Chronic kidney disease is common and expensive and interacts with diabetes and cardiovascular disease in the dually-enrolled population

Chronic kidney disease (CKD) is an important public health challenge due to increased risk of cardiovascular events and progression to end stage renal disease (ESRD). Because state Medicaid agencies cover some of their health care costs, they may have a particular interest in Medicare/Medicaid dually-enrolled patients. In this population we analyzed the interacting prevalence and costs for persons diagnosed with CKD, diabetes mellitus (DM), congestive heart failure (CHF), and ESRD. Diagnosis of CKD, DM, and CHF was defined by Medicare claims (Two Part B or one Part A claim with codes for the disease). Costs are total 2004 Medicare costs. Nationally, the 5.9% of patients diagnosed with CKD accounted for 16.6% of costs: a multiplier of 2.8. For DM the multiplier was 1.5 (28.4% of population; 42.4% of costs); for CHF the multiplier was 2.5 (13.8%; 34.2%). For ESRD the multiplier was 5.5 (1.9%; 10.2%). Among those diagnosed with CKD, 56% were also diagnosed with diabetes and 44% were also diagnosed with CHF. The 1.7% of the population with diagnoses of CKD, DM, and CHF accounted for 6.9% of costs: a multiplier of 4.1. State-level analyses were also performed. Size and costs of diagnosed populations varied widely while cost multipliers varied little. Sensitivity of claims-based CKD diagnosis is low, but specificity is high. So true prevalence is even higher than reflected in these analyses. CKD's high cost multiplier, broad overlap with DM and CHF, and relatively high prevalence has implications for disease management and prevention efforts.