Systematic review and meta-analysis of hydrocarbon exposure and the risk of Parkinson's disease. Issue 3 (March 2015)

• Record Type: Journal Article
• Authors: Palin, Oliver; Herd, Clare; Morrison, Karen E.; Jagielski, Alison C.; Wheatley, Keith; Thomas, G. Neil; Clarke, Carl E.
• Is Part Of: Parkinsonism & related disorders. Volume 21:Issue 3(2015)
• Page Start: 243
• Page End: 248
• Publication Date: 2015-03
• Subjects: Parkinson's disease -- Hydrocarbons -- Occupational exposure -- Case-control -- Epidemiology; Parkinson's disease -- Periodicals; Movement disorders -- Periodicals; Movement Disorders -- Periodicals; Nerve Degeneration -- Periodicals; Nervous System Diseases -- Periodicals; Parkinson Disease -- Periodicals; Tremor -- Periodicals; Parkinson, Maladie de -- Périodiques; Parkinson's disease; 616.833
• DOI: 10.1016/j.parkreldis.2014.12.017
• Languages: English
• ISSNs: 1353-8020

Abstract

Abstract: Background: There is no consensus on the association between exposure to hydrocarbons and the risk of Parkinson's disease (PD). We conducted a systematic review and meta-analysis to summarise the epidemiological evidence and included a new large case-control study. Methods: Data were extracted following a predefined protocol. Risk estimates regarding the association between hydrocarbon exposure and PD were consolidated to produce a summary odds ratio (OR), 95% confidence intervals (CI), and p-value. In our case-control study, 1463 PD patients and 685 controls were recruited from clinical trials and completed a structured questionnaire describing their previous working exposure to hydrocarbons and other demographic measures. The association between exposure to hydrocarbons and risk of PD was evaluated using logistic regression. Results: The systematic search identified 13 case-control studies matching the inclusion criteria. The meta-analysis included 3020 PD cases and 6494 controls. The summary OR was 1.32 (95% CI 1.08–1.62, p = 0.006) for hydrocarbon exposure (ever versus never). In the PD GEN study, occupational exposure to hydrocarbons significantly increased the risk of PD (OR = 1.61; 95% CI 1.10–2.36, p = 0.014), and risk dose-dependently increased for subjects exposed greater than 10 years compared to subjects never exposed (OR = 2.19; 95% CI 1.13–4.26, p = 0.021). The addition of PD GEN data increased the total numbers to 4483 PD cases and 7179 controls and strengthened the significant association (summary OR = 1.36; 95% CI 1.13–1.63, p = 0.001). Conclusions: This systematic review supports a positive association between hydrocarbon exposure and PD. Data from prospective studies are required to reinforce the relationship between hydrocarbon exposure and PD. Highlights: We did a systematic review of hydrocarbon exposure and the risk of Parkinson's disease. We included a new large case-control study of hydrocarbons and Parkinson's disease. There was a significant association between hydrocarbons and the risk of Parkinson's disease. Data from prospective studies are required to reinforce this relationship with hydrocarbons.