
Neuroticism, Smoking, and the Risk of Parkinson’s Disease
Author(s) -
Johanna Sieurin,
Yiqiang Zhan,
Nancy L. Pedersen,
Karin Wirdefeldt
Publication year - 2021
Publication title -
journal of parkinson's disease/journal of parkinson's disease (online)
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.747
H-Index - 45
eISSN - 1877-718X
pISSN - 1877-7171
DOI - 10.3233/jpd-202522
Subject(s) - neuroticism , mendelian randomization , odds ratio , medicine , genome wide association study , confidence interval , disease , psychology , cohort study , personality , clinical psychology , psychiatry , single nucleotide polymorphism , genetics , biology , genotype , genetic variants , social psychology , gene
Background: The relationship among neuroticism, smoking, and Parkinson’s disease (PD) is less examined. Objective: To examine the causal associations between neuroticism, smoking initiation, and the risk of PD. Methods: We performed a two-sample Mendelian randomization (MR) design in a network framework. Summary statistics from meta-analyses of genome-wide association studies (GWAS) were based on large cohorts of European ancestry. Study participants were from various cohort studies for neuroticism and smoking initiation, and case-control studies or cohort studies of PD from previously published GWAS meta-analyses. Patients with PD were ascertained from either clinical visit or self-reported. Results: The two-sample MR analysis showed no evidence for a causal association between neuroticism and PD risk (odds ratio [OR] 0.86, 95%confidence intervals [CIs] 0.67 to 1.12). While we did not find a significant association between neuroticism and PD, one SNP, rs58879558 (located in MAPT region), was associated with both neuroticism and PD. We found a significant association of neuroticism on smoking initiation (OR: 1.10, 95%CI: 1.05 to 1.14). Further, our results provided evidence for a protective effect of smoking initiation on the risk of PD (OR: 0.75, 95%CI: 0.62 to 0.91). Conclusion: These findings do not support a causal association of neuroticism on PD risk. However, they provide evidence for a causal relationship between neuroticism and smoking initiation and a strong causal effect of smoking initiation on a reduced risk of PD.