Abstract P328: Evaluation of Hyperkalemia and the Use of Aldosterone Antagonists in Resistant and Secondary Hypertension in a Hypertension Referral Center
Purpose/Background: Since publication of the RALES trial, reports of hyperkalemia associated with aldosterone antagonists have increased. These reports have likely negatively influenced prescribing in many patient populations that could receive benefit from aldosterone antagonists. The American Heart Association recently issued a scientific statement that highlights the potential value of aldosterone antagonists in both resistant and secondary hypertension. The purpose of this study was to review the use of aldosterone antagonists and incident hyperkalemia among patients routinely followed in the University of Mississippi Medical Center (UMMC) Hypertension Clinic.
Methodology: A retrospective analysis was designed to review all patients followed by the clinic and prescribed an aldosterone antagonist and with a potassium level above 5.0 mEq/L over the past 5 years. Data collected included patient laboratory results, initial and final blood pressure, concomitant medications, chronic disease status, demographics and any related risk factors.
Results: An initial review identified 5,967 patients and 101,200 potassium laboratory results over the 5-year period; 108 patients had potassium levels above 5.0 mEq/L and 830 were prescribed an aldosterone antagonist. Of these, 44 patients met the inclusion criteria of receiving an aldosterone antagonist and having elevated potassium. Most of these patients had an indication of resistant hypertension.
The majority were African American (61%, 27of 44) and female (84%, 37 of 44), with a mean age of 65 years (range, 39-88) and baseline potassium of 4.4 (3.4-5.2) mEq/L. The mean potassium for the initial episode of hyperkalemia was 5.4 mEq/L (5.0-6.8) and occurred on average 15 months (1-81) after initiation of the aldosterone antagonist. The mean for the peak potassium concentration was 5.5 mEq/L (5.1-6.8), occurring 19 months (1-81) after initiating an aldosterone antagonist. On medication review, most patients were on another medication that could influence potassium levels (38 on ACEi or ARB, 4 potassium supplement, 2 NSAIDs, 2 other). The overall discontinuation rate for hyperkalemia associated with the use of an aldosterone antagonist 1% (9 of 830).
Conclusion: Aldosterone antagonists are an effective option for the management of hypertension, especially resistant and secondary causes of hypertension with appropriate patient selection. In our clinic, blood pressure control was achieved in 63% (179 of 286) of patients receiving an aldosterone antagonist at the final clinic visit reviewed, compared to 12% (716 of 5,967) at clinic entry and relatively few experienced hyperkalemia. Our results support the consideration and use of aldosterone antagonists for many patients with hypertension.
- © 2013 by American Heart Association, Inc.