- Full (HTML) - Full (PDF) - Related EHP Articles - PubMed:Related Articles - PubMed:Citation - Cited in PMC - Purchase This Issue

Elan D. Louis,^1,2,3 Eva C. Jurewicz,¹ LaKeisha Applegate,¹ Pam Factor-Litvak,⁴ Michael Parides,⁵ Leslie Andrews,⁶ Vesna Slavkovich,⁶ Joseph H. Graziano,^6,7 Spencer Carroll,⁸ and Andrew Todd ⁸

¹Gertrude H. Sergievsky Center, ²Taub Institute for Research on Alzheimer's Disease and the Aging Brain, and ³Department of Neurology, College of Physicians and Surgeons, Columbia University, New York, New York, USA; ⁴Department of Epidemiology, ⁵Department of Biostatistics, and ⁶Department of Environmental Health Sciences, Mailman School of Public Health, Columbia University, New York, New York, USA; ⁷Department of Pharmacology, College of Physicians and Surgeons, Columbia University, New York, New York, USA; ⁸Department of Community and Preventative Medicine, The Mount Sinai School of Medicine, New York, New York, USA

Abstract
Lead is a ubiquitous toxicant that causes tremor and cerebellar damage. Essential tremor (ET) is a highly prevalent neurologic disease associated with cerebellar involvement. Although environmental toxicants may play a role in ET etiology and their identification is a critical step in disease prevention, these toxicants have received little attention. Our objective was to test the hypothesis that ET is associated with lead exposure. Therefore, blood lead (BPb) concentrations were measured and a lifetime occupational history was assessed in ET patients and in controls. We frequency matched 100 ET patients and 143 controls on age, sex, and ethnicity. BPb concentrations were analyzed using graphite furnace atomic absorption spectrophotometry. A lifetime occupational history was reviewed by an industrial hygienist. BPb concentrations were higher in ET patients than in controls (mean ± SD, 3.3 ± 2.4 and 2.6 ± 1.6 µg/dL, respectively ; median, 2.7 and 2.3 µg/dL ; p = 0.038) . In a logistic regression model, BPb concentration was associated with diagnosis [control vs. ET patient, odds ratio (OR) per unit increase = 1.21 ; 95% confidence interval (CI) , 1.05-1.39 ; p = 0.007]. BPb concentration was associated with diagnosis (OR per unit increase = 1.19 ; 95% CI, 1.03-1.37 ; p = 0.02) after adjusting for potential confounders. Prevalence of lifetime occupational lead exposure was similar in ET patients and controls. We report an association between BPb concentration and ET. Determining whether this association is due to increased exposure to lead or a difference in lead kinetics in ET patients requires further investigation. Key words: epidemiology, essential tremor, etiology, lead, occupational exposure. Environ Health Perspect 111:1707-1711 (2003) . doi:10.1289/ehp.6404 available via http://dx.doi.org/ [Online 3 July 2003]

Address correspondence to E.D. Louis, Unit 198, Neurological Institute, 710 West 168th Street, New York, NY 10032, USA. Telephone: (212) 305-3665. Fax: (212) 305-1304. E-mail: EDL2@columbia.edu

This work was supported by R01 NS39422, P30 ES09089, and RR00645 (General Clinical Research Center) from the National Institutes of Health.

The authors declare they have no conflict of interest.

Received 22 April 2003 ; accepted 3 July 2003.