Relationship between Parkinson’s and Smoking: A Meta-Analysis

Introduction: Parkinson's disease is one of the most important neurodegenerative disorders affecting 1% of the population above 60 years Oxidative stress in the body is the leading cause of Parkinson's disease which leads to the degeneration of dopaminergic neurons in substantia nigra pars compacta leads to decrease in the level of dopamine and it is shown that there is an association between cigarette smoking and PD. Objective: To evaluate the association between Parkinson's disease (PD) with smoking, and determine whether gender, source of controls, the dose of smoking, and year of studies modify the observed effects of smoking on PD. Materials and methods: The studies which were published between October 2008 to October 2018 were searched and selected from science direct Springer, American journal of epidemiology, PubMed, back-references, and scholarly publications from other science databases. Search strategies like Parkinson's disease and smoking, nicotine and Parkinson's disease and nicotine, tobacco, etc. out of these observational studies were chosen i.e., case-control studies were selected. Results: The data of these obtained studies were pooled and analyzed using comprehensive meta-analysis software the results obtained were as follows OR 0.557 at 95% CI (0.436-0.712) the Z-value obtained was -4.681 and the p-value was 0.000 which showed an association between smoking and Parkinson's disease. Conclusion: from the obtained results and despite extensive evidence from epidemiological and basic research studies suggesting that nicotine may represent an effective agent with potential for prevention and alleviation of PD, clinical data vary to a major extent between individuals.