Differences in circadian time structure of diastolic blood pressure between diabetes mellitus and essential hypertension

Abstract

BackgroundAbnormal circadian blood pressure patterns have been associated with cardiovascular disease in diabetes mellitus. We have described that the acrophase of diastolic blood pressure (DBP) registered in type 1 diabetes (T1D) patients was significantly earlier than normal and DBP ecphasia was more pronounced in patients with lower heart rate variability during deep breathing. The aim of this study was to compare the circadian rhythm characteristics of BP among different groups: normotensive (NT) control subjects, patients affected by T1D and type 2 diabetes (T2D), and patients with essential hypertension (HT).FindingsWe retrospectively evaluated ambulatory blood pressure monitoring records in 30 NT, 20 T1D, 20 T2D, 20 HT whose fasting plasma glucose and HbA1c were contemporaneously measured. The four groups were well-matched regarding age, gender, and BMI.Systolic blood pressure (SBP) and DBP midline-estimating statistic of rhythm were higher in T1D, T2D, and HT groups. DBP ecphasia was present only in the diabetic individuals: the acrophase of DBP occurred four hours earlier than normal in T1D group, whereas two hours earlier in T2D group. In a multiple regression analysis, only HbA1c and SBP acrophase were statistically significant correlates of DBP acrophase.ConclusionsPeople with diabetes mellitus, both type 1 and type 2, have their circadian acrophase of DBP occurring 2–4 hours earlier than normotensive and hypertensive subjects. Altered circadian timing of DBP, potential trigger of cardiovascular events, seems to be a distinguishing feature of diabetes mellitus and correlates with the previous 2–3 months of glycaemic control.

Ambulatory Blood Pressure Monitoring and Circadian Rhythm of Blood Pressure in Diabetes Mellitus

“…14 Recently, in order to compare the circadian rhythm characteristics of blood pressure among different groups, we have retrospectively evaluated ABPM records in normotensive control subjects, patients with type 1 and type 2 diabetes, and patients with essential hypertension who were well matched regarding age, gender, and body mass. 17 The MESOR of systolic and diastolic blood pressure was higher in patients with type 1 diabetes, type 2 diabetes, and essential hypertension. Diastolic blood pressure ecphasia was present only in the diabetic individuals: the acrophase of diastolic blood pressure occurred 4 hours earlier than normal in type 1 diabetes, whereas 2 hours earlier in type 2 diabetes.…”