Prognostic Value of Blood Pressure Variability and Average Blood Pressure Levels in Patients With Hypertension and Diabetes

Abstract

Elevated blood pressure (BP) is a major risk factor for cardiovascular (CV) events and mortality (1) and a leading contributor to the global disease burden (2). Overwhelming evidence is now available showing that BP measured in the office shows a linear relationship with a number of CV and renal outcomes as well as with overall mortality and that lowering of office BP (OBP) with treatment is effective in reducing morbidity and mortality (3,4). However, application over the last 40 years of techniques for out-of-office BP monitoring including home BP monitoring (HBPM) and 24-h ambulatory BP monitoring (ABPM) has led to further important findings. In particular, 1 ) average BP measured in everyday life conditions may be an even better predictor of CV outcomes than isolated OBP readings and 2 ) the extent of fluctuations of BP over time may provide additional, independent prognostic information compared with both isolated office readings and average ambulatory BP (ABP) levels, respectively. These findings are of upmost relevance in the case of diabetic patients who are characterized by a significantly higher risk of CV events compared with nondiabetic individuals, with diabetes itself currently considered a CV disease equivalent (5,6). The aim of the present article is to review the available evidence on the prognostic importance of BP mean levels and of BP variability (BPV) estimates and to critically evaluate whether antihypertensive treatment strategies should be targeted at reducing not only average BP levels but also the degree of BPV in order to optimize CV protection in diabetic patients. ### Prognostic value of OBP values Consistent evidence from observational studies has indicated that the risk of CV morbidity and mortality has a strong and continuous relationship with OBP levels (3), without any evidence of a threshold down to at least 115/75 mmHg (4). Furthermore, large meta-analyses of major interventional trials …