Angiotensin converting enzyme (ACE) inhibitors and renal function. A review of the current status

Evaluation of the use of evidence-based angiotensin-converting enzyme inhibitor criteria for the treatment of congestive heart failure: opportunities for pharmacists to improve patient outcomes

BACKGROUND

The under-utilization and under-dosing of angiotensin-converting enzyme inhibitors (ACEIs) in patients with congestive heart failure (CHF) continues to be a problem observed in clinical practice.

OBJECTIVE

To develop and implement drug use evaluation (DUE) criteria for the use of ACEIs in patients with CHF which could be used by pharmacists to ensure that all eligible patients receive an ACEI at an appropriate dose.

METHODS

A retrospective chart review of all patients discharged from the study institution with a diagnosis of CHF during the period of March 1 to July 31, 1998 was conducted using the DUE criteria developed.

RESULTS

Of the 138 patients evaluated, only 68.6% were discharged on ACEI therapy. Additionally, only 40% of those discharged on an ACEI achieved target dose. Multiple regression analysis revealed that males were 2.43 times more likely to be discharged on an ACEI than females, while those on concomitant diuretics or digoxin were less likely to be discharged on an ACEI (25% and 18%, respectively).

CONCLUSIONS

The application of these DUE criteria by pharmacists in hospital and community practice has the potential to improve utilization and dosing of this important class of medications for the management of the symptoms and progression of CHF.

Effects of cilazapril on renal haemodynamics and function in hypertensive patients: a randomised controlled study versus hydrochlorothiazide

In this study the efficacy and safety of short-term cilazapril administration on renal haemodynamics were evaluated in mild to moderate hypertensive subjects. Our final goal was to evaluate whether the reduction in blood pressure achieved by treatment was associated with maintained renal function. After a run-in period with placebo, 40 hypertensive subjects without renal or cardiac diseases were randomly allocated to a double-blind 4 week controlled trial with cilazapril 5 mg once a day (20 patients) or hydrochlorothiazide 25 mg once a day (20 patients). Renal haemodynamics measurements included effective renal plasma flow (ERPF) and glomerular filtration rate (GFR) by radionuclide study using 131I-hippuran and 99mTc, according to the methods described by Schlegel and Gates, respectively. Effective renal blood flow [ERBF = ERPF/(1-Ht)], filtration fraction (FF = GFR/ERPF) and renal vascular resistance (RVR = MBP x 80/ERBF) were calculated. At the end of cilazapril and hydrochlorothiazide administration significant decreases (p < 0.001) in SBP, DBP and MBP vs baseline values were observed. In the cilazapril group a significant decrease (p < 0.001) in RVR and FF and a significant increase (p < 0.001) in ERPF and ERBF were also found. In the hydrochlorothiazide group a significant decrease (p < 0.001) in RVR was found. No important side effects were observed with either treatment. In conclusion our data indicate that both cilazapril and hydrochlorothiazide reduced blood pressure equally well but only cilazapril improved renal blood flow and reduced filtration fraction.

New therapeutic agents in the management of hypertension: angiotensin II-receptor antagonists and renin inhibitors

OBJECTIVE

To review the chemistry, pharmacokinetics, and clinical trials of two new classes of antihypertensive drugs, angiotensin II-receptor antagonists and renin inhibitors.

DATA SOURCES

Primary literature on angiotensin II-receptor antagonists and renin inhibitors was identified through a comprehensive medical literature search from 1961 through 1993. This search included journal articles, abstracts, and reports of both animal and human research published in the English language. Indexing terms included renin-angiotensin aldosterone system, renin inhibitors, angiotensin II antagonists, DuP 753, losartan, MK954, A-64662, and Ro 42-5892.

STUDY SELECTIONS

Emphasis was placed on clinical and pharmacokinetic studies in humans for drugs that are currently in Phase I-III research protocols in the US.

DATA EXTRACTION

All available data from human studies were reviewed.

DATA SYNTHESIS

Angiotensin II-receptor antagonists and renin inhibitors may be effective antihypertensives with few adverse effects noted in the small studies completed. Their potential advantage over angiotensin-converting enzyme (ACE) inhibitors includes a possible smaller adverse effect profile. In the past, the clinical utility of angiotensin II-receptor antagonists and renin inhibitors has been limited because of poor oral bioavailability, although newer agents are more readily bioavailable.

CONCLUSIONS

Angiotensin II-receptor antagonists and renin inhibitors may be the next new classes of antihypertensives marketed. However, definitive conclusions about their roles in the management of hypertension are not possible until larger clinical trials assessing their efficacy and safety and comparing them with ACE inhibitors are completed.