Updated meta-analytical approach to the efficacy of antihypertensive drugs in reducing blood pressure

Cardiovascular health and proximity to urban oil drilling in Los Angeles, California

BACKGROUND

Although ~18 million people live within a mile from active oil and gas development (OGD) sites in the United States, epidemiological research on how OGD affects the health of nearby urban residents is sparse. Thousands of OGD sites are spread across Los Angeles (LA) County, California, home to the largest urban oil production in the country. Air pollution and noise from OGD may contribute to cardiovascular morbidity.

OBJECTIVE

We examined the association between proximity to OGD and blood pressure in a diverse cohort of residents in LA.

METHODS

We recruited residents in South LA who lived <1 km from an OGD site. We collected three blood pressure measurements for each participant and used the second and third measurements to calculate averages for systolic blood pressure (SBP) and diastolic blood pressure (DBP) separately. We conducted multivariable linear regression to examine the relationship between distance to OGD sites and continuous SBP and DBP, adjusting for BMI, smoking status, distance to freeway, sex, age, and use of antihypertension medications, with a random effect for household. We examined effect measure modification by BMI category and smoking category.

RESULTS

Among the 623 adult participants, we found that for every 100 meter increase in distance from the OGD site, DBP was reduced by an average of 0.73 mmHg (95% CI: -1.26, -0.21) in this population. We observed stronger effects of proximity to OGD site on DBP among never smokers and among participants with a healthy BMI. The associations observed between proximity to OGD site and SBP were weaker but followed the same patterns as those for DBP.

IMPACT

Our study suggests that living near urban oil drilling sites is significantly associated with greater diastolic blood pressure in urban Los Angeles communities. This research improves understanding of impacts from living nearby drilling operations on the health and welfare of this community, which is critical to inform public health relevant strategies.

Benefit of treatment based on indapamide mostly combined with perindopril on mortality and cardiovascular outcomes: a pooled analysis of four trials

OBJECTIVE

The aim of this study was to assess the reduction in all-cause death and cardiovascular outcomes associated with the administration of the thiazide-like diuretic indapamide monotherapy or in combination with perindopril as a blood pressure lowering drug in randomized controlled trials (RCTs).

METHOD

Aggregate data from four published RCTs conducted versus matching placebo were pooled: PATS, a 2-year study (indapamide), and PROGRESS, a 4-year study (indapamide and perindopril), both in patients with a history of stroke or transient ischemic attack; ADVANCE, a 4-year study in patients with type 2 diabetes and cardiovascular risk factor (single-pill combination perindopril/indapamide) and HYVET, a 2-year study in very elderly hypertensive individuals (indapamide and an option of perindopril). The pooled effect (fixed and random) estimate (hazard ratio) was reported with corresponding 95% confidence intervals and P values. Treatment discontinuations were also analysed to assess the net benefit of the treatment.

RESULTS

The population involved 24 194 patients (active: 12 113, placebo: 12 081). The fixed-effects meta-analysis of the three mortality endpoints found low statistical heterogeneity ( I2  = 0). Statistically significant risk reductions in the indapamide with or without perindopril-treated patients as compared to placebo were observed for all-cause death (-15%), cardiovascular death (-21%), fatal stroke (-36%) and all strokes (-27%). Other cardiovascular outcomes were improved (risk reduction, 22 to 36%). As expected, discontinuation rates for safety (two studies) were higher in the active group (6.4 vs. 3.9%), while they were similar when discontinuation for any reason is concerned (18.4 vs. 18.0%).

CONCLUSION

Across medium to high cardiovascular risk population, long-term indapamide, mostly combined with perindopril-based treatment, provided evidence of benefit on mortality and morbidity.

Fossil-fuel and combustion-related air pollution and hypertension in the Sister Study

Hypertension is a leading risk factor for disease burden, with more than 200 million disability-adjusted life-years attributed to high blood pressure in 2015. While outdoor air pollution is associated with cardiovascular disease, the joint effect of exposure to air pollution from combustion products on hypertension has rarely been studied. We conducted a cross-sectional analysis to explore the association between combustion-related air pollution and hypertension. Census-tract levels of ambient concentrations of nine fossil-fuel and combustion-related air toxics (biphenyl, naphthalene, polycyclic organic matter, diesel emissions, 1,3-butadiene, acetaldehyde, benzene, acrolein, and formaldehyde) from the 2005 National Air Toxics Assessment database and NO2 from 2005 monitoring data were linked to baseline residential addresses of 47,467 women in the Sister Study cohort. Hypertension at enrollment (2003-2009) was defined as high systolic (≥140 mm Hg) or diastolic (≥90 mm Hg) blood pressure or taking antihypertensive medication. We used log-binomial regression and quantile-based g-computation to estimate the individual and joint effects of fossil-fuel and combustion-related air pollution on hypertension. Comparing the highest to lowest quartiles, diesel emissions (prevalence ratio (PR) = 1.05, 95% confidence interval (CI) = 1.01,1.08), 1,3-butadiene (PR = 1.04, 95%CI = 1.00,1.07), acetaldehyde (PR = 1.08, 95%CI = 1.04,1.12), benzene (PR = 1.05, 95%CI = 1.02,1.08), formaldehyde (PR = 1.08, 95%CI = 1.04,1.11), and NO2 (PR = 1.08, 95%CI = 1.05,1.12) were individually associated with higher prevalence of hypertension. The PR for the joint effect of increasing all ambient air toxics and NO2 by one quartile was 1.02 (95%CI = 1.01,1.04). Associations varied by race/ethnicity, with stronger associations observed among women reporting races/ethnicities (Hispanic/Latina, non-Hispanic Black and other) other than non-Hispanic White. In conclusion, we found that air pollution from fossil fuel and combustion may be a risk factor for hypertension.

Roles of sleep-related cardiovascular autonomic functions in voluntary-exercise-induced alleviation of hypertension in spontaneously hypertensive rats

Autonomic dysfunction and sleep problems are closely associated with hypertension and predict cardiovascular morbidity and mortality. Animal studies and clinical observations have identified exercise as an important factor in preventing and treating hypertension. However, the roles of autonomic function and sleep in the antihypertensive mechanisms of exercise are still not fully understood. This study aimed to clarify the physiological mechanisms associated with autonomic function and sleep through wheel exercise. Male spontaneously hypertensive rats (SHRs) were grouped into a wheel-exercised group and a sedentary group (controls). Electroencephalogram, electromyogram, electrocardiogram, and mean arterial pressure (MAP) were recorded simultaneously for 24 h once a week over 11 weeks. Wheel exercise was initiated in the SHRs at 12 weeks old and continued for another eight weeks. A significant suppression in the age-related elevation of MAP was noted in the SHRs undergoing wheel exercise. The reduction in MAP was correlated with increased parasympathetic activity and baroreflex sensitivity and decreased sympathetic activity, mainly during quiet sleep. Exercise increased the paradoxical sleep time and theta power (associated with cognitive function) but not the delta power (an indicator of sleep depth) or the attenuation of circadian rhythm flattening (characterized by increased wakefulness and less sleep during the light period and the opposite during the dark period). Furthermore, the exercise-induced changes in autonomic function occurred before those in sleep patterns, which were dependent on each other. In conclusion, wheel exercise can modulate sleep-related cardiovascular dysfunction and the flattening of circadian rhythm, preventing the progression of hypertension, which reduces the incidence of cardiovascular diseases.

Thiazide and thiazide-like diuretics: how to make the right choice?

Most patients with arterial hypertension (AH) require a combination treatment to achieve the goal blood pressure. According to Russian and international clinical guidelines on the treatment of AH patients, various antihypertensive drugs may be combined; however, not all combinations have similar profiles of safety and clinical efficacy. In this respect, special attention is given to combinations of renin-angiotensin-aldosterone system inhibitors and thiazide (hydrochlorothiazide) or thiazide-like (chlortalidone, indapamide) diuretics. Diuretics also differ in their mechanisms of action, presence of pleiotropic effects and organ-protective properties, effects on the prognosis, and in the evidence base. This review discusses the place of thiazide and thiazide-like diuretics in the treatment of patients with AH and provides an evaluation of major differences in pharmacological and clinical effects of drugs of the diuretic class.

Association between neighbourhood deprivation and hypertension in a US-wide Cohort

Background

Socioeconomic status (SES) at the individual level is associated with hypertension risk. Less is known about neighbourhood level SES or how neighbourhood and individual level SES may jointly affect hypertension risk.

Methods

The Area Deprivation Index (ADI) includes 17 census-based measures reflecting neighbourhood SES. The ADI was linked to enrolment addresses of 47 329 women in the Sister Study cohort and categorised as ≤10% (low deprivation), 11%–20%, 21%–35%, 36%–55% and >55% (high deprivation). Hypertension was defined as either high systolic (≥140 mm Hg) or diastolic (≥90 mm Hg) blood pressure or taking antihypertensive medication. We used log binomial regression to investigate the cross-sectional association between ADI and hypertension and evaluated interactions between ADI and race/ethnicity and between ADI and individual SES.

Results

The highest ADI level of >55% was associated with increased prevalence of hypertension, compared with the lowest level of ADI≤10%, in a model adjusted for age, race/ethnicity, educational attainment and annual household income (prevalence ratio=1.26, 95% CI 1.21 to 1.32). We observed interaction between race/ethnicity and ADI (interaction contrast ratio (ICR)=1.9; 95% CI 0.94 to 2.8 comparing non-Hispanic Black women with ADI >55% to non-Hispanic White women with ADI≤10%) and between household income and ADI (ICR 0.38; 95% CI 0.12 to 0.65 comparing participants with household income ≤US$49 999 and ADI>55% to those with household income >US$100 000 and ADI≤10%).

Conclusions

These findings suggest that neighbourhood deprivation measured by ADI may be a risk factor for hypertension and that ADI may act synergistically with race/ethnicity and individual household income to contribute to hypertension.

The association between blood metals and hypertension in the GuLF study

BACKGROUND

Both essential and non-essential metals come from natural and anthropogenic sources. Metals can bioaccumulate in humans and may impact human health, including hypertension.

METHODS

Blood metal (cadmium, lead, mercury, manganese, and selenium) concentrations were measured at baseline for a sample of participants in the Gulf Long-Term Follow-up (GuLF) Study. The GuLF Study is a prospective cohort study focused on potential health effects following the 2010 Deepwater Horizon oil spill. Hypertension was defined as high systolic (≥140 mm Hg) or diastolic (≥90 mm Hg) blood pressure or taking anti-hypertensive medications. A total of 957 participants who had blood measurement for at least one metal, baseline blood pressure measurements, information on any anti-hypertensive medication use, and relevant covariates were included in this cross-sectional analysis. We used Poisson regression to explore the association between individual blood metal levels and hypertension. Quantile-based g-computation was used to investigate the association between the metal mixture and hypertension. We also explored the association between individual blood metal levels and continuous blood pressure measurements using general linear regression.

RESULTS

Comparing the highest quartile of blood metals with the lowest (Q4vs1), the hypertension prevalence ratio (PR) was 0.92 (95 % confidence interval (CI) = 0.73,1.15) for cadmium, 0.86 (95%CI = 0.66,1.12) for lead, 0.89 (95%CI = 0.71,1.12) for mercury, 1.00 (95%CI = 0.80,1.26) for selenium, and 1.22 (95%CI = 0.95,1.57) for manganese. We observed some qualitative differences across race and BMI strata although none of these differences were statistically significant. In stratified analyses, the PR (Q4vs1) for mercury was 0.69 (95%CI = 0.53, 0.91) in White participants and 1.29 (95%CI = 0.86,1.92) in Black participants (p for interaction = 0.5). The PR (Q4vs1) for manganese was relatively higher in Black participants (PR = 1.37, 95%CI = 0.92,2.05) than in White participants (PR = 1.15, 95%CI = 0.83,1.60, p for interaction = 0.5), with a suggestive dose-response among Blacks. After stratifying by obesity (BMI ≥30 and < 30), positive associations of of hypertension with cadmium (PR [Q4vs1] = 1.19, 95%CI = 0.91,1.56, p for interaction = 0.5), lead (PR [Q4vs1] = 1.14, 95%CI = 0.84,1.55, p for interaction = 1.0) and manganese (PR = 1.25, 95%CI = 0.93,1.68, p for interaction = 0.8) were observed in participants with BMI≥30, but not in participants with BMI<30. The joint effect of the metal mixture was 0.96 (95%CI = 0.73,1.27). We did not observe clear associations between blood metal levels and continuous blood pressure measurements.

CONCLUSION

We did not find overall cross-sectional associations between blood cadmium, lead, mercury, selenium levels and hypertension or blood pressure. We found some evidence suggesting that manganese might be positively associated with risk of hypertension. Associations varied somewhat by race and BMI.

Airborne metals exposure and risk of hypertension in the Sister Study

BACKGROUND

Hypertension-related disease burden is a major challenge globally, with an estimated 1.56 billion adults expected to be affected by hypertension by 2025. Environmental factors, such as metals, could be risk factors for hypertension, but the relationship between airborne metals and hypertension is rarely studied.

METHODS

Census-tract airborne metal concentrations (arsenic, cadmium, chromium, cobalt, lead, manganese, mercury, nickel, selenium, and antimony) from the U.S. Environmental Protection Agency 2005 National Air Toxics Assessment database were linked to enrollment residential addresses of 47,595 women in the Sister Study cohort. Hypertension was defined as high systolic (≥140 mm Hg) or diastolic (≥90 mm Hg) blood pressure measured by trained examiners at enrollment or taking anti-hypertensive medications. Multivariable log binomial regression was used to estimate adjusted prevalence ratios (PRs) and 95% confidence intervals (CIs) for the association between individual metals and hypertension, with and without co-adjustment for other metals. Quantile-based g-computation was used to estimate the joint effect of the overall metal mixture.

RESULTS

Comparing the highest to lowest quartiles, risk of hypertension was higher among women with higher residential exposure to arsenic (PR = 1.05, 95%CI = 1.02,1.09), lead (PR = 1.04, 95%CI = 1.01,1.08), chromium (PR = 1.03, 95%CI = 1.00,1.06), cobalt (PR = 1.03, 95%CI = 1.00,1.07), and manganese (PR = 1.03, 95%CI = 1.00,1.06). Selenium was associated with lower risk of hypertension (PR = 0.96, 95%CI = 0.93,0.99). Results were similar with mutual adjustment for all other metals. The associations varied by race/ethnicity, with greater PRs in other races/ethnicities (Hispanic, black, and other participants) compared to non-Hispanic white participants. The joint effect of a quartile increase in exposure to all the metals was 1.02 (95%CI = 0.99,1.04).

CONCLUSION

We found that living in areas of higher exposure to arsenic, lead, chromium, cobalt, and manganese was related to higher risk of hypertension, whereas living in areas with higher selenium was inversely related to the risk of hypertension.

Practical application of the ATOM study: Treatment efficacy of antihypertensive drugs in monotherapy or combination (ATOM metaanalysis according to PRISMA statement); tables for the use of antihypertensive drugs in monotherapy or combination

BACKGROUND

The response to antihypertensive drugs is predictable. The absence of precise prescription recommendations to treat arterial hypertension (HT) lead to use drugs unable to reduce blood pressure (BP) to target values.We published ATOM study, in which we found significant differences in the ability to reduce BP between the different drugs.The objective of the study was to determine the expected decrease in blood pressure with the use of commercialized doses of the drugs commonly used in the treatment of HT in clinical practice, to avoid the use of drugs or combinations that even with the best response, are unable to obtain the necessary BP decrease to reach the goal.

METHODS

The analysis was based on the results of the ATOM study. To convert the mean doses of the different drugs and combinations in commercialized doses, the conclusions of the study by Law et al have been applied.

RESULTS

Based on the results, two tables were drawn, one for systolic BP and the other for diastolic BP, where the doses of the different drugs and combinations are classified according to the BP decrease that can be expected from them. In order to favor the use of the tables in clinical practice, the different drugs have been grouped in intervals of 10 millimeters of mercury (mmHg) for the decrease of the systolic BP and of 5 mmHg for the diastolic BP.

CONCLUSIONS

Recommendations for the use of antihypertensive treatments should not be limited to pharmacological families. They should also consider differences between drugs or specific combinations. From the data of the ATOM study we have implemented tables that express the effect of the drugs commonly used in clinical practice and that should allow the clinicians to choose with care the treatment to use.

Exercise and other nonpharmacological strategies to reduce blood pressure in older adults: a systematic review and meta-analysis

The incidence of hypertension increases with advancing age and represents a significant burden of disease. Lifestyle modification represents the first-line intervention in treatment algorithms; however, the majority of evidence for this comes from studies involving young participants using interventions that may not always be feasible in the elderly. This manuscript presents a systematic review of all randomized controlled trials involving participants with a mean age of 65 or over investigating nonpharmacological strategies to reduce blood pressure (BP). Fifty-three randomized controlled trials were included. The majority of interventions described aerobic exercise training, dynamic resistance exercise training, or combined aerobic and dynamic resistance exercise training (COM), with limited studies reporting isometric exercise training or alternative lifestyle strategies. Aerobic exercise training, dynamic resistance exercise training, COM, and isometric exercise training all elicited significant reductions in both systolic and diastolic BP, with no additional benefit of COM compared with single modality exercise training. Three months of traditional exercise-based lifestyle intervention may produce a reduction in BP of approximately 5 mmHg systolic and 3 mmHg diastolic in older individuals, similar to that expected in younger individuals.

Secondary hypertension in adults

Secondary hypertension occurs in a significant proportion of adult patients (~10%). In young patients, renal causes (glomerulonephritis) and coarctation of the aorta should be considered. In older patients, primary aldosteronism, obstructive sleep apnoea and renal artery stenosis are more prevalent than previously thought. Primary aldosteronism can be screened by taking morning aldosterone and renin levels, and should be considered in patients with severe, resistant or hypokalaemia-associated hypertension. Symptoms of obstructive sleep apnoea should be sought. Worsening of renal function after starting an angiotensin-converting enzyme inhibitor suggests the possibility of renal artery stenosis. Recognition, diagnosis and treatment of secondary causes of hypertension lead to good clinical outcomes and the possible reversal of end-organ damage, in addition to blood pressure control. As most patients with hypertension are managed at the primary care level, it is important for primary care physicians to recognise these conditions and refer patients appropriately.

Different associations between beta-blockers and other antihypertensive medication combinations with brachial blood pressure and aortic waveform parameters

BACKGROUND

Comparing the relationships of antihypertensive medications with brachial blood pressure (BP) and aortic waveform parameters may help clinicians to predict the effect on the latter in brachial BP-based antihypertensive therapy. We aimed to make such comparisons with new waveform measures and a wider range of antihypertensive regimens than examined previously.

METHODS

Cross-sectional analysis of 2933 adults (61% male; aged 50-84years): 1637 on antihypertensive treatment and 1296 untreated hypertensives. Sixteen medicine regimens of up to 4 combinations of drugs from 6 antihypertensive classes were analysed. Aortic systolic BP, augmentation index (AIx), excess pressure integral (EPI), backward pressure amplitude (Pb), reflection index (RI) and pulse wave velocity (PWV) were calculated from aortic pressure waveforms derived from suprasystolic brachial measurement.

RESULTS

Forest plots of single-drug class comparisons across regimens with the same number of drugs (for between 1- and 3-drug regimens) revealed that AIx, Pb, RI and/or loge(EPI) were higher (maximum difference=5.6%, 2.2mmHg, 0.0192 and 0.13 loge(mmHg⋅s), respectively) with the use of a beta-blocker compared with vasodilators and diuretics, despite no brachial systolic and diastolic BP differences. These differences were reduced (by 34-57%) or eliminated after adjustment for heart rate, and similar effects occurred when controlling for systolic ejection period or diastolic duration.

CONCLUSIONS

Beta-blocker effects on brachial BP may overestimate effects on aortic waveform parameters. Compared to other antihypertensives, beta-blockers have weaker associations with wave reflection measures and EPI; this is predominantly due to influences on heart rate.

Effects of telmisartan on fat distribution: a meta-analysis of randomized controlled trials

OBJECTIVES

Several meta-analyses have confirmed the positive metabolic effects of telmisartan, an angiotensin II receptor blocker that can also act as a partial peroxisome proliferator-activated receptor-γ agonist, compared to those of other angiotensin II receptor blockers. These effects include decreased fasting glucose, glycosylated hemoglobin, interleukin-6, and tumor necrosis factor-α levels. However, no systemic analysis of telmisartan's effects on body fat distribution has been performed. We performed a meta-analysis of randomized controlled telmisartan trials to investigate its effects on body weight, fat distribution, and visceral adipose reduction.

RESEARCH DESIGN AND METHODS

A literature search was performed using Embase, MEDLINE, and the Cochrane Library between January 1966 and November 2013. Randomized controlled trials in English and meeting the following criterion were included: random assignment of hypertensive participants with overweight/obesity, metabolic syndrome, or glucose intolerance to telmisartan or control therapy group.

RESULTS

Of 651 potentially relevant reports, 15 satisfied the inclusion criterion. While visceral fat area was significantly lower in the telmisartan group than in the control group (weighted mean difference = -18.13 cm(2), 95% C.I. = -27.16 to -9.11, Pχ(2) = 0.19, I(2) = 41%), subcutaneous fat area was similar (weighted mean difference =2.94 cm(2), 95% C.I. = -13.01 to 18.89, Pχ(2) = 0.30, I(2) = 17%). Total cholesterol levels were significantly different between the groups (standardized mean difference = -0.24, 95% C.I. = -0.45 to -0.03, Pχ(2) = 0.0002, I(2) = 67%).

LIMITATIONS

Limitations include: (1) limited number of studies, especially those evaluating fat distribution; (2) different imaging modalities to assess visceral fat area (V.F.A.) and subcutaneous fat area (S.F.A.); (3) observed heterogeneity.

CONCLUSION

The findings suggest that telmisartan affected fat distribution, inducing visceral fat reduction, and thus could be useful in hypertensive patients with obesity/overweight, metabolic syndrome, or glucose intolerance.

Treatment efficacy of anti-hypertensive drugs in monotherapy or combination: ATOM systematic review and meta-analysis of randomized clinical trials according to PRISMA statement

BACKGROUND

The relative efficacy of antihypertensive drugs/combinations is not well known. Identifying the most effective ones and the patients' characteristics associated with best performance of the drugs will improve management of hypertensive patients.

OBJECTIVE

To assess the blood pressure (BP) reduction attributed to antihypertensive drugs and identify characteristics associated with BP decrease.

DATA SOURCES

MEDLINE, Cochrane Central Register of Controlled Trials from inception through July 2012 and selected papers.

STUDY ELIGIBILITY CRITERIA

Double-blind, randomized clinical trials whose main result was the reduction in BP by antihypertensive treatment, with study population ≥50 or ≥25 if the study was a crossover, follow-up of at least 8 weeks, and available required data.

STUDY APPRAISAL AND SYNTHESIS METHODS

Study data were independently extracted by multiple observers and introduced in an electronic database. Inconsistencies were resolved by discussion and referral back to the original articles. Meta-analysis was performed according to PRISMA statement and using a Bayesian framework.

MAIN OUTCOME(S) AND MEASURE(S)

Mean decrease in systolic (SBP) and diastolic blood pressure (DBP) achieved by each drug or combination.

RESULTS

Two hundred eight trials including 94,305 patients were identified. In monotherapy, most drugs achieved 10 to 15 mm Hg SBP and 8 to 10 mm Hg DBP decreases.Olmesartan/amlodipine, olmesartan/hydrochlorothiazide, felodipine/metoprolol, and valsartan/hydrochlorothiazide were the combinations leading to the greatest mean SBP reductions (>20 mm Hg). Female sex and body mass index >25 kg/m were associated with more pronounced SBP and DBP reductions, whereas Afro-American ethnicity was associated with BP reductions smaller than the median. Results were adjusted by study duration, cardiovascular disease, and diabetes mellitus. Still, the estimation was performed using the mean administered doses, which do not exactly match those of the available drug formats.

LIMITATIONS

Data corresponded to those obtained in each of the included trials; the analysis of the combinations was limited to the most recent ones; estimations were performed using the mean administered doses.

CONCLUSIONS AND IMPLICATIONS

Certain drug combinations achieve BP reductions ranging from 20 to 25/10 to 15 mm Hg. Sex, ethnicity, and obesity are associated with antihypertensive response. This information can contribute to better selection of the antihypertensive drug, depending on the magnitude of pretreatment BP elevation. Guidelines should be revised.

Influence of initial angiotensin receptor blockers on treatment persistence in uncomplicated hypertension: A nation-wide population-based study

We identified 55 504 uncomplicated, treatment-naïve hypertensive patients who started angiotensin II receptor blockers (ARBs) in 2012 from national claims data. The proportion of patients remaining on any hypertension treatment at 12 months and the adherence rate were similar between the losartan cohort (66.82% and 68.25%) and the nonlosartan ARB cohort (67.48% and 69.01%). After adjusting for confounding factors, there was no difference in persistence (aHR 0.98, 95% confidence interval (CI) 0.95-1.01) on hypertension treatment between losartan and nonlosartan ARB cohort. Post hoc analysis showed that patients initially prescribed eprosartan, irbesartan (both, aHR 1.33), and telmisartan (aHR 1.11) were more likely to discontinue the initial drug, whereas valsartan initiators (aHR 0.96) were less likely compared with losartan initiators.

Treatment of Hypertensive Patients With Diabetes and Microalbuminuria With Combination Indapamide SR/Amlodipine: Retrospective Analysis of NESTOR

BACKGROUND

Combination treatments for hypertension most often include a renin-angiotensin-aldosterone system (RAAS) inhibitor. However, systolic blood pressure (SBP) remains difficult to control. Non-RAAS-inhibiting strategies such as calcium channel blocker/thiazide-like diuretic combinations may offer effective alternatives.

METHODS

Hypertensive diabetic patients with microalbuminuria were included in this retrospective, post-hoc analysis of the Natrilix SR Versus Enalapril Study in Hypertensive Type 2 Diabetics With MicrOalbuminuRia (NESTOR) trial if they were uncontrolled on monotherapy (indapamide slow release (SR) 1.5 mg or enalapril 10mg) and had been given add-on amlodipine 5 mg. Patients uncontrolled with monotherapy/amlodipine 5mg were uptitrated to 10 mg.

RESULTS

After 52 weeks, supine SBP/diastolic BP (DBP) decreased from baseline by 26±13/14±9 mm Hg in the indapamide SR/amlodipine group (n = 135) and by 21±14/11±9 mm Hg in the enalapril/amlodipine group (n = 156) (P = 0.006 for ΔSBP). In the amlodipine 10mg subgroup, SBP/DBP decreased from baseline by 26±13/13±9 mm Hg in the indapamide SR/amlodipine group (n = 62) and by 20±13/12±8 mm Hg in the enalapril/amlodipine group (n = 77) (P = 0.02 for ΔSBP). Treatment with indapamide SR/amlodipine was well tolerated. Few patients experienced edema, with no between-group differences. As expected with diuretics, slight changes in kalemia and in uricemia were observed in the indapamide SR/amlodipine group. Changes in fasting glucose, lipids, natremia, and creatinine clearance were similar between groups.

CONCLUSIONS

Indapamide SR/amlodipine results in superior SBP reduction with a safety profile in line with that of its components and tolerability equivalent to that of an angiotensin-converting enzyme inhibitor/amlodipine strategy.

Casein-derived lactotripeptides reduce systolic and diastolic blood pressure in a meta-analysis of randomised clinical trials

There is an urgent need to treat individuals with high blood pressure (BP) with effective dietary strategies. Previous studies suggest a small, but significant decrease in BP after lactotripeptides (LTP) ingestion, although the data are inconsistent. The study aim was to perform a comprehensive meta-analysis of data from all relevant randomised controlled trials (RCT). Medline, Cochrane library, EMBASE and Web of Science were searched until May 2014. Eligibility criteria were RCT that examined the effects of LTP on BP in adults, with systolic BP (SBP) and diastolic BP (DBP) as outcome measures. Thirty RCT met the inclusion criteria, which resulted in 33 sets of data. The pooled treatment effect for SBP was −2.95 mmHg (95% CI: −4.17, −1.73; p < 0.001), and for DBP was −1.51 mmHg (95% CI: −2.21, −0.80; p < 0.001). Sub-group analyses revealed that reduction of BP in Japanese studies was significantly greater, compared with European studies (p = 0.002 for SBP and p < 0.001 for DBP). The 24-h ambulatory BP (AMBP) response to LTP supplementation was statistically non-significant (p = 0.101 for SBP and p = 0.166 for DBP). Both publication bias and “small-study effect” were identified, which shifted the treatment effect towards less significant SBP and non-significant DBP reduction after LTP consumption. LTP may be effective in BP reduction, especially in Japanese individuals; however sub-group, meta-regression analyses and statistically significant publication biases suggest inconsistencies.

Thiazide-like/calcium channel blocker agents: a major combination for hypertension management

In recent years, treatment strategies for hypertension have often focused on combination therapies that include diuretics and renin angiotensin aldosterone system blockers such as angiotensin-converting enzyme inhibitors or angiotensin receptor blockers. However, in clinical practice, a significant number of patients do not respond completely to these combination treatments, and long-term reduction of cardiovascular risk remains insufficient. The particularly high residual cardiovascular risk of hypertensive patients, even when adequately treated with strategies based on renin angiotensin aldosterone system blockers, speaks in favor of new, innovative strategies. Thus, it has become relevant to consider whether it is always necessary to block plasma renin activation and whether other guideline-approved combinations should be considered routinely. Diuretic/calcium channel blocker combinations, which are supported by significant long-term evidence, are put forth as a preferred combination in the main guidelines, but are still underused by physicians who do not yet have easy access to such treatments. Fixed-dose indapamide sustained release/amlodipine is the first such single-pill combination to become available. Complementary mechanisms of action of these two molecules are expected to lead to greater and longer-term reductions in systolic blood pressure and pulse pressure and potentially to the reduction of cardiovascular risk.

Blood pressure control with a single-pill combination of indapamide sustained-release and amlodipine in patients with hypertension: the EFFICIENT study

OBJECTIVE

Despite antihypertensive treatment, most hypertensive patients still have high blood pressure (BP), notably high systolic blood pressure (SBP). The EFFICIENT study examines the efficacy and acceptability of a single-pill combination of sustained-release (SR) indapamide, a thiazide-like diuretic, and amlodipine, a calcium channel blocker (CCB), in the management of hypertension.

METHODS

Patients who were previously uncontrolled on CCB monotherapy (BP≥140/90 mm Hg) or were previously untreated with grade 2 or 3 essential hypertension (BP≥160/100 mm Hg) received a single-pill combination tablet containing indapamide SR 1.5 mg and amlodipine 5 mg daily for 45 days, in this multicenter prospective phase 4 study. The primary outcome was mean change in BP from baseline; percentage of patients achieving BP control (BP<140/90 mm Hg) was a secondary endpoint. SBP reduction (ΔSBP) versus diastolic BP reduction (ΔDBP) was evaluated (ΔSBP/ΔDBP) from baseline to day 45. Safety and tolerability were also assessed.

RESULTS

Mean baseline BP of 196 patients (mean age 52.3 years) was 160.2/97.9 mm Hg. After 45 days, mean SBP decreased by 28.5 mm Hg (95% CI, 26.4 to 30.6), while diastolic BP decreased by 15.6 mm Hg (95% CI, 14.5 to 16.7). BP control (<140/90 mm Hg) was achieved in 85% patients. ΔSBP/ΔDBP was 1.82 in the overall population. Few patients (n = 3 [2%]) reported side effects, and most (n = 194 [99%]) adhered to treatment.

CONCLUSION

In patients who were previously uncontrolled on CCB monotherapy or untreated with grade 2 or 3 hypertension, single-pill combination indapamide SR/amlodipine reduced BP effectively--especially SBP--over 45 days, and was safe and well tolerated.

TRIAL REGISTRATION

Clinical Trial Registry-India CTRI/2010/091/000114.

Telmisartan as a metabolic sartan: the first meta-analysis of randomized controlled trials in metabolic syndrome

Telmisartan has been proposed to be a promising cardiometabolic sartan due to its unique peroxisome proliferator-activated receptor-gamma-inducing property. To determine whether telmisartan improves metabolic parameters in metabolic syndrome, we perform the first meta-analysis of randomized controlled trials (RCTs). MEDLINE, EMBASE, and the Cochrane Central Register of Controlled Trials were searched through September 2012 using PubMed and OVID. Eligible studies were RCTs of telmisartan therapy enrolling individuals with metabolic syndrome and reporting metabolic parameters as outcomes. Of 31 potentially relevant articles screened initially, 10 reports of RCTs, enrolling a total of 546 patients with metabolic syndrome, were identified and included. Pooled analysis suggested significant reductions in % changes of fasting glucose (standardized mean difference, -0.51; 95% confidence interval [CI], -0.96 to -0.06; P = .03), insulin (-0.23; 95% CI, -0.40 to -0.06; P = .008), glycosylated hemoglobin (-0.26; 95% CI, -0.44 to -0.08; P = .005), and homeostasis model assessment index (-0.22; 95% CI -0.39 to -0.05; P = .01); and a significant increase in % changes of adiponectin (0.75; 95% CI, 0.40 to 1.09; P < .0001) among patients with metabolic syndrome randomized to telmisartan versus control therapy. Telmisartan therapy appears to significantly improve metabolic parameters in patients with metabolic syndrome.

Effectiveness and safety of the full-dose combination therapy with perindopril A and indapamide (10 mg/2,5 mg) in patients with arterial hypertension

Aim. To assess the effectiveness and safety of the full-dose combination therapy with perindopril (10 mg) and indapamide (2,5 mg) in patients with arterial hypertension (AH). Material and methods. The simple, non-randomised, prospective study included 36 patients with Stage 1-2 AH. Treatment effectiveness was assessed by the reduction in office blood pressure (BP) levels, results of the 24-hour BP monitoring (BPM), morning BP surge (MS), BP load area and time, BP variability, and diurnal index. Safety parameters included the levels of sodium, potassium, glucose, hepatic aminotransferases, urea, creatinine, and the presence of hypotension episodes. Statistical analysis was performed in SPSS 12. Results. The three-month therapy resulted in the achievement of target levels of systolic and diastolic BP (SBP, DBP) in 83% and 100% of the patients, respectively. According to the 24-hour BPM results, there was a significant reduction in the levels of SBP24 (from 148,3±18,2 to 134±11,1 mm Hg; p=0,001), DBP (from 84,8±12,3 to 76,9±9,1 mm Hg; p=0,001), and pulse BP (from 64,0±14,6 to 58,4±9,6 mm Hg; p=0,012). There was also a significant reduction in the load time indices of SBPday (from 72,5% (95% confidence interval, CI, 43,3-95,3) to 46,5% (95% CI 16,3-64,0); p=0,001) and DBPday (from 84,5% (54,0-100,0) to 57,0% (35,0-82,3); p=0,002). MS velocity decreased for both SBP (from 16,4 (12,5-25,1) to 12,7 (10,8-15,8) mm Hg (p=0,017) and DBP (from 15,8 (10,2-22,0) to 12,2 (9,3-17,8) mm Hg (p=0,019). During the therapy course, no hypotension episodes or marked changes in blood biochemistry and electrolyte parameters were registered. Conclusion. Initiating antihypertensive therapy with a full-dose combination of perindopril and indapamide was both effective and safe.

Metabolic effects of manidipine

The calcium channel antagonists (CCAs) were originally introduced as vasodilators for the treatment of coronary heart disease, but are now also noted for their clinical efficacy in the management of hypertension. Data from large clinical studies have shown that CCAs are not associated with the undesirable metabolic effects (e.g. worsening of dyslipidemia and reduction of insulin sensitivity) seen with older agents such as thiazide diuretics and beta-adrenoceptor antagonists (beta-blockers) that are used to treat hypertension. Indeed, reductions in cardiovascular risk and rates of onset of new cases of diabetes mellitus have been reported in trials in patients with hypertension treated with CCAs. These beneficial effects extend beyond those expected to accompany reductions in BP. Until recently, the biochemical effects underlying these metabolic changes were only poorly understood, but pharmacologic studies have now started to shed more light on these issues. Of particular interest are studies with manidipine, some of which suggest that this agent may be associated with greater improvements in insulin sensitivity and may have better renal protective properties than other CCAs. Confirmation of potential differences among CCAs in terms of the relative magnitude of any beneficial metabolic effects requires further study. Ongoing research is expected to clarify further the action of these agents at the cellular level and to assist with the optimization of antihypertensive therapy, particularly in patients with elevated cardiovascular risk profiles.

Effect of switching to a high-deductible health plan on use of chronic medications

OBJECTIVE

To examine whether high-deductible health plans (HDHPs) that exempt prescription drugs from full cost sharing preserve medication use for major chronic illness, compared with traditional HMOs with similar drug cost sharing.

DATA SOURCES/STUDY SETTING

We examined 2001-2008 pharmacy claims data of 3,348 continuously enrolled adults in a Massachusetts health plan for 9 months before and 24 months after an employer-mandated switch from a traditional HMO plan to a HDHP, compared with 20,534 contemporaneous matched HMO members. Both study groups faced similar three-tiered drug copayments. We calculated daily medication availability for all prescription drugs and four chronic medication classes: hypoglycemics, lipid-lowering agents, antihypertensives, and chronic obstructive pulmonary disease (COPD)/asthma controllers.

STUDY DESIGN

Interrupted time-series with comparison group study design examining monthly level and trend changes in prescription drug utilization.

PRINCIPAL FINDINGS

The HDHP and control groups had comparable changes in the level and trend of all drugs after the index date; we detected similar patterns in the use of lipid-lowering agents, antihypertensives, and COPD/asthma controllers. Some evidence suggested a small relative decline in hypoglycemic use among diabetic patients in HDHPs.

CONCLUSIONS

Switching to an HDHP that included modest drug copayments did not change medication availability or reduce use of essential medications for three common chronic illnesses.

Efficacy of aliskiren/hydrochlorothiazide combination for the treatment of hypertension: a meta-analytical approach

BACKGROUND

Single-pill combinations of aliskiren/hydrochlorothiazide have recently been approved by the European Medicines Agency for the treatment of hypertension.

OBJECTIVE

This study aimed to assess the antihypertensive efficacy of aliskiren/hydrochlorothiazide combination in reducing systolic and diastolic blood pressure in hypertensive patients.

METHODS

A search in International Pharmaceutical Abstracts, MEDLINE, The Cochrane Library and ISI Web of Knowledge was performed from 2000 to November 2009, to identify randomized, double-blind, clinical trials using aliskiren/hydrochlorothiazide for the treatment of hypertension. Studies were included if they evaluated the antihypertensive efficacy of aliskiren/hydrochlorothiazide in patients with mild or moderate essential hypertension and age ≥ 18 years. The meta-analytical approach calculated the weighted average reductions of systolic and diastolic blood pressure for each daily dosage combination.

RESULTS

We included 5 clinical trials testing several combinations of aliskiren/hydrochlorothiazide and containing data on 5448 patients. In all studies blood pressure was assessed at inclusion (baseline) and after 8 weeks of therapy. Blood pressure reductions and control rates were significantly (p < 0.05) higher with the aliskiren/hydrochlorothiazide combinations than with placebo and the same doses of aliskiren or hydrochlorothiazide alone. The weighted mean reductions (mm Hg) from baseline of systolic and diastolic blood pressure for each aliskiren/hydrochlorothiazide combination were: -15.8/-10.3 (150/25 mg); -15.9/-11.8 (300/12.5 mg); -16.9/-11.6 (300/25 mg). Blood pressure control rates (%) for the above combinations were, at least, respectively: 43.8, 50.1 and 51.9.

CONCLUSIONS

Aliskiren/hydrochlorothiazide provided clinically significant additional blood pressure reductions and improved blood pressure control rates over aliskiren or hydrochlorothiazide monotherapy.

Effectiveness, safety and cost of drug substitution in hypertension

Cost-containment measures in healthcare provision include the implementation of therapeutic and generic drug substitution strategies in patients whose condition is already well controlled with pharmacotherapy. Treatment for hypertension is frequently targeted for such measures. However, drug acquisition costs are only part of the cost-effectiveness equation, and a variety of other factors need to be taken into account when assessing the impact of switching antihypertensives. From the clinical perspective, considerations include maintenance of an appropriate medication dose during the switching process; drug equivalence in terms of clinical effectiveness; and safety issues, including the diverse adverse-event profiles of available alternative drugs, differences in the 'inactive' components of drug formulations and the quality of generic formulations. Patients' adherence to and persistence with therapy may be negatively influenced by switching, which will also impact on treatment effectiveness. From the economic perspective, the costs that are likely to be incurred by switching antihypertensives include those for additional clinic visits and laboratory tests, and for hospitalization if required to address problems arising from adverse events or poorly controlled hypertension. Indirect costs and the impact on patients' quality of life also require assessment. Substitution strategies for antihypertensives have not been tested in large outcome trials and there is little available clinical or economic evidence on which to base decisions to switch drugs. Although the cost of treatment should always be considered, careful assessment of the human and economic costs and benefits of antihypertensive drug substitution is required before this practice is recommended.

Economic evaluation of home blood pressure monitoring with or without telephonic behavioral self-management in patients with hypertension

BACKGROUND

The Take Control of Your Blood Pressure trial evaluated the effect of a multicomponent telephonic behavioral lifestyle intervention, patient self-monitoring, and both interventions combined compared with usual care on reducing systolic blood pressure during 24 months. The combined intervention led to a significant reduction in systolic blood pressure compared with usual care alone. We examined direct and patient time costs associated with each intervention.

METHODS

We conducted a prospective economic evaluation alongside a randomized controlled trial of 636 patients with hypertension participating in the study interventions. Medical costs were estimated using electronic data representing medical services delivered within the health system. Intervention-related costs were derived using information collected during the trial, administrative records, and published unit costs.

RESULTS

During 24 months, patients incurred a mean of $6,965 (s.d., $22,054) in inpatient costs and $8,676 (s.d., $9,368) in outpatient costs, with no significant differences among the intervention groups. With base-case assumptions, intervention costs were estimated at $90 (s.d., $2) for home blood pressure monitoring, $345 (s.d., $64) for the behavioral intervention ($31 per telephone encounter), and $416 (s.d., $93) for the combined intervention. Patient time costs were estimated at $585 (s.d., $487) for home monitoring, $55 (s.d., $16) for the behavioral intervention, and $741 (s.d., $529) for the combined intervention.

CONCLUSIONS

Our analysis demonstrated that the interventions are cost-additive to the health-care system in the short term and that patients' time costs are nontrivial.

Treating hypertension by rational use of diuretics: results of the Russian ARGUS-2 Study

OBJECTIVE

Insufficient use of diuretics in combination antihypertensive therapy is a main cause of poor blood pressure (BP) control in Russia. The objective of the ARGUS-2 study was to demonstrate that a rational use of a thiazide-like diuretic, indapamide sustained release (SR), alone or in combination, improves BP control in patients with arterial hypertension difficult to control due to isolated systolic hypertension (ISH), diabetes mellitus (DM), chronic nephropathy, or metabolic syndrome.

METHODS

The open-label, non-comparative, 3-month study without preliminary washout included 1438 hypertensive patients (mean age: 57.3 +/- 10.7 years, mean BP: 158.8 +/- 14.2/93.4 +/- 10.0 mmHg), with difficult-to-control arterial hypertension and who had never been treated with diuretics previously. Throughout the study, patients received indapamide SR 1.5 mg OD. BP control was defined as <140/90 mmHg for all patients and <130/80 mmHg for those with diabetes mellitus or chronic nephropathy.

RESULTS

Indapamide SR was given as initiation monotherapy to 13.7% of the patients, as substitutive monotherapy to 6.8% of the patients uncontrolled by a previous monotherapy, as additive therapy to 31.9% of the patients uncontrolled by previous monotherapy, and as additive therapy to 47.6% uncontrolled by previous combination therapy without a diuretic. Among included patients 75.7% received also an ACE inhibitor or an angiotensin II receptors blocker, 43.9% a calcium channel blocker, and 32.8% a beta-blocker. In 3 months after indapamide SR administration, average BP level decreased to 131.8 +/- 9.7/80.5 +/- 6.9 mmHg and 84.5% of the study population achieved BP control. BP was controlled in 91.9% of patients with ISH (n = 477), 74.8% of those with diabetes (n = 214), 75.6% of those with chronic nephropathy (n = 82), and 85.1% of patients with metabolic syndrome (n = 745). No case of hypokalemia was reported.

CONCLUSION

The study demonstrates the value of including the thiazide-like diuretic indapamide SR in a combined antihypertensive regimen to control BP in hypertensive patients with added cardiovascular risk factors whose hypertension is difficult to treat. Methodological limitations of this study are its open-label design and the possibility of a change in concomitant antihypertensive treatment during the study.

Valsartan vs. other angiotensin II receptor blockers in the treatment of hypertension: a meta-analytical approach

OBJECTIVE

To compare the efficacy of valsartan in systolic (SBP) and diastolic blood pressure (DBP) reduction with other angiotensin II receptor blockers (ARBs) in essential hypertension.

METHODS

Systematic literature search of databases between October 1997 and May 2008. Meta-analysis of short-term, double-blind, parallel group, randomised controlled trials (RCTs) for treatment of adult hypertension (DBP: 90-115 mmHg). Random-effects meta-regression adjusting for baseline blood pressure (BP) was used to analyse the data. Mean change in SBP and DBP was estimated for each individual drug and dose combination.

RESULTS

In all, 31 RCTs (n = 13,110 patients) were included in the analysis. Six studies include trial arms with candesartan, six irbesartan, 13 losartan, two olmesartan, five telmisartan and 12 valsartan. The weighted average reduction in mean SBP and DBP for valsartan 160 mg was -15.32 mmHg (95% CI: -17.09, -13.63) and -11.3 mmHg (95% CI: -12.15, -10.52) and for 320 mg was -15.85 mmHg (95% CI: -17.60, -14.12) and -11.97 mmHg (95% CI: -12.81, -11.16); these are statistically significantly greater reductions compared with losartan 100 mg, which was -12.01 mmHg (95% CI: -13.78, -10.25) and -9.37 mmHg (95% CI: -10.18, -8.54) for SBP and DBP respectively. There is evidence that valsartan 160 mg reduces SBP and DBP more than irbesartan 150 mg and reduced DBP more than candesartan 16 mg. No other statistically significant difference in efficacy is demonstrated.

CONCLUSION

Valsartan administered at 160 or 320 mg is more effective at lowering BP than losartan 100 mg and shows comparable efficacy to other ARBs in patients with essential hypertension.

Telmisartan versus angiotension-converting enzyme inhibitors in the treatment of hypertension: a meta-analysis of randomized controlled trials

Telmisartan and angiotensin-converting enzyme inhibitors (ACEIs) are both effective and widely used antihypertensive drugs targeting renin-angiotensin-aldosterone system. The study aimed to estimate the efficacy and tolerability of telmisartan in comparison with different ACEIs as monotherapy in the treatment of hypertension. Cochrane Central Register of Controlled Trials, PubMed and Embase were searched for relevant studies. A meta-analysis of all randomized controlled trials fulfilling the predefined criteria was performed. A random-effect model was used to account for heterogeneity among trials. Twenty-eight randomized controlled trials involving 5157 patients were ultimately identified out of 721 studies. Telmisartan had a greater diastolic blood pressure (DBP) reduction than enalapril (weighted mean difference (WMD) 1.82, 95% confidence interval (CI) 0.66-2.99), ramipril (WMD 3.09, 95% CI 1.94-4.25) and perindopril (WMD 1.48, 95% CI 0.33-2.62). Telmisartan also showed a greater DBP response rate than enalapril (relative risk (RR) 1.15, 95% CI 1.05-1.26), ramipril (RR 1.34, 95% CI 1.11-1.61) and perindopril (RR 1.22, 95% CI 1.05-1.41). There was no statistical difference in DBP reduction or therapeutic response rate between telmisartan and lisinopril (WMD -0.30, 95% CI -0.65 to 0.05; RR 0.99, 95% CI 0.80-1.23, respectively). Telmisartan had fewer drug-related adverse events than enalapril (RR 0.57, 95% CI 0.44-0.74), ramipril (RR 0.44, 95% CI 0.26-0.75), lisinopril (RR 0.70, 95% CI 0.56-0.89) and perindopril (RR 0.52, 95% CI 0.28-0.98). The meta-analysis indicates that telmisartan provides a superior BP control to ACEIs (enalapril, ramipril and perindopril) and has fewer drug-related adverse events and better tolerability in hypertensive patients.

Cost-effectiveness of irbesartan/hydrochlorothiazide in patients with hypertension: an economic evaluation for Sweden

Irbesartan, an angiotensin-II inhibitor, has been shown to be an effective antihypertensive agent in clinical trials. The purpose of this study was to assess the cost-effectiveness of irbesartan in combination with hydrochlorothiazide (HCTZ) in Swedish health-care setting by predicting clinical events and life years based upon observed reductions in blood pressure in clinical trials. The cost-effectiveness of antihypertensive treatment with irbesartan compared with placebo and to other selected angiotensin-II inhibitors (losartan, valsartan, candesartan) in combination with HCTZ was estimated using a Markov model. The incidence of cardiovascular disease was obtained from the Swedish inpatient registry, whereas the risk reductions associated with antihypertensive therapy were taken from the medical literature. Costs for antihypertensive therapy and for treatment of cardiovascular events were included, and the health effects were measured in terms of quality-adjusted life years (QALYs). The study was conducted from a health-care payer perspective. For a 55-year-old male, irbesartan 150 mg/HCTZ 12.5 mg was a dominant strategy (better health effects at lower costs) when compared with losartan 50 mg/HCTZ 12.5 mg and valsartan 80 mg/HCTZ 12.5 mg, and the cost-effectiveness ratio compared with placebo was 3500 euros per QALY gained. In moderate-to-severe hypertension, irbesartan was cost-effective compared with losartan, whereas the results compared with candesartan were mixed. High-dose combination therapy of irbesartan was also found to be cost-effective compared with low-dose combination therapy. The results from the model indicate that irbesartan provides a cost-effective antihypertensive treatment strategy compared with both placebo, and to valsartan and losartan.

Effect of garlic on blood pressure: a systematic review and meta-analysis

Background

Non-pharmacological treatment options for hypertension have the potential to reduce the risk of cardiovascular disease at a population level. Animal studies have suggested that garlic reduces blood pressure, but primary studies in humans and non-systematic reviews have reported mixed results. With interest in complementary medicine for hypertension increasing, it is timely to update a systematic review and meta-analysis from 1994 of studies investigating the effect of garlic preparations on blood pressure.

Methods

We searched the Medline and Embase databases for studies published between 1955 and October 2007. Randomised controlled trials with true placebo groups, using garlic-only preparations, and reporting mean systolic and/or diastolic blood pressure (SBP/DBP) and standard deviations were included in the meta-analysis. We also conducted subgroup meta-analysis by baseline blood pressure (hypertensive/normotensive), for the first time. Meta-regression analysis was performed to test the associations between blood pressure outcomes and duration of treatment, dosage, and blood pressure at start of treatment.

Results

Eleven of 25 studies included in the systematic review were suitable for meta-analysis. Meta-analysis of all studies showed a mean decrease of 4.6 ± 2.8 mm Hg for SBP in the garlic group compared to placebo (n = 10; p = 0.001), while the mean decrease in the hypertensive subgroup was 8.4 ± 2.8 mm Hg for SBP (n = 4; p < 0.001), and 7.3 ± 1.5 mm Hg for DBP (n = 3; p < 0.001). Regression analysis revealed a significant association between blood pressure at the start of the intervention and the level of blood pressure reduction (SBP: R = 0.057; p = 0.03; DBP: R = -0.315; p = 0.02).

Conclusion

Our meta-analysis suggests that garlic preparations are superior to placebo in reducing blood pressure in individuals with hypertension.

Switch strategies in the management of hypertension: a cost minimisation analysis of angiotensin receptor blocker based regimen

BACKGROUND AND OBJECTIVE

Budgetary pressures within health care systems have led many health care providers to consider the switching of patients on long term anti hypertensive medication to agents with the lowest acquisition price. The long term success of this strategy hinges on price differentials remaining stable, an assumption that may not be valid in drug classes where patent expiry times vary. The treatment of hypertension using angiotensin receptor blockers (ARBs) represents just such a case. The present study, therefore, modelled the 5-year cost consequences of treatment based on losartan, candesartan, valsartan and irbesartan, based on expected patent expiry dates.

METHODS

A Markov model was constructed, applying dose-specific blood-pressure lowering and costs to a cohort of uncontrolled mild-moderate hypertensive patients and assessing the anticipated cost of treatment over a 5 year period. A probabilistic approach was adopted to account for between-patient and between-treatment differences.

RESULTS

For both undiscounted and discounted models, a losartan-based regimen represents the least costly option of the four agents tested. Median (IQR) discounted expenditure per patient for each agent was: losartan: pound 506 ( pound 441- pound 650), candesartan: pound 610 ( pound 542- pound 766), valsartan: pound 809 ( pound 796- pound 1078), irbesartan pound 696 ( pound 694- pound 934).

CONCLUSION

Switching hypertensive patients taking ARBs to the agent with the lowest current acquisition cost may yield only transient budgetary savings. Once patent expiry is taken into account, this model suggests that maintaining or switching patients to losartan would yield considerably greater savings over 5 years.