Health Care Costs by Type of Expenditure across eGFR Stages among Patients with and without Diabetes, Cardiovascular Disease, and Heart Failure.

BACKGROUND CKD is associated with higher health care costs that increase with disease progression. However, research is lacking on the type of health care costs associated with CKD across all stages in a general population with a substantial comorbidity burden. METHODS Using electronic medical records of an integrated delivery system, we evaluated health care costs by expenditure type in general and in patients with CKD by eGFR and presence of comorbidities. We categorized 146,132 patients with eGFR data in 2016 or 2017 and examined nonmutually exclusive groups according to presence of diabetes mellitus, cardiovascular disease, or heart failure. We used 1 year of follow-up data to calculate outpatient, inpatient, emergency, pharmaceutical, dialysis, and total health care costs by eGFR (Kidney Disease Improving Global Outcomes-defined eGFR categories), adjusted for age, sex, and nonwhite race. RESULTS Mean total health care costs among patients with CKD without comorbidities were 31% higher than among patients without CKD ($7374 versus $5631, respectively). Hospitalizations accounted for 35% of total costs among those with CKD and no comorbidities but up to 55% among patients with CKD and heart failure. The proportion of costs attributable to hospitalizations accelerated with declining kidney function, reaching as high as 66%. CONCLUSIONS Poorer kidney function and the presence of diabetes mellitus, cardiovascular disease, or heart failure drive substantial health care costs and increase the proportion of costs attributable to inpatient care. The large contribution of inpatient costs begins in earlier stages of CKD and escalates as kidney function declines. Additional therapies to reduce CKD incidence, slow CKD progression, and lower hospitalization risk are needed to benefit patients and reduce CKD's economic burden.