Abstract: Objective: To investigate the expression of peripheral blood dynamics related protein 1 (DRP1) and fatty acid binding protein 5 (FABP5) in patients with severe plaque psoriasis (SPP) and their relationship with carotid atherosclerosis. Methods: A total of 158 patients with SPP who were admitted to our hospital from January 2023 to May 2025 were prospectively enrolled as the SPP group. In addition, 79 patients with mild plaque psoriasis (PP) and 79 patients with moderate PP who were admitted during the same period were selected at a ratio of 2∶1 and assigned to the mild PP group and moderate PP group, respectively. Peripheral blood levels of DRP1 and FABP5 were measured by enzyme-linked immunosorbent assay. According to the presence or absence of CAS, patients with SPP were divided into the CAS group and non-CAS group. Pearson correlation analysis was performed to assess the correlations of peripheral blood DRP1 and FABP5 levels with CIMT in SPP patients with CAS. Multivariate Logistic regression analysis (enter method) and receiver operating characteristic (ROC) curves were used to evaluate the predictive value of peripheral blood DRP1 and FABP5 levels for CAS in patients with SPP. Internal validation was performed using 1,000 bootstrap resamples. Results: Serum DRP1 and FABP5 levels progressively increased across the mild PP, moderate PP, and SPP groups (P＜0.017). The incidence of CAS in SPP patients was 44.94% (71/158). Univariate analysis showed that psoriasis duration, psoriasis area and severity index (PASI), diabetes, low-density lipoprotein cholesterol (LDL-C), high-sensitivity C-reactive protein (hs-CRP), DRP1, and FABP5 were associated with CAS in SPP patients (P＜0.05). Serum DRP1 and FABP5 levels were positively correlated with CIMT in SPP patients with CAS (r＝0.710, 0.713, Ps＜0.001). Multivariate logistic regression revealed that longer disease duration (OR＝1.155, 95%CI: 1.032-1.292, P＝0.012), elevated LDL-C (OR＝4.462, 95%CI: 1.623-12.269, P＝0.004), increased hs-CRP (OR＝1.381, 95%CI: 1.131-1.386, P＝0.002), higher DRP1 (OR＝1.467, 95%CI: 1.190-1.807, P＜0.001), and higher FABP5 (OR＝1.614, 95%CI: 1.282-2.034, P＜0.001) were independent risk factors for CAS in SPP patients. The AUCs of DRP1, FABP5, and their combination for predicting CAS in SPP were 0.802, 0.784, and 0.876, respectively, with sensitivities of 0.578, 0.535, and 0.718, and specificities of 0.862, 0.943, and 0.885. Combined detection showed higher diagnostic efficiency compared with either marker alone (P＜0.05). Internal validation with 1,000 bootstrap resamples yielded a C-index of 0.876 for the combined DRP1 and FABP5 model in diagnosing CAS in patients with SPP. Conclusion: Elevated peripheral blood DRP1 and FABP5 levels are independent risk factors for CAS in SPP patients. The combined detection of DRP1 and FABP5 provides superior diagnostic performance compared with either marker alone.

Key words: severe plaque psoriasis, dynamin-related protein 1, fatty acid-binding protein 5, carotid atherosclerosis