Superiority of 24-hour Measurement of Blood Pressure Over Clinic Values in Determining Prognosis in Hypertension

Abstract

Long-term recordings of blood pressure in an individual could logically be expected to have greater prognostic power than values recorded in the clinic in view of the known inaccuracies and variability of the latter. This feature has been shown to be true in a large series investigated by Perloff and colleagues¹. Specific components of the 24h profile may have greater prognostic power than others, ‘basal’ blood pressure (generally equated with night-time resting values) has been thought by some² to have greater predictive value than that recorded during less standardised activity at other times of day. A further hypothesis is that high intrinsic blood pressure variability may play an independent role in determining cardiovascular pathology when measured either as a global index³ or as a specific component such as the slope of the early morning rise in pressure⁴.