Clinical presentation and management of patients with uncontrolled, severe hypertension: results from a public teaching hospital

Outcomes of minority patients with very severe hypertension (>220/>120 mmHg)

OBJECTIVES

Acute severe hypertension is a common problem among inner-city ethnic minority populations. Nevertheless, the effects of currently employed treatment regimens on blood pressure have not been determined in a clinical practice setting. We determined the SBP responses to acute antihypertensive drug protocols and the 2-year natural history of patients presenting with severe hypertension.

METHODS

Retrospective cohort investigation in consecutive patients with SBP at least 220 mmHg and/or DBP at least 120 mmHg during 3-month enrollment in 2014 with 2-year follow-up. Primary outcomes were SBP versus time for the first 5 h of emergency treatment and 2-year follow-up including repeat visits, target organ events, and hospitalizations.

RESULTS

One hundred and fifty-six unique patients met criteria with 69% Black; 34% Hispanic; 56% had previous visits for severe hypertension; 31% had preexisting target injury. Acute management: Acute antihypertensive regimens resulted in grossly unpredictable and often exaggerated effects on SBP. Treatment acutely reduced SBP to less than 140 mmHg in 30 of 159 patients. Clonidine reduced SBP to less than 140 mmHg in 19/61. Two-year follow-up: We observed 389 repeat visits for severe hypertension, 99 new target events, and 76 hospitalizations accounting for 620 hospital days.

CONCLUSION

Acute treatment of severe hypertension produced unpredictable and potentially dangerous responses in SBP. Two-year follow-up demonstrated extraordinary rates of recurrent visits, target organ events, and hospitalizations. Our findings indicate a need to develop effective management strategies to lower blood pressure safely and to prevent long-term consequences. Our findings may apply to other hospitals caring for ethnic minority populations.

Risk of Intracerebral Hemorrhage after Emergency Department Discharges for Hypertension

BACKGROUND

Recent literature suggests that acute rises in blood pressure may precede intracerebral hemorrhage. We therefore hypothesized that patients discharged from the emergency department with hypertension face an increased risk of intracerebral hemorrhage in subsequent weeks.

METHODS

Using administrative claims data from California, New York, and Florida, we identified all patients discharged from the emergency department from 2005 to 2011 with a primary diagnosis of hypertension (ICD-9-CM codes 401-405). We excluded patients if they were hospitalized from the emergency department or had prior histories of cerebrovascular disease at the index visit with hypertension. We used the Mantel-Haenszel estimator for matched data to compare each patient's odds of intracerebral hemorrhage during days 8-38 after emergency department discharge to the same patient's odds during days 373-403 after discharge. This cohort-crossover design with a 1-week washout period enabled individual patients to serve as their own controls, thereby minimizing confounding bias.

RESULTS

Among the 552,569 patients discharged from the emergency department with a primary diagnosis of hypertension, 93 (.017%) were diagnosed with intracerebral hemorrhage during days 8-38 after discharge compared to 70 (.013%) during days 373-403 (odds ratio 1.33, 95% confidence interval .96-1.84). The odds of intracerebral hemorrhage were increased in certain subgroups of patients (≥60 years of age and those with secondary discharge diagnoses besides hypertension), but absolute risks were low in all subgroups.

CONCLUSIONS

Patients with emergency department discharges for hypertension do not face a substantially increased short-term risk of intracerebral hemorrhage after discharge.

Management of Discharged Emergency Department Patients with a Primary Diagnosis of Hypertension: A Multicentre Study

Introduction Many patients are seen in the emergency department (ED) for hypertension, and the numbers will likely increase in the future. Given limited evidence to guide the management of such patients, the practice of one's peers provides a de facto standard.

METHODS

A survey was distributed to emergency physicians during academic rounds at three community and four tertiary EDs. The primary outcome measure was the proportion of participants who had a blood pressure (BP) threshold at which they would offer a new antihypertensive prescription to patients they were sending home from the ED. Secondary outcomes included patient- and provider-level factors associated with initiating an antihypertensive based on clinical vignettes of a 69-year-old man with two levels of hypertension (160/100 vs 200/110 mm Hg), as well as the recommended number of days after which to follow up with a primary care provider following ED discharge.

RESULTS

All 81 surveys were completed (100%). Half (51.9%; 95% CI 40.5-63.1) of participants indicated that they had a systolic BP threshold for initiating an antihypertensive, and 55.6% (95% CI 44.1-66.6) had a diastolic threshold: mean systolic threshold was 199 mm Hg (SD 19) while diastolic was 111 mm Hg (SD 8). A higher BP (OR 12.9; 95% CI 7.5-22.2) and more patient comorbidities (OR 3.0; 95% CI 2.1-4.3) were associated with offering an antihypertensive prescription, while physician years of practice, certification type, and hospital type were not. Participants recommended follow-up care within a median 7.0 and 3.0 days for the patient with lower and higher BP levels, respectively.

CONCLUSIONS

Half of surveyed emergency physicians report having a BP threshold to start an antihypertensive; BP levels and number of patient comorbidities were associated with a modification of the decision, while physician characteristics were not. Most physicians recommended follow-up care within seven days of ED discharge.

Management of hypertension in hospitalized patients

Elevated blood pressure (BP) is a common problem in patients hospitalized for reasons other than hypertension. Unexpected elevations commonly result in calls to physicians who too often prescribe medication to reduce the numbers without evaluating the patient or determining the cause of the elevation. This may result in unnecessary and sometimes harmful treatment. Such BP elevation has many potential causes. These include anxiety, post-operative salt and volume overload, failure to administer the patient's known antihypertensive medication, inability to give oral antihypertensive medication to patients who cannot take pills by mouth, incipient heart failure, previously unrecognized renal failure, obstructive uropathy and other causes. These must be identified and treated prior to addressing only the elevated BP numbers. We present an algorithm for evaluating hospitalized patients with elevated BP in order to assist physicians in identifying the true cause of the elevation, treating the identified cause, and giving appropriate drug treatment. We also note that this is a golden opportunity for communication with the outpatient providers who will follow the patient.

Emergency department patients with acute severe hypertension: a comparison of those admitted versus discharged in studying the treatment of acute hypertension registry

OBJECTIVES

To compare the characteristics, treatments, and outcomes for emergency department (ED) patients with severe hypertension by disposition (admitted versus discharged home).

METHODS

Studying the Treatment of Acute hyperTension (STAT) is a multicenter registry of 1566 patients with blood pressure ≥180/110 mm Hg who were treated with intravenous antihypertensive medications in an ED or intensive care unit. Presenting and in-hospital variables, and postdischarge outcomes for the 1053 patients in the ED subset were compared by disposition.

RESULTS

In the multivariable analysis, ED patients were less likely to be discharged if >75 years of age (odds ratio [OR] = 0.3, 95% confidence interval [CI] = 0.1-0.9) or if they had shortness of breath (OR = 0.4, 95% CI = 0.2-0.8) or alteration of mental status (OR = 0.1, 95% CI = 0.02-0.9) on arrival. Nondialysis patients with an admission creatinine concentration >1.5 mg/dL were 80% less likely to be discharged than those ≤1.5 mg/dL (OR = 0.2, 95% CI = 0.08-0.5). In the bivariate analysis, patients with a decrease in systolic blood pressure of <10% 2 hours after medication administration were more likely to be admitted than those discharged (57% vs. 44%; P = 0.041). Disposition did not correlate with 90-day or 6-month mortality or 30-day readmission. However, admitted patients had a higher 90-day readmission rate (38% vs. 24%; P = 0.038).

CONCLUSIONS

ED patients with severe hypertension were more likely to be admitted to the hospital if they were >75 years of age, presented with shortness of breath or altered mental status, or had a creatinine >1.5 mg/dL and were not on hemodialysis.

The management of severe hypertension in Australian general practice

BACKGROUND

Severe hypertension (SHT) (Blood Pressure, BP ≥ 180/110 mmHg) is associated with considerable morbidity and mortality, yet little is known about how it is managed. The purpose of this study is to examine the management of SHT by Australian general practitioners (GPs) and to explore its variance across patient characteristics and clinical practices.

METHODS

Review of electronic medical records for a year before and after a recorded measure of SHT in 7,499 patients by 436 GPs in 167 clinics throughout Australia during 2008-2009. Outcome measures included follow-up, referral, changes to antihypertensive drug treatment, and BP control (normotensive reading, BP < 140/90 mmHg, and whether subsequent recorded measures were also in the normal range--sustained normotension).

RESULTS

Of 7,499 patients with an electronic BP record of SHT, 94% were followed up (median time 14 days); 8% were referred to an appropriate specialist (median time 89 days--2% within 7 days) and 86% were managed by GPs. GPs initiated or changed antihypertensive drugs in 5,398 patients (72% of cohort); of these, 46% remained hypertensive (4% with SHT) and 7% achieved sustained normotension; 6% had no further electronic BP records. The remaining 14% had no medication changes; among these, 43% remained hypertensive (5% with SHT) and 3% achieved sustained normotension; 32% had no further electronic BP records. Some outcome measures displayed a variance across GP clinics that was mostly unexplained by patient or practice characteristics.

CONCLUSIONS

Most patients with SHT had at least one follow-up visit and 72% had initiation of, or changes to, antihypertensive drug treatment. Although most of the patients experienced some improvement, blood pressure control was poor. Some clinics showed better performance. Suggestions are made for the development of clinical standards to facilitate appropriate management of this dangerous condition.

Frequency of Serious Outcomes in Patients With Hypertension as a Chief Complaint in the Emergency Department

Context: Hypertension is a common incidental finding in the emergency department (ED). However, the authors noticed a segment of patients who present to the ED specifically because their blood pressure is found to be elevated outside of the hospital. Emergency medicine physicians are often unsure of the level of intervention that is required for these patients.

Objective: To determine if these patients have serious outcomes (ie, final diagnosis of myocardial infarction, angina, coronary syndrome, congestive heart failure, pulmonary edema, hypertensive encephalopathy, malignant hypertension, stroke, transient ischemic attack, subarachnoid hemorrhage, loss of vision, kidney failure, or aortic dissection) within 7 days of the initial ED visit.

Methods: The authors retrospectively reviewed ED medical records from 2008 with a chief complaint of high blood pressure or hypertension in the physician or nursing notes. Age, sex, blood pressure, history of hypertension, associated symptoms, tests, medications, admission or discharge information, final diagnoses, and return visits within 7 days were recorded.

Results: Of the 316 medical records that were reviewed, 149 met the study criteria and were included in analysis. Patient age range was 19 to 94 years (mean, 59.8 years; median, 61 years). Sixty patients (40%) were men and 89 (60%) were women. Of the 149 patients, 121 (81%) had a previous diagnosis of hypertension and 28 (19%) did not. Five patients (3%) had a normal initial blood pressure in the ED. Sixteen patients (11%) did not undergo diagnostic tests, and 77 patients (52%) received medication in the ED. Twenty-six patients (17%) were admitted to the hospital, and 123 (83%) were discharged or eloped. Four patients (2.7%; 95% confidence interval, 0.7-6.7) had a serious outcome noted within 7 days of initial presentation to the ED.

Conclusion: Among patients presenting to the ED with a chief complaint of hypertension or high blood pressure and no serious associated complaint, the risk of serious outcome within 7 days is low.

The importance of diastolic blood pressure in predicting cardiovascular risk

Brachial systolic blood pressure (SBP) is the overall best predictor of future cardiovascular risk for the entire hypertensive population; however, there is much that can be learned from assessing diastolic blood pressure (DBP) in relation to simultaneous levels of SBP, because the former is not distorted by pressure amplification. Low DBP in very young adults (mean age 20 years), presenting as isolated systolic hypertension (ISH), results from elevation in stroke volume and/or arterial stiffness. This subtype of hypertension has a marked male predominance, occurs twice as frequently as essential hypertension, and is potentially not a benign condition. In contrast, isolated diastolic hypertension (IDH) in young adults (mean age of 40 years) with IDH occurs predominantly in men with a high prevalence of metabolic syndrome. Indeed, persons with IDH frequently evolve into systolic-diastolic hypertension and are potentially at increased risk for future diabetes and cardiovascular complications. The older age population with ISH and low DBP (mean age >/=60 years of age) has a high prevalence of left ventricular hypertrophy, increased ventricular-arterial stiffness, and a tendency for diastolic dysfunction and heart failure. Finally, concordant very high DBP, especially in older persons, defines potential hypertensive urgencies, emergencies, secondary forms of hypertension, and other high peripheral resistance states.

The epidemiology and management of severe hypertension

Hypertension guidelines stress that patients with severe hypertension (systolic blood pressure (BP)⩾180 or diastolic BP⩾110 mm Hg) require multiple drugs to achieve control and should have close follow-up to prevent adverse outcomes. However, little is known about the epidemiology or actual management of these patients. We retrospectively studied 59 207 veterans with hypertension. Patients were categorized based on their highest average BP over an 18-month period (1 July 1999 to 31 December 2000) as controlled (<140/90 mm Hg), mild (140–159/90–99 mm Hg), moderate (160–179/100–109 mm Hg) and severe hypertension. We examined severe hypertension prevalence, pattern, duration, associated patient characteristics, time to subsequent visit, percentage of visits with a medication increase, and final BP control and antihypertensive medication adequacy. Twenty-three per cent had ⩾1 visit with severe hypertension, 42% of whom had at least two such visits; median day with severe hypertension was 80 (range 1–548). These subjects were significantly older, more likely black, and with more comorbidities than other hypertension subjects. Medication increases occurred at 20% of visits with mild hypertension compared to 40% with severe hypertension; P<0.05). At study end, 76% of patients with severe hypertension remained uncontrolled; severe hypertension subjects with uncontrolled BP were less likely to be on adequate therapy than those with controlled BP (43.7 vs 45.4%). Among hypertensive veterans, severe hypertension episodes are common. Many subjects had relatively prolonged elevations, with older, sicker subjects at highest risk. Although, follow-up times are shorter and antihypertensive medication use greater in severe hypertension subjects, they are still not being managed aggressively enough. Interventions to improve providers' management of these high-risk patients are needed.

Safety and tolerability of fixed-dose irbesartan/hydrochlorothiazide for rapid control of severe hypertension

This prospective, double-blind, multicenter trial compared the safety and tolerability of irbesartan/hydrochlorothiazide (HCTZ) fixed-dose combination therapy with irbesartan monotherapy in patients with severe hypertension (seated diastolic blood pressure (SeDBP) >or=110 mm Hg, mean BP 172/113 mm Hg at baseline). Patients were randomized 2:1 to 7 weeks' irbesartan/HCTZ 150/12.5 mg to 300/25 mg (n = 468) or irbesartan 150 mg to 300 mg (n = 227). The incidence of treatment-related adverse events (AEs) was similar with combination and monotherapy (11.3% and 10.1%), and most AEs were mild-to-moderate. The combined incidence of prespecified AEs was lower with irbesartan/HCTZ than with irbesartan (8.8% vs. 11.5%). There were no treatment-related serious AEs or deaths. At week 5, more patients achieved SeDBP < 90 mm Hg compared to irbesartan (47% vs. 33%; P = 0.0005). Despite more rapid and aggressive BP lowering, initial fixed-dose irbesartan/HCTZ demonstrated a comparable AE profile to irbesartan monotherapy in patients with severe hypertension.

Oral drugs for hypertensive urgencies: systematic review and meta-analysis

CONTEXT AND OBJECTIVE

Hypertensive urgencies are defined as severe elevations in blood pressure without evidence of acute or progressive target-organ damage. The need for treatment is considered urgent but allows for slow control using oral or sublingual drugs. If the increase in blood pressure is not associated with risk to life or acute target-organ damage, blood pressure control must be implemented slowly over 24 hours. For hypertensive urgencies, it is not known which class of antihypertensive drug provides the best results and there is controversy regarding when to use antihypertensive drugs and which ones to use in these situations. The aim of this review was to assess the effectiveness and safety of oral drugs for hypertensive urgencies.

METHODS

This systematic review of the literature was developed at the Brazilian Cochrane Center, and in the Discipline of Emergency Medicine and Evidence-Based Medicine at the Universidade Federal de São Paulo - Escola Paulista de Medicina (Unifesp-EPM), in accordance with the methodology of the Cochrane Collaboration.

RESULTS

Sixteen randomized clinical trials including 769 participants were selected. They showed that angiotensin-converting enzyme inhibitors had a superior effect in treating hypertensive urgencies, evaluated among 223 participants. The commonest adverse event for calcium channel blockers were headache (35/206), flushing (17/172) and palpitations (14/189). For angiotensin-converting enzyme inhibitors, the principal side effect was bad taste (25/38).

CONCLUSIONS

There is important evidence in favor of the use of angiotensin-converting enzyme inhibitors for treating hypertensive urgencies, compared with calcium channel blockers, considering the better effectiveness and the lower frequency of adverse effects (like headache and flushing).

Asymptomatic hypertension in the emergency department: a matter of critical public health importance

Asymptomatic hypertension (HTN) is commonly encountered in the emergency department (ED), but in most circumstances little is done about it. While many factors may contribute to this, the failure to recognize asymptomatic HTN as a public health problem is particularly important. Given the established long-term consequences of elevated blood pressure (BP), a reconsideration of methods that could enhance surveillance and intervention in the ED is needed. In this article, we discuss the relevant epidemiology of asymptomatic HTN and present a novel approach using a modified version of the Haddon's matrix to systematically address the challenges that contribute to ineffective screening and suboptimal outcomes.

The risks and benefits of initial irbesartan/hydrochlorothiazide combination therapy in patients with severe hypertension

The impact of delays in blood pressure (BP) reduction is particularly relevant for patients with severe hypertension who are at risk for hypertensive emergencies. Combination therapies may hold promise as initial treatment for these patients. The safety and efficacy of initial irbesartan / hydrochlorothiazide (angiotensin receptor blocker / thiazide) treatment was compared with that of irbesartan as monotherapy in a multicenter, double-blind, parallel-group study in patients with severe hypertension. After 5 weeks, 47% of patients receiving combination therapy achieved a target diastolic BP <90 mm Hg compared with 33% with monotherapy (P=.0005). Similarly, systolic BP/ diastolic BP <140 / 90 mm Hg targets were reached by more subjects treated with combination therapy than subjects receiving monotherapy (34.6% vs 19.2%, P<.0001). Initial use of combination therapy instead of monotherapy is estimated to prevent between 250 and 4500 cardiovascular events in every 100,000 severely hypertensive patients over 5 years, without significantly increasing serious adverse event rates.

Initial combination therapy for rapid and effective control of moderate and severe hypertension

Moderate (grade 2) and severe (grade 3) hypertension are important public health problems associated with high cardiovascular risk. Blood pressure (BP) control becomes more difficult to achieve as hypertension progresses. Therefore, early and effective treatment is essential to prevent hypertensive urgencies and emergencies and reduce cardiovascular risk. Currently, less than 50% of patients being treated for moderate or severe hypertension in the United States achieve their BP goal as recommended by treatment guidelines. This review examines the cardiovascular risk and physician inertia associated with moderate and severe hypertension, and concludes that increased use of initial combination therapy can overcome many of the barriers to effective BP control. Furthermore, initial combination therapy with a renin-angiotensin system (RAS) inhibitor and diuretic has the potential to rapidly and effectively reduce BP across a range of baseline BPs, with a comparable adverse event profile to monotherapy.

Emerging insights in the first-step use of antihypertensive combination therapy

The blood pressure (BP) goals set by hypertension management guidelines (<140/90 mm Hg in uncomplicated hypertension; <130/80 mm Hg in type 2 diabetes or kidney disease) are not being achieved in a high proportion of patients, partly because monotherapy is insufficient in many patients. In particular, patients with uncontrolled moderate or severe hypertension and/or associated cardiovascular risk factors remain at high risk for cardiovascular events and hypertensive emergency. In recognition of the urgency of treating moderate and severe hypertension, the Seventh Report of the Joint National Committee on Prevention, Detection, Evaluation, and Treatment of High Blood Pressure (JNC 7) advocates the initial use of 2-drug therapies in patients with systolic BP levels >20 mm Hg above goal or diastolic BP level >10 mm Hg above goal. Regimens should usually include a thiazide diuretic and, for patients with diabetes or kidney disease, an angiotensin-converting enzyme inhibitor or angiotensin receptor blocker. Recently, clinical trial data have shown that first-step antihypertensive treatment of moderate and severe hypertension with carefully chosen fixed-dose combinations provides a high rate of BP goal achievement, a simplified dosing regimen, and superior tolerability compared with monotherapy.

BP goal achievement in patients with uncontrolled hypertension : results of the treat-to-target post-marketing survey with irbesartan

BACKGROUND AND OBJECTIVE

Despite the fact that high BP is a leading risk factor for cardiovascular morbidity and mortality, BP goals are achieved in less than 10-30% of hypertensive patients. Irbesartan alone or in combination with hydrochlorothiazide has been shown to control BP in >70% of hypertensive patients in clinical trials. We set out to investigate the role in clinical practice of irbesartan in improving BP in uncontrolled hypertensive patients with a particular focus on patients with the metabolic syndrome through analysis of data from a post-marketing surveillance study.

METHODS

A multicentre, prospective, post-marketing surveillance study was conducted over 9 months in 14 200 patients aged > or =18 years with previously uncontrolled hypertension (either receiving therapy or newly diagnosed), paying particular attention to a subgroup of patients receiving irbesartan/hydrochlorothiazide as first-line combination therapy. BP was measured by a sphygmomanometer. The main outcome measures were systolic BP (SBP) and diastolic BP (DBP) reduction, response rate (DBP reduction of > or =10mm Hg or to <90 mm Hg), and BP normalisation (SBP <140 and DBP <90 mm Hg) in patients treated with irbesartan alone or in combination with hydrochlorothiazide. Analyses per patient subgroup, previous medication and whether treatment was initiated by the treating physician as first-line combination therapy were conducted. The number and nature of adverse events were documented.

RESULTS

Use of irbesartan 300 mg/day as monotherapy in previously uncontrolled patients resulted in a significant reduction in SBP/DBP (-26.8/-13.3mm Hg, p < 0.0001), which was comparable to the subgroup of patients with the metabolic syndrome (-26.3/-13.0mm Hg, p < 0.0001 vs baseline). Combination therapy (irbesartan 300 mg/hydrochlorothiazide 12.5mg once daily) lowered BP by -27.9/-14.2mm Hg (p < 0.0001) in previously uncontrolled patients; again the subgroup of patients with the metabolic syndrome achieved a comparable BP reduction (-27.5/-14.1mm Hg, p < 0.0001 vs baseline). Overall, no linear dose-response relationship was observed. Use of irbesartan/hydrochlorothiazide as first-line combination therapy was effective (BP normalisation rates between 65.7% and 78.6%) and safe. The mean number of antihypertensive tablets taken was reduced and after a mean period of 9 months, 92% of patients were still taking irbesartan therapy.

CONCLUSION

The study demonstrates that treatment with an irbesartan-based regimen for 9 months results in a strong BP reduction and is feasible as first-line combination therapy. Similar BP reductions were observed in the subgroup of patients with the metabolic syndrome. Compliance with treatment is particularly good, with >90% of patients continuing with treatment after 9 months.

Wavelet entropy characterization of elevated intracranial pressure

Intracranial Hypertension (ICH) often occurs for those patients with traumatic brain injury (TBI), stroke, tumor, etc. Pathology of ICH is still controversial. In this work, we used wavelet entropy and relative wavelet entropy to study the difference existed between normal and hypertension states of ICP for the first time. The wavelet entropy revealed the similar findings as the approximation entropy that entropy during ICH state is smaller than that in normal state. Moreover, with wavelet entropy, we can see that ICH state has the more focused energy in the low wavelet frequency band (0-3.1 Hz) than the normal state. The relative wavelet entropy shows that the energy distribution in the wavelet bands between these two states is actually different. Based on these results, we suggest that ICH may be formed by the re-allocation of oscillation energy within brain.

Prediction of hypertensive crisis based on average, variability and approximate entropy of 24-h ambulatory blood pressure monitoring

Approximate entropy (ApEn) of blood pressure (BP) can be easily measured based on software analysing 24-h ambulatory BP monitoring (ABPM), but the clinical value of this measure is unknown. In a prospective study we investigated whether ApEn of BP predicts, in addition to average and variability of BP, the risk of hypertensive crisis. In 57 patients with known hypertension we measured ApEn, average and variability of systolic and diastolic BP based on 24-h ABPM. Eight of these fifty-seven patients developed hypertensive crisis during follow-up (mean follow-up duration 726 days). In bivariate regression analysis, ApEn of systolic BP (P<0.01), average of systolic BP (P=0.02) and average of diastolic BP (P=0.03) were significant predictors of hypertensive crisis. The incidence rate ratio of hypertensive crisis was 14.0 (95% confidence interval (CI) 1.8, 631.5; P<0.01) for high ApEn of systolic BP as compared to low values. In multivariable regression analysis, ApEn of systolic (P=0.01) and average of diastolic BP (P<0.01) were independent predictors of hypertensive crisis. A combination of these two measures had a positive predictive value of 75%, and a negative predictive value of 91%, respectively. ApEn, combined with other measures of 24-h ABPM, is a potentially powerful predictor of hypertensive crisis. If confirmed in independent samples, these findings have major clinical implications since measures predicting the risk of hypertensive crisis define patients requiring intensive follow-up and intensified therapy.

Efficacy and safety of irbesartan/HCTZ combination therapy as initial treatment for rapid control of severe hypertension

Severe hypertension is difficult to control. This prospective, randomized, double-blind, active-controlled, multicenter trial compared efficacy and safety of once-daily irbesartan/hydrochlorothiazide (HCTZ) combination therapy with irbesartan monotherapy in severe hypertension. Patients who were untreated or uncontrolled on monotherapy (seated diastolic blood pressure [BP] > or =110 mm Hg) received fixed-dose irbesartan 150 mg/HCTZ 12.5 mg combination therapy for 7 weeks, force-titrated to irbesartan 300 mg/HCTZ 25 mg at week 1 (n=468); or irbesartan 150 mg monotherapy, force-titrated to 300 mg at week 1 (n=269). Significantly more patients on combination therapy achieved seated diastolic BP <90 mm Hg at week 5 (primary end point) compared with monotherapy recipients (47.2% vs 33.2%; P=.0005). Likewise, significantly more patients attained goals per the Seventh Report of the Joint National Committee on Prevention, Detection, Evaluation, and Treatment of High Blood Pressure (JNC 7) (<140/90 mm Hg) at week 5 (34.6% vs 19.2%, respectively; P<.0001), while the mean difference between combination and monotherapy in seated diastolic BP and seated systolic BP was 4.7 mm Hg and 9.7 mm Hg (P<.0001). Greater and more rapid BP reduction with irbesartan/HCTZ was achieved without additional side effects.

Elevated platelet P-selectin expression and platelet activation in high risk patients with uncontrolled severe hypertension

BACKGROUND

Uncontrolled severe hypertension is associated with alarming rates of cardiovascular events but the mechanisms of vascular injury are not well understood. Recent investigative interest has focused on platelet activation and platelet P-selectin (CD62P) as direct mediators of vascular inflammation and injury. We investigated the association of extreme blood pressure (BP) elevation with platelet P-selectin and fibrinolytic markers in high risk patients with severe hypertension.

METHODS

Cross-sectional comparison of platelet CD62, tissue plasminogen activator antigen (tPA), and plasminogen activator inhibitor-1 activity (PAI-1) among 3 BP groups: untreated severely hypertensive patients (SHT; n=18), untreated mildly hypertensive patients (MHT; n=19), and normotensive controls (NT; n=16).

RESULTS

Platelet CD62 was greatest in SHT (p=0.00008) and showed a strong correlation with both systolic (p=0.0002, r=0.52) and diastolic (p=0.0003, r=0.52) BP. tPA was greater in SHT than MHT or NT (ANOVA; p=0.02) and correlated with diastolic BP but not SBP. PAI-1 did not correlate with either SBP or DBP but was related to body mass index, diabetes, and dyslipidemia.

CONCLUSIONS

Platelet CD62 demonstrated a strong and graded association with both systolic and diastolic BP that persisted in the presence of multiple concomitant risk factors. The association of BP with CD62P was stronger than with either PAI-1 or tPA-Ag. Platelet activation and platelet CD62 increase in a BP-dependent manner and this relationship persists at extreme levels of BP. Platelet activation and platelet CD62 may participate in the accelerated target organ injury observed in high risk patients with severe hypertension.

Severely increased blood pressure in the emergency department

Patients with severely increased blood pressure often present to the emergency department. Emergency physicians evaluate and treat hypertension in various contexts, ranging from the compliant patient with well-controlled blood pressure to the asymptomatic patient with increased blood pressure to the critically ill patient with increased blood pressure and acute target-organ deterioration. Despite extensive study and national guidelines for the assessment and treatment of chronically increased blood pressure, there is no clear consensus on the acute management of patients with severely increased blood pressure. In this article, we examine the broad spectrum of disease, from the asymptomatic to critically ill patient, and the dilemma it creates for the emergency physician in deciding how and when in the process to intervene.

Effects of severe hypertension on endothelial and platelet microparticles

The molecular mechanisms by which extreme blood pressure elevation leads to vascular injury are not defined. To explore the hypothesis that activation of endothelium and platelets as manifested by increased concentrations of circulating endothelial microparticles and platelet microparticles could play a role in this target organ injury, we conducted a cross-sectional study of these markers in 3 groups: (1) untreated patients referred specifically for treatment of severe uncontrolled hypertension; (2) untreated patients with established mild hypertension; and (3) normotensive volunteer subjects. By ANOVA, endothelial (P=0.002) and platelet (P=0.01) microparticles were greatest in the severely hypertensive group. There was a significant correlation between both of these markers and blood pressure, even in the setting of multiple risk factors. Our results suggest that these markers may be useful and specific for pressure-induced endothelial and platelet activation in hypertension. Furthermore, because of the combined effects of endothelial and platelet microparticles on coagulation, leukocytes, and endothelium, it is possible that they may play a pathogenic role in mediating target organ injury in severe hypertension.

Effects of severe, uncontrolled hypertension on endothelial activation: soluble vascular cell adhesion molecule-1, soluble intercellular adhesion molecule-1 and von Willebrand factor

OBJECTIVES

The molecular mechanisms whereby severe, uncontrolled hypertension (SHT) is translated into acute vascular target organ dysfunction have not been completely defined. We sought to determine whether SHT is associated with pressure-dependent endothelial activation as assessed by soluble vascular cell adhesion molecule-1 (sVCAM-1), soluble intercellular adhesion molecule-1 (sICAM-1) and von Willebrand Factor (vWF).

METHODS

We determined sVCAM-1, sICAM-1 and vWF in three groups: (i) untreated patients referred specifically for treatment of SHT [diastolic blood pressure (DBP) > or = 120 mm Hg; n = 24]; (ii) untreated patients with established mild hypertension (MHT; DBP 95-100 mmHg; n = 19); and (iii) normotensive volunteers (DBP < or = 90; n = 16).

RESULTS

By analysis of variance, sVCAM-1 (P = 0.002), sICAM-1 (P = 0.02) and vWF (P = 0.009) were greater in SHT and MHT than in normotensives but did not differ between SHT and MHT. We observed a significant positive correlation between blood pressure and soluble activation markers at lower blood pressures (normotensives and MHT considered together) that was not present in SHT.

CONCLUSIONS

Even mild elevation of blood pressure may be sufficient to activate the expression of adhesion molecules. Mechanisms other than the endothelial expression of adhesion molecules may be important in mediating the accelerated target organ injury produced by SHT in humans. Concentrations of soluble adhesion molecules and vWF may depend more strongly upon factors in the hypertensive microenvironment other than the absolute level of blood pressure.