Comparison of Associations of Reduced Estimated Glomerular Filtration Rate With Stroke Outcomes Between Hypertension and No Hypertension

Background and Purpose— We compared the association of low estimated glomerular filtration rate (eGFR) with stroke outcomes among patients with hypertension and without hypertension. Methods— We used the China stroke registry to identify patients on discharge with the diagnosis of stroke in 2012 and 2013. Low eGFR was defined as <60 mL/min/1.73 m2 . Multivariable analysis was used to evaluate the association of low eGFR with 1-year all-cause mortality, recurrent stroke, poor functional outcome defined as 3 to 6 in modified Rankin Scale (mRS), and ordinal mRS, where the interaction of eGFR category and hypertension status was investigated.Results— Of 5082 patients without hypertension, 221 patients (4.4%) had low eGFR, as compared with 1378 patients (8.6%) previously diagnosed with hypertension. In patients without hypertension, the adjusted odds ratios with 95% confidence interval of low eGFR was 1.88 (1.23–2.88) for all-cause mortality, 1.36 (0.66–2.83) for recurrent stroke, 2.14 (1.45–3.16) for poor functional outcome, and 2.07 (1.58–2.70) for ordinal mRS. In patients with hypertension, low eGFR was associated with all stroke outcomes: 1.80 (1.50–2.16) for all-cause mortality, 1.52 (1.20–1.91) for recurrent stroke, 1.30 (1.11–1.52) for poor functional outcome, and 1.31 (1.18–1.46) for ordinal mRS. The significant interaction between eGFR categories and hypertension was only found for poor functional outcome (P =0.046) and ordinal mRS (P =0.002).Conclusions— Effect of low eGFR on all-cause mortality and recurrent stroke in patients without hypertension was not significantly different from that in patients with hypertension, but low-eGFR patients without hypertension had a higher risk of stroke-related disability than those with hypertension.