Investigating the relationship between psoriasis and venous thromboembolism using systematic review, meta-analysis and Mendelian randomization study.

Background: Numerous studies have investigated the correlation between psoriasis and venous thromboembolism (VTE). However, the findings have not been entirely conclusive. The objective of this study was to assess the association between psoriasis and the risk of VTE by conducting a systematic review and meta-analysis, complemented by Mendelian randomization (MR) analysis to evaluate potential causality.

Methods: In our study, we utilize meta-analysis and MR to delve into the potential relationship between psoriasis and VTE. A comprehensive literature search was conducted across PubMed, Web of Science, and Embase. Different measures of association reported in the original studies - including relative risks (RRs), hazard ratios (HRs), standardized incidence ratios (SIRs), and odds ratios (ORs) - were converted to ORs for consistency using validated methods. MR was subsequently utilized to evaluate the causal impact of psoriasis on the occurrence of VTE.

Results: In the primary analysis, all thromboembolic events - including pulmonary embolism (PE), deep vein thrombosis (DVT), or both - were classified as overall VTE. Meta-analysis demonstrated a higher odd of overall VTE in patients with psoriasis (OR: 1.23, 95% confidence interval (CI): 1.03-1.46). Subgroup analyses revealed that psoriasis was associated with an increased incidence of VTE in European (OR: 1.51, 95% CI: 1.34-1.70) and Asian (OR: 2.02, 95% CI: 1.42-2.88) populations, while no significant association in North American studies (OR: 0.98, 95% CI: 0.88-1.10). The RR group demonstrated a substantial increase in VTE risk among psoriasis patients (RR: 1.30, 95% CI: 1.01-1.68), as did the SIR group (SIR: 1.40, 95% CI: 1.31-1.50) and OR group (OR: 0.95, 95% CI: 0.90-0.99). Conversely, the HR group (HR: 1.19, 95% CI: 0.94-1.51), did not show a significant association. VTE type subgroup analyses were subsequently conducted to separately assess the odds of VTE, PE, and DVT as distinct outcomes. Psoriasis was found to increase the incidence of VTE-only (OR: 1.27, 95% CI: 1.03-1.56), but no significant association was observed with PE (OR: 1.13, 95% CI: 0.70-1.83) and DVT (OR: 0.85, 95% CI: 0.65-1.11). MR suggested that genetically predicted psoriasis is not associated with an increased odd of VTE (inverse-variance weighted OR: 1.000, 95% CI: 0.999-1.001, P = .639).

Conclusion: While the meta-analysis revealed a significantly increased odds of VTE in patients with psoriasis, the MR analysis did not support a causal relationship. These findings suggest a potential observational association without confirming causality.