Abstract 20657: The Incidence and Risk of Hypokalemia in Patients With High Risk Hypertension: The ACCOMPLISH Study
A recent data have suggested an increased cardiovascular risk (CVR) with a serum potassium (K+) <4.0 meq/l in patients (pts) with chronic renal disease and or heart failure (HF). The CVR of serum K+ <4.0 meq/L in pts with high risk hypertension (HTN) has not however been defined. We therefore retrospectively analyzed pts with high risk stage 2 HTN randomized to the combination of either benazepril/HCTZ (B/H) or benazepril/amlodipine (B/A) in the ACCOMPLISH trial in which pts randomized to B/A had a significant reduction in CVR vs. B/H despite a similar reduction in blood pressure (BP) (Jamerson, NEJM, 2008). At baseline (BL) 9156 pts had a serum K+ ≥4.0 and 2283 pts <4.0 meq/l. While pts with serum K+ <4.0 meq/l at BL did not have an increased risk of developing the primary endpoint consisting of CV death, myocardial infarction (MI), stroke, hospitalization for unstable angina (UA), coronary revascularization, resuscitated sudden cardiac death (SD) they did have a significant 23% risk increase for the secondary endpoint of CV death, MI or stroke compared to those with a serum K+ ≥4.0 meq/l (p=0.028). Of the 9012 pts with a K+ ≥4.0 meq/l at BL, 15.8% (n=716) randomized to B/H and 9.3% (n=418) to B/A had a fall in serum K+ to <4.0 meq/l (p<0.0001). While the primary endpoint rates were similar in those pts who had a decrease in serum K+ from BL ≥4.0 to <4.0 meq/l (n=1134) compared to those who did not (n=7878) there was a greater incidence of hospitalization for HF (HR 2.35, p<0.0001) and a trend toward a greater incidence of coronary events including MI, UA, and SD (HR 1.29, p=0.08) in those who had a fall in serum K+ to <4.0 meq/l from BL. In conclusion, hypokalemia at BL defined as a serum K+ <4.0 meq/l, is associated with an increased CVR in pts with high risk stage 2 HTN. A decrease in serum K + from BL to <4.0 meq/l is associated with an increase in hospitalization for HF and a trend toward an increase in coronary events. Thus, while ACE-Is may partially protect from thiazide-induced hypokalemia they do not prevent it. Although there was no difference in the CVR of pts randomized to B/H vs B/A who had a fall in serum K+ to <4.0 meq/l from BL the lower incidence of developing serum K+ <4.0 meq/l in pts on B/A suggests a further advantage of this combination compared to B/H despite a similar reduction in BP.
- © 2010 by American Heart Association, Inc.