research Institute, Yonsei University College of Medicine, Seoul, South Korea.
authors.forename: Ji E
authors.initials: JE
authors.lastname: Lee
authors.affiliation: Department of Neurology, Yonsei University Wonju College of Medicine, Wonju, South Korea.
authors.forename: Jin Y
authors.initials: JY
authors.lastname: Hong
authors.affiliation: Department of Neurology and Brain Research Institute, Yonsei University College of Medicine, Seoul, South Korea.
authors.forename: Byung S
authors.initials: BS
authors.lastname: Ye
authors.affiliation: Department of Biostatistics, Yonsei University College of Medicine, Seoul, South Korea.
authors.forename: Hye S
authors.initials: HS
authors.lastname: Lee
authors.affiliation: Department of Nuclear Medicine, Asan Medical Center, University of Ulsan College of Medicine, Seoul, South Korea.
authors.forename: Jungsu S
authors.initials: JS
authors.lastname: Oh
authors.affiliation: Department of Nuclear Medicine, Asan Medical Center, University of Ulsan College of Medicine, Seoul, South Korea.
authors.forename: Jae S
authors.initials: JS
authors.lastname: Kim
authors.affiliation: Department of Neurology and Brain Research Institute, Yonsei University College of Medicine, Seoul, South Korea; Severance Biomedical Science Institute, Yonsei University College of Medicine, Seoul, South Korea.
authors.forename: Phil H
authors.initials: PH
authors.lastname: Lee
authors.affiliation: Department of Neurology and Brain Research Institute, Yonsei University College of Medicine, Seoul, South Korea. Electronic address: yhsohn62@yuhs.ac.
authors.forename: Young H
authors.initials: YH
authors.lastname: Sohn
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D003342:Corpus Striatum / Q000000981:diagnostic imaging; D050483:Dopamine Plasma Membrane Transport Proteins / Q000378:metabolism*; D015444:Exercise / Q000502:physiology*; D005260:Female; D006801:Humans; D008297:Male; D008609:Mental Status Schedule; D008875:Middle Aged; D009043:Motor Activity / Q000502:physiology*; D010300:Parkinson Disease / Q000000981:diagnostic imaging / Q000503:physiopathology* / Q000534:rehabilitation*; D049268:Positron-Emission Tomography; D011446:Prospective Studies; D012189:Retrospective Studies; D012720:Severity of Illness Index; D014326:Tropanes / Q000493:pharmacokinetics
chemical_list: D050483:Dopamine Plasma Membrane Transport Proteins; D014326:Tropanes; C087552:2-carbomethoxy-8-(3-fluoropropyl)-3-(4-iodophenyl)tropane
keywords: Cognitive reserve; Motor cortex; Parkinson' disease: imaging; Parkinson's disease; Parkinson's disease: neurophysiology; Plasticity