Longitudinal Association between Clinical Biomarkers for Cardiovascular Disease and Disease Progression in Chronic Kidney Disease Patients by Race/Ethnicity

Abstract

Background: It is likely that there are ten times more Americans at risk for chronic kidney disease (CKD) than there are currently diagnosed. Public health efforts to close this gap with screenings have been stalled by the unclear risk factor etiology of CKD. Objective: A hospital-based study was undertaken to examine the association of clinical biomarkers with the risk of incident cardiovascular disease (CVD) and disease progression in patients with early stages of CKD by race/ethnicity. Methods: A total of 289 patient records from the Division of Nephrology were reviewed using a retrospective cohort study design. Patients diagnosed from 2007-2009 with CKD, but without CVD at baseline, were reviewed using a retrospective cohort study design. Kaplan-Meier models were applied to compare time-to-event curves (incident CVD and progression of CKD) by race/ethnicity. Cox proportional hazard regression models were used to assess risk factor significance for the events. A CKD event was defined as an increase in disease severity by CKD stage progression, and a CVD event included angina, atrial fibrillation, congestive heart failure, coronary artery disease, myocardial infarction, or stroke. Subjects were evaluated for both outcomes separately. Results: After excluding records with missing race/ethnicity information, 272 patients remained in the study. Of them, 72% were African American 21% were White, and 7% were Hispanic. Overall, 15.1% of the patient population experienced a CKD event, while 10.3% experienced a CVD event. The cohort incidence of CVD was 28 per 100,000 person-years, but was significantly higher in Hispanic patients (183 per 100,000 person-years, p < 0.0001) as compared to African American (48.6 per 100,000 person-years) and White (49.4 per 100,000 person-years) patients. Relative risks for early CKD progression indicate that minorities have less than half the risk of White patients for increase in disease severity, though a greater proportion of African Americans will have experienced a CKD or CVD event. Conclusions: Minorities with CKD seem to fare worse than White patients when evaluated for CVD event risks, while White patients seem to have greater CKD severity when compared to minorities. A greater proportion of Hispanic patients were observed to enter the study at an earlier stage of CKD as compared to African American and White patients. To improve CKD outcomes in all populations, a double-model of baseline and changes in risk factors would be useful for healthcare providers to predict and control for disease progression in patients with CKD.%%%%M.P.H., Public Health – Drexel University, 2010