**3. Results**

The demographic data of the patients included in the study are listed in Table 1. BMI was significantly higher in the psoriasis group than in the control group (*p* = 0.001). Likewise, the BMI in psoriasis patients was significantly and positively correlated with PASI and BSA (Spearman's correlation coefficients 0.5 and 0.56; *p* = 0.0007 and *p* = 0.0001, respectively). The healthy volunteers were nonsmokers. They were significantly younger (*p* = 0.01), and had significantly lower systolic blood pressure (*p* = 0.04) than the patients qualifying for MTX treatment. Therefore, the 10-year risk of fatal cardiovascular disease and atherosclerosis risk (estimated via the European Risk Chart SCORE) among the healthy volunteers were significantly lower than the corresponding risks among psoriasis patients assigned to receive MTX (*p* = 0.001).


**Table 1.** Demographic characteristics of the study groups at baseline (W0).

Abbreviations: MTX: patients qualified for treatment with methotrexate; ADA: patients qualified for treatment with adalimumab; BMI: body mass index; SCORE: estimation of the risk of fatal cardiovascular disease events over the next 10-year period via Systematic Coronary Risk Evaluation charts. <sup>1</sup> One-way ANOVA model, <sup>2</sup> χ<sup>2</sup> test, <sup>3</sup> Kruskal–Wallis tests, <sup>4</sup> nonrandomized group structure, <sup>5</sup> no level of differentiation between the study groups, <sup>6</sup> no significant differentiation was found by testing the hypothesis with the Kruskal–Wallis test, and there are no post hoc results, \* post hoc test: MTX vs. ADA, \*\* post hoc test: MTX vs. control, \*\*\* post hoc test: ADA vs. control.

Figures 1 and 2 show the levels of VCAM-1 and E-selectin in patients depending on the ten-year risk of fatal cardiovascular disease estimated via SCORE charts. At baseline, the serum levels of VCAM-1 and E-selectin were significantly higher in patients with an estimated SCORE risk >= 10% compared to patients with a risk of <1% (*p* = 0.02 and *p* = 0.012, respectively).

The evaluation of the severity of psoriasis is shown in Table 2. Patients who qualified for treatment with ADA presented more severe psoriatic lesions than those who qualified for MTX therapy. As shown in Table 3, baseline VCAM-1 and E-selectin levels were significantly correlated with disease activity (PASI and BSA) in psoriasis patients. Interestingly, when examining only the patients assigned for treatment with MTX or ADA, the correlation between these values was not significant. Table 4 shows the VCAM-1 and E-selectin levels at W0 and W12 in groups of patients treated with MTX and ADA. In the control group, only W0 values were noted, as the group included healthy volunteers who did not require treatment.

**Figure 1.** Vascular cell adhesion molecule 1 serum levels in patients with ten-year risk of fatal cardiovascular disease estimated via SCORE charts. Abbreviations—VCAM-1: vascular cell adhesion molecule 1, SCORE risk: ten-year risk of fatal cardiovascular disease estimated via SCORE (Systemic Coronary Risk Evaluation) charts.

**Figure 2.** E-selectin serum levels in patients with ten-year risk of fatal cardiovascular disease estimated via SCORE charts. Abbreviations—SCORE risk: ten-year risk of fatal cardiovascular disease estimated via SCORE (Systemic Coronary Risk Evaluation) charts.

**Table 2.** Severity of psoriasis (Psoriasis Area and Severity Index (PASI) and Body Surface Area (BSA)) during the study period.


Abbreviations: PASI: Psoriasis Area and Severity Index; BSA: body surface area; W0: baseline; W12: end of the study; <sup>1</sup> Wilcoxon test.

**Table 3.** Correlation of VCAM-1 and E-selectin levels with PASI and BSA at W0.


Abbreviations: VCAM-1: vascular cell adhesion molecule 1; Ps: psoriasis patients; MTX: patients qualified for treatment with methotrexate; ADA: patients qualified for treatment with adalimumab; PASI: Psoriasis Area and Severity Index; BSA: body surface area.


**Table 4.** VCAM-1 and E-selectin serum levels at W0 and W12.

Abbreviations: VCAM-1: vascular cell adhesion molecule 1; W0: baseline; W12: end of the study; MTX: patients qualified for treatment with methotrexate; ADA: patients qualified for treatment with adalimumab; C: control group. <sup>1</sup> Wilcoxon test, <sup>2</sup> Kruskal–Wallis test, and <sup>3</sup> Mann–Whitney test.

At W0, the highest levels of VCAM-1 and E-selectin were found in the subjects assigned to receive ADA, and the lowest levels were noted in the control group. Regarding the plasma levels of VCAM-1, a comparison between the groups showed significant differences among patients starting treatment with ADA versus MTX (*p* = 0.01) and versus the control group (*p* = 0.000002). Differences were also significant between patients starting treatment with MTX and the control group (*p* = 0.02). With regard to the levels of E-selectin, significant differences were found among patients starting treatment with ADA versus MTX (*p* = 0.027) and versus the control group (*p* = 0.00001). Furthermore, significant differences were observed in patients starting treatment with MTX versus the control group (*p* = 0.034). At W12, the difference between the MTX and ADA groups in terms of the levels of both E-selectin (*p* = 0.000005) and VCAM-1 (*p* = 0.000005) was also significant. A significant decrease was noted in the VCAM-1 serum levels (W0 vs. W12) in patients treated with ADA (*p* = 0.02) or MTX (*p* = 0.008). The reduction in E-selectin level was significant only in patients treated with MTX (*p* = 0.004).

### **4. Discussion**

The results of our study highlight a relationship between the severity of psoriasis as described via PASI and BSA with BMI and the levels of VCAM-1 and E-selectin. They also prove the relationship between the level of studied particles and the ten-year risk of fatal cardiovascular events estimated via SCORE charts. A significant decrease in the serum levels of both studied adhesion molecules was observed in patients receiving MTX. However, only VCAM-1 levels decreased in patients treated with ADA.

The interaction of endothelial adhesion molecules (such as VCAM-1) with selectins (including E-selectin) mediates the migration of activated T cells and macrophages from blood vessels. It also initiates adherence between the vascular endothelium and neutrophils, monocytes, eosinophils, and T lymphocytes during the inflammatory process, resulting in plaque formation in both psoriasis and atherosclerosis [17–19]. Several studies showed higher levels of E-selectin and VCAM-1 in psoriasis [19–22]. The E-selectin serum level is correlated with the severity of psoriasis (as indicated by PASI), so it appears to be an indicator of disease activity [21]. Furthermore, Szepietowski et al. confirmed that the plasma levels of E-selectin significantly decreased after treatment in psoriasis patients [19].

The present study demonstrated the highest VCAM-1 and E-selectin levels in the group of patients assigned to receive ADA, lower values in patients beginning MTX treatment, and the lowest values in the control group. Baseline VCAM-1 and E-selectin levels were significantly and negatively correlated with PASI and BSA in psoriasis patients. Interestingly, the correlation between these levels was not significant after the patients were divided into MTX and ADA treatment groups. Similarly, BMI was significantly correlated with the severity and extent of skin lesions (as indicated by PASI and BSA) in psoriasis patients. No correlation of BMI with either VCAM-1 or E-selectin was found. A high BMI appears to be positively correlated with the severity of psoriasis and defines the clinical response

to systemic treatment [23–25]. Long-term anti-TNF-alpha therapy was related to BMI elevation in psoriasis patients [26,27].

Few reports demonstrated the correlation of adhesion molecules with BMI. Most of them concerned E-selectin, whose level positively correlated with BMI [28–30]. However, Abd El-Kader et al. demonstrated that a reduction in BMI resulted in the modulation of VCAM-1 levels in obese patients with type 2 diabetes [31]. The essential mechanism of action of MTX in psoriasis might relate to a decrease in E-selectin expression during treatment. Torres-Alvares et al. showed that a reduced expression of E-selectin and VCAM-1 in the blood vessels of psoriasis patients after therapy [13,14]. Endothelial function, which is significantly altered in psoriasis patients, may also improve during treatment with TNF-alpha inhibitors. Furthermore, several studies provided evidence of a decrease in E-selectin levels in the sera of psoriasis patients during treatment with infliximab or ADA [2,10,15,32].

In our study, E-selectin and VCAM-1 levels significantly decreased during MTX treatment. Moreover, contrary to E-selectin levels, the decrease in VCAM-1 was significant in patients treated with ADA. The results suggest that endothelial function and the cardiovascular risk of patients with plaque psoriasis are influenced to a larger extent by MTX than ADA.

The most significant limitations of our study were the low number of patients (34 psoriasis patients and eight healthy volunteers), short observation time (12 weeks), and volunteer self-selection of the control group. Volunteer serum samples were not obtained for VCAM-1 and E-selectin determination at W12 because, as healthy individuals, they were not treated. The present results will be verified in a larger study group over an extended period to draw more general conclusions, including the impact of systemic therapy of psoriasis on cardiovascular risk.

#### **5. Conclusions**

The results of our study demonstrate a possible impact of psoriasis itself and its systemic treatment on serum E-selectin and VCAM-1 levels. Therefore, they indicate the risk of developing cardiovascular disease. VCAM-1 and E-selectin serum levels appear to be correlated with psoriasis severity as indicated by PASI and BSA. After 12 weeks of MTX administration, E-selectin and VCAM-1 levels significantly decreased. However, treatment with ADA resulted in a significant decrease only in VCAM-1 levels. Therefore, compared to ADA, MTX may have a greater impact on the levels of adhesion molecules, so it might help determine the risk of cardiovascular disease development in psoriasis patients.

**Author Contributions:** Conceptualization, N.Z. and A.O.-S.; data curation, N.Z., J.C., J.J.N., andW.Z.; investigation, N.Z. and J.C.; methodology, J.C.; resources, N.Z., A.K.-Z., andW.O.; supervision, A.O.-S. andW.P.; writing—original ˙ draft, N.Z.; writing—review and editing, N.Z. and A.O.-S. All authors have read and agreed to the published version of the manuscript.

**Funding:** This study was supported by the Ministry of Science and Higher Education (Ministerstwo Nauki i Szkolnictwa Wy ˙zszego) of Poland, Grant No. 61.610. 001-300.

**Acknowledgments:** The authors would like to thank Abbvie for its help in purchasing research reagents.

**Conflicts of Interest:** The authors declare no conflict of interest.

#### **References**


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