Data from: Risky behaviors and Parkinson’s disease: a Mendelian randomization study

Objective: To examine causal associations between risky behavior
phenotypes on Parkinson’s disease using a Mendelian randomization
approach. Methods: We used two-sample Mendelian randomization to generate
unconfounded estimates using summary statistics from two independent,
large meta-analyses of genome-wide association studies on risk taking
behaviors (n=370,771-939,908) and Parkinson’s disease (cases: n=9581,
controls: n = 33,245). We used inverse variance weighted as the main
method for judging causality. Results: Our results support a strong
protective association between the tendency to smoke and Parkinson’s
disease (OR=0.714 per log odds of ever smoking; 95% CI=0.568-0.897;
p-value=0.0041; Cochran Q test; p-value=0.238; I2 index=6.3%).
Furthermore, we observed risk association trends between automobile speed
propensity as well as the number of sexual partners and Parkinson’s
disease after removal of overlapping loci with other risky traits
(OR=1.986 for each standard deviation increase in normalized automobile
speed propensity; 95% CI=1.215-3.243; p-value=0.0066, OR=1.635 for each
standard deviation increase in number of sexual partners; 95%
CI=1.165-2.293; p-value=0.0049). Conclusion: These findings provide
support for a causal relationship between general risk tolerance and
Parkinson’s disease and may provide new insights in the pathogenic
mechanisms leading to the development of Parkinson’s disease.