Low-dose spironolactone safe, effective in T2D patients with chronic kidney disease

Treatment with low-dose spironolactone results in reduced albuminuria without causing hyperkalaemia in patients with type 2 diabetes (T2D), reports a study.

This multicentre, open-label, randomized controlled trial was conducted from July 2016 to November 2020 in ambulatory care at three diabetes medical institutions in Japan to determine whether a low-dose spironolactone (12.5 mg/d) could lessen the risk of hyperkalaemia while maintaining its effect on decreasing albuminaemia.

In total, 130 adults with T2D and albuminuria (≥30 mg/gCre), estimated glomerular filtration rate ≥30 mL/min/1.73 m², and serum potassium level <5.0 mEq/L were randomized to spironolactone-administered or control groups. The authors then estimated the changes in urine albumin-to-creatinine ratio (UACR) from baseline over the 24-week interventional period.

Patients who received spironolactone achieved a significant decrease in UACR from baseline (mean reduction, 103.47 mg/gCre) compared with those in the control group, who had an increased UACR (mean increase, 63.93 mg/gCre; p=0.0007, Wilcoxon rank-sum test and t test).

Of note, the spironolactone group showed a statistically significant increase in serum potassium levels, but none of the patients had a potassium level ≥5.5 mEq/L at 24 weeks. In addition, those with a higher initial serum potassium level leaned toward a smaller increase (estimate, ‒0.37, analysis of covariance).

“Spironolactone administration, the oldest known and most cost-effective mineralocorticoid receptor antagonist, at lower doses should be reconsidered,” the authors said.