Vania Zaetta

Prevalence and Clinical Significance of Isolated Ambulatory Hypertension in Young Subjects Screened for Stage 1 Hypertension

Little is known about the clinical significance of isolated ambulatory hypertension, a condition characterized by low office but elevated ambulatory blood pressure. This study aimed to investigate the prevalence and the predictive value of isolated ambulatory hypertension diagnosed after 3 months of observation for the development of sustained hypertension within a cohort of 871 never-treated stage-1 hypertensive subjects. The study end point was progression to more severe hypertension and need of antihypertensive medication. In 244 subjects (28%), clinic blood pressure declined to <140/90 mm Hg after 3 months. Of these, 124 (14.2% of total) had low clinic and ambulatory blood pressures after 3 months (nonhypertensive subjects), whereas 120 subjects (13.8% of total) showed low clinic but elevated ambulatory blood pressure (isolated ambulatory hypertension). During the 6 years of observation, the number of end points based on multiple clinic blood pressure readings progressively increased from the nonhypertensive subjects (19%) to the subjects with isolated ambulatory hypertension (35%) and to the subjects with high clinic and high ambulatory blood pressures (65%, P <0.0001). In an adjusted proportional hazard model, isolated ambulatory hypertension status was associated with a 2.2 (P <0.02) increase in the risk of reaching the end point in comparison with the nonhypertensive subjects. Final ambulatory systolic blood pressure was also higher in the former than the latter (P =0.03). Our results indicate that among subjects screened for stage 1 hypertension, individuals with isolated ambulatory hypertension after 3 months of observation have increased risk of developing sustained hypertension in later life compared with subjects in whom both clinic and ambulatory blood pressures are normal.

Evolution of blood pressure and cholesterol in stage 1 hypertension: role of autonomic nervous system activity

Objective Controversy remains concerning the pathogenetic mechanisms for the relationship between sympathetic activity, hypertension and lipid abnormalities. We tested the hypothesis that a condition characterized by sympathetic predominance may affect the evolution of blood pressure and lipids in the early stage of hypertension. Methods We prospectively studied 163 young stage 1 hypertensive individuals and 28 normotensive control individuals. The hypertensive subjects were divided by cluster analysis into two groups according to low frequency and high frequency components of heart rate variability. Large artery and small artery compliance was assessed at the end of the follow-up. Results Fifty-nine subjects showed reduced total power and signs of sympathetic predominance in the resting condition, on standing and during mental stress (group 1). At baseline, they had similar blood pressure and metabolic data to the rest of the group (n = 104, group 2) and a greater white-coat effect (P = 0.03). During a 6-year follow-up, 23.7% of group 1 subjects versus 9.6% of group 2 subjects developed sustained hypertension requiring antihypertensive treatment (P = 0.02). In group 1 subjects, there was also a greater increase in total cholesterol (P = 0.01) than in group 2. In addition, at the end of follow-up group 1 subjects had impaired large artery compliance (P < 0.001 versus group 2). Conclusions These data indicate that a condition characterized by sympathetic predominance may favour the development of sustained hypertension and hypercholesterolemia early in life, and lead to increased susceptibility to vascular complications. They further indicate that the increased white-coat effect is not an innocent phenomenon.

Validation of the SAA-102 home blood pressure monitor according to the protocols of the European Society of Hypertension, the Association for the Advancement of Medical Instrumentation and the British Society of Hypertension.

ObjectiveTo determine the accuracy of a new oscillometric home blood pressure (BP) monitor for arm BP measurement, the SAA-102, developed by the Sensacare Company. DesignEvaluation of the SAA-102 was performed using validation protocols of the European Society of Hypertension (ESH), the Association for the Advancement of Medical Instrumentation (AAMI), and the British Hypertension Society (BHS). MethodsThe SAA-102 monitor was assessed on 33 participants according to ESH requirements, which are based on four zones of accuracy differing from the mercury standard by 5, 10, 15 mmHg or more. Then the oscillometric monitor was tested on 85 participants according to AAMI criteria which require a mean device–observers discrepancy within 5±8 mmHg. Finally, the electronic device was evaluated on 93 participants according to BHS requirements, which are based on five phases: before-use calibration, in-use assessment, after-use calibration, static device validation and report of the results. ResultsThe SAA-102 passed all phases of the ESH international protocol for both systolic and diastolic blood pressure (SBP and DBP). The SAA-102 passed also AAMI criteria for SBP and DBP. The mean discrepancy between the SAA-102 and observers was 0.1±4.6 and −2.7±5.2 mmHg, for SBP and DBP, respectively. According to BHS protocol, the oscillometric monitor achieved final grading of A/A for SBP and DBP, respectively. ConclusionThese data show that the SAA-102 device satisfies ESH, AAMI, and BHS protocols for both SBP and DBP and may be recommended for everyday use for BP monitoring at home and in clinical practice.

Validation of the SAW-102 wrist home blood pressure monitor according to the protocols of the British Hypertension Society, the Association for the Advancement of Medical Instrumentation, and the European Society of Hypertension.

ObjectiveTo determine the accuracy of the SAW-102 wrist oscillometric blood pressure monitor developed by the Sensacare Company according to the protocols of the European Society of Hypertension (ESH), the Association for the Advancement of Medical Instrumentation (AAMI), and the British Hypertension Society (BHS). MethodsSAW-102 was assessed on 33 participants according to ESH requirements, based on four zones of accuracy differing from the mercury standard by 5, 10, 15 mmHg or more. Then SAW-102 was tested on 85 participants according to AAMI criteria requiring mean device–observers discrepancy within 5±8 mmHg. Subsequently, SAW-102 was evaluated on 88 participants according to BHS requirements. Finally, 15 participants with wrist circumference greater than the manufacturers recommendation (19.5 cm) were studied (large wrist group). Efforts were made to secure a stable position of wrist and arm at the heart level. ResultsSAW-102 passed all phases of ESH international protocol for both systolic blood pressure (SBP) and diastolic blood pressure (DBP). SAW-102 passed AAMI criteria with mean differences between SAW-102 and observers of 3.8±7.5 and 1.5±6.0 mmHg, SBP and DPB, respectively. According to BHS protocol, the device achieved final grading of B/B for SBP and DBP, respectively. Large wrist group did not pass the first phase of ESH protocol. ConclusionThis study demonstrated that SAW-102 meets the BHS, ESH, and AAMI standards when measurements are done at the heart level and when the manufacturers specifications, regarding wrist circumference, are respected. Our data also indicate that exceeding 19.5 cm wrist circumference is accompanied by dramatic decrease of the accuracy of the device.