Patients with hereditary angioedema (HAE) experience prodromal or early warning symptoms before nearly three-quarters of their HAE attacks, according to survey findings presented today at the 2010 American Academy of Allergy, Asthma & Immunology (AAAAI) Annual Meeting. According to researchers, this high frequency suggests that prodromal symptoms may reliably indicate when to initiate treatment to help prevent an acute HAE attack.
To identify the prodromal symptoms patients experienced before an HAE attack, two separate surveys were conducted. A prospective survey, administered to patients enrolled in an open-label study of human pasteurized C1 esterase inhibitor concentrate, surveyed patients about their prodromal symptoms at the time they were seeking treatment for an HAE attack. A retrospective survey focused on questions related to prodromal symptoms prior to the patient's last HAE attack.
According to survey findings, patients experienced prodromal symptoms before 70.5 percent of the 305 reported HAE attacks. The most commonly reported prodromal symptoms were fatigue (45%), gastrointestinal complaints (41%), muscle aches or flu-like symptoms (26%), rash (21%) and numbness or tingling (10%).
"To date there has been limited published data regarding the importance of identifying prodromal symptoms of an HAE attack," said Timothy J. Craig, D.O., Professor of Medicine and Pediatrics at Penn State University in Hershey, PA., and one of the study's investigators. "Our findings suggest that the onset of these warning signs may be the time to initiate on-demand treatment in order to prevent an acute attack of HAE."
HAE is a genetic disorder affecting approximately 6,000 to 10,000 Americans and is caused by a deficiency of C1-INH, which is inherited in an autosomal dominant manner. Patients who have abdominal attacks can experience episodes of severe pain, diarrhea, nausea, and vomiting caused by swelling of the intestinal wall. Attacks that involve the face and larynx can result in airway closure, asphyxiation, and, if untreated, death. Diagnosis of HAE requires a blood test to confirm low or abnormal levels of C1-INH.