Kinetics of orthostatic blood pressure in primary hypertension.

Background: Primary Hypertension (HT) is the most prevalent cardiovascular disorder worldwide and is accompanied by significant morbidity and mortality.

Objectives: The present study aimed to investigate the kinetics of orthostatic Blood Pressure (BP) in primary hypertensive patients during the change from supine position to standing position as well as during the standing position using the Orthostatic Test (OT).

Patients and methods: This prospective study included a group of 107 primary hypertensive patients (mean age: 55.82 ± 11.35 years, ranging from 39 to 80 years). Orthostatic systolic BP (Ortho SBP) was recorded for 10 minutes at the rhythm of 3 measurements per minute and was compared to the values of supine systolic preorthostatic (Preortho SBP). According to the changes in Ortho SBP, three subgroups of primary hypertensive patients were selected as follows: Subgroup A: Ortho SBP was higher than mean Preortho SBP by 10 mmHg or more. Subgroup B: Ortho SBP was lower than mean Preortho SBP by 20 mmHg or more. Subgroup C: -20 mmHg < (Ortho SBP - Preortho SBP) < + 10 mmHg. The kinetics of each group was then recorded.

Results: In this study, the prevalence of subgroups A, B, and C was 27.1%, 15.9%, and 57.0%, respectively. In subgroup A, the adrenergic peripheral sympathetic alpha response was 20% during the OT.

Conclusions: Hypertensives with very similar supine SBP behavior could exhibit widely different Ortho SBP. Thus, careful and effective treatment of hypertensives requires careful consideration and assessment of orthostatic BP.