Haemoglobinopathies and other rare anemias in Spain: ten years of a nationwide registry (REHem-AR)

Abstract

REHem-AR was created in 2013. The progressive implementation of neonatal screening for haemoglobinopathies in Spanish autonomous communities where the registry had not been implemented, as well as the addition of new centres during this period, has considerably increased the sample of patients covered. In this study, we update our previous publication in this area, after a follow-up of more than 5 years. An observational, descriptive, multicentre and ambispective study of adult and paediatric patients with haemoglobinopathies and rare anaemias registered in REHem was performed. The data are from a cross-sectional analysis performed on 1 June, 2023. The study population comprised 1,756 patients, of whom 1,317 had SCD, 214 had thalassaemia and 224 were diagnosed with another condition. Slightly more than one third of SCD patients (37%) were diagnosed based on neonatal bloodspot screening, and the mean age at diagnosis was 2.5 years; 71% of thalassaemia patients were diagnosed based on the presence of anaemia. Vaso-occlusive crisis and acute chest syndrome continue to be the most frequent complications in SCD. HSCT was performed in 83 patients with SCD and in 50 patients with thalassaemia. Since the previous publication, REHem-AR has grown in size by more than 500 cases. SCD and TM are less frequent in Spain than in other European countries, although the data show that rare anaemias are frequent within rare diseases. REHem-AR constitutes an important structure for following the natural history of rare anaemias and enables us to calculate investment needs for current and future treatments.

Keywords: Hemoglobinopathies; Nationwide registry; Rare anaemias.

Fig. 1

Countries of birth of SCD patients (A) and their fathers (B) and mothers (C). Data are expressed as a percentage

Fig. 2

Incidence of the most frequent complications secondary to sickle cell disease (SCD) since our last publication in 2017. Data are expressed as a percentage over the total number of patients with SCD in follow-up that year. Vaso-occlusive crises were defined at the discretion of each investigator (they have been homogeneously defined in the registry subsequent to this analysis). Kidney disease includes proteinuria, kidney failure and nocturnal enuresis. Lung disease includes restrictive disease, obstructive disease (asthma), mixed disease, hypoxaemia and sleep apnoea-hypopnoea syndrome. Neurological complications include cerebrovascular accident (CVA) and neurocognitive abnormalities other than the sequelae of symptomatic CVA. Liver disease includes haemosiderosis or viral hepatitis. *Onset of chronic complications (e.g. nephropathy, biliary lithiasis) during the year in question. Not included if already present

Fig. 3

Kaplan–Meier curves. Overall survival in sickle cell disease and thalassaemia

Fig. 4

Most frequent countries of birth of thalassaemia patients (D), their fathers (E) and their mothers (F)

Fig. 5

Incidence of the most frequent complications secondary to thalassaemia, annually since 2018. Data are expressed as a percentage. Hepatopathy includes viral hepatitis, haemosiderosis and drug toxicity

Fig. 6

Number of patients registered per year since the registry was created in 2013