Early morning blood pressure surge

Abstract

Alterations in the circadian rhythm of blood pressure, whether a loss of the nighttime dip or an exaggeration of the early morning increase that occurs upon rising, indicate increased cardiovascular risk. Estimates of the magnitude of the blood pressure surge on rising vary depending on technique and population, but it is usually around 10-30 mm Hg systolic and 7-23 mm Hg diastolic. The magnitude of the surge increases with age, alcohol consumption, and smoking and is greater in whites. Blood pressure variations and morning plasma aldosterone are closely correlated. A high morning surge is linked to increased target organ damage as well as strokes and other cardiovascular complications. Therapeutic options exist to reduce the magnitude of the morning blood pressure surge-notably, the use of drugs with a long duration of action, the use of medications that specifically antagonize the morning surge (such as alpha blockers), and the administration of drugs upon awakening but before rising.

Figure 1

Distribution of the systolic blood pressure (SBP) surge on rising in a population of 507 untreated hypertensive subjects. Data derived from J Hypertens. 2004;22:1113–1118. ¹³

Figure 3

Diagrammatic representation of the modes of blood pressure surge over 24 hours