An economic evaluation of antihypertensive therapies based on clinical trials

OBJECTIVE: Hypertension is a major issue in public health, and the financial costs associated with hypertension continue to increase. Cost-effectiveness studies focusing on antihypertensive drug combinations, however, have been scarce. The cost-effectiveness ratios of the traditional treatment (hydrochlorothiazide and atenolol) and the current treatment (losartan and amlodipine) were evaluated in patients with grade 1 or 2 hypertension (HT1-2). For patients with grade 3 hypertension (HT3), a third drug was added to the treatment combinations: enalapril was added to the traditional treatment, and hydrochlorothiazide was added to the current treatment. METHODS: Hypertension treatment costs were estimated on the basis of the purchase prices of the antihypertensive medications, and effectiveness was measured as the reduction in systolic blood pressure and diastolic blood pressure (in mm Hg) at the end of a 12-month study period. RESULTS: When the purchase price of the brand-name medication was used to calculate the cost, the traditional treatment presented a lower cost-effectiveness ratio [US$/mm Hg] than the current treatment in the HT1-2 group. In the HT3 group, however, there was no difference in cost-effectiveness ratio between the traditional treatment and the current treatment. The cost-effectiveness ratio differences between the treatment regimens maintained the same pattern when the purchase price of the lower-cost medication was used. CONCLUSIONS: We conclude that the traditional treatment is more cost-effective (US$/mm Hg) than the current treatment in the HT1-2 group. There was no difference in cost-effectiveness between the traditional treatment and the current treatment for the HT3 group

An international prospective cohort study evaluating major vascular complications among patients undergoing noncardiac surgery : the VISION Pilot Study

Objectives: Among patients undergoing noncardiac surgery, our objectives were to: (1) determine the feasibility of undertaking a large international cohort study; (2) estimate the current incidence of major perioperative vascular events; (3) compare the observed event rates to the expected event rates according to the Revised Cardiac Risk Index (RCRI); and (4) provide an estimate of the proportion of myocardial infarctions without ischemic symptoms that may go undetected without perioperative troponin monitoring. Design: An international prospective cohort pilot study. Participants: Patients undergoing noncardiac surgery who were >45 years of age, receiving a general or regional anesthetic, and requiring hospital admission. Measurements: Patients had a Roche fourth-generation Elecsys troponin T measurement collected 6 to 12 hours postoperatively and on the first, second, and third days after surgery. Our primary outcome was major vascular events (a composite of vascular death [i.e., death from vascular causes], nonfatal myocardial infarction, nonfatal cardiac arrest, and nonfatal stroke) at 30 days after surgery. Our definition for perioperative myocardial infarction included: (1) an elevated troponin T measurement with at least one of the following defining features: ischemic symptoms, development of pathologic Q waves, ischemic electrocardiogram changes, coronary artery intervention, or cardiac imaging evidence of myocardial infarction; or (2) autopsy findings of acute or healing myocardial infarction. Results: We recruited 432 patients across 5 hospitals in Canada, China, Italy, Colombia, and Brazil. During the first 30 days after surgery, 6.3% (99% confidence interval 3.9–10.0) of the patients suffered a major vascular event (10 vascular deaths, 16 nonfatal myocardial infarctions, and 1 nonfatal stroke). The observed event rate was increased 6-fold compared with the event rate expected from the RCRI. Of the 18 patients who suffered a myocardial infarction, 12 (66.7%) had no ischemic symptoms to suggest myocardial infarction. Conclusions: This study suggests that major perioperative vascular events are common, that the RCRI underestimates risk, and that monitoring troponins after surgery can assist physicians to avoid missing myocardial infarction. These results underscore the need for a large international prospective cohort study

Inibidores de enzima conversora de angiotensina para a prevenção de eventos cardiovasculares em pacientes de alto risco : revisão sistemática e metanálise de ensaios clínicos randomizados

Justificativa: A ativação do sistema-rerina-aldosterona (SRAA) constitui um importante componente da fisiopatologia de doenças ateroscleróticas, as quais representam a principal causa de mortalidade e incapacidade no Brasil e no Mundo. Nos últimos anos, foi publicada uma série de evidências sugerindo que o bloqueio do SRRA com inibidores da enzima conversora de angiotensina (ECA) possui efeito benéfico em prevenir desfechos cardiovasculares em pacientes com insuficiência cardíaca e disfunção ventricular esquerda. Em pacientes de alto risco cardiovascular com função ventricular esquerda preservada, ensaios clínicos randomizados individuais obtiveram resultados inconsistentes. Objetivos: Foi conduzida uma revisão sistemática e metanálise com o objetivo de avaliar criticamente o estudos disponíveis, de obter uma estimativa de efeito mais típica e precisa e de determinar se a totalidade das evidências pode ser considerada conclusiva e definitva. Fontes de Dados: MEDLINE, EMBASE, the Cochrane controlled trials register (CENTRAL), anais de congressos, registros de ensaios clínicos, referências dos estudos incluídos o com especialistas Seleção dos Estudos: Foram incluídos ensaios clínicos randomizados que avaliaram o tratamento de inibidores da ECA em pacientes sem insuficiência cardíaca ou disfunção lar, mas de alto risco para eventos cardiovasculares (a exemplo daqueles com manifestações de aterosclerose e diabéticos com idade maior do que 50 anos e fatores de risco ais para doenças ateroscleróticas). Extração dos Dados: Qualidade metodológica dos estudos, mortalidade total , eventos cardiovasculares maiores (infarto do miocárdio não-fatal, mortalidade cardiovascular, vascular cerebral não-fatal, insuficiência cardíaca necessitando de hospitalização) e efeitos adversos. Resultados: Dezenove ensaios clínicos completados (46.022 pacientes) preencheram de inclusão. Cinco destes estudos incluíram apenas pacientes diabéticos de alto risco pacientes( 10.389 pacientes). Todos os estudos reportaram análise por intenção de tratar, a maioria destes utilizou cegamente de pacientes, investigadores e avaliadores de desfechos (89,5%), Mas apenas 63, I% reportou como o sigilo da lista de randomização foi mantido. Inibidores da ECA demonstraram efeitos benéficos de magnitude moderada em mortalidade total (risco 0,92, intervalo de confiança de 95% 0,87 a 0,98), mortalidade cardiovascular (risco 0,88, intervalo de confiança de 95% 0,8I a 0,96), infarto do miocárdio não-fatal (risco 0,83, intervalo de confiança de 95% 0,77 a 0,89), acidente vascular cerebral (risco 0,85, intervalo de confiança 95% O,77 a 0,94) e insuficiência cardíaca (risco relativo intervalo de confiança de 95% 0,65 a 0,86). No subgrupo de pacientes com diabetes, os inibidores da ECA demonstraram efeitos benéficos em um desfecho combinado de mortalidade cardiovascular, infarto do miocárdio não-fatal e acidente vascular cerebral (risco 0,79, intervalo de confiança de 95% 0,70 a 0,90), bem como em desfechos individuais mortalidade cardiovascular (risco relativo 0,82, intervalo de confiança de 95% 0,71 a infarto do miocárdio não-fatal (risco relativo 0,80, intervalo de confiança de 95% 0,69 a 0.93). Os efeitos na pressão arterial foram de pequena magnitude (redução de 2,89 mmHg na pressão sistólica e de I ,50 mmHg na pressão diastólica). Conclusão: As evidências disponíveis confirmam que inibidores da ECA reduzem cardiovasculares maiores em pacientes de alto risco cardiovascular sem insuficiência a. A totalidade das evidências parece conclusiva e definitiva para infarto do miocárdio, o para mortalidade total.Background: Currently, activation of the renin-angiotensin-aldosterone system has also been recognized as an important component of the pathogenesis of atherosclerotic diseases, the leading causes of mortality and disability worldwide. Over the last years, evidence has emerged indicating that blockade of the RAAS with angiotensin converting enzyme (ACE) inhibitors are associated with reduced major cardiovascular events in patients with heart failure and left ventricular systolic dysfunction. In high risk patients with preserved systolic function, individual randomized clinical trials have yielded inconsistent results. Objectives: We undertook a systematic review and meta-analysis to critically appraise the le trials, to obtain a typical and unbiased estimate of treatment effect and to determine if the totality of evidence is reliable and conclusive. Data sources MEDLINE, EMBASE, the Cochrane controlled trials register (CENTRAL), conference proceedings, trial registers, references lists of all available primary studies and contact with experts. Selection: We included randomized controlled trials (RCTs) that evaluated ACE inhibitor therapy in patients at high risk for cardiovascular events (patients without heart or systolic dysfunction, but with manifestations of atherosclerosis and diabetics with risk for atherosclerotic disease). Data extraction: Methodological quality of trials, ali-cause mortality, cardiovascular outcomes (myocardial infarction, cardiovascular mortality, stroke, heart failure, coronary revascularization) and side effects. Results: Nineteen completed trials (46.022 patients) met eligibility criteria. Five of these trials included only high risk diabetic patients (10.389 patientes). All trials used intention-to­ treat alysis, most RCTs were blinded (89.5%), but only 63.1% reported that the allocation list was concealed. ACE inhibitors demonstrated moderate beneficiai effects on total mortality (relative risk 0.92, 95% confidence interval 0.87 to 0.98), cardiovascular mortality (relative risk 08, 95% confidence interval 0.81 to 0.96), myocardial infarction (relative risk 0.83, confidence interval 0.77 to 0.89), stroke (relative risk 0.85, 95% confidence interval 0.77 to 0.94) and heart failure requiring hospitalization (relative risk 0.75, 95% confidence interval 0.86). In the subgroup of diabetic patients, ACE lnhibitors demonstrated moderate beneficiai effects on a combined endpoint of cardiovascular mortality, myocardial infarction infarction and stroke (relative risk 0.79, 95% CI 0.70 to 0.90), and on individual outcomes such as cardiovascular mortality (relative risk 0.82, 95% CI 0.71 to 0.96), and myocardial infarction e (relative risk 0.80, 95% CI 0.69 to 0.93). The effects on blood pressure reduction were of small magnitude (2.89 mmHg reduction on systolic and 1.5 reduction on diastolic pressure) whem compared to placebo or no treatment. Conclusion: The available evidence confirms that ACE Inhibitors reduce major cardiovascular events and mortality in high risk patients without known heart failure. The of the evidence seems to be conclusive and reliable for myocardial infarction but not a use mortality

Inibidores de enzima conversora de angiotensina para a prevenção de eventos cardiovasculares em pacientes de alto risco : revisão sistemática e metanálise de ensaios clínicos randomizados

Justificativa: A ativação do sistema-rerina-aldosterona (SRAA) constitui um importante componente da fisiopatologia de doenças ateroscleróticas, as quais representam a principal causa de mortalidade e incapacidade no Brasil e no Mundo. Nos últimos anos, foi publicada uma série de evidências sugerindo que o bloqueio do SRRA com inibidores da enzima conversora de angiotensina (ECA) possui efeito benéfico em prevenir desfechos cardiovasculares em pacientes com insuficiência cardíaca e disfunção ventricular esquerda. Em pacientes de alto risco cardiovascular com função ventricular esquerda preservada, ensaios clínicos randomizados individuais obtiveram resultados inconsistentes. Objetivos: Foi conduzida uma revisão sistemática e metanálise com o objetivo de avaliar criticamente o estudos disponíveis, de obter uma estimativa de efeito mais típica e precisa e de determinar se a totalidade das evidências pode ser considerada conclusiva e definitva. Fontes de Dados: MEDLINE, EMBASE, the Cochrane controlled trials register (CENTRAL), anais de congressos, registros de ensaios clínicos, referências dos estudos incluídos o com especialistas Seleção dos Estudos: Foram incluídos ensaios clínicos randomizados que avaliaram o tratamento de inibidores da ECA em pacientes sem insuficiência cardíaca ou disfunção lar, mas de alto risco para eventos cardiovasculares (a exemplo daqueles com manifestações de aterosclerose e diabéticos com idade maior do que 50 anos e fatores de risco ais para doenças ateroscleróticas). Extração dos Dados: Qualidade metodológica dos estudos, mortalidade total , eventos cardiovasculares maiores (infarto do miocárdio não-fatal, mortalidade cardiovascular, vascular cerebral não-fatal, insuficiência cardíaca necessitando de hospitalização) e efeitos adversos. Resultados: Dezenove ensaios clínicos completados (46.022 pacientes) preencheram de inclusão. Cinco destes estudos incluíram apenas pacientes diabéticos de alto risco pacientes( 10.389 pacientes). Todos os estudos reportaram análise por intenção de tratar, a maioria destes utilizou cegamente de pacientes, investigadores e avaliadores de desfechos (89,5%), Mas apenas 63, I% reportou como o sigilo da lista de randomização foi mantido. Inibidores da ECA demonstraram efeitos benéficos de magnitude moderada em mortalidade total (risco 0,92, intervalo de confiança de 95% 0,87 a 0,98), mortalidade cardiovascular (risco 0,88, intervalo de confiança de 95% 0,8I a 0,96), infarto do miocárdio não-fatal (risco 0,83, intervalo de confiança de 95% 0,77 a 0,89), acidente vascular cerebral (risco 0,85, intervalo de confiança 95% O,77 a 0,94) e insuficiência cardíaca (risco relativo intervalo de confiança de 95% 0,65 a 0,86). No subgrupo de pacientes com diabetes, os inibidores da ECA demonstraram efeitos benéficos em um desfecho combinado de mortalidade cardiovascular, infarto do miocárdio não-fatal e acidente vascular cerebral (risco 0,79, intervalo de confiança de 95% 0,70 a 0,90), bem como em desfechos individuais mortalidade cardiovascular (risco relativo 0,82, intervalo de confiança de 95% 0,71 a infarto do miocárdio não-fatal (risco relativo 0,80, intervalo de confiança de 95% 0,69 a 0.93). Os efeitos na pressão arterial foram de pequena magnitude (redução de 2,89 mmHg na pressão sistólica e de I ,50 mmHg na pressão diastólica). Conclusão: As evidências disponíveis confirmam que inibidores da ECA reduzem cardiovasculares maiores em pacientes de alto risco cardiovascular sem insuficiência a. A totalidade das evidências parece conclusiva e definitiva para infarto do miocárdio, o para mortalidade total.Background: Currently, activation of the renin-angiotensin-aldosterone system has also been recognized as an important component of the pathogenesis of atherosclerotic diseases, the leading causes of mortality and disability worldwide. Over the last years, evidence has emerged indicating that blockade of the RAAS with angiotensin converting enzyme (ACE) inhibitors are associated with reduced major cardiovascular events in patients with heart failure and left ventricular systolic dysfunction. In high risk patients with preserved systolic function, individual randomized clinical trials have yielded inconsistent results. Objectives: We undertook a systematic review and meta-analysis to critically appraise the le trials, to obtain a typical and unbiased estimate of treatment effect and to determine if the totality of evidence is reliable and conclusive. Data sources MEDLINE, EMBASE, the Cochrane controlled trials register (CENTRAL), conference proceedings, trial registers, references lists of all available primary studies and contact with experts. Selection: We included randomized controlled trials (RCTs) that evaluated ACE inhibitor therapy in patients at high risk for cardiovascular events (patients without heart or systolic dysfunction, but with manifestations of atherosclerosis and diabetics with risk for atherosclerotic disease). Data extraction: Methodological quality of trials, ali-cause mortality, cardiovascular outcomes (myocardial infarction, cardiovascular mortality, stroke, heart failure, coronary revascularization) and side effects. Results: Nineteen completed trials (46.022 patients) met eligibility criteria. Five of these trials included only high risk diabetic patients (10.389 patientes). All trials used intention-to­ treat alysis, most RCTs were blinded (89.5%), but only 63.1% reported that the allocation list was concealed. ACE inhibitors demonstrated moderate beneficiai effects on total mortality (relative risk 0.92, 95% confidence interval 0.87 to 0.98), cardiovascular mortality (relative risk 08, 95% confidence interval 0.81 to 0.96), myocardial infarction (relative risk 0.83, confidence interval 0.77 to 0.89), stroke (relative risk 0.85, 95% confidence interval 0.77 to 0.94) and heart failure requiring hospitalization (relative risk 0.75, 95% confidence interval 0.86). In the subgroup of diabetic patients, ACE lnhibitors demonstrated moderate beneficiai effects on a combined endpoint of cardiovascular mortality, myocardial infarction infarction and stroke (relative risk 0.79, 95% CI 0.70 to 0.90), and on individual outcomes such as cardiovascular mortality (relative risk 0.82, 95% CI 0.71 to 0.96), and myocardial infarction e (relative risk 0.80, 95% CI 0.69 to 0.93). The effects on blood pressure reduction were of small magnitude (2.89 mmHg reduction on systolic and 1.5 reduction on diastolic pressure) whem compared to placebo or no treatment. Conclusion: The available evidence confirms that ACE Inhibitors reduce major cardiovascular events and mortality in high risk patients without known heart failure. The of the evidence seems to be conclusive and reliable for myocardial infarction but not a use mortality