Reappraisal of role of angiotensin receptor blockers in cardiovascular protection

Prevalence and factors associated with adherence to anti-hypertensives among adults with hypertension in a developed Asian community: A cross-sectional study

Introduction:

Poor adherence to anti-hypertensive medications (AHM) results in hypertension treatment failure. Understanding and addressing the factors associated with adherence to AHM may potentially improve health outcomes. This study aimed to assess the prevalence and factors associated with patients’ adherence to AHM in a developed Asian community.

Methods:

An assistant-administered questionnaire survey was conducted on multi-ethnic Asian adults aged 31–80 years with essential hypertension based on their electronic health records (EHR) at a public primary-care clinic. Data on their demographic characteristics, clinical measurements of blood pressure and body mass index, co-morbidities and prescriptions from the EHR, along with the Medication Adherence Report Scale-5 scores were collated, audited and analysed. A MARS-5 score of <25 indicated poor adherence. Logistic regression was used to identify factors associated with adherence to AHM.

Results:

Data of 395 patients were analysed. Of these, 179 (45.3%) had poor adherence to at least one AHM. Bivariate analysis showed that poor adherence was significantly associated with lower mean age (59 years old vs. 63 years old), higher mean clinic diastolic blood pressure (76 mmHg vs. 73 mmHg) and higher mean weight (70.4 kg vs. 67.4 kg). Logistic regression showed that patients with no co-morbidities (such as diabetes mellitus, dyslipidaemia, stroke and ischaemic heart disease) had better medication adherence (MA; odds ratio=1.98; 95% confidence interval 1.14–3.45; p=0.02). There was no significant MA difference between the classes, dose frequency and number of AHM.

Conclusion:

Almost half of the patients had poor adherence to at least one AHM. Co-morbidity significantly influenced their MA. Attention should be directed to patients with co-morbidities to assess their AHM adherence.

Meta-analysis of the effects of preoperative renin-angiotensin system inhibitor therapy on major adverse cardiac events in patients undergoing cardiac surgery

The purpose of this meta-analysis was to assess the role of preoperative renin-angiotensin system inhibitor (RASI) therapy on major adverse cardiac events (MACE) in patients undergoing cardiac surgery. The Medline, Cochrane Library and Embase databases were searched for clinical studies published up to May 2014. Studies that evaluated the effects of preoperative RASI therapy in cardiac surgery were included. Odds ratio (OR) estimates were generated under a random-effects model. After a literature search in the major databases, 18 studies were identified [three randomized prospective clinical trials (RCTs) and 15 observational trials] that reported outcomes of 54 528 cardiac surgery patients with (n = 22 661; 42%) or without (n = 31 867; 58%) preoperative RASI therapy. Pool analysis indicated that preoperative RASI therapy was not associated with a significant reduction of early all-cause mortality [OR: 1.01; 95% confidence interval (CI) 0.88-1.15, P = 0.93; I(2) = 25%], myocardial infarction (OR: 1.04; 95% CI 0.91-1.19, P = 0.60; I(2) = 16%), or stroke (OR: 0.93; 95% CI 0.75-1.14, P = 0.46; I(2) = 38%). Meta-regression analysis confirmed that there was a strong negative correlation between the percentage of diabetics and early all-cause mortality (P = 0.03). Furthermore, preoperative RASI therapy significantly reduced mortality in studies containing a high proportion of diabetic patients (OR: 0.84; 95% CI 0.71-0.99, P = 0.04; I(2) = 0%). In conclusion, our meta-analysis indicated that although preoperative RASI therapy was not associated with a lower risk of MACE in cardiac surgery patients, it might provide benefits for diabetic patients.

Comparative effectiveness of renin-angiotensin system blockers and other antihypertensive drugs in patients with diabetes: systematic review and bayesian network meta-analysis

OBJECTIVE

To assess the effects of different classes of antihypertensive treatments, including monotherapy and combination therapy, on survival and major renal outcomes in patients with diabetes.

DESIGN

Systematic review and bayesian network meta-analysis of randomised clinical trials.

DATA SOURCES

Electronic literature search of PubMed, Medline, Scopus, and the Cochrane Library for studies published up to December 2011.

STUDY SELECTION

Randomised clinical trials of antihypertensive therapy (angiotensin converting enzyme (ACE) inhibitors, angiotensin receptor blockers (ARBs), α blockers, β blockers, calcium channel blockers, diuretics, and their combinations) in patients with diabetes with a follow-up of at least 12 months, reporting all cause mortality, requirement for dialysis, or doubling of serum creatinine levels.

DATA EXTRACTION

Bayesian network meta-analysis combined direct and indirect evidence to estimate the relative effects between treatments as well as the probabilities of ranking for treatments based on their protective effects.

RESULTS

63 trials with 36,917 participants were identified, including 2400 deaths, 766 patients who required dialysis, and 1099 patients whose serum creatinine level had doubled. Compared with placebo, only ACE inhibitors significantly reduced the doubling of serum creatinine levels (odds ratio 0.58, 95% credible interval 0.32 to 0.90), and only β blockers showed a significant difference in mortality (odds ratio 7.13, 95% credible interval 1.37 to 41.39). Comparisons among all treatments showed no statistical significance in the outcome of dialysis. Although the beneficial effects of ACE inhibitors compared with ARBs did not reach statistical significance, ACE inhibitors consistently showed higher probabilities of being in the superior ranking positions among all three outcomes. Although the protective effect of an ACE inhibitor plus calcium channel blocker compared with placebo was not statistically significant, the treatment ranking identified this combination therapy to have the greatest probability (73.9%) for being the best treatment on reducing mortality, followed by ACE inhibitor plus diuretic (12.5%), ACE inhibitors (2.0%), calcium channel blockers (1.2%), and ARBs (0.4%).

CONCLUSIONS

Our analyses show the renoprotective effects and superiority of using ACE inhibitors in patients with diabetes, and available evidence is not able to show a better effect for ARBs compared with ACE inhibitors. Considering the cost of drugs, our findings support the use of ACE inhibitors as the first line antihypertensive agent in patients with diabetes. Calcium channel blockers might be the preferred treatment in combination with ACE inhibitors if adequate blood pressure control cannot be achieved by ACE inhibitors alone.

Patterns of use of perioperative angiotensin-converting enzyme inhibitors in coronary artery bypass graft surgery with cardiopulmonary bypass: effects on in-hospital morbidity and mortality

BACKGROUND

Despite proven benefit in ambulatory patients with ischemic heart disease, the pattern of use of angiotensin-converting enzyme inhibitors (ACEIs) in coronary artery bypass graft surgery has been erratic and controversial.

METHODS AND RESULTS

This is a prospective observational study of 4224 patients undergoing coronary artery bypass graft surgery. The cohort included 1838 patients receiving ACEI therapy before surgery and 2386 (56.5%) without ACEI exposure. Postoperatively, the pattern of ACEI use yielded 4 groups: continuation, 915 (21.7%); withdrawal, 923 (21.8%); addition, 343 (8.1%); and no ACEI, 2043 (48.4%). Continuous treatment with ACEI versus no ACEI was associated with substantive reductions of risk of nonfatal events (adjusted odds ratio for the composite outcome, 0.69; 95% confidence interval, 0.52-0.91; P=0.009) and a cardiovascular event (odds ratio, 0.64; 95% confidence interval, 0.46-0.88; P=0.006). Addition of ACEI de novo postoperatively compared with no ACEI therapy was also associated with a significant reduction of risk of composite outcome (odds ratio, 0.56; 95% confidence interval, 0.38-0.84; P=0.004) and a cardiovascular event (odds ratio, 0.63; 95% confidence interval, 0.40-0.97; P=0.04). On the other hand, continuous treatment of ACEI versus withdrawal of ACEI was associated with decreased risk of the composite outcome (odds ratio, 0.50; 95% confidence interval, 0.38-0.66; P<0.001), as well as a decrease in cardiac and renal events (P<0.001 and P=0.005, respectively). No differences in in-hospital mortality and cerebral events were noted.

CONCLUSIONS

Our study suggests that withdrawal of ACEI treatment after coronary artery bypass graft surgery is associated with nonfatal in-hospital ischemic events. Furthermore, continuation of ACEI or de novo ACEI therapy early after cardiac surgery is associated with improved in-hospital outcomes.