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Background Pathogenesis of primary hypertension remains unclear, because many heterogeneous factors (diet, physiologic, and psychological factors) are simultaneously involved. We have conducted an original analysis to study the influence of the combination of these factors on BP evolution. Methods Seven homogeneous clusters were constituted from 213 healthy normotensive subjects taking into account 10 variables. Those variables used to cluster homogeneous “risk profiles” are usually considered as potential risk factors for hypertension: age, body mass index, alcohol consumption, sodium/potassium urinary ratio, systolic blood pressure (SBP) and heart rate response to mental stress, baroreflex sensitivity (BRS), job demand, job latitude, and behavioral pattern (personality score). Five-year BP evolution (ΔSBP or Δdiastolic BP [DBP]) was compared between risk profiles. Results Four clusters of subjects representing about 50% of the population had a significantly higher 5-year ΔSBP (≥5 mm Hg) compared to the 5-year ΔSBP of the two clusters in which SBP did not increase. These four clusters had a low BRS. Two profiles that group six unfavorable risk factors had the most detrimental 5-year ΔSBP. Interestingly, perceived high job demand in a cluster of younger subjects with a high personality score and a low BRS had also a detrimental SBP evolution. Conclusions The major interest of this study is to highlight that hypertension development is not univocal between subjects and that different combinations of factors could explain differential BP evolution in groups of subjects sharing the same risk profile. A lower BRS was a consistent predictor for detrimental 5-year BP evolution.

Background The aim of this analysis was to test, in a large sample of normotensive subjects, the short-term influence of job strain on the onset of hypertension. Methods According to the questionnaire of Karasek et al, job strain was divided into four modalities: (high strain, low strain, passive, and active) based on job demand (eg, the need to work hard and quickly) and job latitude (eg, control over skill use, time allocation, and organizational decisions) scores. High strain (HS) was defined by a high demand and a low job decision latitude. Individual data obtained in 926 (age 41 ± 6 years) healthy normotensive or newly diagnosed hypertensive subjects were analyzed. Subjects participated in two prospective work site surveys designed to assess the influence of job strain on hypertension development. Relationships between job strain modalities and work site blood pressure (BP) levels were assessed using a general linear model. A complementary analysis using the the Pearson Φ coefficient (Z analysis) was implemented to explore nonlinear or scattered relationships between job strain and onset of hypertension. Results Systolic BP (SBP) was linearly related significantly to BMI and alcohol consumption, whereas diastolic BP (DBP) was related to age. The linear model did not find any relationship between SBP or DBP and job strain modalities. Using the Z analysis, development of systolic hypertension (SBP >140 mm Hg) was significantly associated with high job strain ( P Conclusions Our results suggest that there is no global relationship between job strain and BP levels. However our methodology revealed a significant association between job strain and work site BP in a predominantly male subgroup of newly diagnosed hypertensive subjects exposed to high job strain.

Scarce information is available on stress-induced renal behavior in humans, especially in normotensives offspring of hypertensives (HP) and in hypertensives (HT).Ten HP and 10 HT were compared to 10 normotensives with normotensive parents (NP). Systolic blood pressure (SBP) and renal functional parameters were determined during rest and stress periods.The stress SBP reactivity was significantly (P.05) higher in HP than in NP and HT. At rest, HP were characterized by a significantly (P.05) higher glomerular filtration rate. Stress significantly reduced glomerular filtration rate (-14 +/- 4 mL/min/1.73 m2, P.05) only in HT. Renal plasma flow significantly (P.05) decreased during stress in NP (-35 +/- 16 mL/min/1.73 m2) and in HT (-49 +/- 25 mL/min/1.73 m2), whereas it did not change in HP. The resulting filtration fraction increased significantly during stress only in NP (1.5% +/- 0.6%, P.05). Despite the increase in BP, stress induced a similar decrease in sodium excretion rate in NP (-52 +/- 26 micromol/min) and in HT (-56 +/- 24 micromol/min). The stress-induced sodium reabsorption occurred only in the proximal part of the tubules (lithium clearance). In HP, stress did not alter either sodium excretion rate or plasma renin activity.The stress-induced renal modifications are characterized by an efferent vasoconstriction and a paradoxical increase in sodium reabsorption that occurred in the proximal part of the tubules in NP. In HP, genetically at risk of hypertension, basal renal alterations may explain a different stress-induced renal behavior. In HT, stress-induced increase in sodium reabsorption may be involved in the sustained BP level.

This study was performed to assess changes in renal function accompanying cardiovascular responses to mental stress. Glomerular filtration rate (GFR, inulin clearance), renal plasma flow (RPF, PAH clearance), filtration fraction (FF), sodium excretion, and segmental sodium tubular reabsorption (lithium clearance) were measured in 15 normal volunteers during rest and stress. The psychological stress test used is based on a computerized version of the Stroop word color conflict test. Stress induced a significant (P less than .05) and sustained increase in blood pressure and heart rate. During stress, GFR and RPF did not change whereas FF increased significantly (P less than .05) and sodium excretion tended to decrease. The decrease in sodium excretion was due to a significant (P less than .05) increase in proximal reabsorption, which may be mediated by renal hemodynamic changes. The observed significant increase in FF suggests an increase in postglomerular arteriolar resistances, which may account for the increase in proximal sodium reabsorption through an alteration in peritubular Starling forces. In the long run, the stress-associated increase in sodium reabsorption may contribute to the development of hypertension.

BACKGROUND The main factors studied possibly explaining inadequate blood pressure (BP) control in the population are related either to treatment or to patients. Subjective behavior of physicians might also explain insufficient BP control in the population. This study analyzed the consistency between systolic BP (SBP) targets set by physicians for uncontrolled hypertensive patients and the guidelines according to cardiovascular (CV) risk factors. METHODS A total of 993 general practitioners completed 2,455 questionnaires which included items related to the clinical and biological characteristics of uncontrolled hypertensive patients. At the end of each questionnaire, physicians noted the SBP level they targeted for each patient. The coronary heart disease (CHD) risk score was computed for each patient according to the Framingham study. RESULTS The mean SBP target set by physicians was 136 +/- 6 mm Hg. However, in 24% of the patients, SBP targets set by physicians were higher than those recommended and, above all, the higher the Framingham CHD risk score, the lower the percentage of subjects with correctly targeted SBP goals. SBP values targeted by physicians were higher than recommended goals mostly in patients with diabetes and/or renal impairment. Interestingly, the targeted SBP was significantly and positively correlated with the previously determined office SBP (r = 0.26, P < 0.001). CONCLUSIONS The higher the CV risk, the lower the number of patients with targeted SBP in accordance with guidelines. When considering CV risk factors, physicians did not take into account that a lower BP goal is advocated for patients with diabetes and renal impairment.