TY - JOUR
T1 - Blood harmane (1-methyl-9H-pyrido[3,4-b]indole) concentration in essential tremor cases in Spain
AU - Louis, Elan D.
AU - Benito-León, Julian
AU - Moreno-García, Sara
AU - Vega, Saturio
AU - Romero, Juan Pablo
AU - Bermejo-Pareja, Felix
AU - Gerbin, Marina
AU - Viner, Amanda S.
AU - Factor-Litvak, Pam
AU - Jiang, Wendy
AU - Zheng, Wei
N1 - Funding Information:
We gratefully acknowledge the vital help of the other members of the NEDICES study group: C. Rodríguez, J.M. Morales, R. Gabriel, A. Portera-Sánchez, A. Berbel, A. Martínez-Salio, J. Díaz-Guzmán, J. Olazarán, J. Pardo, J. Porta-Etessam, F. Pérez del Molino, M. Alonso, C. Gómez, C. Saiz, G. Fernández, P. Rodríguez and F. Sánchez-Sánchez. Finally, we also wish to express our sincere thanks to J. de Pedro-Cuesta and J. Almazán, the municipal authorities, family doctors, nurses, and the populations of Getafe, Lista, and Arévalo county. We thank the Junta de Castilla y Leon for the support of the NEDICES study. NEDICES was supported by the Spanish Health Research Agency and the Spanish Office of Science and Technology. The authors gratefully acknowledge the vital help of Drs. José Antonio Molina-Arjona, Ignacio J. Posada, Jesús González de la Aleja, and Antonio Martínez-Salio, for their assistance with the project.
Funding Information:
Elan D. Louis was funded by R01 NS39422 , P30 ES09089 , and CTSA grant number UL1 RR024156 from the National Institutes of Health (Bethesda, MD and Research Triangle, NC) . Pam Factor-Litvak was funded by R01 ES12231 , R01 ES017024 from the National Institutes of Health (Research Triangle, NC). Wei Zheng was funded by R01 NS39422 , R01 ES008146 and R21 ES017055 from the National Institutes of Health (Research Triangle, NC). Julian Benito-León was funded by NIH R01 NS039422 from the National Institutes of Health, Bethesda, MD, USA.
PY - 2013/1
Y1 - 2013/1
N2 - Background: Environmental correlates for essential tremor (ET) are largely unexplored. The search for such environmental factors has involved the study of a number of neurotoxins. Harmane (1-methyl-9H-pyrido[3,4-b]indole) is a potent tremor-producing toxin. In two prior case-control studies in New York, we demonstrated that blood harmane concentration was elevated in ET patients vs. controls, and especially in familial ET cases. These findings, however, have been derived from a study of cases ascertained through a single tertiary referral center in New York. Objective: Our objective was to determine whether blood harmane concentrations are elevated in familial and sporadic ET cases, ascertained from central Spain, compared to controls without ET. Methods: Blood harmane concentrations were quantified by a well-established high performance liquid chromatography method. Results: The median harmane concentrations were: 2.09g-10/ml (138 controls), 2.41g-10/ml (68 sporadic ET), and 2.90g-10/ml (62 familial ET). In an unadjusted logistic regression analysis, log blood harmane concentration was not significantly associated with diagnosis (familial ET vs. control): odds ratio=1.56, p=0.26. In a logistic regression analysis that adjusted for evaluation start time, which was an important confounding variable, the odds ratio increased to 2.35, p=0.049. Conclusions: Blood harmane levels were slightly elevated in a group of familial ET cases compared to a group of controls in Spain. These data seem to further extend our observations from New York to a second cohort of ET cases in Spain. This neurotoxin continues to be a source of interest for future confirmatory research.
AB - Background: Environmental correlates for essential tremor (ET) are largely unexplored. The search for such environmental factors has involved the study of a number of neurotoxins. Harmane (1-methyl-9H-pyrido[3,4-b]indole) is a potent tremor-producing toxin. In two prior case-control studies in New York, we demonstrated that blood harmane concentration was elevated in ET patients vs. controls, and especially in familial ET cases. These findings, however, have been derived from a study of cases ascertained through a single tertiary referral center in New York. Objective: Our objective was to determine whether blood harmane concentrations are elevated in familial and sporadic ET cases, ascertained from central Spain, compared to controls without ET. Methods: Blood harmane concentrations were quantified by a well-established high performance liquid chromatography method. Results: The median harmane concentrations were: 2.09g-10/ml (138 controls), 2.41g-10/ml (68 sporadic ET), and 2.90g-10/ml (62 familial ET). In an unadjusted logistic regression analysis, log blood harmane concentration was not significantly associated with diagnosis (familial ET vs. control): odds ratio=1.56, p=0.26. In a logistic regression analysis that adjusted for evaluation start time, which was an important confounding variable, the odds ratio increased to 2.35, p=0.049. Conclusions: Blood harmane levels were slightly elevated in a group of familial ET cases compared to a group of controls in Spain. These data seem to further extend our observations from New York to a second cohort of ET cases in Spain. This neurotoxin continues to be a source of interest for future confirmatory research.
KW - Environmental risk factors
KW - Epidemiology
KW - Essential tremor
KW - Harmane
KW - Toxin
KW - β-Carboline alkaloid
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U2 - 10.1016/j.neuro.2012.09.004
DO - 10.1016/j.neuro.2012.09.004
M3 - Article
C2 - 22981972
AN - SCOPUS:84872686660
SN - 0161-813X
VL - 34
SP - 264
EP - 268
JO - NeuroToxicology
JF - NeuroToxicology
IS - 1
ER -