Ambulatory blood pressure monitoring in patients with chronic kidney disease and resistant hypertension

J Clin Hypertens (Greenwich). 2012; 14:611–617. © 2012 Wiley Periodicals, Inc. The role of ambulatory blood pressure (BP) monitoring (ABPM) has not been well‐studied in patients with chronic kidney disease and resistant hypertension. In a retrospective study of the outpatient chronic kidney disease population, 156 patients with chronic kidney disease and resistant hypertension who had 24‐hour ABPM and clinic BP measurements were identified. Resistant hypertension was defined as uncontrolled clinic BP while taking ≥3 medications including a diuretic or controlled BP while taking ≥4 medications. Within the study group, ambulatory BP <130/80 mm Hg was found in 35.9% of all patients. Only 6.4% had both ambulatory and clinic BP <130/80 mm Hg. Prevalence of white‐coat hypertension, masked hypertension, and sustained hypertension were 29.5%, 5.8%, and 58.3%, respectively. Compared with patients with sustained hypertension, more patients in the white‐coat hypertension group had low nocturnal average systolic BP (defined as nocturnal average systolic BP <100 mm Hg) (17.4% vs 0%) and low 24‐hour average diastolic BP (defined as 24‐hour average diastolic BP <60 mm Hg) (52.2% vs 22%, P<.01). ABPM provides more reliable assessment of BP in patients with chronic kidney disease and resistant hypertension.     

Effects of the time of antihypertensive drugs administration on the stage of primary open-angle glaucoma in patients with arterial hypertension

Many patients with glaucoma suffer from arterial hypertension (AH). It has been proved that both AH and low blood pressure (BP) at night are important vascular risk factors for primary open-angle glaucoma (POAG). The aims of this study were to assess the severity of pathological changes within the optic nerve and characteristics of blood flow in selected arteries of the eyeball and orbit in patients with POAG and controlled hypertension, in relation to the time of hypotensive drugs administration. Eighty-eight patients with POAG and treated, controlled hypertension were examined. The patients were divided into two subgroups, consisting of group A (n = 43), in whom hypotensive drugs were dosed only in the morning and group B (n = 45), in whom hypotensive drugs were also taken in the evening. In patients who were taking hypotensive drugs also in the evening (group B), there was a statistically significant lower mean perfusion pressure at night, a greater visual field loss and reduced amplitude of evoked potentials. Our analysis showed significantly worse changes in the parameters relating to the optic nerve in patients taking hypertensive medicines in the evening and also significantly lower perfusion pressures at night.     

The effect of correction of sleep-disordered breathing on BP in untreated hypertension

OBJECTIVES: To compare BP response to 3 weeks of nasal continuous positive airway pressure (CPAP) in hypertensive patients with and without sleep-disordered breathing (SDB). DESIGN: A controlled, interventional trial of nasal CPAP in patients with and without SDB. Participants and setting: Twenty-four men, aged 30 to 60 years, with mild to moderate untreated hypertension recruited from employee health and primary care clinics. METHODS: Based on in-laboratory polysomnography, 14 hypertensive patients had SDB, defined by five or more episodes of apnea and hypopnea per hour of sleep (apnea-hypopnea index [AHI], > or = 5), and 10 had no SDB (AHI, < 5). We performed 24-h ambulatory BP monitoring on all patients at baseline, during CPAP, and after CPAP treatment. In patients with an AHI > or = 5, nasal CPAP was titrated to reduce the AHI to < 5. Patients with an AHI < 5 received CPAP of 5 cm H(2)O to control for any potential effect of CPAP per se on BP. Both groups received CPAP for 3 weeks. RESULTS: After adjusting for age and body mass index, the mean nocturnal systolic and diastolic BP changes after CPAP treatment in the SDB group were significantly different from those in the no-SDB group: -7.8 vs +0.3 mm Hg (p = 0.02), and -5.3 vs -0.7 mm Hg (p = 0.03), respectively. There was a similar, although statistically insignificant, difference in the adjusted mean daytime systolic and diastolic BP changes after CPAP treatment between the two groups (-2.7 vs +0.4 mm Hg and -2.3 vs -1.7 mm Hg, respectively). CONCLUSIONS: Three weeks of nasal CPAP treatment of SDB in hypertensive men caused the lowering of nocturnal systolic and diastolic BP values, suggesting that increased nocturnal BP in persons with hypertension was causally related to the apnea and hypopnea events of SDB.     

Therapy of patients with arterial hypertension with fixed dose combination of losartan and hydrochlorothiazide. Effect on 24 hour blood pressure and left-ventricular hypertrophy

Twenty four hour blood pressure (BP) monitoring was carried out and structural state of left ventricular myocardium assessed in 20 patients with mild and moderate hypertension before and after 24 weeks of therapy with Hyzaar - fixed dose combination of losartan (50 mg) and hydrochlorothiazide (12.5 mg). According to data of 24-hour BP monitoring the use of Hyzaar was associated with lowering of diurnal (by 26.9/17.2+/-3/2 mm Hg, p<0.001), nocturnal (by 32.6/18.9+/-3/2 mm Hg, p<0.001), pulse (p<0.001) BP, and rate of morning systolic BP rise (p<0.05), decrease of nocturnal systolic and diastolic BP variability, and improvement of 24-hour BP rhythm. Trough/peak coefficients for systolic and diastolic BP (70 and 76%, respectively) reflected sufficient and steady hypotensive effect throughout 24 hours after single dose of Hyzaar. Target BP level was achieved in 70% of patients. At the background of 24-week treatment with Hyzaar left ventricular myocardial mass index significantly decreased (from 120.1+/-3.5 to 108.6+/-3.1 g/m2, D=11.5+/-1.0, p<0.001) and became normal in 60% of patients. Correlation analysis revealed independence of cardioprotective action of therapy from its hypotensive activity. Thus therapy with Hyzaar produced hypotensive and cardioprotective effects which were independent from each other.     

The different patterns of blood pressure elevation by rofecoxib and nabumetone

Hypertension and knee osteoarthritis (OA) are frequent comorbidities. Nonsteroidal anti-inflammatory drugs (NSAIDs) are often used to relieve pain in such patients. In the last decade selective NSAIDs are used more commonly since they lead to less gastrointestinal complications. As has been shown, the treatment with NSAIDs may cause a mild rise of arterial blood pressure (BP). The influence of selective NSAIDs on BP, particularly in hypertensive patients has still to be investigated. The aim of this study was to determine arterial BP changes in patients suffering from stable arterial hypertension and knee OA and treated with rofecoxib or nabumetone. Two groups of patients with knee OA and stable arterial hypertension received either 25 mg rofecoxib once daily or namebutone 2000 mg once daily during the first week of treatment and 1000 mg for the following 3 weeks. Twenty-four hour arterial BP monitoring was performed prior to initiation of treatment and at the end of a 4-week period. The results were that no changes were found in the mean systolic and diastolic characteristics of BP in the rofecoxib treatment group during day time (delta systolic BP -0.4 mm Hg and delta diastolic BP -0.4 mm Hg), while nocturnal BP increased significantly: delta systolic BP +15.7 mm Hg and delta diastolic BP +8.5 mm Hg. The mean systolic arterial pressure in the nabumeton group raised delta systolic BP 2.9 mm Hg in the daytime and 5 mm Hg during the night-time after the treatment. The mean diastolic arterial pressure also rose delta diastolic 3.2 mm Hg and 4.9 mm Hg at day and night hours respectively. In conclusion rofecoxib treatment did not change arterial BP during day time hours, however, there was a distinct increase in night-time systolic and diastolic BP leading to a disappearance of the physiological diurnal variation. Nabumetone caused a moderate increase of day and night BP, without changes in biological diurnal variation.     

Frequent nurse visits decrease white coat effect in stage III hypertension

Arterial hypertension is a public health problem and patient adherence to treatment is challenging. This study tested whether frequent nurse visits provide additional benefits to antihypertensive treatment. Every 30 days, a pharmacist visited these patients to deliver antihypertensive drugs and perform a pill count. Nurses visited group A (48 patients) every 15 days and group B (52 patients) every 90 days. Ambulatory blood pressure (BP) monitoring was performed 15 and 180 days after randomization. At randomization, groups A and B had the same clinical systolic (191 +/- 5 v 186 +/- 3 mm Hg) and diastolic BP levels (122 +/- 3 v 117 +/- 4 mm Hg), respectively. After 90 days, BP declined more in group A than in group B (35 +/- 5/19 +/- 3 v 27 +/- 5/9 +/- 3 mm Hg). At 180 days, the difference increased because the reduction persisted in group A but decreased in group B (36 +/- 6/21 +/- 4 v 17 +/- 4/10 +/- 2 mm Hg). The mean ambulatory BP monitoring values were similar in both groups at 15 and 180 days. However, the attenuation of the clinic-daytime BP difference was larger in group A than in group B (systolic, -13 +/- 4 v -3 +/- 4 mm Hg; diastolic -11 +/- 3 v -4 +/- 3 mm Hg). The patients with clinic-daytime differences decreased more in group A (systolic, 16 to 10; diastolic, 20 to 14) than in group B (systolic, 19 and 20; diastolic, 22 and 22). These data indicate that frequent nurse visits significantly attenuate the white coat effect (clinic daytime BP difference).     

A multicenter double-blind comparative study of rilmenidine and clonidine in 333 hypertensive patients

The efficacy and acceptability of rilmenidine were studied in a double-blind clonidine-controlled multicenter trial; after a 4-week placebo run-in period, patients with supine diastolic blood pressure (BP) between 95 and 115 mm Hg received as monotherapy either rilmenidine or clonidine over 6 weeks. The initial dose (rilmenidine 1 mg/day or clonidine 0.15 mg/day) was doubled (1 mg or 0.15 mg twice a day, respectively) after 2 weeks if diastolic BP remained greater than or equal to 90 mm Hg. Three hundred and thirty-three patients (mean age 57.8 +/- 0.7 years) with a systolic BP of 170.53 +/- 0.92 mm Hg and a diastolic BP of 101.57 +/- 0.30 mm Hg were randomly divided into 2 homogenous groups (rilmenidine, n = 162 and clonidine, n = 171). All patients taking rilmenidine completed the trial. Seventeen patients taking clonidine (10%, p less than 0.01 vs rilmenidine) were withdrawn because of severe side effects. Systolic and diastolic BP were significantly reduced in both groups at every examination (at 2, 4 and 6 weeks). The mean decreases in supine and erect BP were identical in both groups: systolic BP 19 mm Hg and diastolic BP 12 mm Hg after 6 weeks. BP was normalized (systolic BP less than 160 and diastolic BP less than or equal to 90 mm Hg) in 57% of patients taking rilmenidine and 56% of patients taking clonidine (60% of normalized patients had been taking the single dose in both groups).(ABSTRACT TRUNCATED AT 250 WORDS)     

The association of nocturnal hypertension and nondipping blood pressure with treatment‐resistant hypertension: The Jackson Heart Study

Apparent treatment‐resistant hypertension (aTRH), nocturnal hypertension, and nondipping blood pressure (BP) have shared risk factors. The authors studied the association between aTRH and nocturnal hypertension and aTRH and nondipping BP among 524 black Jackson Heart Study participants treated for hypertension. Nocturnal hypertension was defined by mean nighttime systolic BP ≥120 mm Hg or diastolic BP ≥70 mm Hg. Nondipping BP was defined by mean nighttime to daytime systolic BP ratio >0.90. aTRH was defined by mean clinic systolic BP ≥140 mm Hg and/or diastolic BP ≥90 mm Hg with three medication classes or treatment with four or more classes. The risk for developing aTRH associated with nondipping BP and nocturnal hypertension was estimated. After multivariable adjustment, participants with aTRH were more likely to have nocturnal hypertension (prevalence ratio, 1.20; 95% confidence interval, 1.03–1.39) and nondipping (prevalence ratio, 1.25; 95% confidence interval, 1.09–1.43). Over a median 7.3 years of follow‐up, nocturnal hypertension and nondipping BP at baseline were not associated with developing aTRH after adjustment.     

Effects of aliskiren-based therapy on ambulatory blood pressure profile, central hemodynamics, and arterial stiffness in nondiabetic mild to moderate hypertensive patients

J Clin Hypertens (Greenwich). 2012;00:000–000. ©2012 Wiley Periodicals, Inc. Aliskiren is a direct renin inhibitor that exerts its effect at the rate‐limiting step of the renin‐angiotensin system. This study was performed to examine the beneficial effects of aliskiren‐based antihypertensive therapy on the ambulatory blood pressure (BP) profile, central hemodybamics, and arterial stiffness in untreated Japanese patients with mild to moderate hypertension. Twenty‐one Japanese nondiabetic patients with untreated mild to moderate essential hypertension were initially given aliskiren once daily at 150 mg, and the dose was titrated up to 300 mg as needed. After 12 weeks of aliskiren‐based therapy, the clinic, ambulatory, and central BP values as well as brachial‐ankle pulse wave velocity (baPWV) were all significantly decreased compared with baseline (clinic systolic BP, 151±11 mm Hg vs 132±11 mm Hg; clinic diastolic BP, 91±13 mm Hg vs 82±9 mm Hg; 24‐hour systolic BP, 144±12 mm Hg vs 133±11 mm Hg; 24‐hour diastolic BP, 88±8 mm Hg vs 81±9 mm Hg; central BP, 162±16 mm Hg vs 148±14 mm Hg; baPWV, 1625±245 cm/s vs 1495±199 cm/s; P<.05). These results show that aliskiren, as a first‐line regimen, improves the ambulatory BP profile and may have protective vascular effects in Japanese nondiabetic patients with untreated mild to moderate essential hypertension.     

Clinical value of degree of blood pressure lowering during use of effective doses of antianginal drugs

Paired exercise tests with single doses of verapamil, nifedipine, propranolol, buccal nitroglycerin (trinitrolong), sustained release oral nitroglycerin, and placebo were performed in 101 patients with stable class II-III angina and the drug causing longest exercise duration was selected for long term therapy. Efficacy of a selected drug was compared with magnitude of its hypotensive effect. The latter was calculated as difference between blood pressure (BP) before and 2 hours after drug administration. Lower quintile of distribution of BP differences (systolic BP difference >20 mm Hg and/or diastolic BP difference >15 mm Hg) was considered as excessive hypotensive effect of a study drug (EHESD) single dose. Exercise duration before ST-segment depression was significantly shorter (p<0.05) in cases with EHESD compared with those without EHESD. After 1 month of therapy total daily number of episodes of myocardial ischemia decreased by 3.2+/-3.0 and 1.8+/-1.2 in patients without and with EHESD, respectively (p<0.02). At the same time number of episodes of painless ischemia increased more than 2 times in patients with EHESD (p<0.01). Registration of EHESD at initial stages of treatment with short acting antianginal drugs appears to be a reliable marker of increased frequency of painless episodes of myocardial ischemia and low efficacy of regular use of these drugs.     

The prognostic value of post-exercise blood pressure reduction in patients with hypertensive response during exercise stress test

BACKGROUND: Hypertensive response at peak-exercise and during the recovery phase of exercise stress test (ET) is associated with poor cardiovascular prognosis. We investigated whether decrease in blood pressure (BP) from peak to post-exercise would identify a subgroup at higher cardiovascular risk. METHODS: Eighty-six non-hypertensive patients (0-4 cardiovascular risk factors) with hypertensive reaction at peak-ET (systolic>180 mm Hg and/or diastolic>100 mm Hg) were divided based on BP 5 min after exercise termination into two groups: Normal response (NrmR) (<160/90 mm Hg), Hypertensive response (HypR) (>/=160/90 mm Hg). Five years later the prevalence of cardiovascular risk factors and cardiovascular morbidity and mortality was assessed for each group. RESULTS: Both groups had similar pre- and peak-exercise BP. However the HypR group had higher post-exercise BP (systolic: 163+/-13 vs. 125+/-14 mm Hg, respectively, p<0.01, and diastolic: 74+/-6 vs. 75+/-4 mm Hg, respectively, p<0.01), smaller decrease in BP after exercise (Delta systolic: 46.9+/-3.1 vs. 73.9+/-3.6 mm Hg, respectively, p<0.01, Delta diastolic: 12.4+/-1.5 vs. 26.5+/-2.2 mm Hg, respectively, p<0.01), and higher post- than pre-exercise BP (Delta systolic: 24.5+/-3.5 vs. -6+/-4.1 mm Hg, respectively, p<0.01, A diastolic: 19+/-2.1 vs. -13+/-2.3 mm Hg, respectively, p<0.01). Five years later, HypR group had higher prevalence of abnormal cholesterol serum level (p<0.01), hypertension (p<0.01) and combined ischemic heart disease and cerebrovascular disease (RR 1.32, 95% CI=1.13-1.54, p<0.01). CONCLUSION: During ET evaluation, it is important to evaluate the BP at 5 min after exercise because reduced BP drop, at this routinely measured point, identifies a subgroup with higher cardiovascular risk.     

原发性高血压患者血压变异性与早期肾损害

目的探讨血压变异性(BPV)和原发性高血压患者早期肾损害的关系。方法根据尿白蛋白与尿肌酐比值(UACR)把181例原发性高血压患者分为两组,UACR≤30mg/g为单纯高血压组(A组,120例),UACR>30mg/g为合并早期肾损害组(B组,61例),行24h动态血压监测,BPV以血压标准差和变异系数表示,用Pearson相关分析和多元线性回归分析比较两组患者BPV和早期肾损害之间的关系。结果两组患者各个时段的血压均值差异无统计学意义(P>0.05);除白昼收缩压变异性外,A组和B组24h收缩压变异性[标准差(13.6±3.0)比(15.3±4.1)mmHg;变异系数(0.11±0.02)比(0.12±0.03)]、24h舒张压变异性[标准差(9.6±2.6)比(11.8±4.2)mmHg;变异系数(0.13±0.04)比(0.15±0.05)]、白昼舒张压变异性[标准差(9.5±3.0)比(11.3±4.6)mmHg;变异系数(0.12±0.04)比(0.14±0.06)]、夜间收缩压变异性[标准差(10.0±3.9)比(13.2±4.7)mmHg;变异系数(0.08±0.03)比(0.11±0.04)]和夜间舒张压变异性[标准差(7.7±3.7)比(10.0±3.8)mmHg;变异系数(0.11±0.05)比(0.14±0.05)]差异均有统计学意义(均P<0.05)。Pearson相关分析显示UACR与24h收缩压变异性、24h舒张压变异性、白昼舒张压变异性、夜间收缩压变异性及夜间舒张压变异性呈正相关(均P<0.01)。多元线性回归分析显示UACR与夜间收缩压变异性、24h舒张压变异性、夜间舒张压水平和三酰甘油呈正相关(均P<0.05)。结论原发性高血压患者夜间收缩压变异性、24h舒张压变异性、夜间舒张压水平和三酰甘油与早期肾损害相关。     

Effect of intravenous enalaprilat in moderate and severe systemic hypertension

The antihypertensive effect and tolerability of enalaprilat, an intravenously administered angiotensin converting enzyme inhibitor, was studied in 65 patients with moderate or severe hypertension. In this randomized, double-blind study, enalaprilat was compared with placebo in 42 (22 enalaprilat, 20 placebo) moderate hypertensive (diastolic blood pressure [BP] 100 to 114 mm Hg) patients. It was compared with furosemide in 23 (12 enalaprilat, 11 furosemide) severe hypertensive (diastolic BP 115 to 130 mm Hg) patients. Enalaprilat (1.25 or 5.0 mg), placebo (5% dextrose) or furosemide (40 or 80 mg) was given every 6 hours intravenously up to 48 hours. In the moderate hypertension stratum, the mean supine diastolic BP was significantly (p less than or equal to 0.01) reduced from baseline at all timepoints in the enalaprilat group. These diastolic BP reductions were significantly (p less than or equal to 0.01) greater in the enalaprilat group than the placebo at 1 to 24 hours (-12 vs -4 mm Hg), with 59% of the patients responding to enalaprilat compared with 30% of the patients responding to placebo. An even greater reduction (p less than or equal to 0.01) was seen at 25 to 48 hours (-14 vs -7 mm Hg, with 73% enalaprilat vs 58% placebo responders). Significant (p less than or equal to 0.01) reductions in mean, supine systolic BP were also seen at 1 to 24 hours (-22 vs -2 mm Hg) and 25 to 48 hours (-24 vs -8 mm Hg) during the 48 hours of the double-blind treatment phase in the enalaprilat group compared with placebo.(ABSTRACT TRUNCATED AT 250 WORDS)     

Comparative effects of fenoldopam mesylate and nitroprusside on left ventricular performance in severe systemic hypertension.

To compare the effects of fenoldopam (n = 15), a selective dopamine-1 agonist, and nitroprusside (n = 14) on left ventricular (LV) function in severely hypertensive subjects (diastolic blood pressure (BP) greater than 120 mm Hg), both agents were infused to reduce diastolic BP by 40 mm Hg (or less than 110 mm Hg). Indexes of LV systolic and diastolic functions were obtained using gated radionuclide angiography before the initiation of treatment and after targeted BP was achieved. Both fenoldopam and nitroprusside effectively reduced systolic and diastolic BP to target levels. Changes in heart rate, peak filling rate and relative end-diastolic volume were similar with both agents. Baseline ejection fraction increased after infusion of both drugs. The magnitude of the increase in ejection fraction was far greater with fenoldopam than with nitroprusside (+22% vs +8%; p = 0.04), despite a lesser reduction in systolic BP (-12 vs -22%, p = 0.002). Furthermore, the reduction in relative end-systolic volume (-35 vs -20%; p = 0.04), and increase in the ratio of peak systolic pressure to relative end-systolic volume (+43 vs +6%; p = 0.007) were greater after fenoldopam than after nitroprusside. The greater increment in parameters of LV systolic function produced by fenoldopam than by nitroprusside suggests an effect on LV performance that is independent of afterload reduction.     

Comparison of acebutolol with and without hydrochlorothiazide versus carvedilol with and without hydrochlorothiazide in black patients with mild to moderate systemic hypertension.

In the present study, we assessed the antihypertensive efficacy of acebutolol 200 mg versus carvedilol 25 mg once daily, given as monotherapy for 3 months to 40 black patients (20 patients in each group, mean age 53+/-10 years, 24 women) with mean blood pressure (BP) during the day >90 and <110 mm Hg. Patients in whom blood pressure could not be controlled took medication, which was increased at 3-month intervals as follows: step 2, acebutolol 200 mg or carvedilol 25 mg plus hydrochlorothiazide 12.5 mg once daily; step 3, acebutolol 400 mg or carvedilol 50 mg plus hydrochlorothiazide 25 mg once daily. Overall, significant but modest BP reduction was achieved with both beta blockers at 3 months. In the acebutolol group, 24-hour BP decreased from 142+/-15/94+/-7 mm Hg to 138+/-16/89+/-8 mm Hg (p<0.005 for diastolic BP at 3 months vs baseline). Mean day BP decreased from 145+/-15/98+/-5 mm Hg to 140+/-14/93+/-7 mm Hg (p<0.05 for systolic BP and p<0.0005 for diastolic BP at 3 months vs. baseline). In the carvedilol group, 24-hour BP decreased from 145+/-11/93+/-6 to 138+/-16/87+/-9 mm Hg (p<0.05 for systolic BP and p<0.005 for diastolic BP at 3 months vs baseline). Mean day BP decreased from 149+/-10/99+/-5 to 141+/-16/91+/-87 mm Hg (p<0.05 for systolic BP and p<0.0005 for diastolic BP at 3 months vs baseline). At 12 months, most patients required combination therapy to achieve BP control. The control (mean day diastolic BP <90 mm Hg) and response (mean day diastolic BP decrease > or =10 mm Hg) rates at 12 months were 59% and 82% in the acebutolol and 78% and 78% in the carvedilol groups, respectively. In conclusion, acebutolol or carvedilol in combination with hydrochlorothiazide, rather than acebutolol or carvedilol alone, should be considered as first-line antihypertensive therapy in black patients with mild to moderate hypertension.     

Is resistant hypertension really resistant?

BACKGROUND: Managing resistant hypertension is difficult and mostly involves expensive testing seeking an underlying secondary cause. This study was undertaken to determine 1) the extent of the white-coat phenomenon in patients with resistant hypertension, and 2) whether 24-h ambulatory blood pressure (BP) monitoring (ABPM) or having BP recorded by a nurse instead of the referring doctor could clarify how many apparently resistant hypertensives actually have controlled BP. METHODS: This study involved 611 patients with BP > or = 140/90 mm Hg who were referred for 24-h ABPM by their specialist or general practitioner, including 277 patients who were taking no antihypertensives (group 1), 216 taking one or two antihypertensive drugs (group 2), and 118 taking at least three antihypertensives in combination (group 3). Each had BP recorded by one of two nurses before 24-h ABPM. Controlled BP was defined as awake ambulatory BP <135/85 mm Hg and the white-coat effect was the difference between the BP recorded by the referring doctor or nurse and the average awake ambulatory BP. RESULTS: Those with resistant hypertension (group 3) were older (61 years (12) v group 1: 46 years (14) and group 2: 56 (14) years; P < .001), but were of similar weight, height, and arm circumference to the other groups. Referral systolic, but not diastolic BP was higher in resistant hypertensives (mean 171/95 v 154/95 mm Hg and 164/94 mm Hg, respectively, P < .001 for systolic BP only). Twenty-eight percent of resistant hypertensives and 32% of those taking no antihypertensive drugs had normal awake ambulatory BP and the white-coat effect attributable to the referring doctor was always greater than that due to the nurse (range 16 to 26/12 to 14 mm Hg v 9 to 17/4 mm Hg, P < .001). Nurse recorded BP was highly sensitive (97%) in identifying awake hypertension but lacked specificity (57%) to replace ABPM. CONCLUSION: Our results show that approximately one in four patients with apparent resistant hypertension referred for ABPM have controlled BP and one-third of patients referred for initial evaluation of office or clinic hypertension have normal BP using ABPM, ie, white-coat hypertension. Twenty-four-hour ABPM appears an appropriate initial step before further investigating or treating patients with apparently resistant hypertension.     

Genetic variation in the natriuretic Peptide system, circulating natriuretic Peptide levels, and blood pressure: an ambulatory blood pressure study

BackgroundIn a large collaborative study (n > 50,000), common variants in the natriuretic peptide (NP) genes were found to be associated with circulating NP levels and also with blood pressure (BP) levels based on office BP measurements (OBPMs). It is unknown if determining an individual's BP by 24-h ambulatory BP measurements (ABPMs) will influence the effect of NP gene variations on BP levels.MethodsWe used rs632793 at the NPPB (NP precursor B) locus to investigate the relationship between genetically determined serum N-terminal pro-brain NP (NT-proBNP) concentrations and BP levels determined by both 24-h ABPMs and OBPMs in a population consisting of 1,397 generally healthy individuals taking no BP-lowering drugs.Resultsrs632793 was significantly correlated with serum Nt-proBNP levels (r = 0.10, P = 0.0003), and participants with the A:A genotype had lower serum Nt-proBNP levels than participants with the G:G genotype (geometric mean (95% confidence interval (CI)): 34.8 (31.5-38.4) pg/ml vs. 48.1 (41.9-55.3) pg/ml, P = 0.0002), but higher 24-h ambulatory BP levels (mean difference (95% CI): 2.0 (0.1-4.1) mm Hg, P = 0.043, for systolic BP and 1.7 (0.4-3.1) mm Hg, P = 0.011, for diastolic BP). Office BP decreased across the genotypes from A:A to G:G, but the differences did not reach statistical significance (P ≥ 0.12).ConclusionsThis study suggests that 24-h ABPMs is a better method than OBPMs to detect significant differences in BP levels related to genetic variance and provides further evidence that the NP system plays an important role in BP regulation.American Journal of Hypertension 2012; doi:10.1038/ajh.2012.96.     

Antihypertensive efficacy of the ACE-inhibitor perindopril in the elderly

To assess the antihypertensive efficacy of the angiotensin-converting enzyme (ACE)-inhibitor, perindopril, in the elderly, patients >65 years of age with supine diastolic blood pressure (BP) > or =90 and < or =110 mm Hg at the end of a 4-week placebo washout period were treated with perindopril 4-8 mg/daily vs placebo using a multicentre, randomised, double-blind, parallel group design. Of the 191 patients entered, 183 completed 8 weeks of double-blind therapy. Average age was 72-73 years. Supine and standing BP at the end of the placebo run-in period were 173/96 vs 168/96 mm Hg. BPs were measured in the morning, 20-25 h after the previous day's dose (ie, at the end of the dosing interval). In the placebo group, supine and standing diastolic BP decreased by 3-4 mm Hg, and systolic BP by 6-7 mm Hg. In the perindopril-group, diastolic BP decreased by 6-7 mm Hg and systolic BP by 10-13 mm Hg (both P < 0.01 vs placebo). These data indicate a substantial placebo response of particularly systolic BP in older hypertensives and indicate the importance of a parallel placebo-group to assess the extent of the actual drug's effect. Perindopril caused additional decreases in diastolic BP by about 2 mm Hg, and in systolic BP by 4-5 mm Hg. The extent of this drug-effect may be less in older vs middle-aged hypertensives.     

Treatment of isolated systolic hypertension with labetalol in the elderly

Antihypertensive therapy with labetalol was evaluated in a prospective, randomized, multicenter, double-blind study of 133 elderly patients with isolated systolic hypertension (standing systolic blood pressure [BP] greater than or equal to 160 mm Hg; diastolic BP less than 95 mm Hg). Following a placebo-washout period, patients received either labetalol (n = 70) or placebo (n = 63), which was titrated as necessary from 100 to 400 mg twice a day over a 6-week period. Once the BP was controlled (standing systolic BP less than 160 mm Hg, and greater than or equal to 10-mm Hg decrease from baseline) or the maximum dosage had been given, patients continued receiving the same regimen until the end of the titration period and throughout a 4-week maintenance period. Blood pressure was controlled in 57 (81%) of 70 of the labetalol-treated patients (86% receiving less than or equal to 200 mg twice a day) compared with 34 (54%) of 63 of the placebo-treated patients. Throughout the active treatment periods, BP was significantly lower in patients treated with labetalol compared with those taking placebo; mean standing systolic BP decreased 26 mm Hg in the labetalol group vs 9 mm Hg in the placebo group. Side effects were generally mild, and the dropout rates due to adverse experiences were similar between treatment groups (14% in the labetalol group vs 10% in the placebo group). In summary, labetalol can effectively lower systolic BP in the elderly without causing adverse orthostatic changes.