Kidney Function Predicts Hospital Discharge, Mortality After Stroke
Patients with an eGFR below 60 mL/min/1.73 m2 were more likely to die in the hospital or be discharged to hospice.
Among patients hospitalized for stroke, those with impaired kidney function are less likely to be discharged home and more likely to die, a new study finds.
Nada El Husseini, MD, MHSc, of Wake Forest Baptist School of Medicine in Winston Salem, North Carolina, and her team analyzed short-term outcomes for 232,236 ischemic stroke patients older than 65 years by their kidney function at admission. The investigators used the Modification of Diet in Renal Disease study equation, which incorporates creatinine level, age, race, and sex, to calculate patients' estimated glomerular filtration rate (eGFR). The investigators considered an eGFR at or above 60 mL/min/1.73 m2 normal kidney function, with eGFR groupings below that level indicating acute kidney dysfunction or chronic kidney disease (CKD).
According to results published online ahead of print in Stroke, 11.8% of patients died during hospitalization or were discharged to hospice, and 38.6% were discharged home. Any level of renal dysfunction at hospital admission was associated with increased risks of inpatient mortality or hospice. After adjustment for relevant demographic and clinical factors, non-dialysis patients with an eGFR below 15 mL/min/1.73 m2 had a significant 2.5 times higher odds for early death or hospice compared with patients who had an eGFR of 60 mL/min/1.73 m2 or greater. This was the highest risk experienced by any of the eGFR groups. The researchers adjusted for comorbidities and stroke severity, so underlying vascular risk factors and poor health may account for the result.
Patients with the worst kidney function at admission also were less likely to be discharged home. Patients with an eGFR of 15 to 29 mL/min/1.73 m2, below 15 mL/min/1.73 m2, and on dialysis had a significant 18%, 28%, and 14% lower odds of discharge, respectively. The relationship of patient and hospital characteristics with mortality and discharge varied with eGFR level.
"Kidney function is clearly an important factor in stroke patients," lead investigator Dr El Husseini told Renal & Urology News. “Understanding the association of admission eGFR and short-term outcomes potentially identifies a high-risk group who may benefit from targeted interventions.”
In line with results from some previous studies, subgroups of women with CKD had slightly lower mortality after stroke than men. Women with an eGFR above 15 mL/min/1.73 m2 were less likely than comparable men to be discharged home.
Study patients, all of whom were Medicare-eligible, were admitted during 2009 to 2012 to 1581 hospitals affiliated with Get With the Guidelines Stroke, a program designed by the American Heart Association and the American Stroke Association to improve guideline-based care for patients hospitalized with stroke or transient ischemia attack. Roughly half of patients (47.3%) had an eGFR at or above 60 mL/min/1.73 m2, 26.6% had an eGFR of 45 to 59, 16.8% had an eGFR 30 to 44, 5.6% had an eGFR 15 to 29, and 0.7% had an eGFR below 15; an additional 2.8% were receiving dialysis. Various pharmaceutical companies have provided funding for Get With the Guidelines Stroke.
1. El Husseini N, Fonarow GC, Smith EE, et al. Renal Dysfunction Is Associated With Poststroke Discharge Disposition and In-Hospital Mortality: Findings From Get With The Guidelines–Stroke. Stroke. 2017;48:327-334. DOI: 10.1161/STROKEAHA.116.014601 [Epub ahead of print]
2. Kidney function in stroke patients associated with short-term outcomes. Wake Forest Baptist Medical Center. Jan 30, 2017. [press release]