Surveillance of Bleeding Disorders, Texas, 2007

BackgroundIn 2007, some 1261 patients with hemophilia or other bleeding disorders were seen at federally funded hemophilia treatment centers (HTCs) in Texas. Although HTCs function as sites for passive surveillance of bleeding disorders, annual HTC visit data likely underestimate true prevalence of the disease due to the infrequent nature of healthcare utilization for this population.PurposeThe main aim of this study was to compare two alternative methods for estimating prevalence of hemophilia and to describe the challenges associated with making valid prevalence estimates. Each method utilized a separate data source, with the goal of validating one or both of the methods, compared to the gold standard of active case finding.MethodsTwo data sets, one describing treatment of hemophilia in an outpatient setting at HTCs and one describing treatment and care of patients in a hospital inpatient setting, were used to calculate annual prevalence estimates of hemophilia among men in Texas in 2007. The prevalence estimates resulting from each of the two methods were compared to each other and to past estimates based on active surveillance.ResultsCalculations based on HTC data resulted in estimated prevalence rates of 8.9 and 2.1/100,000 male population for hemophilia A and B, respectively. Prevalence estimates based on hospital discharge data yielded rates of 12.3 and 2.9/100,000 males for hemophilia A and B, respectively.ConclusionsHemophilia is a rare, chronic disease with high treatment costs. Prevalence estimates based on HTC and hospital discharge data were similar to each other as well as to active surveillance prevalence estimates in published literature.