A disease-specific Quality of Life questionnaire for primary aldosteronism

OBJECTIVE: To develop a primary aldosteronism (PA) disease-specific Health-Related Quality of Life (HRQoL) questionnaire. METHODS: We included newly diagnosed patients with PA (n=26), and patients with PA after adrenalectomy (n=25) or treated with mineralocorticoid receptor antagonists (n=25). According to the guidelines for developing HRQoL questionnaires from the European Organization for Research and Treatment of Cancer (EORTC): Phase I: systematic literature review followed by focus group meetings with patients (n=13) resulting in a list of 94 HRQoL issues. Relevance of issues was rated by 18 other patients and by health care professionals (n=15), resulting in 30 remaining issues. Phase II: selected issues were converted into questions. Phase III: the provisional questionnaire was pre-tested by a third group of patients (n=45) who also completed the EORTC core quality of life questionnaire (QLQ-C30). Psychometric testing resulted in a final selection of questions with their scale structure. RESULTS: After the collection and selection of HRQoL issues a provisional questionnaire consisting of 30 items was formed. Of these items, 26 could be assigned to one of the four scales 'physical and mental fatigue', 'anxiety and stress', 'fluid balance' and 'other complaints' cumulatively accounting for 68% of variation in all items. All scales had good reliability and validity. There was a significant correlation of all four scales with the QLQ-C30 in most cases. CONCLUSIONS: We developed the first PA-specific HRQoL questionnaire (PA-QoL) using standard, methodologically proven guidelines. After completion of the final validation (phase IV, international field testing), the questionnaire can be implemented into clinical practice.