Fran Lowry

November 14, 2012

ANAHEIM, California — Despite international guidelines recommending on-demand medicines for at-home attacks in patients with hereditary angioedema (HAE), very few physicians are prescribing such therapy, according to a study presented here at the American College of Allergy, Asthma & Immunology (ACAAI) 2012 Annual Scientific Meeting.

"Only 4% of physicians internationally are using self- or home therapy for the treatment of acute attacks," lead author Puneet Bajaj, MD, from the Penn State–Hershey College of Medicine in Pennsylvania, told Medscape Medical News.

"The majority of physicians still treat these patients in a hospital setting, and this leads to treatment delays and poor outcomes," Dr. Bajaj said.

HAE is a rare disorder characterized by sudden and recurrent episodes of edema involving different parts of the body, including the face, hands, feet, larynx, and abdomen. Episodes can be painful and, depending on where they occur, life-threatening or even fatal.

"Although it is a rare disease, the patients usually experience severe debilitating attacks, which significantly impact their quality of life. An important part of the treatment strategy is to have the medicines available to patients at home and to train them so that they can use the medicine immediately at the onset of symptoms," Dr. Bajaj said. "This has been shown to lead to early resolution of symptoms and improve quality of life," she explained.

Dr. Bajaj and her team reviewed data from the Hereditary Angioedema Survey of international physicians, which was conducted by the World Allergy Organization in 2010/11 specifically to determine how physicians manage acute HAE attacks.

The 201 physician respondents were mainly from Asia, Europe, and South America. The majority (84%) were allergy and immunology specialists practicing in an academic medical center.

Most (64%) reported treating 1 to 5 HAE patients in the previous year. Only 36% reported treating 2 or more new HAE cases per year.

When asked about the characteristics of their patients, respondents indicated that, in 39% of their patients, the first onset of HAE symptoms occurred at 11 to 17 years of age.

The most problematic symptoms during an acute attack were reported to be throat swelling (in 48% of patients), facial swelling (23%), and abdominal pain (15%).

Of the patients who did not receive at-home or on-demand treatment, 58% had 1 or more acute attacks per month, and most required frequent hospitalization (63% were treated in the emergency department and 21% were treated in a hospital ward).

Only 4% of patients treated themselves at home. Another 1% of patients were treated by home healthcare personnel, Dr. Bajaj reported.

Although a C1-esterase inhibitor was the most commonly prescribed treatment, 33% of the survey respondents reported not prescribing it, she said.

"Most of these physicians, even though they work in academic centers, follow very few patients on an annual basis, and the great majority still treat these patients in a hospital setting," Dr. Bajaj said.

Physicians who practice in the United States are only marginally better when it comes to using at-home treatments, she added.

"In this study, we focused on how this disease is being treated worldwide. However, American physicians were found to be treating acute attacks in home or self-administered settings in 11.5% cases, compared with 5.0% on the international level. So American physicians are marginally better than international physicians," Dr. Bajaj said.

"Patients with HAE must have medications available at home, and they should be self-trained or have home healthcare personnel available to administer the medicine at the earliest onset of symptoms. Delay in treatment can cause more severe symptoms and a longer duration of symptoms," she explained.

Dr. Bajaj hopes that this study will increase awareness about "HAE among treating physicians and make them recognize the role of self and home therapy in symptom control."

HAE is an abnormality of the inflammatory cascade that induces an upregulation of swelling and can be very debilitating, said John Oppenheimer, MD, clinical professor of medicine at the New Jersey Medical School in Newark, who was not involved with the study.

"These people could have repetitive, severe abdominal cramping bringing them to the emergency room, and more frightening, difficulty breathing, but we now have modalities that we can use acutely to treat the attacks. There have been several studies showing a profound rapid resolution of these frightening symptoms," Dr. Oppenheimer told Medscape Medical News.

This study shows that there is a serious underappreciation of the treatment that is available, he said. It "reinforces the need to get the word out to clinicians and to let them know that there are therapies that can be used acutely. Some can even be used chronically," he explained. He described a patient in his own practice who now has a normal life because she has options available to her at the first sign of symptom onset.

"There may be some fear involved because the therapy is injectable, but if we weigh this against the fear of being short of breath...or having swelling in your throat," the choice becomes clear. "Word needs to get out," Dr. Oppenheimer said.

"I think many clinicians are not aware of this on-demand treatment.... We need to understand the illness, know there are treatments available, and get that message out to clinicians. For patients, we need to reinforce the message that we can do something to change outcomes and they do not have to be left in the lurch with no option but to try to get to the emergency room as quickly as possible," he noted.

Dr. Bajaj has disclosed no relevant financial relationships. Dr. Oppenheimer reports financial relationships with GlaxoSmithKline, Merck, AstraZeneca, Boehringer Ingelheim, MedImmune, and Novartis.

American College of Allergy, Asthma & Immunology (ACAAI) 2012 Annual Scientific Meeting: Abstract 33. Presented November 12, 2012.