Psoriasis may increase the risk of lung cancer: a two-sample Mendelian randomization study

Although many studies have indicated that Psoriasis (PsO) could contribute to the risk of lung cancer, no study has reported a clear causal association between them. Our aim was to explore the potential causal association between PsO and the lung cancer risk using Mendelian randomization (MR) design.

To explore a causal association between the PsO and lung cancer, we used large-scale genetic summary data from genome-wide association study (GWAS), including PsO (n = 337 159) and lung cancer (n = 361 586), based on previous observational studies. Our main analyses were conducted by inverse-variance weighted (IVW) method with random-effects model, with a complementary with the other two analyses: weighted median method and MR-Egger approach.

The results of IVW methods demonstrated that genetically predicted PsO was significantly associated with higher odds of lung cancer, with an odds ratio (OR) of 1.06 (95%CI, 1.01-1.12; P = 0.02). Weighted median method and MR-Egger regression also demonstrated directionally similar results (All P < 0.05). In addition, both funnel plots and MR-Egger intercepts indicated no directional pleiotropic effects between PsO and lung cancer.

Our study provided potential evidence between genetically predicted PsO and lung cancer, which suggested that enhanced screening for lung cancer allows early detection of lung cancer.