Estimated glomerular filtration rate and risk of poor outcomes after stroke

BACKGROUND: Relationship of estimated glomerular filtration rate (eGFR) with complications after stroke has not been fully characterized for entire clinical spectrum of eGFR and for the fluctuation in eGFR during hospital stay.

METHODS: Data from the Norfolk and Norwich Stroke Registry recorded between January 2003 and April 2015 was analysed. eGFR was categorized into six clinically relevant categories as per Kidney Disease Improving Global Outcomes guidelines. Change in eGFR during acute admission was categorized into: within 5% change (ref.), 5-20% decline, >20% decline, 5-20% increase and >20% increase. All-cause mortality, recurrent stroke, incident myocardial infarction, prolonged hospital stay and stroke disability at discharge were outcomes of interest.

RESULTS: 10,329 stroke patients (mean age 77.8 years) were followed for a mean of 2.9 years (30,126 person years). Multivariable adjusted hazard ratios (HRs) (95%CI) for all-cause mortality were 0.91 (0.80-1.04), 0.96 (0.83-1.11), 1.23 (1.06-1.43), 1.54 (1.31-1.82) and 2.38 (1.91-2.97) for eGFR levels 60-89, 45-59, 30-44, 15-29 and <15 respectively, compared to eGFR ≥90 mL/min/1.73m2 . The HR (95%CI) for eGFR change were 1.56 (1.36-1.79), 1.17 (1.05-1.30), 1.47 (1.32-1.62) and 1.71 (1.55-1.88) for >20% decline, 5-20% decline, 5-20% increase and >20% increase, respectively, compared to change within 5%. Results were similar for other outcomes except recurrent stroke.

CONCLUSIONS: Stroke patients with eGFR <45 mL/min/1.73m2 at hospital admission and > 5% decline or increase in eGFR during hospital stay were at substantially high risk of poor outcomes, particularly all-cause mortality, myocardial infarction, prolonged hospital stay and disability at discharge. This article is protected by copyright. All rights reserved.