We conduct a prospective study in order to determine kidney impairment (CKDEPI-GFR and spot urine albumin indexed to creatinine, UACR) among a psoriatic out-patients population.
The study is approved by the Ethics Committee of our Hospital. We use psoriasis area and severity index (PASI) used to asses the severity and extent of psoriasis. Urinary albumin concentration is determined by turbidimetric-immunoassay. The Student’s t-test and Chi squared tests are used to compare continuous and categorical data, respectively. A two-sided p-value<0.05 is considered statistically significant.
219 patients participate in the study. Demographic and clinical charactheristics are reported in Table 1. 39,27% is comorbidities-free (diabetes, hypertension, ictus, smoke, previous nephrotoxic drugs). Prevalence of microalbuminuria (MA) in this group is12.79%.The group with AUCR >30mg/gr-creat shows longer duration’s psoriasis (33,45 ± 11,74 years vs 13,90 ± 11,09 years, p<0.0001, see Graphic 1), and a high prevalence of arthritis. Average serum IgA are higher in patients with AUCR >30mg/gr-creat (IgA 377,40 ± 92,77 mg/dl vs 239,50 ± 80,13mg/dl, p=0,004). Average MA in patients with psoriatic arthritis is significantly higher in comparison patients arthritis-free (50,53 ± 80,44 vs 9,10 ± 13,56 mg/g-urine creat; p= 0,01, see Graphics 2) with comparable eGFR. We performe forward linear regression analysis: MA correlates with presence of arthritis (p<0,0001), disease duration (p<0.0001) and actual PASI (p<0,001). Patients with psoriatic arthritis and MA have higher duration disease; we performe ROC analysis between the outcome and disease time to determine a "cut-off presentation time" for MA. Disease time of ≥21 years is a cut off value (sensibility 88,9%, specificity 83,3% for MA).
Duration of disease and psoriatic arthritis have a strong association with MA, independently. Therefore, patients with psoriatic arthritis, expecially with duration disease longer 21 years, can be routinely screened for MA for a more comprehensive management.
