Current Hypertension Reports

The publication of the Antihypertensive and Lipid-lowering Treatment to Prevent Heart Attack Trial (ALLHAT) results, when used in conjunction with a new meta-analysis, provides hypertension research with a watershed. Data demonstrate clearly that lowering blood pressure is the most important aspect of hypertension management, and that all agents are similarly effective. There is little sustainable evidence for pressure-independent advantages for any class of drug at this time. Therefore, by combining these findings with additional information on target levels of blood pressure and safety, plus the use of aspirin and statins, we can formulate health care policies that attack hypertension in a holistic risk-based way. The future will focus on gaining extra benefit for patients by testing the efficacy and superiority of drug combinations using novel agents that favorably influence intermediate markers such as arterial stiffness, and arresting the ever-increasing burden of cognitive impairment and dementia.

Both hypertension and diabetes carry an increased risk of cardiovascular and renal disease and are commonly associated conditions. The prevalence of hypertension in the diabetic population is particularly high, approximately 40% in middle-aged patients with type II diabetes mellitus and increases to approximately 60% by age 75. Hypertension increases an already high risk of cardiovascular disease events associated with diabetes mellitus and is also a risk factor for the development of microalbuminuria and retinopathy. Overall mortality from heart disease has declined substantially in the USA in the past 30 years. The extent of this mortality rate decline has been assessed from representative cohorts [1], the NHANES I survey (1971–1975) and the NHANES I epidemiologic follow-up survey (1982–1984). Both cohorts were followed prospectively for 8 to 9 years. Mortality rates for heart disease and ischemic heart disease in men and women with diabetes have not decreased to the extent that they have for nondiabetic patients. Although these decreases in men with diabetes were smaller than their nondiabetic counterparts, women with diabetes had increases for both total and ischemic heart disease. Three recent clinical trials have addressed the effects of aggressive intervention in diabetes, particularly older patients with type II diabetes mellitus.

Much has been published about the impact of treatment on adverse outcomes in patients with cardiovascular diseases. Hypertension is an extremely common condition affecting a significant percentage of the world population. Although care guidelines exist for the medical patient with raised blood pressure, there are no accepted guidelines for the preoperative evaluation and perioperative care of the patient with hypertension who undergoes noncardiac surgery. Of particular importance are defining at-risk groups of patients, and the indications for cancellation to treat and hence reduce this risk. This review examines the interactions between hypertension, drug therapies, anesthesia, and adverse outcomes in these patients. Recommendations for identifying patients at greatest risk of adverse cardiovascular events and cardiac mortality have been developed through evaluation of available data. Based on these findings, the only patients in whom cancellation may be justified and the level of hypertension treated prior to surgery are those with stage 2 hypertension and accompanying target-organ damage, or stage 3 hypertension (blood pressure > 180/> 110 mm Hg).

Nonpharmacologic and pharmacologic treatment can significantly attenuate the symptoms of orthostatic hypotension. Some of the interventions that are used to treat orthostatic hypotension have been known for decades. However, several new treatment strategies have been developed in recent years. New knowledge about the pathophysiology of orthostatic syndromes has been gathered that will strongly influence the way treatments are tailored to individual patients. For example, patients with and without residual autonomic function exhibit differential responses to certain treatments. A large subgroup of patients with severe autonomic failure show a profound pressor response to water drinking. This simple effect can be exploited to treat orthostatic and postprandial hypotension in some patients. New bioengineering technologies that attempt to replicate normal baroreflex mechanisms may become available for selected patients with central autonomic dysfunction.

The objective of this study was to describe the increasing incidence and risk of cardiovascular disease among persons living with HIV (PLWH) in Sub-Saharan Africa. We also used data to compare hypertension (a common NCD among PLWH) outcomes between PLWH and HIV–uninfected individuals among older adults in Northwestern Tanzania. Hypertension is increasingly common in Sub-Saharan Africa and a leading cause of cardiovascular disease for PLWH. Among those with hypertension, PLWH have a 50% higher risk of incident myocardial infarction compared to the general population. In response to the rising incidence of these non-communicable diseases (NCDs) among PLWH, recently, the Joint United Nations Program on HIV/AIDS supported the integration of NCD care into routine clinical care for HIV. However, data are lacking on levels of awareness of hypertension status, diagnosis, and antihypertensive medication adherence. Given the higher likelihood of elevated blood pressure among PLWH, there is an urgent need to implement interventions to improve blood pressure control in this population. Researchers should evaluate treatment barriers at multiple levels including health system, healthcare providers, and patients’ level and tailor evidence-based interventions to increase achievement of blood pressure control for PLWH.

Endothelin (ET)-1, a 21-amino acid peptide, is the predominant isoform of the endothelin peptide family. ET-1 is ubiquitously expressed and stimulates vasoconstriction and cell proliferation. Enzymes such as endothelin converting enzymes (ECE), chymases, and non-ECE metalloproteinases contribute to the synthesis of ET-1, which is regulated in an autocrine fashion in vascular and nonvascular cells. Endothelin ETA receptors mediate vasoconstriction and cell proliferation, whereas ETB receptors are involved in the clearance of ET-1, inhibition of endothelial apoptosis, release of nitric oxide and prostacyclin, and inhibition of ECE-1 expression. Most cardiovascular diseases, such as arterial hypertension, atherosclerosis, restenosis, heart failure, idiopathic cardiomyopathy, pulmonary hypertension, and renal failure are associated with local activation of the endothelin system. Experimental studies and first clinical trials suggest that ET-1 is importantly involved in the functional and structural changes in the cardiovascular system, and that many of the actions of ET-1 are mediated through pressure-independent mechanisms. Endothelin antagonists promise to be successful as a new class of drugs for the treatment of cardiovascular diseases.

Menopause is accompanied by a dramatic rise in the prevalence of hypertension in women, suggesting a protective role of endogenous estradiol on blood pressure (BP). Both animal experimental and human clinical investigations suggest that estrogen engages several mechanisms that protect against hypertension, such as activation of the vasodilator pathway mediated by nitric oxide and prostacyclin and inhibition of the vasoconstrictor pathway mediated by the sympathetic nervous system and angiotensin. However, emerging evidence from recent clinical trials indicates a small increase, rather than decrease, in systolic BP with oral estrogen administration in postmenopausal women, without any detectable effect on diastolic BP. Mechanisms underlying this selective rise in systolic BP in postmenopausal women and oral contraceptive-induced hypertension in premenopausal women remain unknown, but the rise may be related to supraphysiologic concentration of estrogen in the liver. To date, transdermal delivery of estrogen, which avoids the first-pass hepatic metabolism of estradiol, appears to have a small BP-lowering effect in postmenopausal women and may be a safer alternative in hypertensive women.