Influenza della sindrome metabolica sul raggiungimento della "??minimal disease activity"? e delle sue componenti in pazienti con artrite psoriasica in terapia con inibitori del TNF-alpha.

Introduction: Psoriatic arthritis (PsA) is a chronic inflammatory arthropathy associated with skin and/or nail psoriasis. Several studies have shown a high prevalence of metabolic syndrome (MetS) in PsA patients. Aim: The aim of this study was to evaluate the influence of MetS on the achievement of minimal disease activity (MDA) and its components in PsA patients in therapy with inhibitors of TNF-alpha with a follow-up period of 24 months. Patients and Methods: A cohort of PsA patients, classified on the basis of CASPAR criteria, was assessed at the University of Padova and at University Federico II of Naples. Inclusion criteria were both sexes, age > 18 years, starting therapy with anti-TNF-alpha, stable medical conditions and no rheumatic diseases other than PsA. Exclusion criteria were previous use of biologic therapy and concomitant use of steroids. Patients'?? data were collected at baseline (T0), and after 12 months (T1) and 24 months (T2) of therapy. Assessment of metabolic and disease activity parameters was performed at each visit. The NCEP-ACT III criteria were used to identify subjects with MetS and the MDA criteria to evaluate the disease activity. Results: On the basis of the inclusion and exclusion criteria, 330 subjects were included in the study. One hundred and ninety-six patients (59.3 %) were classified as having MetS. After 24 months of treatment, 157 patients (47.8%) out of 330 achieved MDA. Among patients not achieving MDA, 134 (77.4 %) had MetS. Univariate analysis indicated that patients with metabolic syndrome were less likely to achieve MDA than patients without metabolic syndrome (OR 0.45, p < 0.001). This inverse association remained statistically significant in the multivariate regression model (OR 0.56, p < 0.001). Longer duration of PsA was associated with lower probability of achieving MDA both in univariate (OR 0.98, p = 0.027) and multivariate models (OR 0.98, p = 0.012), while BMI was significantly associate only in the univariate model (OR 1.30, p = 0.029). In addition, among MetS components, plasma glucose concentration (> 110 mg / dl) was associated with lower probability of achieving MDA both in univariate analysis (OR 0.48, p = 0.000) and multivariate (OR 0.59, p < 0.001). Instead, waist circumference (OR 0.979, p = 0.000), serum concentrations of HDL-C (OR 1.021, p = 0.000) and triglycerides (OR 0.993, p = 0.000) were significantly associated only in univariate analysis. The presence of metabolic syndrome was found to be associated with a lower probability of achieving MDA in the following domains: tender joint count (OR 0.63, p = 0.015), swollen joint count (OR 0.42, p <0.001), tender entheseal count (OR 0.73, p = 0.007), PASI (Psoriasis Area Severity Index) (OR 0:51, p <0.001) and HAQ (Health Assessment Questionnaire) (OR 0.66, p = 0.015). Conclusions: The results of this study indicate that metabolic syndrome is associated with a lower probability of achieving MDA in PsA patients in therapy with anti-TNF-alpha. Probably a major reason of this result is related to the increased secretion of adipokines. In subjects with metabolic syndrome, these factors contribute to the development of a pro-inflammatory state, increasing the synthesis and the release of pro-inflammatory cytokines, in particular interleukin-6 and TNF-alpha, whose role is well established in the pathogenesis of PsA.