Childhood obesity and hypertension in pregnancy: a two-sample Mendelian randomization analysis

The causal relationship between childhood obesity and hypertension in pregnancy remains unclear. To examine the causal association between childhood obesity and hypertension in pregnancy, two-sample Mendelian randomization analysis was applied.

Single-nucleotide polymorphisms (SNPs) associated with childhood obesity were obtained from a published genome-wide association study (GWAS) of 13 848 European individuals. Summary-level data for hypertension in pregnancy were obtained from the FinnGen consortium (11534 cases and 162212 controls). Inverse-variance weighted analysis, weighted-median analysis, and Mendelian randomization-Egger regression were conducted in this Mendelian randomization analysis. Sensitivity analyses were conducted to confirm the accuracy and robustness of our results.

Genetically determined childhood obesity significantly affects hypertension in pregnancy by IVW [odds ratio (OR) = 1.161, 95% confidence interval (CI) 1.086-1.039; P = 9.92 × 10 -6 ] and weighted median (OR = 1.123, 95% CI 1.038-1.214; P  = 0.004). These results were validated by multiple sensitivity analyses.

A causal effect between genetically predicted childhood obesity and the risk of hypertension in pregnancy was identified. The prevention of hypertension in pregnancy should be promoted in populations with childhood obesity.