Affiliation:
1. Beijing Institute of Heart, Lung and Blood Vessel Diseases
2. Duke University
3. Peking University
Abstract
Abstract
Background
The cognitive problems are prominent in the context of global aging, and the traditional Mendelian randomization method is not applicable to ordered multi-categorical exposures. Therefore, we aimed to address this issue through the development of a new method and to investigate the causal inference of cognitive-related lifestyle factors.
Method
The study sample was derived from the Chinese Longitudinal Healthy Longevity Survey (CLHLS), which included 897 seniors aged 65+. This study used genome-wide association analysis to screen genetic loci as instrumental variables and innovatively combined maximum likelihood estimation to infer causal associations between ordered multi-categorical exposures (diet, exercise, etc.) and continuous outcomes (cognitive level).
Results
The new causal inference method for ordered multi-categorical exposures developed in this study was simple, easy to implement, and able to effectively and reliably discover the potential causal associations between variables. Through this method, we found a potential positive causal association between exercise status and cognitive level in Chinese seniors ( = 1.883, 95%CI: 0.260–3.564), in which there was no horizontal pleiotropy (p = 0.370).
Conclusion
The study provided a new causal inference method applicable to ordered multi-categorical exposures, that addressed the limitations of the traditional Mendelian randomization method.
Publisher
Research Square Platform LLC
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