Areas of agreement Among the many guidelines and recommendations put forward by national and international authorities in recent years, there has been close agreement that the physician should assess each patient carefully over many months, should address the total profile of cardiovascular risk not just the raised blood pressure, and should treat patients right up to the age of 85 years with either classical essential hypertension or isolated systolic hypertension. The major guidelines described five groups of first-line antihypertensive drugs: diuretics,β-blockers; angiotensin converting enzyme (ACE) inhibitors, calcium antagonists and α-blockers.
Areas of uncertainty In other areas, the various guidelines were either united in uncertainty, or divided on the best course of action. The availability of many new methods and approaches for the measurement of blood pressure has introduced greater uncertainty into the interpretation of the blood pressure level in the individual patient, with question marks still surrounding the interpretation of white-coat hypertension, of ambulatory blood pressure monitoring and of home blood pressure readings in relation to clinic blood pressure. There is lack of uniformity in recommendations for the threshold values at which raised blood pressure should be lowered and in the recommendations for the target blood pressure the physician should set in the individual patient.
Choice of drug to initiate treatment Since the publication of the major guidelines in 1993 and 1994, the greatest uncertainty has surrounded the choice of drugs to initiate treatment. This reflects the fact that so far no major trials have been completed confirming that the newer agents such as ACE inhibitors, calcium antagonists or oc-blockers reduce cardiovascular morbidity and mortality in hypertensive patients. While awaiting the results of the many prospective randomized trials that are in progress with these newer agents, a number of case-control studies have raised concerns that non-potassium-sparing diuretics may increase the incidence of sudden cardiac death and that calcium antagonists might increase the occurrence of coronary heart disease in hypertensive subjects.
Current action These issues highlight the importance of initiating prospective, randomized, controlled trials early in the development of all new drugs. While awaiting the results of trials currently in progress, the physician should continue to use all five groups of antihypertensive drugs, tailoring the choice of drug to suit the individual patient, and should use low doses of antihypertensive drugs either alone, or in appropriate combinations.