Impact of acute hepatic porphyria attack frequency on patient-reported outcomes: results from the Porphyria Worldwide Patient Experience Research (POWER) study

Abstract

Introduction: Acute hepatic porphyria (AHP), a group of rare genetic diseases, is characterized by neurovisceral attacks. Objective: This study evaluated its impact in patients with sporadic or recurrent attacks. Methods: Adult patients having >1 attack within the past two years or receiving prophylactic treatment were recruited from the United States, Italy, Spain, Australia, Mexico, and Brazil for an online survey. Patients taking givosiran were excluded. Differences between patients with sporadic attacks (annualized attack rate [AAR], <6 within past two years) and recurrent attacks (AAR, ≥6) were evaluated. Attacks included those leading to hospitalization, emergency room, outpatient doctor, or self-management. Outcomes were assessed with Generalized Anxiety Disorder-7 (GAD-7), Patient Health Questionnaire (PHQ-8) and burden of chronic symptoms. Results: Of the 92 patients who completed the survey, 60% reported sporadic attacks and 40% recurrent attacks. Most patients were female (sporadic 92.7%; recurrent 86.5%), and the most frequent diagnosis was acute intermittent porphyria (sporadic 83.6%; recurrent 59.4%). Most patients in the sporadic (52.7%) and recurrent (67.6%) groups reported a PHQ-8 score indicating moderate to severe depression; 43.6% in the sporadic and 56.8% of recurrent groups reported a GAD-7 score indicating moderate to severe anxiety. Pain was one of the most burdensome chronic symptoms in the sporadic (50.9%) and recurrent (59.5%) groups. Most patients reported muscle weakness as a top three symptom that limited their daily activities (sporadic 83.3%; recurrent 90.6%). Conclusion: While disease burden appeared greater for AHP patients experiencing recurrent attacks, both sporadic and recurrent group patients experienced a substantial impact on physical, mental, and emotional quality of life.