CRP and psoriatic arthritis: BMI: body mass index, BSA: Body surface area, CASPAR: Classification criteria for psoriatic arthritis, CRP: C-reactive protein, DLQI: dermatology life quality index, DMARDS: disease-modifying antirheumatic drugs, ESR: erythrocyte sedimentation rate, Kcal: kilocalorie, LDL: low density lipoprotein, LED: low energy diet, MTX: methotrexate, PASI: psoriasis area and severity index, RCT: randomized clinical trial, SHD: standard hospital diet, TNF: tumor necrosis factor, VAS: visual analogue scale for pain.