HAE OVERVIEW
Hereditary angioedema (HAE) is a rare, debilitating, and potentially life-threatening genetic disease characterized by recurrent attacks of angioedema. HAE is marked by unpredictable and highly variable swelling and is not associated with urticaria or pruritus.1,3
Epidemiology
HAE is a rare disease that affects about 1 in 50,000 people in the entire world.4
Children and adolescents may start to experience the symptoms of swelling at an early age, with increased occurrences and severity after puberty.3
While the frequency and intensity of HAE attacks vary greatly from patient to patient, as many as 78% of patients surveyed in a 2017 study reported an attack within the past month.4
Genetic basis of HAE
HAE is an autosomal dominant disorder, which means that a child of a patient with HAE has a 50% chance of inheriting it.2,3 Approximately 75% of patients with HAE inherited the disease, and 25% of patients have a spontaneous genetic mutation that causes HAE.5 It is recommended that parents, siblings, and children of a patient with HAE should also be tested for HAE.3
Most patients with HAE have an underlying deficiency of functional C1 esterase inhibitor that leads to excess bradykinin production.6,7
Most people with HAE have either type I or type II HAE.2
- Type I is the most common form of HAE, comprising up to 85% of the HAE patient population and characterized by low levels of functional antigenic C1 esterase inhibitor.2
- Type II, which affects the remaining 15% of patients, is characterized by normal antigenic and low functional levels of C1 esterase inhibitor.2
