Evaluation of health-related quality of life in patients with Cushing's syndrome with a new questionnaire

Chronic exposure to hypercortisolism has significant impact on patient's health and health-related quality of life (HRQoL), as demonstrated with generic questionnaires. We have developed a disease-generated questionnaire to evaluate HRQoL in patients with Cushing's syndrome (CS: CushingQoL). Objective: Validate the CushingQoL questionnaire in patients with CS in clinical practice conditions. Design: Observational, international, cross-sectional study. Methods: A total of 125 patients were recruited by 14 investigators from Spain, France, Germany, The Netherlands, and Italy over a 2-month period. Clinical and hormonal data were collected and correlated with results of the generic short form 36 (SF-36) questionnaire, a question on self-perceived general health status and the CushingQoL score. Results: A total of 107 patients were pituitary-dependent and 1.8 adrenal-dependent CS: 104 (83%) were females, mean age 45 years (range 20-73 years): 39 (31%) were currently hypercortisolemic; and 47 (38%) adrenal insufficient. In clinical practice, CushingQoL was feasible (117: 94% of patients fully responded to the questionnaire in a mean time of 4 min), reliable (Crohnbach's alpha = 0.87), and valid (factorial analysis demonstrated unidimensionality and Rasch analysis lead to it final version with 12 items). A significant (P<0.001.) correlation was observed between CushingQoL score and patients self-perceived general health status and dimensions of SF-36 (Pearson's correlation coefficient >= 0.597). Patients with current hypercortisolism scored worse (lower) than those without (44 +/- 22 vs 56 +/- 21, P=0.004). Linear regression analysis identified female gender and hypercortisolism as significant predictors for worse QoL. Conclusion: CushingQoL is useful to evaluate HRQoL in patients with CS and correlates with clinical parameters.