ObjectiveTo assess the causal relationship between cervical vertebra related disorders and essential hypertension using a bidirectional two-sample Mendelian randomization study approach. MethodsThe research data comes from the genome-wide association study dataset. Four types of cervical vertebra related disorders: cervicalgia, cervical disc disorders, cervical root disorders, injury of nerves and spinal cord at neck level, as well as data on essential hypertension, were selected for the study. Relevant single nucleotide polymorphisms were selected as instrumental variables to assess the causal relationship between cervical vertebra related disorders and essential hypertension mainly by inverse variance weighted model ratio. Cochran's Q test was used to detect heterogeneity, MR-Egger intercept term and MR-PRESSO was used to detect multiplicity, and leave-one-out method was used for sensitivity analysis. ResultsCervicalgia had a positive causal relationship with the essential hypertension (OR=1.01, 95%CI 1.00 to1.02, P=0.019). Essential hypertension had a positive causal relationship with the cervical disc disorders (OR=4.08, 95%CI 1.57 to10.61, P=0.004). There was no significant causal relationship between cervical root disorders, injury of nerves and spinal cord at neck level and essential hypertension. Reliability assessment indicates that the study results were reliable. ConclusionCervicalgia is a risk factor for essential hypertension; Essential hypertension is a risk factor for cervical disc lesions; There is no correlation between cervical root disorders, injury of nerves and spinal cord at neck level and essential hypertension.
ObjectiveTo investigate the causal relationship between gastroesophageal reflux disease (GERD) and obstructive sleep apnea (OSA) with its typical symptoms (snoring and daytime sleepiness) by using Mendelian randomization (MR). MethodsThe inverse-variance weighted method was used as the main analysis method to assess the causal effect. Sensitivity and pleiotropy analyses were carried out using leave-one-out and MR-Egger analysis, and then heterogeneity tests were conducted. ResultsIn the MR analysis, genetically predicted GERD was associated with a greater risk of OSA (IVW: OR=1.528, 95%CI 1.374 to 1.699, P=5.315E‒15). Additional MR results were consistent with the IVW results, and no pleiotropy or heterogeneity was found. We also discovered a significant causal relationship between GRED and snoring (IVW: OR=0.959, 95%CI 0.949 to 0.969, P=1.507E‒15), and daytime sleepiness (IVW: OR=1.024, 95%CI 1.021 to 1.036, P=4.580E‒5), with no evidence of pleiotropy. ConclusionThe MR study supports a causal effect between GERD and OSA with its typical symptoms (daytime sleepiness and snoring).