AsPac heart experts tackle hypertension

Control of blood pressure remains woefully inadequate in the Asia-Pacific region.

This was the big concern of heart specialists who gathered in Hong Kong recently to discuss the various issues and concerns in the management of hypertension in the region. The highly interactive forum called ROLF (Regional Opinion Leaders Forum) gathered the region’s top opinion leaders to help identify these problems and offer solutions.

ROLF’s overall chairman was Filipino cardiologist Dr. Rafael Castillo. The forum gathered prominent heart specialists in the region such as Professors Brian Tomlinson (Hong Kong), Peera Buranakitjaroen (Bangkok), Harmani Kalim (Jakarta), Melvin Tan (Singapore), Chuen-Den Tseng (Taipei), Cai Naisheng (Shanghai) and Dang Van Phuoc (Ho Chi Minh). Prof. Peter Sleight from Oxford, England was invited as guest resource person.

Barriers to optimal management identified by the ROLF participants included lack of familiarity with management guidelines among physicians, an apparent disparity between what physicians say they do and what they actually do in clinical practice, poor patient compliance, and the high cost of newer antihypertensive agents.

Based on the various lectures and discussions, calcium channel blockers (CCBs) remain the most frequently prescribed antihypertensive drugs in the region. Other classes of drugs such as angiotensin-converting enzyme (ACE) inhibitors and angiotensin II receptor blockers (ARBs) continue to grow dynamically in terms of prescription which would indicate dominance of these classes of drugs in the future.

Landmark trials

Results from landmark trials including the Heart Outcomes Prevention Evaluation (HOPE) and the Perindopril Protection Against Recurrent Stroke Study (PROGRESS) were presented, showing clear benefits with the use of ACE inhibitors even in those with normal blood pressure but are high-risk patients due to the presence of other risk factors such as diabetes mellitus, elevated cholesterol levels, metabolic syndrome characterized by obesity, elevated triglycerides and blood sugar and low high-density lipoprotein (good cholesterol).

The forum also discussed the emerging role of angiotensin receptor blockers in the treatment of hypertension and various cardiovascular diseases. Combination therapy of an ARB and an ACE inhibitor is also an exciting possibility.

The Ongoing Telmisartan Alone and in combination with Ramipril Global Endpoint Trial (ONTARGET) will be the largest ARB clinical trial ever conducted (about 8,000 patients in each arm). This study will compare the efficacy of the ARB telmisartan with ramipril in preventing cardiovascular morbidity and mortality, and determine any additional benefit of combining telmisartan with ramipril, compared with the ACE inhibitor alone.

Results of studies showing the efficacy of the fixed-dose combination of telmisartan and hydochlorothiazide (Micardis Plus) were also presented. These studies support the complementary effect of these two antihypertensives with more efficacy without adversely affecting tolerability. The cost of treatment can also be minimized with the fixed-dose combination which, according to some forum participants, can improve patient compliance.

Cost factor

There was a consensus among the participants that cost is an important factor in determining antihypertensive prescription. But there are also minimum requirements for antihypertensives before they can be prescribed (i.e. solid clinical data showing blood pressure-lowering efficacy and other clinical benefits).

The participants agreed that first-line therapy for hypertension should be individualized according to the patient’s risk profile and associated illnesses or comorbidities. They also agreed that organ protection is a very important aspect of antihypertensive therapy. An antihypertensive agent that can effectively lower blood pressure should be able to protect the heart, brain, kidney and other vital organs which, in turn, can be expected to confer long-term clinical benefits to the patient in terms of lower incidence of heart attack, stroke and cardiovascular death.

The forum was organized by Adis International, a publication organization based in New Zealand, through a continuing medical education grant from Boehringer Ingelheim International.