A recent study, called TOPCAT, evaluated the effects of spironolactone as a treatment for individuals living with Chronic Kidney Disease (CKD) who are also diagnosed with heart failure with preserved ejection fraction, or HFpEF. This trial included 3,445 patients with CKD who additionally had symptomatic HFpEF. It was an international trial in which patients were randomized to receive spironolactone or placebo. Participants were then observed for 3.3 years to determine the effect of the treatment.
An analysis of data gathered from the 1,767 American participants in the trial indicated that spironolactone effectively achieved the primary endpoint of the study. Patients who received the treatment had much better cardiovascular outcomes including a reduction in risk of experiencing aborted cardiac arrest, hospitalization due to heart failure, or cardiovascular death.
Ultimately, this study indicated a decrease in risk for cardiac complications by 12% in patients who received spironolactone. This percentage was 34% for patients who had an eGFR of 60 or higher. An eGFR measures how well your kidneys are working. An eGFR of 60 or above is considered normal.
Unfortunately however, this trial did was not all good news.
This study showed that while spironolactone improved cardiac outcomes, it also increased patient’s risk of developing Hyperkalemia. Additionally, it decreased renal function in patients. These complications were correlated, with hyperkalemia increasing as renal function decreased. The incidence of these effects for those who had an eGFR of 60 or higher was 6.8 for those taking sprionolactone and 1.4 for those who received placebo (per 100 years). For participants who had an eGFR of 45-60, these numbers were 11.9 for spironolactone and 3.6 for placebo. For eGFR’s which were below 45, they were 14.7 for spironolactone and 5.3 for those taking placebo.
Ultimately, this study shows that while spironolactone may be beneficial for some patients with chronic kidney disease, patients must be carefully monitored while on the treatment. Careful surveillance of these individuals should help to limit their risk of experiencing adverse events such as hyperkalemia or renal dysfunction.
You can read more about this study and which patients spironolactone may be right for here.