Controlling resistant hypertension

Figure 1. Prevalence, awareness, treatment and control of hypertension in China. Data are shown stratified by age and sex. (Reproduced with permission from Elsevier: Lu et al. 5)

Figure 2. The combined effects of low sodium and the DASH diet according to baseline blood pressure. The mean end of period SBP measurements (mm Hg) by strata of (A) baseline SBP (<130, 130–139, 140–149, >150 mm Hg) or (B) baseline DBP (<80, 80–84, 85–89, >90 mm Hg). The mean blood pressure values are presented by the high-sodium control diet (circle) or the low-sodium DASH diet (diamond). Differences between diets were determined using linear regression comparing baseline changes in systolic or diastolic blood pressure adjusted for age, female sex, black race and baseline body mass index. Bars indicate 95% CIs. Ctrl, control; DASH, Dietary Approaches to Stop Hypertension trial; DBP, diastolic blood pressure; NA, sodium; SBP, systolic blood pressure. (Reproduced with permission from Elsevier: Juraschek et al.11)

Figure 3. The physiology of therapy for resistant hypertension. When the kidney senses low blood pressure, renin is released, leading to production of angiotensin II. In turn, angiotensin II activates production of aldosterone by the adrenal cortex, which leads to salt and water retention. Under healthy conditions, this system is turned off once normal body water levels are restored. Impairment of this system can cause hypertension. Renal hypertension is associated with high renin and secondary hyperaldosteronism; in primary hyperaldosteronism the salt and water retention suppresses renin production, so aldosterone levels are high with low renin levels. Abnormalities of the renal tubular epithelial sodium channel cause salt and water retention, suppressing both renin and aldosterone. To identify the best primary therapy for patients with resistant hypertension, the physiological mechanism underlying the blood pressure elevation must be identified (table 1). (Reproduced with permission from Nature: Spence29).