ACE inhibitor- versus angiotensin II blocker-induced cough and angioedema

Lisinopril increases lung ACE2 levels and SARS-CoV-2 viral load and decreases inflammation but not disease severity in experimental COVID-19

COVID-19 causes more severe and frequently fatal disease in patients with pre-existing comorbidities such as hypertension and heart disease. SARS-CoV-2 virus enters host cells through the angiotensin-converting enzyme 2 (ACE2), which is fundamental in maintaining arterial pressure through the renin-angiotensin system (RAS). Hypertensive patients commonly use medications such as angiotensin-converting enzyme inhibitors (ACEi), which can modulate the expression of ACE2 and, therefore, potentially impact the susceptibility and severity of SARS-CoV-2 infection. Here we assessed whether treatment of ACE2-humanized (K18-hACE2) mice with the ACEi Lisinopril affects lung ACE2 levels and the outcome of experimental COVID-19. K18-hACE2 mice were treated for 21 days with Lisinopril 10 mg/kg and were then infected with 105 PFU of SARS-CoV-2 (Wuhan strain). Body weight, clinical score, respiratory function, survival, lung ACE2 levels, viral load, lung histology, and cytokine (IL-6, IL-33, and TNF-α) levels were assessed. Mice treated with Lisinopril for 21 days showed increased levels of ACE2 in the lungs. Infection with SARS-CoV-2 led to massive decrease in lung ACE2 levels at 3 days post-infection (dpi) in treated and untreated animals, but Lisinopril-treated mice showed a fast recovery (5dpi) of ACE2 levels. Higher ACE2 levels in Lisinopril-treated mice led to remarkably higher lung viral loads at 3 and 6/7dpi. Lisinopril-treated mice showed decreased levels of the pro-inflammatory cytokines IL-6 and TNF-α in the serum and lungs at 6/7dpi. Marginal improvements in body weight, clinical score and survival were observed in Lisinopril-treated mice. No differences between treated and untreated infected mice were observed in respiratory function and lung histology. Lisinopril treatment showed both deleterious (higher viral loads) and beneficial (anti-inflammatory and probably anti-constrictory and anti-coagulant) effects in experimental COVID-19. These effects seem to compensate each other, resulting in marginal beneficial effects in terms of outcome for Lisinopril-treated animals.

Targeting the renin-angiotensin signaling pathway in COVID-19: Unanswered questions, opportunities, and challenges

The role of the renin-angiotensin signaling (RAS) pathway in COVID-19 has received much attention. A central mechanism for COVID-19 pathophysiology has been proposed: imbalance of angiotensin converting enzymes (ACE)1 and ACE2 (ACE2 being the severe acute respiratory syndrome coronavirus 2 [SARS-CoV-2] virus "receptor") that results in tissue injury from angiotensin II (Ang II)-mediated signaling. This mechanism provides a rationale for multiple therapeutic approaches. In parallel, clinical data from retrospective analysis of COVID-19 cohorts has revealed that ACE inhibitors (ACEIs) or angiotensin receptor blockers (ARBs) may be beneficial in COVID-19. These findings have led to the initiation of clinical trials using approved drugs that target the generation (ACEIs) and actions (ARBs) of Ang II. However, treatment of COVID-19 with ACEIs/ARBs poses several challenges. These include choosing appropriate inclusion and exclusion criteria, dose optimization, risk of adverse effects and drug interactions, and verification of target engagement. Other approaches related to the RAS pathway might be considered, for example, inhalational administration of ACEIs/ARBs (to deliver drugs directly to the lungs) and use of compounds with other actions (e.g., activation of ACE2, agonism of MAS1 receptors, β-arrestin-based Angiotensin receptor agonists, and administration of soluble ACE2 or ACE2 peptides). Studies with animal models could test such approaches and assess therapeutic benefit. This Perspective highlights questions whose answers could advance RAS-targeting agents as mechanism-driven ways to blunt tissue injury, morbidity, and mortality of COVID-19.

Antihypertensive agents: a long way to safe drug prescribing in children

Recently updated clinical guidelines have highlighted the gaps in our understanding and management of pediatric hypertension. With increased recognition and diagnosis of pediatric hypertension, the use of antihypertensive agents is also likely to increase. Drug selection to treat hypertension in the pediatric patient population remains challenging. This is primarily due to a lack of large, well-designed pediatric safety and efficacy trials, limited understanding of pharmacokinetics in children, and unknown risk of prolonged exposure to antihypertensive therapies. With newer legislation providing financial incentives for conducting clinical trials in children, along with publication of pediatric-focused guidelines, literature available for antihypertensive agents in pediatrics has increased over the last 20 years. The objective of this article is to review the literature for safety and efficacy of commonly prescribed antihypertensive agents in pediatrics. Thus far, the most data to support use in children was found for angiotensin-converting enzyme inhibitors (ACE-I), angiotensin receptor blockers (ARB), and calcium channel blockers (CCB). Several gaps were noted in the literature, particularly for beta blockers, vasodilators, and the long-term safety profile of antihypertensive agents in children. Further clinical trials are needed to guide safe and effective prescribing in the pediatric population.

Losartan for the nephropathy of sickle cell anemia: A phase-2, multicenter trial

Nephropathy is a common and progressive complication of sickle cell anemia (SCA). In SCA mice, we found that hyperangiotensinemia in the absence of hypertension underlies nephropathy, and its downregulation by losartan, an angiotensin-II-receptor-1 blocker, reduced albuminuria and progression of nephropathy. Therefore, we performed a phase-2 trial of oral losartan, given for 6 months, to explore whether it reduced albuminuria in children and adults with SCA. Participants were allocated to groups defined by class of baseline urinary albumin-to-creatinine ratio (UACR): no albuminuria (NoA), microalbuminuria (MicroA), and macroalbuminuria (MacroA). The primary endpoint was a ≥25% reduction UACR from baseline. There were 32 evaluable participants (mean age 24 years; NoA = 14, MicroA = 12, MacroA = 6). The primary endpoint was met in 83% of the MacroA group (P < 0.0001) and 58% of the MicroA group (P < 0.0001). Median fold-change in UACR was -0.74 for MacroA and -0.46 for MicroA. In MacroA and MicroA, UACR classification improved in 50% but worsened in 11%. Urine osmolality and estimated glomerular filtration rate (eGFR) did not change significantly. Losartan was discontinued in three participants [leg cramps, N = 1; decline in eGFR >25% (142➝104 mL/minute/1.73 m² ), N = 1; rise in serum creatinine >50% (0.2➝0.3 mg/dL), N = 1]. Albuminuria was associated with diastolic dysfunction and impaired functional capacity, although cardiopulmonary status was unchanged after 6 months of losartan therapy. In summary, losartan decreased urinary albumin excretion in most participants with albuminuria. Those with macroalbuminuria had the greatest benefit. This study forms the basis for a phase-3, randomized, placebo-controlled trial of losartan for the nephropathy of SCA.

Fatal Acute Pancreatitis in a Patient Chronically Treated with Candesartan

Objective:

To summarize a case of acute pancreatitis in a patient receiving the angiotensin II receptor blocker (ARB) candesartan.

Case Summary:

A previously healthy 75-year-old white man presented with acute pancreatitis complicated by anuric renal failure, respiratory failure, circulatory collapse, and died within 24 hours despite resuscitation efforts. He had been receiving candesartan 32 mg/day for more than one year with no apparent adverse effects.

Discussion:

In recent years, angiotensin-converting enzyme (ACE) inhibitors have been linked with sporadic cases of acute pancreatitis. Recent case reports suggest a similar association between pancreatitis and the related drug class of ARBs. Animal data indicate that the renin–angiotensin system plays an important role in pancreatic hemodynamics and exocrine function and is activated in the setting of acute pancreatitis. Because both ARBs and ACE inhibitors affect angiotensin II, we hypothesize that a common pathophysiologic mechanism might apply to both ARB- and ACE inhibitor–induced pancreatitis.

Conclusions:

Although acute pancreatitis appears to be a rare complication of both ARBs and ACE inhibitors, the catastrophic outcome in this case mandates that clinicians be aware of this adverse effect. Further research into the role of the renin–angiotensin system in the pathogenesis of acute pancreatitis appears warranted.

Comparison of diagnostic evaluations for cough among initiators of angiotensin converting enzyme inhibitors and angiotensin receptor blockers

PURPOSE

Differential diagnostic evaluation associated with a drug may bias effect estimates because of an increased detection of preclinical outcomes. Persistent cough is a common side effect with angiotensin-converting enzyme inhibitors (ACEI), and we hypothesized that ACEI initiators would undergo more diagnostic evaluations, potentially leading to diagnosis of preclinical lung cancer. We compared the incidence of cough-related diagnostic evaluations and lung cancer among ACEI versus angiotensin receptor blockers (ARB) initiators.

METHODS

Using a 20% sample of Medicare claims 2007-2012, we identified initiators of ACEI or ARB, age 66-99 years. Incidence of diagnostic evaluation and lung cancer were compared using adjusted Cox models. Monthly probabilities of workup were compared using proportion differences.

RESULTS

There were 342 611 and 108 116 ACEI and ARB initiators, respectively. Monthly probability of chest X-rays ranged from minimum 4.7% to maximum 21.2% in the 6 months pre and post-initiation. Differences in incidence of diagnostic procedures in the 6 months after initiation were only minimal (chest X-rays hazard ratio (HR) = 1.12; 95% CI: 1.10-1.14), chest-MRI (0.86, 95% CI: 0.74-0.99), CT-scans (1.09, 95% CI: 0.99-1.18) or bronchoscopies (1.03, 95% CI: 0.83-1.29). Proportion differences for chest X-rays peaked in the month pre-initiation (8.4%, 95% CI: 8.1-8.6) but negligible thereafter. There was no difference in the incidence of lung cancer among ACEI versus ARB initiators (HR = 0.99, 95% CI: 0.84-1.16).

CONCLUSION

Results indicate minimal differential chest workup after ACEI versus ARB initiation and no difference in lung cancer incidence, but suggest differential workup in the month before the first recorded prescription. The latter may reflect drug use before the first observed pharmacy claim or increased workup before initiation of ACEI therapy. Copyright © 2016 John Wiley & Sons, Ltd.

An encounter with enalapril-induced resistant, life-threatening angioedema at rural health center in Botswana

Angioedema, a rare, potentially fatal and usually self-limiting adverse effect of therapy with enalapril, is always a challenging encounter for an intensive care specialist in a rural setup. Here, we present a 74-year-old female, who presented to the Emergency Department of Sekgoma Memorial Hospital, Serowe village, Botswana, with progressive swelling of her face, tongue and breathing difficulty just 2 days after starting tablet enalapril. She failed to respond to usual treatment with adrenaline, steroids, and H1-antihistaminic agent, but she responded well with intravenous fresh-frozen plasma infusion. This helped us manage a difficult airway situation in a less equipped rural health center.

ARBs and target organ protection

Recognition of the role of the renin-angiotensin-aldosterone system (RAAS) in initiating and maintaining hypertension prompted the development of drugs that disrupt the RAAS, notably the angiotensin-converting enzyme (ACE) inhibitors and, more recently, the angiotensin II receptor blockers (ARBs). This article focuses on the use of ARBs in hypertension management and reviews evidence emerging from clinical trials that ARBs offer target organ protection over and above their antihypertensive activity.

Vasopressor meets vasodepressor: The AT1-B2 receptor heterodimer

The AT1 receptor for the vasopressor angiotensin II is one of the most important drug targets for the treatment of cardiovascular diseases. Sensitization of the AT1 receptor system is a common feature contributing to the pathogenesis of many cardiovascular disorders but underlying mechanisms are not fully understood. More than a decade ago, evidence was provided for control of AT1R activation by heterodimerization with the B2 receptor for the vasodepressor peptide, bradykinin, a physiological counterpart of the vasoconstrictor angiotensin II. AT1-B2 receptor heterodimerization was shown to enhance AT1R-stimulated signaling under pathophysiological conditions such as experimental and human pregnancy hypertension. Notably, AT1R signal sensitization of patients with preeclampsia hypertension was attributed to AT1R-B2R heterodimerization. Vice versa, transgenic mice lacking the AT1-B2 receptor heterodimer due to targeted deletion of the B2R gene showed a significantly reduced AT1R-stimulated vasopressor response compared to transgenic mice with abundant AT1R-B2R heterodimerization. Biophysical methods such as BRET and FRET confirmed those data by demonstrating efficient AT1-B2 receptor heterodimerization in transfected cells and transgenic mice. Recently, a study on AT1R-specific biased agonism directed the focus to the AT1-B2 receptor heterodimer again. The β-arrestin-biased [Sar1,Ile4,Ile8]-angiotensin II promoted not only the recruitment of β-arrestin to the AT1R but also stimulated the down-regulation of the AT1R-associated B2 receptor by co-internalization. Thereby specific targeting of the AT1R-B2R heterodimer became feasible and could open the way to a new class of drugs, which specifically interfere with pathological angiotensin II-AT1 receptor system activation.

Economic evaluations of angiotensin-converting enzyme inhibitors and angiotensin II receptor blockers in type 2 diabetic nephropathy: a systematic review

Background

Structured comparison of pharmacoeconomic analyses for ACEIs and ARBs in patients with type 2 diabetic nephropathy is still lacking. This review aims to systematically review the cost-effectiveness of both ACEIs and ARBs in type 2 diabetic patients with nephropathy.

Methods

A systematic literature search was performed in MEDLINE and EMBASE for the period from November 1, 1999 to Oct 31, 2011. Two reviewers independently assessed the quality of the articles included and extracted data. All cost-effectiveness results were converted to 2011 Euros.

Results

Up to October 2011, 434 articles were identified. After full-text checking and quality assessment, 30 articles were finally included in this review involving 39 study settings. All 6 ACEIs studies were literature-based evaluations which synthesized data from different sources. Other 33 studies were directed at ARBs and were designed based on specific trials. The Markov model was the most common decision analytic method used in the evaluations. From the cost-effectiveness results, 37 out of 39 studies indicated either ACEIs or ARBs were cost-saving comparing with placebo/conventional treatment, such as amlodipine. A lack of evidence was assessed for valid direct comparison of cost-effectiveness between ACEIs and ARBs.

Conclusion

There is a lack of direct comparisons of ACEIs and ARBs in existing economic evaluations. Considering the current evidence, both ACEIs and ARBs are likely cost-saving comparing with conventional therapy, excluding such RAAS inhibitors.

Efficacy and safety of valsartan in hypertensive Taiwanese patients: post-marketing surveillance study

OBJECTIVE

To evaluate the efficacy and safety of valsartan in Taiwanese patients with essential hypertension.

METHODS

This 12-week multi-center, open-label, observational, post-marketing surveillance study enrolled 2046 hypertensive patients who were prescribed valsartan 80 or 160 mg as monotherapy or in combination with other antihypertensives based on clinical judgment. The primary endpoint was the incidence rate of dizziness with valsartan 160 mg monotherapy or combination therapy at Week 4. Secondary endpoints included the blood-pressure-lowering efficacy and the overall safety and tolerability of valsartan at Weeks 4 and 12.

RESULTS

The monotherapy and combination groups had comparable baseline characteristics. At Week 4, monotherapy was found non-inferior to combination for incidence rate of dizziness (monotherapy, 9.25%; combination, 10%; difference in incidence of dizziness, 0.75%; 95% CI - 0.61% to 2.12%; non-inferiority margin, -1.33%;WaldTest approach). Greater blood pressure (BP) reduction was noted atWeek 12 than atWeek 4.The antihypertensive effect was greater with combination therapy and the 160-mg dose. BP control (systolic <140 mmHg or diastolic <90 mmHg) was achieved in 80-90% patients.Valsartan was well tolerated; most commonly reported adverse events included dizziness, headache, constipation and cough.

CONCLUSION

Valsartan is an effective treatment option for essential hypertension in Taiwanese patients.

Differences between zofenopril and ramipril, two ACE inhibitors, on cough induced by citric acid in guinea pigs: role of bradykinin and PGE2

Dry and persistent cough is one of the commonest side effects experienced by patients treated with angiotensin-converting enzyme (ACE) inhibitors for the therapy of hypertension and congestive heart failure. The present study investigated the effect of zofenopril and ramipril on cough induced by citric acid in guinea pig and the involvement of bradykinin (BK) and prostaglandin E2 (PGE2) in mediating the responses of these drugs. Zofenopril (10 mg/kg) or ramipril (3-10 mg/kg), which is threefold more potent than zofenopril, on a mg basis, in lowering blood pressure, was orally administered daily in drinking water for 2 weeks. At the end of this period, aerosol of citric acid solution (0.1 M) was performed and the number of cough counted for 10 min. The role of the kinin B(2) receptor was also investigated. BK and PGE2 levels in the bronchoalveolar lavage (BAL) fluid were measured after repeated oral treatment with zofenopril or ramipril (10 mg/kg). Ramipril (3-10 mg/kg) increased citric acid-induced cough by 40% and 60%, respectively, as compared to the vehicle control group (15.0 ± 1.8), while zofenopril (10 mg/kg) was without effect. The enhancement of citric acid-induced cough caused by ramipril (10 mg/kg) was reduced by the kinin B(2) receptor antagonist MEN16132 (0.25 mg/kg ip). BK and PGE2 levels in the BAL fluid were increased, in comparison to the control group, after ramipril treatment, while they were unchanged after zofenopril administration. Zofenopril, contrary to ramipril, did not affect either citric acid-induced cough in the guinea pigs or BK and PGE2 production in the airways.

Efficacy of combination therapy with telmisartan plus amlodipine in patients with poorly controlled hypertension

There is accumulating evidence that blood pressure (BP) control significantly reduces the risk of future cardiovascular events in patients with essential hypertension. However, strict BP control is often difficult to maintain, and half of hypertensive patients fail to attain BP goals on single-drug therapy. Therefore, current guidelines recommend combinations of drugs that have complimentary mode of actions for treatment of patients with moderate hypertension. In this study, we examined in hypertensive patients uncontrolled by the combination treatment with 5 mg amlodipine plus 80 mg valsartan or 8 mg candesartan whether additional BP lowering could be achieved by switching to 5 mg amlodipine plus 40 mg telmisartan. Forty-seven patients with essential hypertension who failed to achieve a target BP level by the treatment of 5 mg amlodipine plus 80 mg valsartan or 8 mg candesartan for at least 2 months were enrolled. Replacement of valsartan or candesartan by telmisartan showed a significant reduction in both mean clinic systolic and diastolic BP at 4, 8 and 12 weeks; BP level decreased from 143.7/82.3 mmHg at baseline to 135.4/77.5 mmHg at 12 weeks. Furthermore, in 8 patients of valsartan group, switching to telmisartan significantly reduced central BP by 11.8 mmHg. Our present study suggests that combination therapy with telmisartan plus amlodipine may be more beneficial than valsartan or candesartan plus amlodipine treatment for controlling brachial and central BP, which could lead to more favorable cardiovascular outcomes with this drug combinations.

Efficacy and safety of angiotensin II receptor type 1 antagonists in children and adolescents

Our purpose was to evaluate the effects of angiotensin II receptor type 1 antagonists (ARAs) in children and adolescents with hypertension or/and several kinds of nephropathies on blood pressure (BP) and proteinuria and to evaluate related safety issues. Data sources were Medline, Embase, The Cochrane Library, BIOSIS Previews, contact with investigators and manufacturers, personal bibliography of the lead author, and manual searches. We selected randomized controlled trials (RCTs), uncontrolled trials, and case series investigating ARAs in children and adolescents, as well as case reports about adverse events and the embryotoxic effects of ARAs in children. In four RCTs with 698 individuals, mean systolic blood pressure (BP) decreased by 10.5 mmHg [95% confidence interval (CI) 9.8-11.2] and mean diastolic BP by 6.4 mmHg (95% CI 5.8-7.0). Proteinuria decreased by 30-64% (range) in two RCTs and four case series. Safety data were comparable with adult safety data. ARAs can be considered effective and safe in lowering BP and proteinuria in the pediatric age group. The correlation between the surrogate parameters BP and proteinuria with clinical endpoints is documented to a large degree. The evidence is based on RCTs and also on lower evidence levels, such as case series. In some conditions, RCTs in children are not feasible. Registers could provide more evidence in the future.

Challenges of therapeutic substitution of drugs for economic reasons: focus on CVD prevention

BACKGROUND

Healthcare systems throughout the world are under increasing pressure to control and minimise costs. The substitution of initially-prescribed drugs with cheaper equivalents is an obvious option which presents a rapid and visible means to reduce these costs. Whether the substitution improves patient and/or population outcomes must be appraised and this paper highlights the conditions under which therapeutic substitution may require additional thought and consideration.

SCOPE

In this paper, some of the medical evidence and the regulatory environment for and against the three types of therapeutic substitution - generic, within-class and between-class - are discussed. This article is not an exhaustive review of the literature, but captures some of the key clinical, pharmacological, economic, policy and ethical issues regarding generic and therapeutic substitution. Search criteria of the most commonly used terms, i.e. therapeutic substitution, switching, interchange, and bioequivalence, were applied to Embase, PubMed and Google Scholar to identify relevant publications.

FINDINGS

Although population studies support therapeutic substitution in principle, there is evidence that substitution may not always result in therapeutic equivalence in individual patients, with the consequent potential for greater risks of decreased efficacy and/or increased safety concerns. Factors such as patient choice and therapeutic equivalence also play an important role in the effectiveness of the treatment and overall management of the patient. The pan-European regulatory environment provides another contradiction, encouraging widespread cost containment through reduction in drug acquisition costs, while simultaneously promoting an increased role for patients in defining and managing their own treatment.

CONCLUSIONS

There is a strong rationale for careful management in some patients with cardiovascular disease. Treatment decisions should be transparent and based on strong clinical evidence. If not, drug substitution on economic grounds alone cannot be considered to be in the individual patient's interest and is therefore unethical.

Metabolic effects of telmisartan and irbesartan in type 2 diabetic patients with metabolic syndrome treated with rosiglitazone

BACKGROUND AND OBJECTIVE

Angiotensin II receptor blockers represent a class of effective and well-tolerated orally active antihypertensive drugs in the general hypertensive population and in diabetic patients. The aim of our study was to investigate the metabolic effects of telmisartan and irbesartan in diabetic subjects treated with rosiglitazone.

METHODS

We evaluated 188 type 2 diabetic patients with metabolic syndrome. All patients took a fixed dose of 4 mg rosiglitazone/day. We administered 40 mg telmisartan/day or 150 mg irbesartan/day and evaluated their body mass index, glycosylated haemoglobin (HbA(1c)), fasting plasma glucose (FPG), fasting plasma insulin (FPI), homeostasis model assessment-index (Homa-IR), total cholesterol (TC), low density lipoprotein-cholesterol (LDL-C), high density lipoprotein-cholesterol, triglycerides, systolic blood pressure, diastolic blood pressure, adiponectin and resistin during 12 months of this treatment.

RESULTS AND DISCUSSION

In addition to a comparable antihypertensive effect for telmisartan and irbesartan after 6 and 12 months, both treatments were associated with a significant reduction in TC and LDL-C plasma levels compared with baseline. After 6 months of treatment, only the telmisartan group experienced a significant improvement in (HbA(1c)), FPG, Homa-IR, adiponectin and resistin compared with the baseline values, whereas both drug regimens were associated with a significant improvement in these parameters after 12 months. However, the improvements observed in the telmisartan group were significantly larger than that noted in the irbesartan group after 12 months of treatment. FPI significantly decreased only after 12 months of treatment in both groups, but again, the reduction was significantly larger in the telmisartan-treated subjects.

CONCLUSIONS

Telmisartan seemed to improve glycaemic and lipid control and metabolic parameters of the metabolic syndrome better than irbesartan. These differences could be relevant in the choice of therapy for this condition and diabetes.

Hypertension‐Related Morbidity and Mortality in African Americans—Why We Need to Do Better

Almost one third of adults in the United States have hypertension. Prevalence data among different racial or ethnic groups indicate that a disproportionate number of African Americans have hypertension compared with non-Hispanic whites and Mexican Americans. Earlier onset of high blood pressure and greater severity of hypertension contribute to a greater burden of hypertensive target organ damage in African Americans and may be a factor in the shorter life expectancy of this population compared with white Americans. There is a clear need for improved management of hypertension in African Americans via therapeutic lifestyle interventions and pharmacotherapy. While there is some evidence that particular antihypertensive agent classes provide blood pressure-lowering advantages over others, there is no support for withholding agents of any one class. When given as monotherapy, diuretics and calcium channel blockers may be relatively more effective in lowering blood pressure in African Americans than beta blockers, angiotensin-converting enzyme inhibitors, and angiotensin II receptor blockers. However, when combined with a diuretic, African Americans respond as well to these agents as other racial groups. Combination therapy using antihypertensive agents with differing modes of action provides additive antihypertensive efficacy and is well tolerated. Recent guidelines recommend combination therapy as the standard of care for patients with significant blood pressure elevation, especially those with diabetes mellitus and renal disease. These comorbidities are more common in African Americans and indicate the potential need for initial therapy with more than one agent or a combination of agents in one pill.

Building on the Specialist's Antihypertensive Treatment Recommendation: It's Just the Beginning

Patients with established cardiovascular disease are a top priority for preventive medicine. Evidence from clinical trials supports the merits of aggressive risk reduction therapies in survivors of an acute event. Improving their cardiovascular risk factor profile prolongs survival, reduces the incidence of recurrent atherosclerotic events, and improves quality of life. Blood pressure (BP) control is an essential component of cardiovascular disease secondary prevention programs; however, many patients are not receiving adequate antihypertensive therapy to meet their BP goal. By building on the specialist's discharge antihypertensive prescription, primary care physicians are ideally positioned to assume responsibility for ensuring BP goals are achieved and maintained over the long term in patients who have survived an acute event. Current hypertension management guidelines define appropriate BP goals and incorporate clear advice on how these goals can be met. BP should be lowered slowly and carefully through lifestyle modifications and pharmacologic therapy. Antihypertensive treatment should be given according to guidelines for primary prevention, although specific antihypertensive classes are indicated for initial use in post-myocardial infarction and post-stroke patients. In many cases, BP goal attainment will require the use of combination therapy with two or more drugs from different classes. With the availability of effective and safe antihypertensive drug therapies, including fixed-dose combinations, a BP goal of <140/90 mm Hg should be achievable in most patients.

Brief review: angiotensin converting enzyme inhibitors and angioedema: anesthetic implications

PURPOSE

Angiotensin converting enzyme inhibitors (ACEIs) are a group of drugs used to treat hypertension and heart failure, with additional benefits, such as cardiovascular and renal protection, in patients with diabetes. However, angioedema as a complication of ACEI therapy is under-recognized. As there are important implications for anesthesiologists and emergency medicine physicians, a review was undertaken to document the scope of the problem of ACEI-induced angioedema..

METHODS

A review of the published literature (identified by searching Medline, EMBASE and CINAHL) was undertaken, addressing the clinical uses of ACEIs and the incidence, risk factors, pathophysiology, clinical presentation and management of angioedema associated with the use of these drugs.

PRINCIPAL FINDINGS

The incidence of ACEI related angioedema has increased from 0.1-0.2% to 1% over the last decade. Patients who are receiving ACEIs are predisposed to developing angioedema which may be triggered by trauma, airway instrumentation, infection, and irritant fumes, particularly in those who are at increased risk. Cases of acute facial and airway oedema, due to ACEI drug administration, may be misdiagnosed as an anaphylactic reaction, and the association with ACEIs may be ignored. Some cases of intraoperative and postoperative airway edema may be precipitated by airway instrumentation in patients receiving ACEI drugs. The severity of airway compromise ranges from mild facial edema to severe laryngeal or subglottic edema which may prove life-threatening.

CONCLUSION

In view of the widespread clinical indications and ever-increasing use of ACEI drugs, the potentially life-threatening adverse reaction of ACEI-associated angioedema, and its treatment, must be recognized by anesthesiologists and all clinicians involved in airway management.

Efficacy of Angiotensin Receptor Blockers in Cardiovascular Disease

The cardiovascular continuum describes the progression of pathophysiologic events from cardiovascular risk factors to symptomatic cardiovascular disease (CVD) and life-threatening events. Pharmacologic intervention early in the continuum may prevent or slow CVD development and improve quality of life. The renin-angiotensin-aldosterone system (RAAS) is central to the pathophysiology of CVD at many stages of the continuum. Numerous clinical trials of angiotensin converting enzyme (ACE) inhibitors and angiotensin receptor blockers (ARBs) have shown that RAAS blockade provides benefits to patients across the continuum. ARBs are as effective as ACE inhibitors in the treatment of hypertension; however tolerability and adherence to therapy appear to be improved with ARBs. Large clinical trials have shown that ARBs may provide therapeutic benefits beyond blood pressure control in patients with diabetes, heart failure or at risk of heart failure following a myocardial infarction. In addition, ARBs have been shown to provide protective effects in patients with impaired renal function or left ventricular hypertrophy. Additional clinical trials are ongoing to further characterize the role of ARBs in CVD management.

Ambulatory blood pressure comparison of the anti-hypertensive efficacy of fixed combinations of irbesartan/hydrochlorothiazide and losartan/hydrochlorothiazide in patients with mild-to-moderate hypertension

This study examined whether the greater anti-hypertensive efficacy of irbesartan monotherapy over losartan monotherapy extends to the respective fixed-dose combinations with hydrochlorothiazide (HCTZ) in patients with mild-to-moderate hypertension. Patients were treated with either irbesartan 150 mg/HCTZ 12.5 mg or losartan 50 mg/HCTZ 12.5 mg over a 4-week period. Twenty-four hour daytime and night-time mean blood pressure (BP), BP load and duration of action were assessed using ambulatory BP monitoring. Both treatment regimens significantly reduced BP from baseline for all efficacy variables assessed. A significant difference was noted in adjusted mean changes from baseline in 24-h ambulatory diastolic BP with irbesartan/HCTZ versus losartan/HCTZ. Reduction in diastolic load was significantly greater with irbesartan/HCTZ than with losartan/HCTZ as was mean ambulatory systolic BP during the last 4 h of the dosing interval. Both regimens were well tolerated, with no significant differences in terms of adverse event profile observed. Irbesartan 150 mg/HCTZ 12.5 mg resulted in greater reductions in ambulatory BP than losartan 50 mg/HCTZ 12.5 mg.

Pharmacoeconomics of angiotensin II antagonists in type 2 diabetic patients with nephropathy: implications for decision making

Angiotensin II receptor antagonists (angiotensin II receptor blockers; ARBs) are a class of antihypertensive drugs that are generally considered comparable to ACE inhibitors in the prevention of heart and kidney failure. However, these two classes of agents do interfere in different stages of the renin-angiotensin system. In patients with type 2 diabetes mellitus, advantages for ARBs over conventional (non-ACE inhibitor) therapy on progression from micro- to macroalbuminuria and overt nephropathy and end-stage renal disease have been shown in clinical trials. In patients with type 2 diabetes and end-stage renal disease, the need for dialysis and/or transplantation results in the use of major healthcare resources. This paper reviews the available economic evidence on treatment with ARBs in type 2 diabetic patients with advanced renal disease.Within-trial analytic and Markov model economic evaluations of the RENAAL (Reduction of Endpoint in Non-insulin dependent diabetes mellitus with Angiotensin II Antagonist Losartan), IDNT (Irbesartan Diabetic Nephropathy Trial) and IRMA (IRbesartan in type 2 diabetes with MicroAlbuminuria)-2 studies suggest that treatment with ARBs in patients with type 2 diabetes with overt or incipient nephropathy confers health gains and net cost savings compared with conventional (non-ACE inhibitor) therapy. For reimbursement and reference pricing decisions, there is a need for a head-to-head comparison of an ACE inhibitor with ARBs to model all possible costs and effects of ACE inhibitors and ARBs. This will result in a proper pharmacoeconomic outcome, where both types of drugs can be compared for healthcare decisions.

Telmisartan and Irbesartan Therapy in Type 2 Diabetic Patients Treated with Rosiglitazone: Effects on Insulin-Resistance, Leptin and Tumor Necrosis Factor-.ALPHA

The aim of our study was to investigate the metabolic effect of telmisartan and irbesartan in subjects treated with rosiglitazone, a well-known insulin-sensitizing drug, in order to clarify the direct metabolic effects of the two former drugs. Patients were enrolled, evaluated, and followed at 3 Italian centers. We evaluated 188 type 2 diabetic patients with metabolic syndrome (94 males and 94 females in total; 49 males and 46 females, aged 56+/-5, treated with telmisartan; and 45 males and 48 females, aged 55+/-4, treated with irbesartan). All had been diabetic for at least 6 months, and glycemic control by the maximum tolerated dietary changes and maximum tolerated dose of oral hypoglycemic agents had been attempted and failed in all cases. All patients took a fixed dose of rosiglitazone, 4 mg/day. We administered telmisartan (40 mg/day) or irbesartan (150 mg/day) in a randomized, controlled, double-blind clinical manner. We evaluated body mass index (BMI), glycemic control (HbA1c fasting plasma glucose and insulin levels [FPG, and FPI, respectively], and homeostasis model assessment [HOMA] index), lipid profile (total cholesterol [TC], low density lipoprotein-cholesterol [LDL-C], high density lipoprotein-cholesterol [HDL-C], and triglycerides [TG]), systolic and diastolic blood pressure (SBP and DBP), tumor necrosis factor-alpha (TNF-alpha), and leptin during the 12 months of this treatment. No BMI change was observed after 6 or 12 months in either group. Significant decreases in HbAlc and FPG were observed after 6 months in the telmisartan group, and after 12 months in both groups. The decrease in HbA1c and FPG at 12 months was statistically significant only in the telmisartan group. A significant decrease in FPI was observed at 12 months in both groups, and this decrease was significantly greater in the telmisartan group. Significant decreases in the HOMA index were observed at 6 and 12 months in both groups, and the decrease in the HOMA index after 12 months was significantly greater in the telmisartan group than in the irbesartan group. Significant changes in SBP, DBP, TC, and LDL-C were observed after 6 and 12 months in both groups. Significant decreases in TNF-alpha and leptin levels were observed after 6 months in the telmisartan group, and after 12 months in both groups. In conclusion, in this study of patients with type 2 diabetes mellitus and metabolic syndrome, telmisartan seemed to result in a greater improvement in glycemic and lipid control and metabolic parameters related to metabolic syndrome compared to irbesartan. These observed metabolic effects of different angiotensin type 1 receptor blockers could be relevant when choosing a therapy to correct metabolic derangement of patients affected by metabolic syndrome and diabetes.

Angiotensin-Converting Enzyme Inhibitor-Induced Cough

BACKGROUND

A dry, persistent cough is a well-described class effect of the angiotensin-converting enzyme (ACE) inhibitor medications. The mechanism of ACE inhibitor-induced cough remains unresolved, but likely involves the protussive mediators bradykinin and substance P, agents that are degraded by ACE and therefore accumulate in the upper respiratory tract or lung when the enzyme is inhibited, and prostaglandins, the production of which may be stimulated by bradykinin.

METHODS

Data for this review were obtained from a National Library of Medicine (PubMed) search, which was performed in May 2004, of the literature published in the English language from 1985 to 2004, using the search terms "angiotensin-converting enzyme," "angiotensin converting enzyme inhibitors," and "cough."

RESULTS

The incidence of ACE inhibitor-induced cough has been reported to be in the range of 5 to 35% among patients treated with these agents. However, a much lower incidence has been described in studies of patients presenting for the evaluation of chronic cough. The onset of ACE inhibitor-induced cough ranges from within hours of the first dose to months after the initiation of therapy. Resolution typically occurs within 1 to 4 weeks after the cessation of therapy, but cough may linger for up to 3 months. The only uniformly effective treatment for ACE inhibitor-induced cough is the cessation of treatment with the offending agent. The incidence of cough associated with therapy with angiotensin-receptor blockers appears to be similar to that of the control drug. In a minority of patients, cough will not recur after the reintroduction of ACE inhibitor therapy.

CONCLUSIONS

In a patient with chronic cough, ACE inhibitors should be considered as wholly or partially causative, regardless of the temporal relation between the initiation of ACE inhibitor therapy and the onset of cough. Although the cessation of therapy is the only uniformly effective treatment for ACE inhibitor-induced cough, some pharmacologic agents have been shown to attenuate the cough.

ACE2: A novel therapeutic target for cardiovascular diseases

Hypertension afflicts over 65 million Americans and poses an increased risk for cardiovascular morbidity such as stroke, myocardial infarction and end-stage renal disease resulting in significant mortality. Overactivity of the renin-angiotensin system (RAS) has been identified as an important determinant that is implicated in the etiology of these diseases and therefore represents a major target for therapy. In spite of the successes of drugs inhibiting various elements of the RAS, the incidence of hypertension and cardiovascular diseases remain steadily on the rise. This has lead many investigators to seek novel and innovative approaches, taking advantage of new pathways and technologies, for the control and possibly the cure of hypertension and related pathologies. The main objective of this review is to forward the concept that gene therapy and the genetic targeting of the RAS is the future avenue for the successful control and treatment of hypertension and cardiovascular diseases. We will present argument that genetic targeting of angiotensin-converting enzyme 2 (ACE2), a newly discovered member of the RAS, is ideally poised for this purpose. This will be accomplished by discussion of the following: (i) summary of our current understanding of the RAS with a focus on the systemic versus tissue counterparts as they relate to hypertension and other cardiovascular pathologies; (ii) the newly discovered ACE2 enzyme with its physiological and pathophysiological implications; (iii) summary of the current antihypertensive pharmacotherapy and its limitations; (iv) the discovery and design of ACE inhibitors; (v) the emerging concepts for ACE2 drug design; (vi) the current status of genetic targeting of the RAS; (vii) the potential of ACE2 as a therapeutic target for hypertension and cardiovascular disease treatment; and (viii) future perspectives for the treatment of cardiovascular diseases.

Effects of Doxazosin and Irbesartan on Blood Pressure and Metabolic Control in Patients with Type 2 Diabetes and Hypertension

The objective of this trial was to compare the metabolic effects of long-term treatment with doxazosin to those of irbesartan in patients with type 2 diabetes and hypertension. We evaluated 96 hypertensive diabetic patients who were randomized to 12 months of double-blind treatment with doxazosin 4 mg/d or irbesartan 300 mg/d. At the end of the study, systolic and diastolic blood pressure (SBP and DBP) were significantly reduced from 152 to 140 mm Hg and from 97 to 87 mm Hg, respectively, with doxazosin (P < 0.01). SBP and DBP were reduced from 150 to 134 mm Hg and from 94 to 83 mm Hg, respectively, with irbesartan (P < 0.01). Irbesartan had significantly better antihypertensive efficacy than doxazosin (P < 0.05). Doxazosin had the greatest effect on glucose metabolism and lipid parameters, with significant (P </= 0.05) reductions observed at study end compared with baseline in glycosylated hemoglobin, fasting plasma glucose, fasting plasma insulin, total cholesterol, low-density lipoprotein cholesterol, high-density lipoprotein cholesterol, triglycerides, and Homeostasis Model Assessment Index. In conclusion, both doxazosin and irbesartan reduced BP during long-term treatment, but not to recommended levels, and doxazosin had the more beneficial effect on glucose metabolism and lipid profile.

Treatment of systolic hypertension: spotlight on recent studies with angiotensin II antagonists

Systolic blood pressure has a continuous, graded, strong, independent, and aetiologically significant relationship to mortality from coronary heart disease, stroke, and all cardiovascular diseases, as well as to all-cause mortality and life expectancy. Angiotensin II (AII) may be intimately involved in the pathogenesis of systolic hypertension through multiple mechanisms, including decreasing the elastin content and increasing the collagen content of the arterial wall, thickening and fibrotic remodelling of the vascular intima, and proliferating smooth muscle cells in the arterial wall, resulting in increased thickness, stiffening, and partial loss of contractility. AII antagonists may therefore offer hitherto unrecognized benefits (independent of blood pressure) on age-related vascular damage and provide particular benefits in patients with systolic hypertension. Recent evidence has demonstrated that losartan offers cardiovascular outcomes benefits in isolated systolic hypertension (ISH) associated with an excellent tolerability profile. This, in patients with ISH, AII antagonists more facilitate systolic BP control, providing cardiovascular protection and offering an excellent risk-benefit profile.

Rationale for the use of angiotensin ii receptor blockers in patients with left ventricular dysfunction (part I of II)

Almost 5 million individuals in the United States are diagnosed with chronic heart failure (HF), and the prevalence is increasing. Angiotensin-converting enzyme (ACE) inhibitors and beta blockers, neurohormonal antagonists that block the renin-angiotensin system (RAS) and the sympathetic nervous system, respectively, have been shown in clinical trials to reduce morbidity and mortality in patients with HF, and these therapies are now integral components of standard HF treatment. Yet, morbidity and mortality rates in HF remain unacceptably high, and the limitations of current standard therapies are becoming increasingly apparent. About 10% of patients with HF are unable to tolerate ACE inhibitors, often because of cough. In addition, ACE inhibition may not completely block the RAS because angiotensin II, the main end product of the RAS, can be generated via non-ACE enzymatic pathways. Angiotensin II receptor blockers (ARBs) may exert more complete RAS blockade than ACE inhibitors by interfering with the binding of angiotensin II at the receptor level, regardless of the enzymatic pathway of production. They are also better tolerated than ACE inhibitors and have been shown to improve symptoms and function in clinical trials in patients with HF. These factors provide a strong rationale for the study of the clinical effects of ARBs in patients with HF.

Effects of telmisartan compared with eprosartan on blood pressure control, glucose metabolism and lipid profile in hypertensive, type 2 diabetic patients: a randomized, double-blind, placebo-controlled 12-month study

We evaluated the antihypertensive activity, glucose homeostasis and plasma lipid profile in patients with mild hypertension and type 2 diabetes mellitus treated by diet and exercise, and not in receipt of oral hyperglycemics, following 12-month treatment with either telmisartan or eprosartan. In this double-blind, placebo-controlled trial, 119 patients with mild essential hypertension (diastolic blood pressure [DBP] 91-104 mmHg) and type 2 diabetes were divided into three groups and randomized to receive once-daily telmisartan 40 mg, eprosartan 600 mg, or placebo for 12 months. At enrollment, patients were advised on diet (1,400-1,600 kcal/day) and exercise (physical aerobics on a bicycle for at least 30 min on 4 days each week). Compared with baseline, a significant reduction (p<0.01) in seated trough systolic blood pressure (SBP) was detected after 12-month treatment with either telmisartan or eprosartan. Seated trough DBP was also reduced by telmisartan (p<0.01) and eprosartan (p<0.05); the antihypertensive effect of telmisartan was significantly superior (p<0.05). No change in body mass index or glucose metabolism was observed with either active treatment, or with placebo. Telmisartan, but not eprosartan, significantly improved plasma total cholesterol (p<0.01), low-density lipoprotein cholesterol (p<0.01) and triglycerides (p<0.05) compared with eprosartan. In conclusion, 12-month telmisartan treatment produced a significantly greater reduction in DBP than eprosartan and significantly improved plasma lipids. The improvement could be due to varying pharmacokinetic/pharmacodynamic properties of telmisartan compared with eprosartan, even if it is not clear about the relationship between angiotensin-II receptor blockade and 3-hydroxy-3-methylglutaryl-coenzyme A reductase inhibition.

Angiotensin II receptor antagonists alone and combined with hydrochlorothiazide: potential benefits beyond the antihypertensive effect

Angiotensin II receptor antagonists (angiotensin receptor blockers; ARBs) and thiazide diuretics have an accepted place in the management of hypertension. Most patients require combination therapy with two or more drugs to adequately control blood pressure to targets recommended by European and international guidelines. ARBs and the thiazide diuretic hydrochlorothiazide have complementary modes of action. Fixed-dose combinations of an ARB and low-dose hydrochlorothiazide provide a convenient and effective treatment option for patients who do not achieve blood pressure targets on monotherapy, without compromising the placebo-like tolerability of ARBs. In Europe, fixed-dose combinations with hydrochlorothiazide currently are available for the ARBs candesartan, eprosartan, irbesartan, losartan, telmisartan, and valsartan. Recently, a number of studies have focused on the use of ARBs in monotherapy and in combination therapy, in conditions including congestive heart failure, post-myocardial infarction management, hypertension with cardiovascular risk factors, and diabetic and non-diabetic nephropathy. Evidence from these studies suggests a beneficial role beyond the antihypertensive effect of these therapies in providing protection against cardiovascular, renovascular, and cerebrovascular events.

Transepithelial Transport of Telmisartan in Caco-2 Monolayers

Telmisartan is the most recently marketed angiotensin II type 1 receptor antagonist. Drug-drug interactions involving transporters can directly affect the therapeutic safety and efficacy of many important drugs. In clinical practice, telmisartan is coadministered with many kinds of drugs. However, little is known about the contribution of transporters to the intestinal transport of telmisartan. The aim of this study was to determine the transport mechanism of telmisartan across intestinal epithelial cells. In the presence of an inwardly directed proton gradient, the apical-to-basal transport of telmisartan was greater than basal-to-apical transport. Thus, we focused on the uptake mechanism of telmisartan across brush-border membranes. The uptake of telmisartan by Caco-2 cells was shown to be energy- and proton-dependent. Although some monocarboxylates inhibited the uptake of telmisartan, L-lactic acid, which is a typical substrate of the monocarboxylate transporter (MCT) 1-MCT4, did not affect the uptake of telmisartan. Preloading of acetic acid enhanced the uptake of telmisartan, showing a trans-stimulation effect. These results suggest that the carrier-mediated transport system is involved in the uptake of telmisartan by Caco-2 cells and that the apical-localized transport system is similar to MCTs, but not MCT1-MCT4. It is possible that telmisartan reduce the absorption of coadministered drugs by sharing the MCTs. Since MCTs have an important role in the intestinal absorption of pharmacologically active compounds, it is important to be aware of the potential of telmisartan-drug interactions involving MCTs and to act in order to prevent undesirable and harmful consequences.

Comparison of the effects of telmisartan and nifedipine gastrointestinal therapeutic system on blood pressure control, glucose metabolism, and the lipid profile in patients with type 2 diabetes mellitus and mild hypertension: a 12-month, randomized, double-blind study

BACKGROUND

Angiotensin receptor blockers (ARBs) provide effective blood pressure control. Whereas none of the ARBs appear to affect glucose homeostasis, some ARBs have been associated with a decrease in cholesterolemia.

OBJECTIVE

This study was conducted to evaluate blood pressure control glucose homeostasis, and the plasma lipid profile in patients with type 2 diabetes mellitus and mild hypertension during 12 months of treatment with the ARB telmisartan or nifedipine gastrointestinal therapeutic system (GITS).

METHODS

In this double-blind trial, patients taking oral hypoglycemic agents were randomized to receive telmisartan 40 mg or nifedipine GITS 20 mg once daily for 12 months. At the time of enrollment, patients were given advice on diet (1400-1600 kcal/d) and exercise (stationary bicycle for > or =30 min, 4 d/wk). Assessments of systolic blood pressure (SBP), diastolic blood pressure, body mass index (BMI), fasting plasma glucose concentrations, glycosylated hemoglobin, fasting plasma insulin concentrations, the homeostasis model assessment of insulin resistance, and the lipid profile were performed at baseline and after 6 and 12 months of treatment.

RESULTS

One hundred sixteen patients were divided into 2 age- and sex-matched treatment groups (58 men, 58 women; mean [SD] age, 52.5 [5] years). All patients were in good general health at baseline; had achieved adequate glycemic control with diet and oral hypoglycemic agents; were taking antihypercholesterolemic drugs; and had no evidence of macroangiopathy, microalbuminuria, or neuropathy. There were significant reductions from baseline in seated trough SBP after 12 months of treatment with both telmisartan and nifedipine GITS (from 139 [4] to 132 [4] mm Hg and from 140 [4] to 130 [4] mm Hg, respectively; both, P < 0.01). No change in BMI or glucose metabolism was observed with either treatment. After 12 months, there were significant improvements in concentrations of total cholesterol (TC) and low-density lipoprotein cholesterol (LDL-C) with telmisartan (-9% and -11.5%, respectively; both, P < 0.01) compared with nifedipine GITS (-2% and -1.5%).

CONCLUSIONS

In this selected sample of patients with type 2 diabetes and mild hypertension, both telmisartan and nifedipine GITS produced significant reductions in blood pressure. Telmisartan was associated with a slight but statistically significant improvement in plasma TC and LDL-C concentrations compared with nifedipine GITS.

Irbesartan: a review of its use in hypertension and in the management of diabetic nephropathy

Irbesartan (Avapro, Aprovel) is a potent and selective angiotensin II subtype 1 receptor antagonist indicated for use in patients with hypertension, including those with type 2 diabetes mellitus and nephropathy. Once-daily administration of irbesartan provided 24-hour control of blood pressure (BP). In patients with mild-to-moderate hypertension irbesartan was as effective as enalapril, atenolol and amlodipine, and more effective than valsartan in terms of absolute reduction in BP and response rates. Irbesartan produced a greater reduction in diastolic BP at trough than once-daily losartan, but had a smaller effect than olmesartan; the reduction in systolic BP achieved with irbesartan was similar or greater than that with losartan and similar to that seen with olmesartan. The combination of irbesartan with hydrochlorothiazide produced additive effects on BP reduction. Irbesartan also induced regression of left ventricular mass in patients with hypertension and left ventricular hypertrophy. In two large studies (IRbesartan MicroAlbuminuria type 2 diabetes mellitus in hypertensive patients [IRMA 2] and the Irbesartan Diabetic Nephropathy Trial [IDNT]) irbesartan exerted a renoprotective effect in hypertensive patients with type 2 diabetes at both the early and later stages of diabetic nephropathy. The renoprotective effect was at least partly independent of the BP-lowering effect. In the IRMA 2 trial, the proportion of patients progressing to overt nephropathy was significantly lower for recipients of irbesartan 300mg once daily than placebo. In patients with overt nephropathy in the IDNT, irbesartan 300mg once daily provided significantly greater renoprotection than amlodipine 10mg once daily or placebo. The relative risk of doubling of serum creatinine was significantly lower with irbesartan than amlodipine or placebo. Irbesartan is well tolerated in hypertensive patients, including those with type 2 diabetes and incipient or overt nephropathy. The overall incidence of adverse events with irbesartan was similar to that with placebo. Irbesartan was associated with a lower incidence of cough than enalapril and was not associated with ankle oedema or with any clinically significant drug interactions. In conclusion, irbesartan is a well tolerated and effective antihypertensive agent. It also slows the progression of renal disease in hypertensive patients with type 2 diabetes at both the early and later stages of diabetic nephropathy. Thus, irbesartan is a valuable agent in the management of patients with these indications.

A randomized, double-blind, controlled, parallel-group comparison of perindopril and candesartan in hypertensive patients with type 2 diabetes mellitus

BACKGROUND

When choosing an antihypertensive drug for patients with hypertension and diabetes mellitus (DM), the metabolic side effects, possibility of improving some metabolic parameters, and need for adequate blood pressure control must all be considered.

OBJECTIVE

The goal of this study was to compare the impacts of perindopril and candesartan on blood pressure, glucose metabolism, serum lipid profile, and metabolic parameters in patients with mild hypertension and type 2 DM during therapy and after a 1-month washout period.

METHODS

Type 2 DM patients with mild hypertension and good glucose control who were not taking hypercholesterolemic drugs were enrolled. Perindopril 4 mg QD or candesartan 16 mg QD was administered for 12 months in this randomized, double-blind, controlled, parallel-group clinical trial. Fasting plasma glucose (FPG), fasting plasma insulin (FPI), glycosylated hemoglobin, homeostasis model assessment (HOMA) index, systolic blood pressure (SBP), diastolic blood pressure (DBP), total cholesterol (TC), low-density lipoprotein cholesterol (LDL-C), high-density lipoprotein cholesterol, triglycerides, lipoprotein(a) (Lp[a]), plasminogen activator inhibitor 1 (PAI-1), homocysteine, body mass index (BMI), and albumin excretion rate (AER) were assessed.

RESULTS

Ninety-six patients (49 women and 47 men; mean [SD] ages, 53 [10] years [perindopril] and 55 [9] years [candesartan]) were enrolled. Mean (SD) body weight, height, and BMI were 78.2 (9.4) kg, 1.69 (0.05) m, and 27.2 (2.0) kg/m(2) in the perindopril group and 77.5 (8.6) kg, 1.70 (0.06) m, and 26.8 (2.5) kg/m(2) in the candesartan group. A significant change occurred from baseline to month 12 during treatment with perindopril in SBP and DBP (both P < 0.01), FPG (P < 0.05), FPI (P < 0.05), TC (P < 0.05), LDL-C (P < 0.05), Lp(a) (P < 0.05), PAM (P < 0.05), and AER (P < 0.05). Significant changes from baseline to month 12 occurred with candesartan in SBP and DBP (both P < 0.01) and AER (P < 0.05). The HOMA index was significantly lower at month 12 in the perindopril group than in the candesartan group (P < 0.05). When we interrupted perindopril and candesartan therapy for a 1-month washout period, changes in SBP and DBP values were significant compared with month 12 in both groups (all P < 0.05). Changes in TC and LDL-C from month 12 to the end of washout were significant only in the perindopril group (both P < 0.05).

CONCLUSIONS

Perindopril and candesartan both effectively lowered blood pressure in this group of patients with mild hypertension and type 2 DM. Perindopril showed an improvement on some metabolic parameters compared with candesartan. However, the inclusion/exclusion criteria could limit the ability to extrapolate the results to a general population.

Valsartan-induced angioedema

OBJECTIVE

To report a case of dose-dependent angioedema secondary to the use of the angiotensin-receptor blocker (ARB) valsartan.

CASE SUMMARY

A 64-year-old Hispanic woman presented with swelling of the lips shortly after an increase in her valsartan dose for uncontrolled hypertension. Other potential causes were not identified. The angioedema subsequently resided after a dosage reduction and observation. Use of the Naranjo probability scale indicated a probable relationship between the angioedema and valsartan therapy in this patient.

DISCUSSION

Drug-induced angioedema is often associated with the use of angiotensin-converting enzyme (ACE) inhibitors and is probably secondary to their effects on bradykinin levels. ARBs are thought to produce few, if any, cases of angioedema if excess bradykinin levels are the root cause of angioedema secondary to ACE inhibitor use. Several potential ARB-induced cases of angioedema have been reported. The exact mechanism of angioedema induced by drugs in both of these classes is unknown. Animal data suggest that there may be a relationship between ARB use and increased tissue bradykinin levels secondary to stimulation of angiotensin II AT2 receptors.

CONCLUSIONS

This is the third reported case of valsartan-induced angioedema and the first thought to be dose dependent. Practitioners should be aware of this potential adverse effect of valsartan, although the underlying cause is still not known.

Angiotensin II receptor blockers and cardiovascular outcomes: what does the future hold?

The ability of angiotensin-converting enzyme (ACE) inhibitors and angiotensin II receptor blockers (ARBs) to lower blood pressure (BP) is well established. ACE inhibitors (ACE-Is) have also been shown to improve the prognosis of a broad range of patients at high cardiovascular risk, including those with heart failure, post-myocardial infarction (MI), and nephropathy. These benefits suggest that interrupting the renin-angiotensin-aldosterone system (RAAS) with ACE-Is has a widespread vasculoprotective effect, provided that BP is also adequately controlled. Evidence that RAAS blockade by ARBs also improves long-term clinical outcomes in patients with cardiovascular disease has started to accumulate, and will be tested further during the coming years as a number of large-scale, prospective trials are completed. These trials are investigating the long-term protective effects of ARBs on morbidity and mortality in patients with hypertension, heart failure, diabetes mellitus, acute MI, or established vascular disease. The results should establish the extent to which ARBs exhibit the vasculoprotective properties demonstrated by ACE-Is in patients at high cardiovascular risk. If ARBs are found to provide benefits that are similar to, or even greater than ACE-Is, it may have important implications for drug selection, given the excellent tolerability of ARBs. Some studies are also investigating whether more extensive RAAS blockade using a combination of an ARB and an ACE-I will offer even greater protection than either agent alone.

Angiotensin II receptor blockers in heart failure

Heart failure remains a significant cause of morbidity and mortality, despite major advances in therapy. Angiotensin II, the principal mediator of the renin-angiotensin system, exerts both short-term (e.g., hemodynamic, renal) and long-term (e.g., inflammation, cardiac remodeling) effects in the pathophysiology of cardiovascular disease. The effects of angiotensin II appear to be more completely inhibited by angiotensin II receptor blockers (ARBs), which act at the subtype 1 receptor level, than by angiotensin-converting enzyme (ACE) inhibitors because pathways other than that of ACE contribute to the generation of angiotensin II. Evidence demonstrates that ARBs, when added to conventional treatment for patients with heart failure, are associated with a reduction in morbidity and mortality as well as an improvement in quality of life. Clinical trials of ARB therapy indicate that these agents are generally well tolerated, both alone and in combination with other neurohormonal inhibitors. The current role of ARBs in heart failure is as an alternative for patients who cannot tolerate therapy with an ACE inhibitor. A number of ongoing clinical studies are likely to further define or expand the role of ARBs in the treatment of cardiovascular disease.

The pharmacokinetics and pharmacodynamics of angiotensin-receptor blockers in end-stage renal disease

Angiotensin-converting enzyme (ACE) inhibitors and more recently angiotensin-receptor blockers (ARBs) have become popular therapies in the end-stage renal disease (ESRD) patient. The ability of either of these drug classes to reduce blood pressure in the ESRD patient is well accepted; however, there is considerably less information available to guide the clinician in the safe and effective use of these drugs in the ESRD patient with congestive heart failure and/or coronary artery disease. Head-to-head studies in the ESRD patient are lacking for both drug classes. Several pharmacokinetic factors can influence the selection of these drugs, including dialysability and the propensity for systemic accumulation. ACE inhibitors (ACE-Is) and ARBs are recognised as having a range of nonpressor effects that are pertinent to patients with ESRD. Such effects include their ability to decrease both thirst drive and erythropoiesis. These drug classes, though, are distinguishable by the unique adverse effect profile for ACE-Is. As is the case in patients without renal failure, ESRD patients can experience cough and, less frequently, angioneurotic oedema with ACE-Is. In the ESRD population, so-called anaphylactoid dialyser reactions can occur in conjunction with ACE-I use. The use of a drug from within the ARB class carries both less risk and permits a compound with a preferred pharmacokinetic profile limited dialysability and minimal systemic accumulation to be administered. These attributes would favour the increased use of ARBs in this population.

Comparison of losartan with ACE inhibitors and dihydropyridine calcium channel antagonists: a pilot study of prescription-event monitoring in Japan

INTRODUCTION

Two pilot studies for prescription-event monitoring in Japan (J-PEM) were launched in 1997 and 1998. Here we present data regarding adverse events that were reported in the second pilot J-PEM study where losartan was compared with ACE inhibitors and dihydropyridine calcium channel antagonists.

STUDY DESIGN

We conducted a cohort study with a concurrent control. METHODS/PATIENT GROUP: Study subjects prescribed losartan, an ACE inhibitor or a calcium channel antagonist were identified from prescriptions in hospital or community pharmacies. Events and other information were collected from doctors and pharmacists by mailed questionnaires. Events were coded and analysed using the Medical Dictionary for Regulatory Activities (MedDRA) terminology. Crude event rates were calculated and compared between patients treated with losartan and those receiving control drugs. When the difference was statistically significant, the event was further examined in several ways, including follow-up studies and by comparison with the data of the UK PEM study on losartan.

RESULTS

Pharmacists were sent 4344 questionnaires and returned 3591 (83%), while doctors were sent 3517 questionnaires and returned 1380 (39%). In the doctors' data, the adverse event rate for losartan treatment was greater than that for ACE inhibitors and/or calcium channel antagonists for the following seven events: headache, palpitations, anaemia, insomnia, feeling abnormal, increased blood pressure and asthma. Most of these are known adverse drug reactions (ADRs) of losartan except for two events: increased blood pressure and asthma. In pharmacists' data, the event rate for losartan was significantly greater than that for control drugs for the following ten events: hot flushes, abnormal hepatic function, oedema, peripheral swelling, decreased blood pressure, increased blood pressure, rhinitis, contact dermatitis, dry skin and heat rash. The first five events were known ADRs of losartan but the other five were not. When the two sets of data were combined, the rate of an additional event, increased blood creatinine phosphokinase, which is a known ADR of losartan, was significantly greater than that for the control drugs. The six events that were not documented as ADRs for losartan were not judged to be ADRs based on the results of follow-up studies and comparison with the UK PEM study on losartan. The crude rate of cough with losartan treatment was similar to that with calcium channel antagonists, but was significantly less than that with ACE inhibitors.

CONCLUSION

No novel safety problems were found in this observational cohort study on losartan. The rates of some known ADRs differed significantly between patients treated with losartan and those in the control groups.

Role of valsartan and other angiotensin receptor blocking agents in the management of cardiovascular disease

Blockade of the renin-angiotensin system by angiotensin converting enzyme (ACE) inhibitors reduces mortality and morbidity in patients post-myocardial infarction as well as in chronic heart failure and hypertension. ACE inhibitors also have a well-established place in the treatment of diabetic nephropathy. Angiotensin receptor blockers (ARBs) have been developed to produce a more complete blockade of the actions of angiotensin II as compared to other drug classes, as well as an improved side effect profile. This article provides an overview of the place of ARBs in general and of the ARB valsartan in particular, and draws comparisons to ACE inhibitors in the treatment of cardiovascular diseases.

Optimizing the diabetic formulary: beyond aspirin and insulin

Type 2 diabetes mellitus (DM) afflicts nearly 16 million persons in the U.S. Forty million people have impaired glucose tolerance and thus have a 10% annualized risk of developing type 2 DM. These prevalence rates are estimated to double within the next two decades. At-risk groups appear to be the elderly and minorities including African, Hispanic and Native Americans. While the epidemiologic underpinnings for this increase are not fully realized, there has been a parallel increase in societal obesity, sedentary lifestyle and a marked increase in type 2 DM among children. Although there have recently been noteworthy advances in the field of cardiovascular medicine, cardiovascular case fatalities remain the leading cause of death among diabetic patients. According to national health statistics, there continues to be a downward trend in cardiovascular mortality and morbidity. This observation has not been consistently noted among patients with DM and has led many to re-evaluate current treatment goals and pharmacologic regimens for the at-risk patients with type 2 DM. This shifting treatment paradigm for diabetic patients has led to a ratcheting down of targeted risk factor goals including low-density lipoprotein cholesterol, systolic and diastolic blood pressure, and serum glucose levels with a requisite increase in the number of pharmacologic agents being administered. This review focuses on the current adjunctive pharmacologic treatment regimen that is well suited for patients with type 2 DM.

A population-based European cohort study of persistence in newly diagnosed hypertensive patients

This study assessed the percentage of patients after 1 year who persisted on initially prescribed antihypertensive therapy. Medical records of 2416 patients with newly diagnosed hypertension who were prescribed initial antihypertensive monotherapy by general practitioners in Germany, France, and the United Kingdom were evaluated. Comparisons were made among the angiotensin II receptor antagonist (AIIRA) irbesartan, all other antihypertensive classes (including AIIRAs other than irbesartan), and the AIIRA losartan. Patients initiated on the AIIRA irbesartan scored highest with a persistence rate of 60.8%, followed by patients who received all other AIIRA agents with a persistence rate of 51.3%. Angiotensin-converting enzyme inhibitors, calcium channel blockers, beta-blockers, and losartan were associated with comparable persistence rates, between 42.0% and 49.7%. Patients who received diuretics scored lowest with a persistence rate of 34.4%. Persistence has emerged as an essential factor for blood pressure control. Prescribing an antihypertensive agent that provides a favourable efficacy and tolerability profile may provide greater persistence with therapy and hence a higher level of blood pressure control.

Treating hypertension in patients with diabetes

The coexistence of hypertension and diabetes synergistically increases the risk of cardiovascular and renal diseases. Although aggressive blood pressure reduction can decrease the rate of cardiovascular events in general, blockade of the renin-aldosterone-angiotensin system is a particularly effective target for antihypertensive treatment that may provide additional benefits for patients with diabetes. This article details evidence for blood pressure targets and antihypertensive drug choice in hypertensive patients with diabetes.

Clinical differences among angiotensin II receptor antagonists

The six major classes of antihypertensive agents prescribed worldwide are similar in efficacy but dissimilar in tolerability. Recently, the World Health Organization-International Society of Hypertension (WHO-ISH) concluded that agents from all six classes are suitable for the initiation and maintenance of antihypertensive therapy, including the newest class of agents, the angiotensin II receptor antagonists (AIIRAs). The ideal antihypertensive agent should be effective and well tolerated, as well as synergistic in blood pressure-lowering effects when combined with other agents. As monotherapy, AIIRAs have demonstrated efficacy similar to other classes of antihypertensive agents in numerous clinical trials. Several AIIRAs have also demonstrated enhanced efficacy when combined with a low dose of the diuretic hydrochlorothiazide (HCTZ). A well-known feature of this new class of agents is placebo-level tolerability; however, less is known about intra-class differences. Losartan, the first approved AIIRA, has become an important benchmark for within-class comparisons with respect to antihypertensive efficacy. Head-to-head comparisons between losartan and newer AIIRAs have been conducted; their cumulative results indicate that the antihypertensive effect and antagonistic activity of losartan may be the weakest among AIIRAs. In a recent clinical trial, we demonstrated that irbesartan produces statistically superior blood pressure reduction when compared to valsartan. This may have clinical implications for agent selection among the AIIRAs.