The consistency of antihypertensive treatment over a 24-h period is reflected by the trough:peak ratio and smoothness index, derived from 24-h ABPM data. Trough:peak ratios are highly variable within any individual and are thus not a reliable clinical measure. Conversely, Foretinib ic50 the smoothness index reflects the size of BP reduction with treatment
and homogeneity throughout the 24-h period (higher values signifying antihypertensive treatments with a large and consistent effect). A higher smoothness index (lower BP variability) is associated with improved CV outcomes and reduced organ damage . Classification of daytime and night-time periods may be best done using information from patient diaries on their sleep patterns; however, fixed time periods representing
day (09:00–21:00) and night (01:00–06:00) are common, eliminating much of the inter- and intra-patient variability, but sacrificing early-phase night sleep BP dipping and early morning surge information, which have significance for CV outcomes. Different BP sampling intervals can be employed; however, it is recommended not to exceed 30 min between readings, to avoid incorrect estimation of mean values . It is recommended to repeat ABPM measurement Selleckchem Salubrinal if <70 % of the expected measurements within 24 h are recorded, including 20 valid awake and seven valid sleep measurements . ABPM readings are usually performed on the non-dominant arm (to reduce disruption to everyday activities), but there is currently a lack of consensus regarding the most suitable arm position for the patient to adopt during second measurements, with implications for data accuracy . ABPM and
HBPM may have greater prognostic value for risk of CV events than office measurements [2, 63, 64] and ABPM is associated with a doubling of BP control rates vs. office measurements . Central BP measurement has also been noted as an independent predictor of CV events in various populations; however, its relative value vs. brachial measurements is still under debate  and the benefit of achieving central BP reduction through antihypertensive treatment for patient outcomes has been investigated [Nifedipine GITS’s Effect on Central Pressure Assessed by Applanation Tonometry (FOCUS) study, NCT01071122]. Therapeutic decisions based on ABPM are superior to those based on office measurements ; for instance, the Valsartan in Systolic Hypertension (Val-Syst) trial demonstrated that the treatment-induced reduction in clinic SBP was considerably greater than the mean 24-h BP reduction, measured by ABPM (31.9 vs. 13.4 mmHg, respectively), which was attributable to a white coat effect . Furthermore, in patients with white coat hypertension, no change was seen in 24-h BP or that in the hour following treatment, Ro 61-8048 datasheet whereas a large decrease in SBP was seen . Had ABPM not been used, this apparent BP-lowering effect would have been wrongly attributed to treatment.