Increasing prevalence of thalassemia in America: Implications for primary care

Abstract

Thalassemia, once a rarity in the United States, is increasingly encountered in clinical practice due to shifts in immigration. Early carrier screening in at-risk populations can help clinicians implement genetic counseling and prevent new cases. Chronic transfusions are the mainstay of therapy for patients with severe thalassemia (beta thalassemia major), and are used intermittently in individuals with milder forms of thalassemia (Hb H/H Constant Spring disease and beta thalassemia intermedia). Iron overload is a major source of morbidity and mortality in individuals with transfusion and non-transfusion-dependent thalassemia, necessitating iron chelation therapy. Iron overload contributes to increased risk of cirrhosis, heart failure, and endocrinopathies, while ineffective erythropoiesis and hemolysis contribute to multiple complications, including splenomegaly, extramedullary hematopoiesis, pulmonary hypertension, and thrombosis. An understanding of the importance of carrier screening, complications, monitoring, and management strategies, coupled with collaboration with a hematologist with thalassemia expertise, is essential to reduce the morbidity and mortality in patients with thalassemia.Key MessagesThalassemia is becoming more prevalent in the United States due to immigration of people from affected regions, with an approximately 7.5% increase over the last five decades.Newborn screening, antenatal screening, prenatal diagnosis, and counseling are key to early diagnosis and prevention of thalassemia.Chronic transfusions are the mainstay of therapy for patients with severe thalassemia and milder forms of thalassemia in some cases, but can lead to iron overload, which has numerous clinical consequences.Iron overload can be effectively monitored by blood tests and magnetic resonance imaging, and be managed with iron chelation to reduce adverse effects on target organs and improve survival.