Impact of renal dysfunction on clinical outcomes of acute ischemic stroke

Choi, Joon Seok; Kim, Ha Yeon; Oak, Chan Young; Kim, Min Jee; Kim, Chang Sung; Oh, Seul Hyun; Lee, Hyung Chul; Park, Jeong Woo; Bae, Eun Hui; Ma, Seong Kwon; Kim, Nam Ho; Kim, Soo Wan

Abstract

BACKGROUND/AIMS
Chronic kidney disease is recognized as an independent risk factor for coronary artery disease. It is unknown whether renal function predicts clinical outcomes of acute ischemic stroke. The present study was aimed at examining the correlation between the degree of renal dysfunction and stroke outcome.
METHODS
Our retrospective study included 282 consecutive patients hospitalized due to acute ischemic stroke. Renal function was assessed by the estimated Glomerular filtration rate (GFR), using two METHODS: Cockcroft-Gault equation and Modification of Diet in Renal Disease (MDRD) equation. Each of the estimated GFRs were categorized into three groups (Group I: > or = 60 mL/min/1.73 m2, Group II: 45~59 mL/min/1.73 m2, Group III: 15~44 mL/min/1.73 m2). From collected patient databases, we compared mortality and rate of hospitalization to GFR at 1 month and 12 months follow up.
RESULTS
Our study found that, based on the GFR, the 1 year mortality, using the Cockcroft-Gault equation, was 6.0% in group I, 20.3% in group II and 21.1% in group III and, using the MDRD equation, 9.1%, 12.5% and 37.5%, respectively. Patients with lower GFRs exhibited an increased odds ratio for 1 year mortality when estimated by the Cockcroft-Gault equation: 3.97 (1.7~9.2, 95% CI) in group II and 4.16 (1.2~14.5, 95% CI) in group III. Based on the MDRD equation, patients with lower GFRs also exhibited an increased odds ratio for 1-year mortality: 1.43 (0.5~4.4, 95% CI) in group II and 6.00 (1.3~26.8, 95% CI) in group III. The adjusted odds ratio for 1-year mortality also increased based on our analysis using either equation.
CONCLUSIONS
Decline of GFR and severity of chronic kidney disease are associated with poor clinical outcomes of acute ischemic stroke.