Objective: Investigation of the impact on survival of inflammatory parameters (C-reactive protein, ESR), markers of immune activation (serum soluble IL-2 receptor, soluble CD30), and N-terminal propeptide of type III procollagen levels (PIIINP) in systemic sclerosis (SSc).
Methods: In a prospective follow up study, clinical and laboratory data of 80 patients with SSc were evaluated. Kaplan-Meier survival curves and Cox proportional hazards model were used. Eighty cases with SSc were evaluated. Female/male ratio was 8/72. The mean (+/-SD) age was 49.3 (+/-12.3) years, 16 patients died during our mean follow up of 58.1 months.
Results: In the univariate analysis, the presence of a C-reactive protein level above 20 mg/l was an unfavourable prognostic sign (p<0.001). Increased level of PIIINP level also caused an unfavourable outcome of disease (p<0.001). Conversely, increased ESR, soluble IL-2 receptor, soluble CD30 levels, presence of anaemia, did not influence the prognosis. Male gender (p<0.005), diffuse cutaneous SSc, clinically significant lung involvement (p<0.001), kidney (p<0.0001), cardiac (p<0.05) manifestations including pericarditis (p<0.02) were unfavourable prognostic signs by univariate Kaplan-Meier method. Multivariate analysis by Cox proportional hazards model showed that the increased level of PIIINP (RR: 6.98), and presence of diffuse cutaneous SSc (RR: 5.14) were independent unfavourable prognostic signs.
Conclusions: An increased collagen metabolism unfavourably influences the outcome of SSc. This parameter may also be a potential candidate as a disease activity marker.