Comparative validation of the Mayo Clinic imaging classification and PROPKD score for predicting ADPKD progression across diverse ethnic cohorts.

Abstract

Background: Autosomal dominant polycystic kidney disease (ADPKD) is a common cause of end-stage kidney disease (ESKD). In this retrospective multicenter cohort study, we aimed to evaluate the concordance, sensitivity and specificity of the predictive abilities of the Mayo Clinic Imaging Class (MCIC) and Predicting Renal Outcome in Polycystic Kidney Disease (PROPKD) score for progression to ESKD.

Methods: Data for adult ADPKD patients of diverse ethnicities were obtained from 4 renal centers (Saint Louis, Kayseri, Bursa, Istanbul). The predictive value of MCIC and PROPKD was compared for progression to ESKD. ESKD was defined by the following criteria: (1) two consecutive estimated glomerular filtration rate (eGFR) < 15 ml/min/1.73m² more than 1 month apart and/or (2) initiation of kidney replacement therapy.

Results: One hundred eighty-seven ADPKD patients with PKD1 or PKD2 variants were included, with the majority identifying as White (93%), followed by Black (6%) and Hispanic (0.5%). The PROPKD score showed moderate ability (AUC = 0.702) to predict progression to ESKD, performing better in Black patients (AUC = 0.800) than in White patients (AUC = 0.764). However, the predictive accuracy declined (AUC = 0.644) when the PROPKD score was categorized into risk levels (low, intermediate, high). The MCIC showed lower ability (AUC = 0.578) to predict progression to ESKD than the PROPKD score. Using LASSO regularization and multivariable Cox regression, self-identified Black ethnicity [HR = 12.24 (95% CI: 3.19-46.94, p < 0.001)] and age at initial follow-up [HR = 1.05 (95% CI:1.01-1.09, p = 0.007)] emerged as significant predictors of progression to ESKD.

Conclusions: The PROPKD score appears to be a useful tool for predicting ADPKD progression across various ethnic groups, with self-identified Black ethnicity and age at initial follow-up emerging as key predictors of kidney failure.