Hematologic traits and primary biliary cholangitis: a Mendelian randomization study.

Hematologic abnormalities was observationally associated with the susceptibility of primary biliary cholangitis (PBC). However, the conclusion is still controversial and whether there exists a causal association remains elusive. Here we aimed to explore the causative role of hematological traits in the risk of PBC. We conducted two-sample and multivariable Mendelian randomization analyses based on summary statistics from previous large genome-wide association studies. Totally twelve red blood cell and six white blood cell traits were analyzed. Genetically determined higher hemoglobin level was significantly associated with a reduced risk of PBC (OR: 0.62, 95% CI: 0.47-0.81, P: 5.59E-04). Meanwhile, higher hematocrit level was nominally associated with reduced risk of PBC (OR: 0.73, 95% CI: 0.57-0.93, P: 0.01). These results could help better understand the role of hematological traits in the risk of PBC, and provide potential targets for the disease prevention and treatment.