Cardiovascular disease causes 4.35 million deaths per year in Europe (49% of all deaths) and costs the EU an estimated €169 billion per year. Hypertension, which is defined as blood pressure (BP) above 140/90mmHg, is one of the most common treatable risk factors for cardiovascular disease. Almost half of all European adults aged 35–64 years have hypertension. Although it is well established that antihypertensive therapy can reduce the risk of cardiovascular disease, rates of BP control remain low. Current European guidelines set a BP target of less than 140/90mmHg, which is often not achieved. The high frequency of uncontrolled hypertension was shown in the WHO MONICA Project, which evaluated the prevalence and control of hypertension in two independent cross-sectional surveys conducted in the 1980s and 1990s. These surveys showed that among hypertensive people aged 35–64 years, only 13–38% of men and 17–54% of women were receiving BP-lowering treatment. Recent data suggest that no more than 10% of treated patients achieve BP targets in many European countries. Inadequate control of BP exposes patients to a high risk of long-term cardiovascular complications, such as myocardial infarction, heart failure, stroke, renal disease and premature mortality. For individuals aged 40–69 years, the risk of cardiovascular disease-related mortality doubles with each 20mmHg increment in systolic BP or 10mmHg increase in diastolic BP over a BP range of 115/75–185/115mmHg. Poor control of hypertension can be attributed to several factors. These include patient-related factors, such as lack of awareness of hypertension; environmental factors, such as smoking or sedentary lifestyle; and physician-related factors, such as inadequately aggressive treatment.
Large-scale surveys conducted as part of the WHO MONICA Project showed that the percentage of individuals who were aware of their hypertension across Europe ranged from 30 to 62%. Although rates of awareness and treatment of hypertension increased during the 10-year study period, BP control remained far from adequate. Numerous environmental factors such as smoking, alcohol consumption, caloric intake, salt and potassium intake and lack of physical activity can adversely affect BP control. Although comprehensive lifestyle modification has been shown to improve BP control, such interventions are generally ineffective and compliance with these non-pharmacological measures is generally poor. Studies of the behaviour of physicians have shown that they frequently fail to increase the dose of antihypertensive medications or to try new treatments in patients with elevated BP.
Poor compliance with therapy is a major problem among patients with hypertension and is one of the main causes of failure to adequately control BP. While many factors contribute to poor compliance, such as a patient’s knowledge, attitudes and beliefs, or medication cost, it is the complexity of the dosing regimen and drug-related side effects that most likely play the largest roles in medication compliance. Current European treatment guidelines recommend that in all patients with hypertension, BP should be reduced to below 140/90mmHg, with a more stringent target of 130/80mmHg in patients with additional risk factors (e.g. diabetes or renal disease). The European Society of Hypertension (ESH)-European Society of Cardiology (ESC) 2007 Hypertension Guidelines recommend initiating antihypertensive therapy based not only on BP, but also on the total level of cardiovascular risk, including people with high to normal BP (130–139/85–89mmHg) and additional risk factors. For most patients, two or more antihypertensive drugs would be needed to achieve BP control.
While here I have focused upon hypertension, the challenges confronting the field of cardiology are diverse and manifold and thus it is imperative that we stay abreast of opinion and developments across the entire discipline. Through this collection of informative articles, European Cardiovascular Disease 2007 may assist us in achieving this goal.