Are we already decreasing Hereditary Angioedema mortality?

Published: May 4, 2022

Deaths from asphyxia in patients with Hereditary Angioedema (HAE) have been reported since the first descriptions of the disease. Many advances have occurred over the past decades that affect survival and quality of life on treated patients. However, not all patient populations have access to the same diagnosis and treatment resources. Recent studies have pointed out the significant inequalities in HAE provision of services and treatments worldwide.

In order to evaluate HAE mortality in countries with limited diagnosis and treatment resources, Minafra et al. performed a study in a referral center in Brazil. This research was recently published in The Journal of Allergy and Clinical Immunology: In Practice. The researchers evaluated a series of patients with a diagnosis of HAE. These patients were organized in family clusters and the pedigrees were constructed. The authors assessed the family members, the number of patients with HAE (suspected or confirmed diagnosis), and deaths. They used the Verbal Autopsy to investigate suspected cases and deaths. This instrument guides and organizes data from fatalities with undefined causes. After the investigation, the deaths were classified as deaths from laryngeal edema (LE) or from other causes. The authors also analyzed the place of death, the time between the onset of symptoms and death, the life span in different groups of patients, and the medical assistance and treatment received.

The authors encountered 433 patients with symptoms of HAE from 46 different families. Only 197 (41.3%) had a confirmed diagnosis. A total of 75 deaths were evaluated. Only 10 of these 75 patients received the diagnosis of HAE before death, and the HAE diagnosis was made after death in 65 of 75 patients using the verbal autopsy. The final cause of death, after the investigation, was 39/75 (52%) of asphyxia due to LE and 36/75 (48%) of deaths from other causes. Ten of the LE deaths occurred in the last decade. Twenty-three of the 39 patients were hospitalized, and 16/39 (41%) died at home or on the way to the hospital. The time from symptom onset to death was a median of 8 hours. Five of the 39 patients who died from LE had a previous diagnosis of HAE, and all of them used long-term prophylaxis with attenuated androgens. Three patients received Fresh Frozen Plasma but developed asphyxia despite the medication. None of the patients received any medication specific to HAE attacks. Eighteen (46.2%) of the 39 patients received medication without proven effectiveness in treating the HAE crisis. Throat pain/discomfort was the most common symptom experienced by 71.8% of the patients. The most common mistaken diagnosis on the original death certificate was allergy/anaphylaxis. The lifespan of patients who died from LE was reduced by 20 years compared with those who died from other causes.

Patients around the world have access to different diagnostic and treatment resources. A careful look at patients with limited resources shows that high mortality continues to be a reality in middle-income countries’ HAE patients. Asphyxia due to LE was the highest cause of death, accounting for more than half of the cases, even when compared to the sum of all other causes of death in the population studied. Large number of undiagnosed patients makes the situation even more severe, and it is responsible for most deaths.

All HAE patients should have access to confirmatory testing and appropriate treatment, which must be defended to the health authorities. Achieving these results must be a goal of healthcare professionals and patient associations. Public policies directed to the correct diagnosis and access to treatment are indispensable to change the observed scenario.

The Journal of Allergy and Clinical Immunology: In Practice is an official journal of the AAAAI, focusing on practical information for the practicing clinician.

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