Clinical and Economic Burden of Transfusion-Dependent β-Thalassemia in Adult Patients in the United States

Abstract

Introduction: β-thalassemia is a genetic blood disorder in which defective β-globin synthesis leads to ineffective erythropoiesis. Patients with transfusion-dependent β-thalassemia require lifelong management with blood transfusions and iron chelation therapy. Complications related to iron overload can cause significant morbidity and mortality, and it is well understood that the chronic management of this disease presents a substantial burden to patients in terms of healthcare visits and costs. However, the specific clinical and economic burden has not been well characterized in the USA.Objectives: The objectives of this study were to analyze the clinical and economic burden of current disease management for patients with transfusion-dependent (TD) β-thalassemia in the USA over a 1-year time period.Methods: This retrospective matched cohort study was conducted using the Truven Health MarketScan® Research Databases (Truven Health Analytics, Ann Arbor, MI). The MarketScan® Databases provide detailed utilization, outcomes, and cost data for healthcare services performed in inpatient and outpatient settings, and contains de-identified data from > 110 million patient lives. Adult patients with TD β-thalassemia and matched controls were identified between Jan 1, 2011 and Sep 30, 2015. Patients were required to be ≥ 18 years old at the index date with ≥ 12 months of continuous enrollment post index date. TD β-thalassemia patients were required to have ≥ 2 claims with a β-thalassemia (ICD-9-CM 282.44, ICD-10-CM D56.1) or hemoglobin E-β thalassemia (ICD-9-CM 282.47, ICD-10-CM D56.5) diagnosis, and ≥ 8 transfusion events to be defined as TD. Patients were excluded if they had ≥ 2 claims with any sickle cell diagnosis. Controls were required to have ≥ 1 medical claim and were excluded if they had a diagnosis of any thalassemia or sickle cell condition. Patients with TD β-thalassemia were matched to controls in a 1:5 ratio using exact matching based on age, sex, index year, payer type, and census division. Comorbidities were not used in matching because patients with TD β-thalassemia have a high burden of disease-associated comorbidities. Index date was the first claim for a β-thalassemia diagnosis in patients with TD β-thalassemia or the first medical claim for controls. Outcomes examined were disease burden such as comorbid conditions, healthcare utilization and costs specific to the management of TD β-thalassemia, as well as general healthcare utilization and costs during the 12 months post index date. Chi-squared tests and Fisher's exact test were used for categorical variables and the Wilcoxon-Mann-Whitney test was used for continuous outcomes.Results: Fifty patients with TD β-thalassemia met selection criteria and were matched to 250 controls. Mean age was 34.7 ± 9.1 years for both patients and controls. Patients with TD β-thalassemia had higher rates of diabetes (18% vs 6%, P = 0.009), cardiac disease (30% vs 2%, P < 0.001), hypogonadism (22% vs 7%, P = 0.002), osteoporosis (16% vs 1%, P < 0.001), and hypothyroidism (12% vs 4%, P = 0.045) compared with controls. On average, patients with TD β-thalassemia required 17 transfusions per year, 23 days apart. Mean number of outpatient visits was significantly higher in the TD β-thalassemia cohort compared with matched controls; however, inpatient and ER visits were not significantly different (Table 1). Mean total healthcare costs among the TD β-thalassemia cohort were USD 128,062 ± 62,260, compared with USD 5,438 ± 11,855 in controls (P < 0.001). Medical and medication costs were significantly higher in the TD β-thalassemia cohort compared with matched controls (Table 2). Among patients with TD β-thalassemia, total costs were primarily driven by chelation and transfusion costs, with other costs displayed in the figure. The majority of patients with TD β-thalassemia received oral chelators (72%), whereas 30% of patients received injectable chelators; 14% of patients received both oral and injectable chelators.Conclusions: Ongoing comprehensive treatment for TD β-thalassemia poses a substantial clinical and economic burden as compared with matched controls. Patients with TD β-thalassemia had significantly higher healthcare resource utilization, medication costs, and total costs compared with matched controls, and required frequent visits to their healthcare provider, which poses a burden to their quality of life and work productivity. [Display omitted] DisclosuresSheth:Novartis, Celgene, ApoPharma, Bluebird Bio: Consultancy. Weiss:Celgene: Employment; Zocdoc: Other: Equity ownership (options have not vested yet); Zocdoc: Other: Husband's employment. Parisi:Celgene: Employment, Equity Ownership. Ni:Celgene: Employment.