HYPOCHROMIC ERYTHROCYTES AS PROGNOSTIC INDICATOR OF SURVIVAL AMONG PATIENTS WITH SYSTEMIC SCLEROSIS SCREENED FOR PULMONARY HYPERTENSION

Background: Iron deficiency is frequent among patients with systemic sclerosis (SSc), particularly among those with pulmonary hypertension (PH). First data indicate prognostic importance of hypochromic erythrocytes (HypoHe) ≥2% among patients with PH. Hence, the aim of this study was to investigate the predictive value of HypoHe in SSc patients screened for PH. Methods: In this retrospective, single-center cohort study SSc patients screened for PH were included. Clinical characteristics, laboratory and pulmonary functional parameters associated with the prognosis of SSc were analysed using uni- and multivariable analysis. Results: A total of 280 SSc patients were screened, 171 were included in the analysis having complete data of iron metabolism (79% female, 61.0±12.9 years of age, 73.2% limited cutaneous SSc, 56 manifest PH and 112 pulmonary fibrosis). The patients were followed for 2.4±1.8 (median 2.4) years. HypoHe ≥2% at baseline was significantly associated with worse survival in the uni- (p=0.018) and multivariable analysis (p<0.0001). Overall 34.5% of the patients suffered from iron deficiency and 22% received iron substitution during follow-up. HypoHe ≥2% was identified as an independent predictor of mortality for patients with and without pulmonary manifestations of SSc. Conclusions: This study detected for the first time that HypoHe ≥2% is an independent prognostic predictor and can possibly be used as a biomarker among SSc patients. Further studies are needed to confirm these results.