The US Hereditary Angioedema Association Scientific Registry: hereditary angioedema demographics, disease severity, and comorbidities.

BACKGROUND: Hereditary angioedema (HAE) and idiopathic nonhistaminergic angioedema (INHA) are ultra-rare diseases whose natural histories and comorbidities are incompletely understood. OBJECTIVE: To develop a national patient-centric registry to address these deficiencies in our knowledge and improve our ability to assess the real-world impact of therapeutic interventions. METHODS: Data from members of the US HAE Association were collected into an online registry between 2009 and April 7, 2021. Cohorts were categorized by reported physician diagnosis. Patient reported data were collected using a series of questionnaires. Demographic, natural history, and family history outcomes of the HAE due to C1 inhibitor deficiency (HAE-C1INH) participants were compared with those of the combined HAE with normal C1 inhibitor (HAE-nl-C1INH) plus INHA group. The prevalence of comorbid conditions in the HAE-C1INH group was compared with the general US population. RESULTS: A total of 485 HAE-C1INH, 26 HAE-nl-C1INH, and 70 INHA participants were included in the analysis. Delay to diagnosis was shorter in HAE-C1INH (5 vs 11 years), but both had decreasing delays over time. Differences in attack frequency and location were found between the groups. Morbidity surrogates including emergency department visits, hospitalizations, unnecessary abdominal surgeries, and intubations were strikingly high as was mortality with 36.9% of HAE-C1INH and 15.4% of HAE-nl-C1INH participants reporting family members who died from a HAE attack. Females with HAE-C1INH had a significant increase in the prevalence of depression, sleep disorders, kidney disease, anemia, and hepatitis. Cardiovascular comorbidities were significantly reduced in the HAE-C1INH group. CONCLUSION: The US HAEA Scientific Registry provides a mechanism to enhance our knowledge of HAE and INHA.

A cross-sectional questionnaire assessing patient and physician use of short-term prophylaxis for hereditary angioedema.

BACKGROUND: Current guidelines recommend short-term prophylaxis (STP) before invasive procedures to prevent hereditary angioedema (HAE) attacks; however, adherence to these guidelines may be variable because this indication lacks Food and Drug Administration approval in the United States. OBJECTIVE: To ascertain the STP experiences of patients with HAE and HAE-treating physicians. METHODS: Online questionnaires focusing on STP experiences were distributed by the US Hereditary Angioedema Association to the first 250 patients with HAE and to registered HAE-treating physicians. SAS 9.3 was used to perform descriptive statistics and to test the difference between patients who underwent procedures and those who did not using Pearson χ(2) test, Fisher exact test, and 2-sample t test. RESULTS: For the patient survey, 219 respondents met the criteria for HAE type 1 and 2; 37 (17%) underwent 66 invasive procedures, and all reported receiving STP. Eight patients (22%) reported failed STP, but only 3 required on-demand therapy. For STP, anabolic steroids and plasma-derived C1 inhibitor were the most and second-most commonly used, respectively. For the physician survey, 37 physicians reported caring for 433 patients with HAE. Depending on the procedure, 19% to 54% of physicians used STP and 30% to 86% prescribed on-demand therapy; 69% and 78% of physicians prescribed plasma-derived C1 inhibitor as STP for minimally invasive and invasive procedures, respectively. Physicians reported excellent efficacy for the STP treatments used. CONCLUSION: Physicians reported excellent outcomes using primarily newer STP therapies, namely plasma-derived C1 inhibitor, which was discordant to patient-reported outcomes using older STP therapies, namely anabolic steroids. Well-controlled STP studies are needed to clarify use for patients with HAE in the United States.