title: The association between infectious burden and Parkinson's disease: A case-control study.
abstract: BACKGROUND
  The etiology of Parkinson's disease (PD) remains unclear. The aim of this study was to examine the association between common pathogenic infections and PD.
  
  
  METHODS
  Antibody titers to common infectious pathogens including cytomegalovirus (CMV), Epstein Barr virus (EBV)，herpes simplex virus type-1 (HSV-1), Borrelia burgdorferi (B. burgdorferi), Chlamydophila pneumoniae (C. pneumoniae) and Helicobacter pylori (H. pylori) were measured by ELISA in serum of 131 PD patients and 141 normal controls. Infectious burden (IB) was defined as a composite serologic measure of exposure to these common pathogens.
  
  
  RESULTS
  Seropositivities toward zero-two, three-four and five-six of these pathogens were found in 11%, 74% and 15% of normal controls while in 4%, 61% and 35% of PD patients, respectively. IB, bacterial burden and viral burden were independently associated with PD. Schwab and England (S&E) scores were negatively correlated with IB in patients with PD. Serum α-synuclein protein levels and inflammatory cytokines (interleukin-1β and interleukin-6) in individuals with higher IB were also significantly higher.
  
  
  CONCLUSIONS
  IB consisting of CMV, EBV, HSV-1, B. burgdorferi, C. pneumoniae and H. pylori is associated with PD. This study supports the role of infection in the etiology of PD.
authors.affiliation: Department of Neurology and Center for Clinical Neuroscience, Daping Hospital, Third Military Medical University, 10 Changjiang Branch Road, Yuzhong District, Chongqing 400042, China.
authors.forename: Xian-Le
authors.initials: XL
authors.lastname: Bu
authors.affiliation: Department of Neurology and Center for Clinical Neuroscience, Daping Hospital, Third Military Medical University, 10 Changjiang Branch Road, Yuzhong District, Chongqing 400042, China.
authors.forename: Xin
authors.initials: X
authors.lastname: Wang
authors.affiliation: Department of Neurology and Center for Clinical Neuroscience, Daping Hospital, Third Military Medical University, 10 Changjiang Branch Road, Yuzhong District, Chongqing 400042, China.
authors.forename: Yang
authors.initials: Y
authors.lastname: Xiang
authors.affiliation: Department of Neurology and Center for Clinical Neuroscience, Daping Hospital, Third Military Medical University, 10 Changjiang Branch Road, Yuzhong District, Chongqing 400042, China.
authors.forename: Lin-Lin
authors.initials: LL
authors.lastname: Shen
authors.affiliation: Department of Neurology and Center for Clinical Neuroscience, Daping Hospital, Third Military Medical University, 10 Changjiang Branch Road, Yuzhong District, Chongqing 400042, China.
authors.forename: Qing-Hua
authors.initials: QH
authors.lastname: Wang
authors.affiliation: Department of Neurology and Center for Clinical Neuroscience, Daping Hospital, Third Military Medical University, 10 Changjiang Branch Road, Yuzhong District, Chongqing 400042, China.
authors.forename: Yu-Hui
authors.initials: YH
authors.lastname: Liu
authors.affiliation: Department of Neurology and Center for Clinical Neuroscience, Daping Hospital, Third Military Medical University, 10 Changjiang Branch Road, Yuzhong District, Chongqing 400042, China.
authors.forename: Shu-Sheng
authors.initials: SS
authors.lastname: Jiao
authors.affiliation: Department of Neurology and Center for Clinical Neuroscience, Daping Hospital, Third Military Medical University, 10 Changjiang Branch Road, Yuzhong District, Chongqing 400042, China.
authors.forename: Ye-Ran
authors.initials: YR
authors.lastname: Wang
authors.affiliation: Department of Neurology and Center for Clinical Neuroscience, Daping Hospital, Third Military Medical University, 10 Changjiang Branch Road, Yuzhong District, Chongqing 400042, China.
authors.forename: Hong-Yuan
authors.initials: HY
authors.lastname: Cao
authors.affiliation: Department of Neurology and Center for Clinical Neuroscience, Daping Hospital, Third Military Medical University, 10 Changjiang Branch Road, Yuzhong District, Chongqing 400042, China.
authors.forename: Xu
authors.initials: X
authors.lastname: Yi
authors.affiliation: Department of Neurology and Center for Clinical Neuroscience, Daping Hospital, Third Military Medical University, 10 Changjiang Branch Road, Yuzhong District, Chongqing 400042, China.
authors.forename: Cheng-Hui
authors.initials: CH
authors.lastname: Liu
authors.affiliation: Department of Neurology and Center for Clinical Neuroscience, Daping Hospital, Third Military Medical University, 10 Changjiang Branch Road, Yuzhong District, Chongqing 400042, China.
authors.forename: Bo
authors.initials: B
authors.lastname: Deng
authors.affiliation: Department of Neurology and Center for Clinical Neuroscience, Daping Hospital, Third Military Medical University, 10 Changjiang Branch Road, Yuzhong District, Chongqing 400042, China.
authors.forename: Xiu-Qing
authors.initials: XQ
authors.lastname: Yao
authors.affiliation: Department of Neurology and Center for Clinical Neuroscience, Daping Hospital, Third Military Medical University, 10 Changjiang Branch Road, Yuzhong District, Chongqing 400042, China.
authors.forename: Zhi-Qiang
authors.initials: ZQ
authors.lastname: Xu
authors.affiliation: Department of Neurology and Center for Clinical Neuroscience, Daping Hospital, Third Military Medical University, 10 Changjiang Branch Road, Yuzhong District, Chongqing 400042, China.
authors.forename: Hua-Dong
authors.initials: HD
authors.lastname: Zhou
authors.affiliation: Department of Neurology and Center for Clinical Neuroscience, Daping Hospital, Third Military Medical University, 10 Changjiang Branch Road, Yuzhong District, Chongqing 400042, China. Electronic address: yanjiang_wang@tmmu.edu.cn.
authors.forename: Yan-Jiang
authors.initials: YJ
authors.lastname: Wang
mesh_terms: D000368:Aged; D000907:Antibodies, Bacterial / Q000097:blood*; D000914:Antibodies, Viral / Q000097:blood*; D025065:Borrelia burgdorferi / Q000276:immunology; D016022:Case-Control Studies; D016993:Chlamydophila pneumoniae / Q000276:immunology; D003587:Cytomegalovirus / Q000276:immunology; D005260:Female; D006090:Gram-Negative Bacteria / Q000276:immunology*; D016480:Helicobacter pylori / Q000276:immunology; D006564:Herpesviridae / Q000276:immunology*; D018259:Herpesvirus 1, Human / Q000276:immunology; D004854:Herpesvirus 4, Human / Q000276:immunology; D006801:Humans; D053583:Interleukin-1beta / Q000097:blood*; D015850:Interleukin-6 / Q000097:blood*; D008297:Male; D008875:Middle Aged; D010300:Parkinson Disease / Q000097:blood*; D012307:Risk Factors; D051844:alpha-Synuclein / Q000097:blood*
chemical_list: D000907:Antibodies, Bacterial; D000914:Antibodies, Viral; D053583:Interleukin-1beta; D015850:Interleukin-6; D051844:alpha-Synuclein
keywords: Alpha-synuclein; Case-control study; Infections; Parkinson's disease; Risk factors