Intensive Blood Pressure Reduction May Not be Safe for Patients With Renal Impairment

July 8, 2021
Excessive blood pressure (BP) reduction for acute intracerebral haemorrhage can have dire consequences when kidney function is low, according to a study published in Neurology. Previous clinical studies have shown that intense BP reduction in patients with acute intracerebral haemorrhage can improve clinical outcomes. However, excessive BP reduction can damage the kidneys, especially in people who already have chronic kidney disease. “Without a clear understanding of how kidney function affects the overall outcome when controlling BP in these situations, doctors cannot make the best decisions for immediate stroke treatment,” explained Masatoshi Koga, MD, National Cerebral and Cardiovascular Center, Suita, Japan. For the study, Mayumi Fukuda-Doi, MD, National Cerebral Cardiovascular Center, and colleagues conducted post hoc analyses of the Antihypertensive Treatment of Acute Cerebral Hemorrhage II (ATACH-2) study. In ATACH-2, researchers randomised patients to the intensive antihypertensive group (systolic BP 110-139 mm Hg) or the standard antihypertensive group (140-179 mm Hg) within 4.5 hours of onset of intracerebral haemorrhage. The primary endpoint was the rate of death or severe functional disability at 3 months. In the current study, researchers divided 974 patients into 3 categories based on their estimated glomerular filtration rate (eGFR) at the time of admission, which correspond to normal function, mild loss of function, and decreased kidney function. The median baseline eGFR was 88 ml/min/1.73 m2. Of the cohort, 46.3%, 37.3%, and 16.4% of patients had baseline eGFR values of ≥90, 60 to 89, and 2, respectively. The researchers found that compared with normal eGFR (≥90 ml/min/1.73 m2), higher odds of death or disability were noted among those with eGFR values of 2 (adjusted odds ratio (OR) = 2.02; 95% confidence interval [CI], 1.25-3.26), but not among those with eGFR values of 60 to 89 ml/min/1.73 m2 (OR = 1.01; 95% CI, 0.70-1.46). The odds of death or disability were significantly higher in the intensive arm among patients with decreased eGFR; the ORs were 0.89 (95% CI, 0.55-1.44), 1.13 (0.68-1.89), and 3.60 (1.47-8.80) in patients with eGFR values of ≥90, 60 to 89, and 2, respectively. “Although intense lowering of BP can reduce the risk of hematoma expansion and prevent brain damage after stroke, we found that it can harm those with eGFR values SOURCE: National Cerebral and Cardiovascular Center