NHLBI Recipient Epidemiology Donor Evaluation Study (REDS)-III - Brazil Sickle Cell Disease Cohort (REDS-BSCDC)

The Recipient Epidemiology and Donor Evaluation Study (REDS)-III program established a Brazilian Sickle Cell Disease (SCD) Cohort to identify molecular determinants of response to transfusions, alloimmunization and risk factors associated with HIV infection. The Brazil population presents a complex admixture of African, European, Asian and Indigenous heritage and will provide insights into genetic, demographic, social, and healthcare system determinates of SCD outcomes. The REDS-III Brazil SCD cohort began in the Fall of 2013 and aimed to: Establish a cohort of SCD patients with a comprehensive centralized electronic database of detailed clinical, laboratory and transfusion information, as well as establish a repository of blood samples to support biological studies relevant to SCD pathogenesis and transfusion complications; Characterize changes in markers of inflammation in response to transfusion by analyzing chemokine/cytokine panels in serial post transfusion specimens; Identify single nucleotide polymorphisms (SNPs) that contribute to the risk of red blood cell alloimmunization in SCD by performing a genome-wide association (GWA) study in transfused SCD patients; Characterize risk of HIV and HIV outcomes in the Brazilian SCD population and compare SCD outcomes among HIV sero-positive and sero-negative SCD patients. ]]>
Inclusion Criteria Adult (≥18 years of age) and pediatric patients (<18 years) with a confirmed diagnosis of sickle cell disease who are currently active patients at the REDS-III hemocenters. Potential participants in the REDS-III Brazil SCD cohort were randomly sampled from each hemocentre's active patient population. Randomly selected participants were recruited at routine medical care visits. A total of 2,795 subjects from the six participating Brazilian centres were enrolled from November 2013 through March 2015. From the random sample lists, the proportion of participants who were approached, recruited and consented ranged by site from 88 - 99%. Enrolled subjects have had approximately annual study visits to capture demographic information and key SCD and transfusion outcomes through an interview and an extensive abstraction of the complete medical record. Exclusion Criteria Lack of confirmed clinical SCD diagnosis.]]>
The REDS-III SCD cohort study is a collaboration between American investigators at Blood Systems Research Institute, San Francisco, California, and Brazilian investigators at four haemocenters (blood donation and transfusion centers which provide outpatient care to haematology patients). Six patient care sites are included: (i) Fundação Hemominas in the three cities of Belo Horizonte (HBH), Juiz de Fora (JFO) and Montes Claros (MOC) in the state of Minas Gerais, (ii)Fundação Hemorio in Rio de Janeiro in the state of Rio de Janeiro, (iii) Fundação Hemope in Recife in the state of Pernambuco and, (iv) Instituto da Criancxa, Hospital das Clinicasda Faculdade de Medicina da Universidade de São Paulo (HCFMUSP) in São Paulo in the state of São Paulo. A list of the 9676 active patients (patients with at least one clinical encounter in the last 3 years) at the six participating sites was created and a random sample from this list was selected by RTI. Approximately 50% of the active patient population (4956 of 9676) was enlisted as the sample frame in order to achieve a recruitment goal of 3000 participants. Randomization was conducted in strata proportional to the age (children defined as aged <18 years or adults defined asaged ≥18 years), gender and SCD genotype distributions of the patients at each hemocenter to ensure the study population was reflective of the SCD population at each site. Patients randomly selected as eligible were recruited at scheduled clinic visits. An interview, medical record abstraction and blood collection were performed for all consenting participants. The interview captured comprehensive demographics and vital signs were measured. Race was defined according to the standards of the Brazilian census, which refers to skin color instead of heritage. Medical records were reviewed by hematologists, or research nurses under the supervision of hematologists, to abstract clinical data using standardized definitions of the phenotypic manifestations of SCD. Abstraction included any documentation in the patient's record of specific clinical events, such as stroke, a vascular necrosis, priapism, leg ulcers, bacteremia and other SCD complications which had occurred during patients' lifetime. Detailed information related to hospitalizations, transfusions, laboratory testing and screening examinations that occurred in the year prior to enrolment was also abstracted (summary of collected data in Table SI). Transfusion history and blood bank data, including red blood cell phenotype and antibody data, were extracted from each haemocentre's records. A comprehensive electronic database was created to centralise all clinical, laboratory and transfusion information. This dataset presents the baseline data collected during enrolment visits in 2013-2015.]]>