Does Renal Dysfunction Predict Mortality After Acute Stroke?: A 7-Year Follow-Up Study

R. S. MacWalter, S. Y.S. Wong, K. Y.K. Wong, G. Stewart, C. G. Fraser, H. W. Fraser, Y. Ersoy, S. A. Ogston, R. Chen
2002 Stroke  
and Purpose-The purpose of this study was to investigate renal function as a long-term predictor of mortality in patients hospitalized for acute stroke. Methods-This was a cohort study done in a Scottish tertiary teaching hospital. Participants included 2042 (993 male) unselected consecutive stroke patients (mean age, 73 years) admitted to hospital within 48 hours of stroke between1988 and 1994. Follow-up was up to 7 years. Main outcome measure was all-cause mortality. Results-The total number
more » ... s-The total number of deaths at the end of follow-up was 1026. Most subjects (1512) had creatinine Ͻ124 mol/L. The mean calculated creatinine clearance was 54.8 mL/min (SD, 23 mL/min). Renal function indexes were analyzed by quartiles with Cox proportional-hazards model. Stroke survivors had higher calculated creatinine clearance and lower serum creatinine, urea, and ratios of urea to creatinine. Calculated creatinine clearance Ն51.27 mL/min significantly predicted better long-term survival in these stroke patients even after adjustment for confounders (age, neurological score, ischemic heart disease, hypertension, smoking, and diuretic use). Similarly, creatinine Ն119 mol/L [relative risk (RR), 1.59; 95% confidence interval (CI), 1.32 to 1.92], urea 6.8 to 8.9 mmol/L (RR, 1.34; 95% CI, 1.09 to 1.65) or Ն9 mmol/L (RR, 1.74; 95% CI, 1.42 to 2.13), and ratio of urea to creatinine Ն0.08573 mmol/mol (RR, 1.24; 95% CI, 1.03 to 1.50) remained significant predictors of mortality after adjustment for confounders. Conclusions-After acute stroke, patients with reduced admission calculated creatinine clearance, raised serum creatinine and urea concentrations (even within conventional reference intervals), and raised ratio of urea to creatinine had a higher mortality risk. This finding may be used to stratify risk and target interventions, eg, the use of angiotensin-converting enzyme inhibitors. (Stroke. 2002;33:1630-1635.)
doi:10.1161/01.str.0000016344.49819.f7 pmid:12053003 fatcat:kv46wcwizjdrxktdvmuelcxvvy