Associations of welding and manganese exposure with Parkinson disease
- 11 September 2012
- journal article
- research article
- Published by Ovid Technologies (Wolters Kluwer Health) in Neurology
- Vol. 79 (11), 1174-1180
- https://doi.org/10.1212/wnl.0b013e3182698ced
Abstract
Objective: To examine associations of welding and manganese exposure with Parkinson disease (PD) using meta-analyses of data from cohort, case-control, and mortality studies. Methods: Epidemiologic studies related to welding or manganese exposure and PD were identified in a PubMed search, article references, published reviews, and abstracts. Inclusion criteria were 1) cohort, case-control, or mortality study with relative risk (RR), odds ratio (OR), or mortality OR (MOR) and 95 confidence intervals (95% CI); 2) RR, OR, and MOR matched or adjusted for age and sex; 3) valid study design and analysis. When participants of a study were a subgroup of those in a larger study, only results of the larger study were included to assure independence of datasets. Pooled RR/OR estimates and 95% CIs were obtained using random effects models; heterogeneity of study effects were evaluated using the Q statistic and I2 index in fixed effect models. Results: Thirteen studies met inclusion criteria for the welding meta-analysis and 3 studies for the manganese exposure meta-analysis. The pooled RR for the association between welding and PD for all study designs was 0.86 (95% CI 0.80–0.92), with absence of between-study heterogeneity (I2 = 0.0). Effect measures for cohort, case-control, and mortality studies were similar (0.91, 0.82, 0.87). For the association between manganese exposure and PD, the pooled OR was 0.76 (95% CI 0.41–1.42). Conclusions: Welding and manganese exposure are not associated with increased PD risk. Possible explanations for the inverse association between welding and PD include confounding by smoking, healthy worker effect, and hormesis.This publication has 55 references indexed in Scilit:
- Occupational exposure in Parkinsonian disorders: A 43-year prospective cohort study in menParkinsonism & Related Disorders, 2011
- Epidemiology and etiology of Parkinson’s disease: a review of the evidenceEuropean Journal of Epidemiology, 2011
- Association of alcohol consumption with selected cardiovascular disease outcomes: a systematic review and meta-analysisBMJ, 2011
- Metal Emissions and Urban Incident Parkinson Disease: A Community Health Study of Medicare Beneficiaries by Using Geographic Information SystemsAmerican Journal of Epidemiology, 2010
- Parkinsonism in patients with a history of amphetamine exposureMovement Disorders, 2010
- Occupational factors and risk of Parkinson's disease: A population‐based case–control studyAmerican Journal of Industrial Medicine, 2009
- A Population-Based Study of Parkinsonism in an Amish CommunityNeuroepidemiology, 2009
- Pesticide exposure and risk of Parkinson's disease: A family-based case-control studyBMC Neurology, 2008
- Environmental risk factors for Parkinson's disease and parkinsonism: the Geoparkinson studyOccupational and Environmental Medicine, 2007
- Familial risks of hospitalization for Parkinson’s disease in first-degree relatives: a nationwide follow-up study from Swedenneurogenetics, 2006