When should antihypertensive drug treatment be initiated and to what levels should systolic blood pressure be lowered? A critical reappraisal.

The evidence for two recommendations of all major guidelines on hypertension is critically discussed. The first recommendation is that of initiating antihypertensive drug treatment when systolic blood pressure is at least 140 or diastolic blood pressure at least 90 mmHg in patients with grade 1 hypertension and low or moderate total cardiovascular risk, and even when blood pressure is in the high normal range in patients with diabetes and previous cardiovascular disease. The second recommendation is that of achieving systolic blood pressure levels below 140 mmHg in all hypertensive patients, including the elderly, and values below 130 mmHg in patients having diabetes and high/very-high-risk patients. Critical analyses of the results of available trials show that the evidence is scanty for both recommendations. Nonetheless, they can be accepted as prudent statements, as antihypertensive agents are very well tolerated and lowering systolic blood pressure below 130 mmHg appears well tolerated. However, wisdom should not be taken for evidence, and simple trials should be designed to look for more solid evidence in favour of current recommendations.