Hereditary angioedema: a prospective study of a Brazilian single‐center cohort

A real-world study of hereditary angioedema patients due to C1 inhibitor deficiency treated with danazol in the Brazilian Public Health System

Introduction

Hereditary angioedema (HAE) due to C1 inhibitor (C1-INH) deficiency is an ultra-rare autosomal dominant inherited disease that affects 1 in 67,000 people in the world. The attacks are based on subcutaneous and submucosal edema that can lead to death if not properly managed. Considering the lack of information on the clinical management of Brazilian patients with HAE, this study aimed to identify and characterize patients with HAE-C1-INH that used danazol prophylactic treatment in the Brazilian Public Health System (SUS) and the healthcare resource utilization (HCRU).

Methods

This was an observational retrospective database study with patients treated with danazol from January 2011 until December 2021 within the SUS. The HAE cohort included patients with 12 years or older with at least one record for ICD-10 D84.1, one claim for danazol record, and at least 6 months of available history in the database.

Results

Our study included 799 patients treated in the SUS, with a mean (SD) age at danazol initiation of 40 years (16). The number of patients with HAE showed a similar distribution over this 10-year period analyzed with the highest number of patients in 2015 (n = 509) and 2016 (n = 480). A total of 253 (32%) patients had a record of at least one attack. Of those, 45 (17.8%) had at least one procedure HAE-related hospital admission, and 128 (50.6%) had at least one HAE-related hospital admission. The mean (SD) hospitalization length of stay was 5 (8) days. Over 14% (n = 36) of HAE patients with attack (n = 253) had at least one HAE-related ICU admission.

Conclusion

This database study is the strategy used to allow us to find and describe the characteristics of patients with HAE who use danazol for long-term prophylaxis in the SUS and identify HCRU outcomes of interest such as hospitalizations, inpatient, and outpatient settings. The high rate of attacks, hospitalizations, and general resource uses highlights the necessity to increase awareness of new strategies and accurate approaches to treat HAE patients. Therefore, our findings are important indicators that our health system and guidelines need to be revised and improved to properly diagnose, treat, and assist patients with HAE.

Epidemiology, economic, and humanistic burden of hereditary angioedema: a systematic review

BACKGROUND

This systematic study aims to assess the global epidemiologic, economic, and humanistic burden of illness associated with all types of hereditary angioedema.

METHODS

A systematic search for articles reporting the epidemiologic, economic, and humanistic burden associated with patients with HAE was conducted using English and Chinese literature databases from the inception to May 23, 2022. The selected studies were assessed for their quality and risk of bias. The study was conducted in accordance with Preferred Reporting Items for Systematic Reviews and Meta-Analyses and registered with the International Prospective Register of Systematic Reviews (PROSPERO; CRD42022352377).

RESULTS

In total, 65 articles that met the search inclusion criteria reported 10,310 patients with HAE, of whom 5861 were female patients. Altogether, 4312 patients (81%) and 479 patients (9%) had type 1 and type 2 HAE, respectively, whereas 422 patients (8%) had HAE-normal C1-INH. The overall prevalence of all types of HAE was between 0.13 and 1.6 cases per 100,000. The mean or median delay from the first onset of a symptom of HAE to confirmed diagnosis ranged from 3.9 to 26 years. The estimated risk of death from asphyxiation was 8.6% for patients with HAE. Hospitalization, medication, unnecessary surgeries, doctor visits, specialist services, and nursing costs are direct expenses that contribute to the growing economic burden. The indirect cost accounted mostly due to missing work ($3402/year) and loss of productivity ($5750/year). Furthermore, impairment of QoL as reported by patient-reported outcomes was observed. QoL measures identified depression, anxiety, and stress to be the most common symptoms for adult patients and children.

CONCLUSION

This study highlights the importance of early diagnosis and the need for improving awareness among health care professionals to reduce the burden of HAE on patients and society.

The analysis of the effect of the COVID-19 pandemic on patients with hereditary angioedema type I and type II

Due to the similarity between the pathomechanism of SARS-CoV-2 infections and hereditary angioedema due to C1-inhibitor deficiency (C1-INH-HAE), a possibility emerged that C1-INH-HAE may worsen the course of the infection, or that the infection may influence the severity of angioedema (HAE) attacks in C1-INH-HAE patients. Our study aimed to evaluate the effects of the COVID-19 pandemic on the quality of life (QoL) of Hungarian C1-INH-HAE patients, and to survey the acute course of the infection, post COVID symptoms (PCS), vaccination coverage and the side effects of vaccines in this patient population. 93 patients completed our questionnaire between 1st July 2021 and 31st October 2021. In this same period and between March 2019 and March 2020, 63 patients completed the angioedema quality of life questionnaire (AE-QoL). Out of those patients infected with SARS-CoV-2 in the examined period (18/93 patients; 19%), 5% required hospitalization, 28% experienced HAE attacks in the acute phase of the infection, and 44% experienced PCS. A total number of 142 doses of vaccines were administered to the patients. Serious vaccine reactions did not occur in any case, 4 (5%) out of the 73 vaccinated patients experienced HAE attacks. No significant difference (p = 0.59) was found in the median of the AE-QoL total score, or in the number of HAE attacks prior and during the pandemic. Based on our study, HAE patients did not experience more serious SARS-CoV-2 infection, and it did not aggravate the course of HAE either. Changes in the QoL were not significant, and vaccines were safe in HAE patients.

Real-world experience of hereditary angioedema (HAE) in Mexico: A mixed-methods approach to describe epidemiology, diagnosis, and treatment patterns

Introduction and objectives

Due to the lack of structured and systematic information available, the aim of this study was to describe the epidemiology, diagnosis, healthcare processes, and treatment patterns of hereditary angioedema (HAE) in Mexico. To achieve this, different data sources were consulted regarding medical literature, structured health system databases, and angioedema-specialized physicians (AEP) opinion regarding HAE.

Material and methods

A mixed methods approach was conducted in 4 phases: I) systematic literature review (SLR) and meta-analysis according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines; II) review of national health system (NHS) databases and systematic reports; III) physician survey; and IV) an epidemiologic model. ICD 10 D84.1 encoded records from the NHS were used to estimate the number of patients with HAE attended and treated during 2019. A survey was implemented to increase understanding of the clinical profile and treatments used.

Results

A prevalence rate of 0.9/50 000 inhabitants was estimated for 2019. In the same year, an estimated 317 HAE type 1 patients were recorded in the NHS, aged ≥11 years old. The most frequent clinical symptoms were cutaneous edema (67.5%) and abdominal pain (47.9%). A severe episode with laryngeal edema appeared in 27.5% of cases. Acute episodes were mainly moderate to severe (77.0%), with an annual per capita frequency of emergency visits of 7.6 patient-year (range 1-12/patient-year). The main reasons for hospitalization corresponded to laryngeal facial, tongue, and abdominal edemas, representing 73.3% of annual ICD 10 D84.1 reported hospitalizations. The main treatments that patients with HAE received were fresh frozen plasma for acute attacks and danazol for short-term prophylaxis (STP).

Conclusions

Despite efforts to make HAE visible, according to this study, cases recognized and treated in the NHS represent only 16.6% of the estimated prevalence.

National survey on clinical and genetic characteristics of patients with hereditary angioedema in Latvia

BACKGROUND

Hereditary angioedema (HAE) is a rare and life-threatening inborn error of immunity. HAE is mostly caused by pathogenic variations in the serine protease inhibitor gene 1 (SERPING1), leading to deficient or dysfunctional C1-inhibitor (C1-INH), overproduction of bradykinin, and development of recurrent subcutaneous and/or submucosal oedema. The prevalence of HAE is 1 in 50,000 - 100000 people worldwide. We aimed to describe the clinical features and genetic spectrum of hereditary angioedema with C1-INH deficiency (C1-INH-HAE) in Latvia.

METHODS

All patients from Latvia diagnosed with HAE (types I/II) from 2006 to March 2022 were included in the study. Laboratory tests and clinical data were analysed, and genetic tests with Sanger sequencing and whole genome sequencing were performed.

RESULTS

The study identified 10 C1-INH-HAE patients (nine females, one male) from eight families. The point prevalence of HAE in Latvia is 0.53 per 100 000 inhabitants. Of all patients, seven (70%) had HAE type I and three (30%) had HAE type II. The median age of patients was 54 years and the median age at onset of symptoms was 15 years. A significant delay (median 20.5 years) until diagnosis was observed, and 60% of patients had a positive family history of angioedema. All HAE patients have been hospitalised a median two times during their lifetime. Skin (100%), abdominal (80%), and airway (80%) oedema were the most frequent symptoms. Triggering factors (60%) and prodromal symptoms (90%) were referred. Attacks were severe in 50% of patients, moderate in 10%, and mild in 40%. Pathogenic variations of SERPING1 were identified in eight patients (six families), confirming the diagnosis molecularly. In two patients (two families), no pathogenic variations in the genes were found even after whole genome sequencing.

CONCLUSIONS

Current data shows a significant delay and clear underdiagnosis of HAE in Latvia. Higher awareness and better information and communication between doctors would improve the diagnosis and management of HAE; as would screening of family members, patients with recurrent angioedema unresponsive to antihistamines and glucocorticoids, and patients with recurrent episodes of severe, unexplained abdominal pain.

Consider Hereditary Angioedema in the Differential Diagnosis for Unexplained Recurring Abdominal Pain

Health care providers are likely to encounter patients with recurrent unexplained abdominal pain. Because hereditary angioedema (HAE) is a rare disease, it may not be part of the differential diagnosis, especially for patients who do not have concurrent skin swelling in addition to abdominal symptoms. Abdominal pain is very common in patients with HAE, occurring in up to 93% of patients, with recurrent abdominal pain reported in up to 80% of patients. In 49% of HAE attacks with abdominal symptoms, isolated abdominal pain was the only symptom. Other abdominal symptoms that commonly present in patients with HAE include distension, cramping, nausea, vomiting, and diarrhea. The average time from onset of symptoms to diagnosis is 6 to 23 years. Under-recognition of HAE in patients presenting with predominant gastrointestinal symptoms is a key factor contributing to the delay in diagnosis, increasing the likelihood of unnecessary or exploratory surgeries or procedures and the potential risk of related complications. HAE should be considered in the differential diagnosis for patients with unexplained abdominal pain, nausea, vomiting, and/or diarrhea who have complete resolution of symptoms between episodes. As highly effective targeted therapies for HAE exist, recognition and diagnosis of HAE in patients presenting with isolated abdominal pain may significantly improve morbidity and mortality for these individuals.

Icatibant use in Brazilian patients with hereditary angioedema (HAE) type 1 or 2 and HAE with normal C1-INH levels: findings from the Icatibant Outcome Survey Registry Study

BACKGROUND

Hereditary angioedema can be caused by C1-Inhibitor (C1-INH) deficiency and/or dysfunction (HAE-1/2) or can occur in patients with normal C1-INH (HAE nC1-INH).

METHODS

The Icatibant Outcome Survey (IOS; NCT01034969) registry monitors the safety and effectiveness of icatibant for treating acute angioedema.

OBJECTIVE

Present findings from Brazilian patients with HAE-1/2 and HAE nC1-INH participating in IOS.

RESULTS

42 patients were enrolled (HAE-1/2, n = 26; HAE nC1-INH, n = 16). Median age at symptom onset was significantly lower with HAE-1/2 vs. HAE nC1-INH (10.0 vs. 16.5y, respectively; p = 0.0105), whereas median age at diagnosis (31.1 vs. 40.9y; p = 0.1276) and the median time between symptom onset and diagnosis (15.0 vs. 23.8y; p = 0.6680) were numerically lower vs. HAE nC1-INH, respectively. One icatibant dose was used for > 95% of HAE attacks. Median (range) time-to-event outcomes were shorter for patients with HAE nC1-INH vs. HAE-1/2, including time to first administration (0.5 [0-96.0] vs. 1.0 [0-94.0]h, respectively), time from first administration to complete resolution (1.0 [0-88.0] vs. 5.5 [0-96.0]h, respectively), and total attack duration (7.0 [0.3-99.0] vs. 18.5 [0.1-100.0]h, respectively). Mean (SD) time from attack onset to resolution was significantly shorter for patients with HAE nC1-INH vs. HAE-1/2 (9.8 [18.7] vs. 19.6 [24.0]h, respectively; p = 0.0174). 83 adverse events (AEs) in 42 patients were reported; most were mild (66.3%) or moderate (13.3%) and non-serious (75.9%). The most common icatibant-related AE was injection site erythema (HAE-1/2, 34.6%; HAE nC1-INH, 18.8%).

STUDY LIMITATIONS

This was an observational study without a treatment comparator and that relied on patient recall.

CONCLUSIONS

Findings demonstrate effectiveness and tolerability of icatibant in Brazilian HAE patients.

Hereditary angioedema: Report of the dental treatment of 12 Brazilian patients

OBJECTIVE

The aim of this study was to report on clinical experience in Brazil in the dental treatment and the oral conditions of a group of patients with hereditary angioedema (HAE).

STUDY DESIGN

The study analyzed demographic data, type of HAE, intensity of attacks, long-term and short-term prophylaxis, dental procedures, and occurrence of crises after the procedures were performed. Radiographic evaluation of the number of teeth and bone loss was also performed.

RESULTS

Data from 12 patients were collected; most were women, presenting with C1-INH-HAE type I and a history of severe attacks. All patients reported use of regular medications (long-term prophylaxis), mostly attenuated androgens, to prevent/attenuate HAE attacks. These patients had several missing teeth and alveolar bone loss. Tooth extraction was the most common procedure. In half the patients, the procedures had been performed without modification in long-term prophylaxis. The others were treated with an additional prophylaxis protocol (short-term prophylaxis), particularly those who underwent tooth extraction. None of the study patients developed HAE attacks after dental procedures.

CONCLUSION

The occurrence and intensity of a possible HAE attack after dental procedures are unpredictable, but with careful preliminary screening by dental and immunology teams and the use of therapeutic prophylaxis, the risk could be minimized.