Acute kidney injury risk prediction in patients undergoing coronary angiography in a national veterans health administration cohort with external validation

Background-acute kidney injury (aki) occurs frequently after cardiac catheterization and percutaneous coronary intervention. although a clinical risk model exists for percutaneous coronary intervention,no models exist for both procedures,nor do existing models account for risk factors prior to the index admission. we aimed to develop such a model for use in prospective automated surveillance programs in the veterans health administration. methods and results-we collected data on all patients undergoing cardiac catheterization or percutaneous coronary intervention in the veterans health administration from january 01,2009 to september 30,2013,excluding patients with chronic dialysis,endstage renal disease,renal transplant,and missing pre- and postprocedural creatinine measurement. we used 4 aki definitions in model development and included risk factors from up to 1 year prior to the procedure and at presentation. we developed our prediction models for postprocedural aki using the least absolute shrinkage and selection operator (lasso) and internally validated using bootstrapping. we developed models using 115 633 angiogram procedures and externally validated using 27 905 procedures from a new england cohort. models had cross-validated c-statistics of 0.74 (95% ci: 0.74-0.75) for aki,0.83 (95% ci: 0.82-0.84) for akin2,0.74 (95% ci: 0.74-0.75) for contrast-induced nephropathy,and 0.89 (95% ci: 0.87-0.90) for dialysis. conclusions-we developed a robust,externally validated clinical prediction model for aki following cardiac catheterization or percutaneous coronary intervention to automatically identify high-risk patients before and immediately after a procedure in the veterans health administration. work is ongoing to incorporate these models into routine clinical practice. © 2015 the authors.