Background As a result of immune complex reactions the endothelium damage is observed in patients with polyarthicular JIA (pJIA). It causes not only clinical signs of the disease but also leads to damages of vital internals, dyslipidemia and other metabolic disorders, hemostasis disorders. These abnormalities contribute to comorbidities which aggravate disease course, decrease treatment response, worsen prognosis and quality of life.
Objectives To study pJIA-related changes of the cardiovascular, renal and hepatic functions in the affected children.
Methods This was a prospective cohort study enrolling patients with pJIA. Their cardiovascular system was assessed by ECG, PD-ultrasound and routine arterial blood pressure monitoring. The rate of glomerular filtration, serum creatinine level, serum ALT and AST activity, lipid profile and other specific tests were used to study renal and hepatic functions. Charlson Comorbidity Index (CCI) for children was calculated. It's correlation with various factors have been assessed by regression analysis. Descriptive statistics data are presented as mean ± SD.
Results 118 patients with JIA (78 females) were enrolled. Mean age was 10.27±0.39 years, mean disease duration 132.35±5.26 months. Mean number of affected joints was 6.04±0.3. All patients were treated with NSAIDs. 95.7% patients received MTX, 15.3% MTX+SSZ. 19.5% of patients were treated with GC incl. 5.1% as a puls-therapy. Cardiovascular abnormalities were found in 65.3%, mainly on ECG (low voltage, affected repolarization). 4.2% patients had decreased heart contractility and 1.9% dilated heart compartments. Increased levels of cholesterol were found in 12.8%, β-lipoproteids – in 41.7%. High ALT and AST activity levels were observed in 2.6% and 1.3% of patients accordingly. 19.2% of patients had renal filtration abnormalities: 10.9% low glomerular filtration; 8.3% hyperfiltration. 1.9% had increased serum creatinine level and 2.6% had proteinuria. Total mean CCI was 0.78±0.06. In children with disease duration ≤1 year mean CCI was 0.90±0.28. The highest mean CCI (1.00±0.17) was observed in patients with disease duration 1≤2 years without any significant changes up to 3 (0.86±0.1) and 5 years (0.77±0.08) of observation. In children with disease duration ≤3 years CCI significantly (p<0.05) correlated with age at disease onset, disease activity, disease duration, duration of MTX and GC treatment.
Conclusions Our results show that comorbidities in children with pJIA exist already on the initial stages of disease course and persist in future despite treatment. Organ protectors and immune complex inflammation inhibitors (biologic treatment agents) should be a part of treatment program in this category of patients.
Disclosure of Interest None declared