Results Patient Demographics and Disposition A total of 168 patients were randomized to treatment by 26 investigators in 4 countries. Of these, 86 were treated with eplerenone and 82 received losartan, which provided 88% power to detect a 3.5-mm Hg difference in seated diastolic blood pressure. The characteristics of the patient groups were similar at baseline ( Table I ). Mean seated blood pressures at baseline were similar in the eplerenone and losartan groups ( Table I ). Baseline geometric mean active plasma renin values also were similar in both groups (P = .408). The group mean values of the baseline active plasma renin levels <7.6 pg/mL (<13 mU/L) in both treatment groups confirm that the population met the protocol-specified definition of low-renin hypertension. The disposition of the patients during the conduct of the study is shown in Figure 2. Figure 2. (click image to zoom) Patient disposition. Blood Pressure Effects At the week 8 end point, the mean change from baseline in systolic blood pressure in the eplerenone group was significantly greater than in the losartan group (−15.8 ± 1.70 and −10.1 ± 1.70 mm Hg, respectively; P = .017) (Figure 3). The adjusted mean change from baseline in diastolic blood pressure after 8 weeks was −9.3 ± 0.96 mm Hg in the eplerenone group and −6.7 ± 0.96 mm Hg in the losartan group, P = .05 (Figure 3). Figure 3. (click image to zoom) Adjusted mean change from baseline in diastolic and systolic blood pressure at weeks 8 and 16. *Noninferiority of eplerenone to losartan was established at both time points (P < .001). †P = .017 versus losartan. ‡P = .05 versus losartan. DBP, diastolic blood pressure; SBP, systolic blood pressure. At the week 16 end point, 40 patients in the eplerenone group and 25 patients in the losartan group remained at the initial study medication doses of 100 mg of eplerenone and 50 mg of losartan daily, respectively. A total of 23 patients were at the second dose level at the end of the study, either receiving eplerenone 200 mg (n = 12) or losartan 100 mg (n = 11). A greater proportion of patients in the losartan group than in the eplerenone group required additional therapy with hydrochlorothiazide at week 8 (42.0% vs 22.5%) and at week 16 (55.6% vs 32.5%; P = .003 for eplerenone vs losartan log-rank test) ( Table II ). Comparable antihypertensive effects were seen for the 2 study drugs by week 16, after hydrochlorothiazide was added to achieve blood pressure control. The systolic blood pressure response according to the baseline active renin level was examined according to tertiles of active renin: <5.5 pg/mL (9.4 mU/L), 5.5 to 8.7 pg/mL (9.4-14.8 mU/L), and >8.7 pg/mL (14.8 mU/L). Eplerenone was consistently effective in lowering systolic blood pressure regardless of baseline renin level. Losartan response was associated with renin levels; specifically, patients with higher baseline renin levels had the greatest reduction in systolic blood pressure. In contrast, patients with lower baseline renin levels had greater systolic blood pressure reductions with eplerenone than with losartan (P < .015 in the lowest tertile) (Figure 4). Figure 4. (click image to zoom) Mean change in systolic blood pressure by tertile of baseline active renin at week 8 (monotherapy). Asterisk indicates P = .015 versus losartan. Dagger, P = .067 versus losartan. Renin-aldosterone Responses Active renin levels increased in both groups, with a greater increase in the losartan group, which was not significantly different from the eplerenone-treated group at week 8 (P = .416) and week 16 (P = .635) (Figure 5). As expected, in the eplerenone group, there were significant increases from baseline in serum aldosterone at the week 8 and 16 end points (P < .001). Increases in aldosterone levels were dose dependent, suggesting that increasing the eplerenone dose, along with adding hydrochlorothiazide, contributed to the enhanced blood pressure reductions observed at the week 16 end point. Within the losartan group, there was a significant reduction of aldosterone by week 8; however, by week 16, the reduction was no longer statistically significant. Regression analysis showed no association between baseline plasma active renin, serum aldosterone, or aldosterone/renin ratios and change in diastolic blood pressure within either treatment group. Figure 5. (click image to zoom) Percent change from baseline in active renin and serum aldosterone levels at weeks 8 and 16. Asterisk indicates P ≤ .01 versus losartan. Dagger, after hydrochlorothiazide add-on therapy was permitted. Safety and Tolerability Most patients in each group were exposed to the study drugs for at least 3 months (eplerenone 78%, losartan 82%). Treatment-emergent adverse events were reported by 62.8% (54/86) of patients in the eplerenone group and by 72.0% (59/82) of patients in the losartan group. There were no differences in adverse events among treatments, and most treatment-emergent adverse events were mild or moderate in severity. The adverse events that occurred in more than 5% of both eplerenone and losartan-treated patients were headache, upper respiratory tract infection, and dizziness. No single adverse event was reported significantly more frequently in either treatment group. No deaths occurred in either group. Adverse events considered serious were reported in 3 eplerenone patients (hyperparathyroidism, angina, and abnormal thinking) and 1 losartan patient (noncardiac chest pain); none of these events were attributed to the study medication by site investigators. There were 2 reports of gynecomastia and 1 of impotence in eplerenone-treated men. One event of impotence was reported in a losartan-treated male patient, and 2 events of menstrual disorder were reported in losartan-treated female patients. There was one eplerenone-treated patient (100-mg group) who had a transiently elevated potassium level (5.7 mEq/L at week 14 and 4.1 mEq/L at week 16). Thus, it is unclear whether this was due to the hemolysis or the study drug. Printer- Friendly Email This Am Heart J. 2005;150(3):423-433. ©2005 Mosby, Inc. This is a part of article Eplerenone vs. Losartan in Low-Renin Hypertension Patients Taken from "Price Compare Tadalafil" Information Blog |