A Bidirectional Mendelian Randomization Study of the Causal Association Between Ischemic Stroke, Coronary Heart Disease, and Hydrocephalus.

Background: The association among coronary heart disease, ischemic stroke, and hydrocephalus remains ambiguous.

Objectives: There is a need for a Mendelian randomization study to evaluate the underlying causality between coronary heart disease, ischemic stroke, and hydrocephalus.

Methods: The data source utilized genome-wide association studies, employing a threshold of p < 5 × 10 to identify single nucleotide polymorphisms strongly linked to ischemic stroke and coronary heart disease as instrumental variables (IVs). Five methods-inverse variance weighted (IVW), Mendelian randomization (MR) Egger, Weighted Median, Weighted mode, and Simple mode-utilized the selected IVs to estimate the causality between ischemic stroke, coronary heart disease, and hydrocephalus.

Results: The IVW demonstrated that ischemic stroke and coronary heart disease serve as risk factors for hydrocephalus (odds ratio [OR] = 1.650, 95% CI: 1.066-2.554, p = 0.025; OR = 1.307, 95% CI: 1.023-1.668, p = 0.032). Both the MR-Egger intercept test and Cochran's Q test affirmed the relative reliability of the IVW analysis results. However, no evidence of a reverse causation was observed between hydrocephalus and coronary heart disease or ischemic stroke.

Conclusions: Coronary heart disease and Ischemic stroke may increase the risk of hydrocephalus.