Prevalence, predictors, and outcomes of cardiorenal syndrome in children with dilated cardiomyopathy: a report from the Pediatric Cardiomyopathy Registry

Background The association of cardiorenal syndrome (CRS) with mortality in children with dilated cardiomyopathy (DCM) is unknown. Methods With a modified Schwartz formula, we estimated glomerular filtration rates (eGFR) for children ≥1 year of age with DCM enrolled in the Pediatric Cardiomyopathy Registry at the time of DCM diagnosis and annually thereafter. CRS was defined as an eGFR of <90 mL/min/1.73 m 2 . Children with and without CRS were compared on survival and serum creatinine concentrations (SCr). The association between eGFR and echocardiographic measures was assessed with linear mixed-effects regression models. Results Of 285 eligible children with DCM diagnosed at ≥1 year of age, 93 were evaluable. CRS was identified in 57 of these 93 children (61.3 %). Mean (standard deviation) eGFR was 62.0 (22.6) mL/min/1.73 m 2 for children with CRS and 108.0 (14.0) for those without ( P < 0.001); median SCr concentrations were 0.9 and 0.5 mg/dL, respectively ( P < 0.001). The mortality hazard ratio of children with CRS versus those with no CRS was 2.4 (95 % confidence interval 0.8–7.4). eGFR was positively correlated with measures of left ventricular function and negatively correlated with age. Conclusions CRS in children newly diagnosed with DCM may be associated with higher 5-year mortality. Children with DCM, especially those with impaired left ventricular function, should be monitored for renal disease.