Treatment of hypertension in peripheral arterial disease

Study of risk factors associated with peripheral arteriopathy in Japanese-Brazilians from Bauru (SP)

BACKGROUND

Cardiovascular diseases are the major cause of morbidity and mortality in developed and emerging countries. Their main etiology, atherosclerosis, is a disseminated disease that affects the coronary, cerebral and peripheral territories. The peripheral arterial disease (PAD), as well as its consequences, indicates the involvement of the coronary territory. Therefore, its better understanding enables proper treatment, delaying local and long-term complications, reducing the cost to the health system.

OBJECTIVE

This study estimates the percentage of PAD in Japanese-Brazilians from Bauru (SP), recognized by the high prevalence of metabolic disorders such as hypertension (43%), diabetes mellitus (33%) and hypercholesterolemia (60%), and examines the association with risk biomarkers.

METHODS

This cross-sectional population study evaluated 1,330 Japanese-Brazilians of both genders aged≥30 who underwent a complete physical examination, anthropometric measurements, laboratory tests and ankle-brachial index (ABI). Participants with ABI≤0.90 were diagnosed as having PAD. After applying the exclusion criteria, 1,038 individuals were part of the analysis. We used Poisson regression to analyze associations with PAD.

RESULTS

The mean age was 56.8 years and the percentage of PAD was 21.1%, equal among the genders. PAD was associated with smoking (PR 2.16 [1.33 to 3.48]) and hypertension (PR 1.56 [1.12-2.22]).

CONCLUSION

The percentage of PAD in Japanese-Brazilians was similar to other populations of adverse cardiometabolic profile (US PARTNERS and POPADAD). The independent association of PAD with smoking and hypertension, but not with other classical risk factors, may depend on the very high frequencies of metabolic disorders in this population.

Treatment of hypertension in peripheral arterial disease

BACKGROUND

Peripheral arterial disease (PAD) causes considerable morbidity and mortality. Hypertension is a risk factor for PAD. Treatment for hypertension must be compatible with the symptoms of PAD. Controversy regarding the effects of beta-adrenoreceptor blockade for hypertension in patients with PAD has led many physicians to stop prescribing beta-adrenoreceptor blockers. Little is known about the effects of other classes of anti-hypertensive drugs in the presence of PAD. This is the second update of a Cochrane review first published in 2003.

OBJECTIVES

To determine the effects of anti-hypertensive drugs in patients with both raised blood pressure and symptomatic PAD in terms of the rate of cardiovascular events and death, symptoms of claudication and critical leg ischaemia, and progression of atherosclerotic PAD as measured by ankle brachial index (ABI) changes and the need for revascularisation (reconstructive surgery or angioplasty) or amputation.

SEARCH METHODS

For this update the Cochrane Peripheral Vascular Diseases Group Trials Search Co-ordinator searched the Cochrane Peripheral Vascular Diseases Group Specialised Register (last searched March 2013) and CENTRAL (2013, Issue 2).

SELECTION CRITERIA

Randomised controlled trials (RCTs) of at least one anti-hypertensive treatment against placebo or two anti-hypertensive medications against each other, with interventions lasting at least one month. Trials had to include patients with symptomatic PAD.

DATA COLLECTION AND ANALYSIS

Data were extracted by one author (DAL) and checked by the other (GYHL). Potentially eligible studies were excluded when the results presentation prevented adequate extraction of data and enquiries to authors did not yield raw data.

MAIN RESULTS

Eight RCTs were included with a total of 3610 PAD patients. Four studies compared a recognised class of anti-hypertensive treatment with placebo and four studies compared two anti-hypertensive treatments with each other. Studies were not pooled due to the variation of the comparisons and the outcomes presented. Overall the quality of the available evidence was unclear, primarily as a result of a lack of detail in the study reports on the randomisation and blinding procedures and incomplete outcome data. Two studies compared angiotensin converting enzyme (ACE) inhibitors against placebo. In one study there was a significant reduction in the number of cardiovascular events in patients receiving ramipril (odds ratio (OR) 0.72, 95% confidence interval (CI) 0.58 to 0.91; n = 1725). In the second trial using perindopril (n = 52) there was a marginal increase in claudication distance but no change in ABI and a reduction in maximum walking distance. A trial comparing the calcium antagonist verapamil versus placebo in patients undergoing angioplasty (n = 96) suggested that verapamil reduced restenosis (per cent diameter stenosis (± SD) 48.0% ± 11.5 versus 69.6% ± 12.2; P < 0.01), although this was not reflected in the maintenance of a high ABI (0.76 ± 0.10 versus 0.72 ± 0.08 for verapamil versus placebo). Another study (n = 80) demonstrated no significant difference in arterial intima-media thickness (IMT) in men receiving the thiazide diuretic hydrochlorothiazide (HCTZ) compared to those receiving the alpha-adrenoreceptor blocker doxazosin (-0.12 ± 0.14 mm and -0.08 ± 0.13 mm, respectively; P = 0.66). A study (n = 36) comparing telmisartan to placebo found a significant improvement in maximum walking distance at 12 months with telmisartan (median (interquartile range (IQR)) 191 m (157 to 226) versus 103 m (76 to 164); P < 0.001) but no differences in ABI (median (IQR) 0.60 (0.60 to 0.77) versus 0.52 (0.48 to 0.67)) or arterial IMT (median (IQR) 0.08 cm (0.07 to 0.09) versus 0.09 cm (0.08 to 0.10)). Two studies compared the beta-adrenoreceptor blocker nebivolol with either the thiazide diuretic HCTZ or with metoprolol. Both studies found no significant differences in intermittent or absolute claudication distance, ABI, or all-cause mortality between the anti-hypertensives. A subgroup analysis of PAD patients (n = 2699) in a study which compared a calcium antagonist-based strategy (verapamil slow release (SR) ± trandolapril) to a beta-adrenoreceptor blocker-based strategy (atenolol ± hydrochlorothiazide) found no significant differences in the composite endpoints of death, non-fatal myocardial infarction or non-fatal stroke with or without revascularisation (OR 0.90, 95% CI 0.76 to 1.07 and OR 0.96, 95% CI 0.82 to 1.13, respectively).

AUTHORS' CONCLUSIONS

Evidence on the use of various anti-hypertensive drugs in people with PAD is poor so that it is unknown whether significant benefits or risks accrue. However, lack of data specifically examining outcomes in PAD patients should not detract from the overwhelming evidence on the benefit of treating hypertension and lowering blood pressure.

Treatment of hypertension in peripheral arterial disease

BACKGROUND

Peripheral arterial disease (PAD) causes considerable morbidity and mortality. Hypertension is a risk factor for PAD. Treatment for hypertension must be compatible with the symptoms of PAD. Controversy regarding the effects of beta-blockade for hypertension in patients with PAD has led many physicians to stop prescribing beta-blockers. Little is known about the effects of other classes of anti-hypertensive drugs in the presence of PAD. This is an update of a Cochrane review first published in 2003.

OBJECTIVES

To determine the effects of anti-hypertensive drugs on cardiovascular events and death, symptoms of claudication, critical leg ischaemia, progression of PAD and revascularisation or amputation in people with hypertension and PAD SEARCH STRATEGY: The Cochrane Peripheral Vascular Diseases Group searched their Specialised Register (last searched May 2009) and the Cochrane Central Register of Controlled Trials (The Cochrane Library 2009, Issue 2). The authors studied abstracts of cardiology meetings.

SELECTION CRITERIA

Randomised controlled trials of at least one anti-hypertensive treatment against placebo, or two anti-hypertensive medications against each other, with interventions lasting at least one month. Trials had to include patients with symptomatic PAD.

DATA COLLECTION AND ANALYSIS

Data were extracted by one author (DAL) and checked by the other (GYHL). Eligible studies were excluded when results presentation prevented adequate extraction of data and enquiries to authors did not yield raw data.

MAIN RESULTS

Four studies were included. Two compared ACE inhibitors against placebo. In the HOPE study there was a significant reduction in the number of cardiovascular events in 168 patients receiving ramipril (OR 0.72, 95% confidence interval 0.58 to 0.91). In the second trial using perindopril in a small numbers of patients, there was a marginal increase in claudication distance but no change in ankle brachial pressure index (ABPI) and a reduction in maximum walking distance.The third trial in patients undergoing angioplasty suggested that the calcium antagonist verapamil reduced restenosis, although this was not reflected in the maintenance of a high ABPI. Another small study demonstrated no significant difference in arterial intima-media thickness with men receiving the thiazide diuretic hydrochlorathiazide compared to those receiving the alpha-adrenoreceptor blocker doxazosin.

AUTHORS' CONCLUSIONS

Evidence on various anti-hypertensive drugs in people with PAD is poor so that it is unknown whether significant benefits or risks accrue from their use. Lack of data specifically examining outcomes in PAD patients should not detract from the compelling evidence of the benefit of treating hypertension and lowering blood pressure.

Atherosclerotic risk factor control in patients with peripheral arterial disease

BACKGROUND

The presence of peripheral arterial disease (PAD), even in the absence of overt coronary artery disease (CAD), confers the same relative risk of death from a cardiovascular cause as in patients with a previous cardiovascular event. Current guidelines recommend atherosclerotic risk factor-reduction strategies in PAD patients identical to those in patients with a recent coronary event. The purpose of this study was to determine the status of atherosclerotic risk factor control in patients with PAD.

METHODS

We analyzed the records of patients treated at 2 regional clinics serving 92,940 individuals. Full examination, laboratory, and pharmacy data were available for all patients. Pharmacy data were analyzed to determine prescriptions for beta-blocker therapy, angiotensin-converting enzyme inhibitors, and lipid-lowering agents. Lipid control was assessed through fasting lipid data. Glycemic control in diabetics was evaluated by using hemoglobin A 1c levels.

RESULTS

We administratively identified 2839 patients with a diagnosis of PAD. The exclusion of 1106 patients with a diagnosis of CAD or validated not to have PAD resulted in a cohort of 1733 patients. Of these, 33.1% (574/1733) were currently receiving beta-blockers, 28.9% (500/1733) were receiving an angiotensin-converting enzyme inhibitor, and 31.3% (543/1733) were receiving a statin. Most patients (92%; 1594/1733) had a recent blood pressure recorded. However, 56% (893/1594) had a systolic blood pressure of 130 mm Hg or higher, 45.5% (726/1594) had a diastolic blood pressure of 80 mm Hg or higher, and 13.6% (217/1594) had a diastolic blood pressure of 90 mm Hg or higher. Screening fasting lipid profiles were found in 62.6% (1085/1733) of patients, 56% (508/912) had a low-density lipoprotein of 100 mg/dL or higher, and 21% (187/912) had a value of more than 130 mg/dL. In patients with diabetes, a hemoglobin A 1c level of 7.0% or higher was found in 54.2% (198/365) of patients.

CONCLUSIONS

Despite national consensus of PAD as a CAD equivalent, patients are currently undertreated with regard to atherosclerotic risk factor modification. Until broader recognition of this disease process exists, vascular surgeons must continue to champion medical as well as surgical treatments for these patients.