Serum Levels of Human Neutrophil Peptides 1–3 (HNP1–3) as Potential Biomarkers in Psoriasis and Associated Comorbidities

Background: Psoriasis is a chronic inflammatory skin disease frequently associated with systemic comorbidities. Human neutrophil peptides 1–3 (HNP1–3), released by neutrophils, have both antimicrobial and proinflammatory effects and may contribute to the pathogenesis of psoriasis and its related conditions. The aim of this study was to evaluate the serum levels of HNP1–3 in patients with psoriasis compared with healthy controls and to assess their association with selected comorbidities and clinical parameters. Methods: In this cross-sectional study, forty-nine patients with psoriasis and forty-nine matched healthy controls were enrolled. Serum HNP1–3 levels were measured using ELISA. Clinical data, including waist-to-hip ratio (WHR), smoking status, and the presence of comorbidities such as psoriatic arthritis (PsA), cardiovascular disease, and pulmonary or autoimmune disorders, were recorded. Results: The mean HNP1–3 levels were significantly higher in the psoriasis patients than in the controls (3.85 ± 0.76 vs. 2.52 ± 0.84 ng/mL; p < 0.001), especially in patients with concomitant PsA (4.21 ± 0.69 ng/mL). Multivariable regression identified increased WHR (β = 1.77, p < 0.01) and smoking (β = 0.45, p < 0.001) as independent predictors of elevated HNP1–3 levels. Positive correlations were also found between HNP1–3 and ESR (r = 0.505, p = 0.019) and IL-6 (r = 0.561, p = 0.008). Conclusions: The elevated serum HNP1–3 levels identified in psoriasis patients—especially those with PsA, central obesity, and smoking history—suggest their potential utility as biomarkers of systemic inflammation. These findings highlight the systemic nature of psoriasis and warrant further research into the clinical utility of HNP1–3 in disease monitoring and risk stratification.