title: Blood harmane (1-methyl-9H-pyrido[3,4-b]indole) concentration in dystonia cases vs. controls.
abstract: BACKGROUND
  Harmane (1-methyl-9H-pyrido[3,4-b]indole) (HA) is a potent neurotoxin that has been linked to two neurological diseases, essential tremor and Parkinson's disease. Blood harmane concentrations [HA] are elevated in patients with both diseases. An important question is whether HA is specifically linked with these diseases or alternatively, is a non-specific marker of neurological illness.
  
  
  OBJECTIVE
  We assessed whether blood [HA] was elevated in patients with a third neurological disease, dystonia, comparing them to controls.
  
  
  METHODS
  Blood [HA] was quantified by high performance liquid chromatography. Subjects comprised 104 dystonia cases and 107 controls.
  
  
  RESULTS
  Mean log blood [HA] in dystonia cases was similar to that of controls (0.41±0.51g(-10)/ml vs. 0.38±0.61g(-10)/ml, t=0.42, p=0.68). In unadjusted and adjusted logistic regression analyses, log blood [HA] was not associated with the outcome (diagnosis of dystonia vs. control): odds ratio (OR)unadjusted=1.11, 95% confidence interval (CI)=0.69-1.79, p=0.68; ORadjusted=1.07, 95% CI=0.58-1.97, p=0.84.
  
  
  CONCLUSIONS
  In contrast to the elevated blood [HA] that has been reported in patients with essential tremor and Parkinson's disease, our data demonstrate that blood [HA] was similar in patients with dystonia and controls. These findings provide the first support for the notion that an elevated blood [HA] is not a broad feature of neurological disease, and may be a specific feature of certain tremor disorders.
authors: GH Sergievsky Center, College of Physicians and Surgeons, Columbia University, New York, NY, USA; Department of Neurology, College of Physicians and Surgeons, Columbia University, New York, NY, USA; Taub Institute for Research on Alzheimer's Disease and the Aging Brain, Columbia University, New York, NY, USA; Department of Epidemiology, Mailman School of Public Health, Columbia University, New York, NY, USA. Electronic address: EDL2@columbia.edu.
authors: Elan D
authors: ED
authors: Louis
authors: Department of Epidemiology, Mailman School of Public Health, Columbia University, New York, NY, USA. Electronic address: prf1@cumc.columbia.edu.
authors: Pam
authors: P
authors: Factor-Litvak
authors: GH Sergievsky Center, College of Physicians and Surgeons, Columbia University, New York, NY, USA. Electronic address: mg3360@cumc.columbia.edu.
authors: Monika
authors: M
authors: Michalec
authors: Purdue University School of Health Sciences, West Lafayette, IN, USA. Electronic address: jiangw@purdue.edu.
authors: Wendy
authors: W
authors: Jiang
authors: Purdue University School of Health Sciences, West Lafayette, IN, USA. Electronic address: wzheng@purdue.edu.
authors: Wei
authors: W
authors: Zheng
mesh_terms: D000368:Aged; D016022:Case-Control Studies; D004421:Dystonia / Q000097:blood*; D005260:Female; D006247:Harmine / Q000031:analogs & derivatives* / Q000097:blood; D006801:Humans; D008297:Male; D008875:Middle Aged
chemical_list: D006247:Harmine; C005010:harman
keywords: Dystonia; Harmane; Neurological disease; Neurotoxin; Tremor