Association between pathological scar and hypertension: A two-sample Mendelian randomization study

Observational studies have linked pathological scars to hypertension; however, the causality remains ambiguous. In this study, we aimed to explore this issue using Mendelian randomization (MR). We obtained genome-wide association study data for hypertrophic scar and hypertension from the IEU Open genome-wide association study project [hypertension (containing 9851,867 SNPs, observation group of 124,227, and control group of 337,653), hypertrophic scars (containing 16,380,443 SNPs with a sample mass of 207,482), and keloids (containing 24,197,210 SNPs and sample volume of 481,912)]. The inverse variance weighted method and MR-Egger test were used, followed by a sensitivity analysis. With hypertension as the exposure and hypertrophic scar as the outcome, we obtained the IVW analysis results (OR = 0.264, 95% CI = 0.098-0.709, P = .008) and the MR-Egger test results (OR = 0.036, 95% CI = 0.002-0.544, P = .017); for keloid as the outcome, the results of IVW analysis showed OR = 0.592, 95% CI = 0.293-1.195, P = .143. Contrary to the findings of observational studies, our results revealed hypertension as a protective factor against hypertrophic scarring, and was unrelated to keloids.