Circadian Pattern of Ambulatory Blood Pressure in Hypertensive Patients With and Without Type 2 Diabetes

Abstract

There is strong association between diabetes and increased risk of end-organ damage, stroke, and cardiovascular disease (CVD) morbidity and mortality. Non-dipping (p < .001), mainly during the hours of nighttime sleep and initial hours after morning awakening, independent of presence/absence of BP-lowering treatment. Ambulatory DBP, however, was significantly higher (p < .001) in patients without diabetes, mainly during the daytime. Differing trends for SBP and DBP between groups resulted in large differences in ambulatory pulse pressure (PP), it being significantly greater (p < .001) throughout the entire 24 h in patients with diabetes, even after correcting for age. Prevalence of non-dipping was significantly higher in patients with than without diabetes (62.1% vs. 45.9%; p < .001). Largest difference between groups was in the prevalence of the riser BP pattern, i.e., asleep SBP mean greater than awake SBP mean (19.9% vs. 8.1% in patients with and without diabetes, respectively; p < .001). Elevated asleep SBP mean was the major basis for the diagnosis of hypertension and/or inadequate BP control among patients with diabetes; thus, among the uncontrolled hypertensive patients with diabetes, 89.2% had nocturnal hypertension. Our findings document significantly elevated prevalence of a blunted nocturnal BP decline in hypertensive patients with diabetes. Most important, prevalence of the riser BP pattern, associated with highest CVD risk among all possible BP patterns, was more than twice as prevalent in diabetes. Patients with diabetes also presented significantly elevated ambulatory PP, reflecting increased arterial stiffness and enhanced CVD risk. These collective findings indicate that diabetes should be included among the clinical conditions for which ABPM is recommended for proper CVD risk assessment. (Author correspondence: rhermida@uvigo. es )