Detection of non-dipper hypertensives in clinical practice: does it really matter?

Sir, In their recent Editorial Comment on night-time blood pressure (BP) in diabetic patients, Schernthaner et al. [1] argue that `ambulatory BP measurement is indispensable for optimizing antihypertensive treatment in diabetic patients with nephropathy' and that `the evaluation of night-time BP permits a much more focused antihypertensive treatment' in these patients. We feel that at present there is absolutely no evidence to support the usefulness of the assessment of the diurnal BP profile in the management of any subgroup of hypertensive patients, and more importantly, there are several good reasons to avoid it in general practice. First, there are several difficulties in the correct classification of hypertensive individuals as dippers and non-dippers. In the analysis of ambulatory BP data, fixed day and night periods are routinely applied, while actual patient reported sleeping hours are used only occasionally [2–4]. It has been shown however, that analysis of ambulatory BP profiles using arbitrary day–night-time schedules underestimate the nocturnal BP drop, resulting thereby in an overestimation of the prevalence of non-dippers [3,4]. Until ambulatory equipment manufacturers improve application software to allow for individualized analysis of ambulatory BP profiles, the interpretation of ambulatory BP data using individual patients reported sleeping hours is not feasible because it requires additional effort and time [4].