Background: Blood pressure (BP) has a circadian rhythm. Most of the people presents a BP fall between 10-20% during nighttime hours (dipper condition). Measurement of these circadian variations is performed by continuous blood pressure ambulatory monitoring. We have studied the possible relation between blood pressure nocturnal fall and cardiovascular risk factors in hypertensive patients.
Methods: We selected 100 hypertensive patients from the Hypertension and Lipids Unit of San Cecilio University Hospital of Granada, Spain. They were divided into two groups: dippers group and non-dippers, depending of whether or not the fall of nocturnal systolic and diastolic BP was > 10%. All patients included in the study underwent complete clinical history, exhaustive physical examination, complementary examinations, urine and hematology tests, and continuous blood pressure ambulatory monitoring by the Space Labs system.
Results: The heart rate was found to be significantly higher (p = 0.0253) in the hypertensive dippers group than in the non-dippers. The latter showed higher plasma creatinine values (p = 0.0343) and lower potassemia values (p = 0.0140) than the dippers group. The dippers group presented concentrations of HDL-cholesterol significantly higher (p = 0.008) and diurnal diastolic BP values (p = 0.0211) also higher than the other group.
Conclusions: Non dippers hypertensive patients present a higher number of cardiovascular risk factors as well as a higher tendency to renal lesions, and worse prognosis than the dippers group.