The Causal Association Between Medication Intake and Increased Risk of Psoriasis

Psoriasis is a chronic, inflammatory, and papulo-squamous skin disorder without a radical cure. Although previous observational analyses have discovered a relationship between medication intake and increased risk of psoriasis, they are susceptible to confounders.

We intend to ascertain if there is a causal association between specific medication intake and increased risk of psoriasis by utilizing the Mendelian randomization (MR) method.

We obtained the genome-wide association study (GWAS) data for medication intake (23 types, N = 1809) from UK Biobank samples. And we sourced the GWAS data for psoriasis from the 8^th release of the FinnGen database, which included 8,075 psoriasis cases and 330,975 healthy control cases. Then a two-sample MR study was performed to determine their causal association, and inverse-variance-weighted MR (IVW-MR) was applied to calculate the effect estimates.

The IVW-MR analysis uncovered a positive correlation between the intake of HMG CoA reductase inhibitors and the increased risk of psoriasis (odds ratio [OR] = 1.167, 95% confidence interval [CI] = 1.084-1.257). Similarly, the use of thyroid preparations (OR=1.080, 95% CI=1.026-1.138), nonsteroidal anti-inflammatory and antirheumatic products (OR=1.406, 95% CI=1.037-1.908), anilides (OR=1.379, 95% CI=1.004-1.894), antihistamines for systemic use (OR=1.341, 95% CI=1.104-1.630), and antihypertensives (OR=1.099, 95% CI=1.016-1.190) were associated with an increased risk of psoriasis. We did not find evidence from IVW-MR for other associations.

Our study offers a causal testimony that the intake of HMG CoA reductase inhibitors, thyroid preparations, nonsteroidal anti-inflammatory and antirheumatic products, anilides, antihistamines for systemic use, and antihypertensives will potentially increase the risk of psoriasis.