When is prophylaxis for hereditary angioedema necessary?

Objective: To determine when newer agents, such as C1 esterase inhibitor protein (C1-INH), should be considered as prophylaxis to decrease hereditary angioedema (HAE) attacks as an alternative to androgens, which have significant adverse events.

Data Sources: A literature review (PubMed, Google, and Ovid), guideline review, expert panel meeting, and group discussion were performed to decide when prophylaxis is indicated.

Study Selection: Articles addressing HAE therapy published in the peer-reviewed literature were selected.

Results: The retrieved studies demonstrate that C1-INH is effective and that the half-life makes it attractive for prophylactic use. The short half-lives of ecallantide, icatibant, and recombinant human C1-INH limit their use as prophylactic agents. Patients with severe anxiety, more than 1 attack per month, rapid progression of attacks, limited access to health care, more than 10 days lost from work or school per year, previous laryngeal swelling, more than 3 emergency department visits per year, more than 1 hospitalization per year, previous intubation, previous intensive care unit care, significant compromise in quality of life, or narcotic dependency should be considered for androgen or C1-INH prophylaxis therapy.

Conclusion: Patients with HAE with frequent attacks, severe attacks, past laryngeal attacks, excessive loss of work or school, significant anxiety, and poor quality of life should be considered for C1-INH prophylaxis, especially those who fail, are intolerant of, have adverse reactions to, or are not candidates for androgen therapy.