Development and Validation of Staging Systems for AA… : Journal of the American Society of Nephrology
absence of validated staging systems. Methods: Newly diagnosed patients with AA amyloidosis from the Pavia (n=233, testing cohort) and Heidelberg (n=243, validation cohort) centers were included in the study. Cut-offs of continuous variables were determined by ROC analysis predicting death or dialysis at 24 months. Prognostic factors included in staging systems were identified by multivariable models in the testing cohort. Results: Age ≥65 years, estimated glomerular filtration rate (eGFR) 130 ng/L and/or N-terminal BNP [NT-proBNP] >1000 ng/L) were predictors of overall survival and included in the staging system (all with simplified coefficients 1). Mean 36-months overall survival was lower with higher staging system scores (score 0-1: 92%; score 2: 72%; score 3: 32%). These results were confirmed in the validation cohort. For kidney failure, variables selected to enter in the staging system model w