Association Between Systemic Inflammation, Metabolic Syndrome and Quality of Life in Psoriasis Patients

Background/objectives: Psoriasis is a chronic inflammatory autoimmune disease with important systemic and psychosocial impacts. The association with metabolic syndrome (MS) impairs disease severity and negatively influences patient-reported outcomes, particularly their quality of life as measured by the Dermatology Life Quality Index (DLQI). This study aims to investigate the relationship between systemic inflammation, DLQI scores and disease severity, focusing on the persistent impact of MS on patient outcomes after one year of treatment. Methods: This retrospective cross-sectional study included 150 psoriasis patients, with 74 also meeting the diagnostic criteria for MS. Clinical and inflammatory markers such as systemic immune-inflammatory index (SII), cytokines (IL-17A, IL-23), leptin, BMI and triglycerides were analyzed alongside PASI and DLQI scores. Results: Patients with MS had significantly higher PASI and DLQI scores compared to those without MS, reflecting worse disease severity and quality of life (p < 0.01). Elevated SII levels were strongly associated with higher DLQI scores (p < 0.01). Despite considerable reductions in PASI scores over one year of treatment, DLQI scores indicated a persistent negative impact of MS on quality of life. Notably, markers of systemic inflammation, such as SII, leptin and cytokines, correlated positively with both PASI and DLQI scores, highlighting the role of systemic inflammation in disease burden. Conclusions: This study underlines the significant role of systemic inflammation and metabolic comorbidities in amplifying the burden of psoriasis. The persistent impact of MS on quality of life despite clinical improvement underscores the need for comprehensive treatment approaches targeting systemic inflammation, metabolic health and psychosocial factors to improve long-term outcomes.