No Causal Association Between Inguinal Hernia and Aortic Aneurysm Using Mendelian Randomization Analysis

Aortic aneurysm (AA) is a serious disease that affects the aging population worldwide. Potential risk or associated factors, such as inguinal hernia, have been suggested by conventional studies. In the present study, summary statistics data for the associations of inguinal hernia were derived from a large genome-wide association study including 18,791 inguinal hernia cases and 93,955 controls in the UK Biobank. Corresponding data of AA were extracted from FinnGen, comprising 7603 cases and 317,899 controls in Finland. The causal association was assessed using Mendelian Randomization-Egger, weighted median, and inverse variance weighting methods, and compared with observational estimates previously published. Our analysis found no convincing causal effect between genetically predicted inguinal hernia and the risk of AA (odds ratio [OR] = 1.05, 95% confidence interval [CI] = 0.85-1.31, P = .65), abdominal aortic aneurysm (AAA, OR = 1.15, 95% CI = 0.92-1.46, P = .22), and thoracic aortic aneurysm (TAA, OR = 1.05, 95% CI = 0.85-1.30, P = .67). The results are in contrast to previous observational evidence suggesting a potentially common causal association between inguinal hernia and AA. Further research is needed to better understand the interplay between risk factors and their impact on aneurysm development.