Causal association of sex hormone-binding globulin on gestational hypertension and pre-eclampsia: a two-sample Mendelian randomization study

Pre-eclampsia (PE) and gestational hypertension (GH) are two different categories of hypertensive disorders of pregnancy. Given earlier observational research, the relationship between sex hormone-binding globulin (SHBG) and a higher risk of GH/PE is still up for dispute. Hence, the present investigation aimed to examine the possible link between SHBG and the likelihood of GH/PE. As a first stage, single nucleotide polymorphisms from summary-level genome-wide association studies were tightly screened using quality-control techniques. Afterward, we utilized a two-sample Mendelian randomization (MR) study to examine the causal impact of SHBG on the likelihood of GH/PE. There was no indication of a relationship between blood SHBG level (n = 214,989) and GH/PE (1864 cases and 461,069 controls) in the initial study. Consensus results were obtained from the replicated analysis, which utilized MR estimates based on serum SHBG level(n = 214,989) for GH (4255 cases and 114,735 controls). The findings did not indicate any proof of a cause-and-effect connection between SHBG and the likelihood of GH/PE (odds ratio [OR] = 0.99, 95% confidence interval [CI] = 0.999 − 1.00, p = .34). Replicate analysis also revealed similar patterns (OR = 0.92, 95%CI = 0.82–1.05, p = .21). The above findings were demonstrated to have a strong level of robustness. The findings of this research did not offer definitive proof to endorse the idea that SHBG has a direct causal impact on the likelihood of GH/PE, which goes against numerous widely accepted observational studies. To ascertain the potential processes behind the relationships seen in observational studies, more investigation is needed.