Lowering blood pressure for cardiovascular risk reduction
The association between blood pressure and cardiovascular risk is continuous, with no known lower threshold; epidemiologically, the lower the blood pressure, the better. In reality, the relationship must be J- or U-shaped, as a blood pressure of zero is associated with 100% mortality. However, the level of blood pressure control below which risk increases is well below that achieved in clinical practice, and reducing blood pressure is a cornerstone of strategies to reduce cardiovascular risk. Even relatively small reductions in blood pressure (systolic blood pressure 10–12 mmHg, diastolic blood pressure 5–6 mmHg) substantially reduce cardiovascular risk. Optimal cardiovascular protection is achievable through early and aggressive blood pressure control, but precisely which agents confer the greatest benefits for cardiovascular protection remains widely debated. Angiotensin II receptor blockers (ARBs) appear to be unique in providing additional protection beyond blood pressure control, whereas similar claims for other agents do not withstand close scrutiny. Nearly all patients with hypertension require several antihypertensive treatments to reach their target blood pressure, and it is important to choose treatments that are well tolerated and have complementary modes of action. For this reason, ARBs such as telmisartan emerge as logical choices for combination therapy, particularly when combined with a diuretic, as they fulfil all the essential requirements for combination therapy and are effective in a wide range of different types of patient. Regrettably, a rigorous approach to blood pressure control using multiple agents is still rare in general practice, partly because of a lack of understanding and partly because of ‘professional non-compliance’. Prescribing habits must change, and soon, if we are to avoid an upsurge in cardiovascular complications.