Primary Biliary Cirrhosis and Psoriasis Co-Occurrence

According to a study published in Frontiers in Immunology, a one-way causal relationship where primary biliary cirrhosis (PBC) increases the likelihood of psoriasis, but psoriasis does not influence PBC risk.

Researchers investigated the potential causal relationship between PBC and psoriasis, which are frequently observed to co-occur. Using bidirectional Mendelian randomization (MR) analysis, 4 MR methods were employed: inverse-variance weighted (IVW), MR-Egger regression, weighted median, and weighted mode. The aim was to determine whether PBC influences psoriasis risk or vice versa, while sensitivity analyses tested for heterogeneity and pleiotropy to ensure robust findings.

The analysis revealed a significant causal relationship where PBC increases the risk of developing psoriasis. The IVW method showed an odds ratio (OR) of 1.081 (95% CI: 1.028–1.137, P<0.05), indicating that PBC causally contributes to psoriasis risk. Similar results were found across the other MR methods, confirming the consistency of the findings. However, no causal effect of psoriasis on PBC risk was detected (OR: 1.022, 95% CI: 0.935–1.118, P>0.05). MR-Egger regression showed no evidence of genetic pleiotropy affecting the results, and leave-one-out analyses further supported the robustness of the conclusions.

These findings provide new insights into the etiology of PBC and may guide future research on shared mechanisms between these 2 conditions.

Reference
Zhao D, Zhao Q, Xu F, Zhang F, Bai W. Primary biliary cirrhosis and psoriasis: a two-sample Mendelian randomization study. Front Immunol. Published online January 4, 2024. doi:10.3389/fimmu.2023.1264554