Statement on ambulatory blood pressure monitoring by the German Hypertension League. Blood pressure measurement section of the Deutsche Liga zur Bekämpfung des hohen Blutdruckes e.V. (German Hypertension League).

Blood pressure (BP) variation is particularly pronounced in those who suffer from hypertension. Single measurements should therefore be regarded as no more than 'snapshots' out of a large number of BP values occurring during the course of a day. Indirect ambulatory blood pressure monitoring (ABPM), a method which is becoming increasingly common, provides the best information on daily BP using automatic measuring and recording equipment. This results in improved diagnosis, better treatment indications and better evaluation of the outcome of treatment and of prognosis. Compared with ABPM occasional BP measurement by the GP overestimates the diagnosis of hypertension and underestimates the antihypertensive effect of drugs. ABPM allows the following to be picked up: average BP level; circadian BP rhythm; increases in BP which occur only at the doctor's office (white coat hypertension); absence of, or reduced, fall in BP during sleep; unusual rises or falls in BP; side-effects of anti-hypertensive treatment thought to be dependent on the BP level. ABPM is especially suitable for evaluating the success of treatment and provides real information on the effectiveness of medication. ABPM has a closer correlation with left ventricular hypertrophy and with other cardiovascular complications than do BP measurements by the GP. There is now a sufficient body of evidence available to support the observation that there is a higher rate of organ damage in cases where no night-time fall in BP occurs than might be expected from the average daily values. The acceptance of ABPM can now be termed good to very good.