Effect of continuous positive airway pressure therapy on 24-hour blood pressure in patients with obstructive sleep apnea syndrome

BACKGROUND: Patients with obstructive sleep apnea syndrome (OSAS) are subject to an increased cardiovascular morbidity including systemic hypertension. Little is known about the effects of treatment with nasal continuous positive airway pressure (CPAP) on systemic hypertension. METHODS: Automated ambulatory 24-h blood pressure (BP) monitoring was performed in 88 consecutive patients who were referred for evaluation of snoring or suspected OSAS. In addition, the long-term effects of CPAP therapy on 24-h BP were assessed. RESULTS: A total of 62 patients had OSAS and 26 habitual snoring. Patients with OSAS had significantly higher mean arterial BP values than snorers (102.7 +/- 10.7 v 94.0 +/- 10.2 mm Hg; P < .01). Multiple stepwise linear regression analysis disclosed that the degree of systemic hypertension was independently associated with the severity of OSAS as determined by the apnea/hypopnea index (R = 0.43; P < .001), but not with age, body mass index, or smoking habits. Of the 62 patients with OSAS, 52 were treated with CPAP and reevaluated after 9 months. The CPAP resulted in a significant decrease in mean arterial BP (from 103.7 +/- 10.4 to 99.1 +/- 10.8 mm Hg; P < .05). For those patients with systemic hypertension whose BP improved with CPAP therapy, 24-h mean pulse pressure at baseline (r = -0.36; P < .05) as well as average heart rate during the day (r = -0.35; P < .05) turned out as predictors. CONCLUSIONS: Obstructive sleep apnea syndrome contributes, at least in part, to the development of systemic hypertension, and CPAP may improve BP values in treated OSAS patients. Predictors of a beneficial CPAP effect on BP are a high heart rate and a high pulse pressure before treatment.     

Long-term effect of continuous positive airway pressure on BP in patients with hypertension and sleep apnea

OBJECTIVE: To analyze the long-term effect of continuous positive airway pressure (CPAP) on ambulatory BP in patients with obstructive sleep apnea (OSA) and hypertension, and to identify subgroups of patients for whom CPAP could be more effective. METHODS: We conducted a prospective, long-term follow-up trial (24 months) in 55 patients with OSA and hypertension (mean CPAP use, 5.3 +/- 1.9 h/d [+/- SD]). Twenty-four-hour ambulatory BP monitoring (ABPM) was measured at baseline and after intervention with CPAP on an intention-to-treat basis. In addition, the correlation between the changes in 24-h mean arterial pressure (24hMAP) and CPAP compliance, OSA severity, and baseline ABPM was assessed. RESULTS: At the end of follow-up, a significant decrease was shown only in diastolic BP (- 2.2 mm Hg; 95% confidence interval [CI], - 4.2 to - 0.1; p = 0.03) but not in 24hMAP or other ABPM parameters. However, a correlation between changes in 24hMAP and baseline systolic BP (r = - 0.43, p = 0.001), diastolic BP (r = - 0.38, p = 0.004), and hours of use of CPAP (r = - 0.30, p = 0.02) was observed. A significant decrease in the 24hMAP was achieved in a subgroup of patients with incompletely controlled hypertension at entry (- 4.4 mm Hg; 95% CI, - 7.9 to - 0.9 mm Hg; p = 0.01), as well as in those with CPAP compliance > 5.3 h/d (- 5.3 mm Hg; 95% CI, - 9.5 to - 1.2 mm Hg; p = 0.01). Linear regression analysis showed that baseline systolic BP and hours of CPAP were independent predictors of reductions in BP with CPAP. CONCLUSION: Long-term CPAP reduced BP modestly in the whole sample. However, patients with higher BP at entry and good CPAP compliance achieved significant reductions in BP.     

The effects of continuous positive airway pressure on prehypertension and masked hypertension in men with severe obstructive sleep apnea

Obstructive sleep apnea and hypertension are common conditions that frequently coexist. Continuous positive airway pressure (CPAP) reduces blood pressure in patients with obstructive sleep apnea and sustained hypertension. However, the impact of CPAP on patients with obstructive sleep apnea and prehypertension and masked hypertension, conditions associated with increased cardiovascular risk, is unknown. Thirty-six male patients (age, 43 ± 7 years; body mass index, 28.8 ± 3.0 kg/m(2)) with untreated severe obstructive sleep apnea (apnea-hypopnea index, 56 ± 22 events/hr on polysomnography) with diagnostic criteria for prehypertension and/or masked hypertension, based on office and 24-hour ambulatory blood pressure monitoring, respectively, were studied. The patients randomized to no treatment (control; n=18) or CPAP (n=18) for 3 months had similar frequency of prehypertension and masked hypertension at study entry. There were no significant changes in blood pressure in patients randomized to the control group. In contrast, patients randomized to CPAP presented significant reduction in office systolic (from 126 ± 5 to 121 ± 7 mm Hg; P=0.001) and a trend for diastolic blood pressure (from 75 ±7 to 73 ± 8 mm Hg; P=0.08) as well as a significant decrease in daytime and nighttime systolic and diastolic blood pressure (P<0.05 for each comparison). There was a significant reduction in the frequency of prehypertension (from 94% to 55%; P=0.02) and masked hypertension (from 39% to 5%; P=0.04) only in the CPAP group. In conclusion, effective CPAP therapy promotes significant reduction in the frequency of prehypertension and masked hypertension by promoting significant blood pressure reductions in patients with severe obstructive sleep apnea.     

Effect of indomethacin on blood pressure lowering by captopril and losartan in hypertensive patients

NSAIDs are known to attenuate the effects of some antihypertensive medications. It is not known whether the new class of angiotensin II receptor antagonists is similarly affected. We conducted a multicenter study assessing the effect of indomethacin on the antihypertensive effects of losartan and captopril. After 4 weeks of placebo washout, hypertensive patients received 6 weeks of active antihypertensive therapy with either 50 mg losartan once daily (n=111) or 25 mg captopril twice daily for 1 week, which was increased to 50 mg twice daily for 5 weeks (n=105). This was followed by 1 week of concomitant therapy with indomethacin (75 mg daily). The primary outcome measure was the change in mean 24-hour ambulatory diastolic blood pressure after the addition of indomethacin. Both captopril and losartan significantly lowered ambulatory diastolic blood pressure (losartan -5.3 mm Hg, P:<0.001; captopril -5.6 mm Hg, P:<0.001) after 6 weeks of therapy. Indomethacin significantly attenuated the 24-hour ambulatory diastolic blood pressure for both losartan (2.2 mm Hg, P:<0.05) and captopril (2.7 mm Hg, P:<0.001) and also attenuated the effect of captopril on trough sitting diastolic blood pressure. Changes in daytime diastolic blood pressure (7:00 AM to 11:00 PM) were similar to the 24-hour response in both groups. Nighttime diastolic blood pressure (11:01 PM to 6:59 AM) was significantly attenuated in captopril-treated patients (2.0 mm Hg, P:<0.05), but losartan was unaffected (0.4 mm Hg). Thus, concurrent treatment with indomethacin similarly attenuates the 24-hour antihypertensive response to losartan and captopril.     

Effect of continuous positive airway pressure on ambulatory BP in patients with sleep apnea and hypertension: a placebo-controlled trial

BACKGROUND: Obstructive sleep apnea syndrome (OSAS) is an independent risk factor for arterial hypertension. Several controlled trials have investigated the effect of continuous positive airway pressure (CPAP) on BP in patients with OSAS, but its effect on hypertensive patients has not been analyzed specifically. OBJECTIVE: To analyze the effect of CPAP on ambulatory BP in patients with OSAS and hypertension who were undergoing antihypertensive treatment. Design and patients: We conducted a parallel, randomized, placebo-controlled trial in 68 patients with OSAS and hypertension, who were receiving treatment with antihypertensive medication. Patients were randomly allocated to either therapeutic or subtherapeutic CPAP for 4 weeks. Ambulatory BP was registered at baseline and after treatment. Antihypertensive treatment was not changed during the study. Changes in BP were assessed on an intention-to-treat basis. RESULTS: There were no baseline differences in the apnea-hypopnea index, comorbidities, or ambulatory BP between groups. Objective compliance with CPAP was similar in both the therapeutic and subtherapeutic groups (5.0 +/- 1.4 h/d vs 4.4 +/- 1.9 h/d, respectively; p = 0.13 [mean +/- SD]). There was a small and statistically nonsignificant decrease (- 0.3 +/- 6.3 mm Hg vs - 1.1 +/- 7.9 mm Hg; difference, - 0.8 mm Hg [95% confidence interval, - 2.7 to 4.3]; p = 0.65) in 24-h mean BP (24hMBP) in both subtherapeutic and therapeutic groups after 4 weeks of treatment. No significant changes in systolic, diastolic, daytime, or nighttime BP were observed. The normal circadian dipper pattern was restored in a higher proportion of patients in the therapeutic group compared to the subtherapeutic CPAP group, although differences were not significant (11 of 32 patients vs 3 of 25 patients; odds ratio, 3.84; 95% confidence interval, 0.82 to 20.30; p = 0.10). There was no correlation between the magnitude of change in 24hMBP and CPAP compliance, OSAS severity, or number of antihypertensive drugs used. CONCLUSION: Four weeks of CPAP did not reduce BP in patients with OSAS and hypertension who were treated with antihypertensive medication, compared to placebo group.     

Comparative antihypertensive effects of hydrochlorothiazide and chlorthalidone on ambulatory and office blood pressure

Low-dose thiazide-type diuretics are recommended as initial therapy for most hypertensive patients. Chlorthalidone has significantly reduced stroke and cardiovascular end points in several landmark trials; however, hydrochlorothiazide remains favored in practice. Most clinicians assume that the drugs are interchangeable, but their antihypertensive effects at lower doses have not been directly compared. We conducted a randomized, single-blinded, 8-week active treatment, crossover study comparing chlorthalidone 12.5 mg/day (force-titrated to 25 mg/day) and hydrochlorothiazide 25 mg/day (force-titrated to 50 mg/day) in untreated hypertensive patients. The main outcome, 24-hour ambulatory blood pressure (BP) monitoring, was assessed at baseline and week 8, along with standard office BP readings every 2 weeks. Thirty patients completed the first active treatment period, whereas 24 patients completed both. An order-drug-time interaction was observed with chlorthalidone; therefore, data from only the first active treatment period was considered. Week 8 ambulatory BPs indicated a greater reduction from baseline in systolic BP with chlorthalidone 25 mg/day compared with hydrochlorothiazide 50 mg/day (24-hour mean = -12.4+/-1.8 mm Hg versus -7.4+/-1.7 mm Hg; P=0.054; nighttime mean = -13.5+/-1.9 mm Hg versus -6.4+/-1.8 mm Hg; P=0.009). Office systolic BP reduction was lower at week 2 for chlorthalidone 12.5 mg/day versus hydrochlorothiazide 25 mg/day (-15.7+/-2.2 mm Hg versus -4.5+/-2.1 mm Hg; P=0.001); however, by week 8, reductions were statistically similar (-17.1+/-3.7 versus -10.8+/-3.5; P=0.84). Within recommended doses, chlorthalidone is more effective in lowering systolic BPs than hydrochlorothiazide, as evidenced by 24-hour ambulatory BPs. These differences were not apparent with office BP measurements.     

The comparative effects of azilsartan medoxomil and olmesartan on ambulatory and clinic blood pressure

The current study assesses the antihypertensive efficacy and safety of the investigational angiotensin receptor blocker (ARB), azilsartan medoxomil (AZL-M), compared with placebo and the ARB olmesartan medoxomil (OLM-M). This randomized, double-blind, placebo-controlled, multicenter study assessed change from baseline in mean 24-hour ambulatory systolic blood pressure (SBP) following 6 weeks of treatment. Patients with primary hypertension (n=1275) and baseline 24-hour mean ambulatory systolic pressure ≥ 130 mm Hg and ≤ 170 mm Hg were studied; 142 received placebo and the remainder received 20 mg, 40 mg, or 80 mg AZL-M or 40 mg OLM-M. Mean age of participants was 58 ± 11 years, baseline mean 24-hour SBP was 146 mm Hg. Dose-dependent reductions in 24-hour mean SBP at study end occurred in all AZL-M groups. Reduction in 24-hour mean SBP was greater with AZL-M 80 mg than OLM-M 40 mg by 2.1 mm Hg (95% confidence interval, -4.0 to -0.1; P=.038), while AZL-M 40 mg was noninferior to OLM-M 40 mg. The side effect profiles of both ARBs were similar to placebo. AZL-M is well tolerated and more efficacious at its maximal dose than the highest dose of OLM-M.     

Blood pressure variability and silent cerebral damage in essential hypertension

BACKGROUND: It is recognized that blood pressure (BP) variability has prognostic significance in determining target organ damage and cardiovascular mortality and morbidity. The aim of this study was to analyze the association between blood pressure variability and the presence of silent cerebral white matter lesions in middle-aged asymptomatic essential hypertensives. METHODS: We studied 43 middle-aged untreated hypertensive patients. Blood pressure variabilities (short-term and long-term) were evaluated by using both non-invasive, beat-to-beat, continuous finger 24-hour monitoring (Portapres) and oscillometric automated discontinuous ambulatory blood pressure monitoring. All patients underwent cerebral magnetic resonance imaging to detect the presence or not of white matter lesions. RESULTS: Hypertensive patients with cerebral white matter lesions exhibited significantly higher values of long-term systolic blood pressure variability (standard deviation of 24-hour blood pressure) measured both by continuous beat-to-beat monitoring (16.2 +/- 3.7 v 13.7 +/- 3.6 mm Hg; P = 0.047) and by ambulatory blood pressure monitoring (15.2 +/- 3.8 v 12.8 +/- 2.7 mm Hg; P = 0.022). However, these differences were not independent on blood pressure elevation and did not maintain their significance after adjusting for 24-hour systolic blood pressure. Neither short-term systolic blood pressure variability, nor short-term or long-term diastolic blood pressure variabilities showed differences between patients with and without white matter lesions. CONCLUSION: The present study indicates that long-term systolic blood pressure variability is significantly related to the presence of silent cerebral white matter lesions in essential hypertensive patients, although this relationship is partially dependent on absolute blood pressure elevation.     

The antihypertensive efficacy of the combination of irbesartan and hydrochlorothiazide assessed by 24-hour ambulatory blood pressure monitoring. Irbesartan Multicenter Study Group

In a multicenter, double-blind, randomized trial, 178 patients with ambulatory diastolic blood pressure (BP) > or =85 mm Hg and seated diastolic BP (SeDBP) 95-110 mm Hg received either once-daily irbesartan 75 mg/hydrochlorothiazide (HCTZ) 12.5 mg, irbesartan 150 mg/HCTZ 12.5 mg, or placebo for 8 weeks to assess reductions in 24-hour ambulatory BP and office BP. Safety and tolerability of all treatment regimens were also evaluated. BP results and therapeutic response (trough SeDBP normalized to <90 mm Hg) were expressed as change from baseline to Week 8. Mean reductions in 24-hour ambulatory BP and office seated BP for irbesartan/HCTZ combinations were significantly greater compared with placebo (all, p<0.01). More patients were normalized with irbesartan/HCTZ (65%-69%) than placebo (24%, p<0.01). The frequency of adverse events was similar in all groups. Irbesartan/HCTZ given once-daily appears to be a well-tolerated, safe, and effective antihypertensive treatment.     

Effects of time of day of treatment on ambulatory blood pressure pattern of patients with resistant hypertension

Patients with resistant hypertension present high prevalence of a non-dipper blood pressure pattern. Recent results indicate that non-dipping is related partly to the absence of 24-hour therapeutic coverage in patients treated with single morning doses. Accordingly, we investigated the impact of treatment time on the blood pressure pattern in 700 patients with resistant hypertension on the basis of clinic measurements who were studied by 48-hour ambulatory monitoring. Among them, 299 patients received all their medication on awakening, and 401 were taking > or =1 antihypertensive drug at bedtime. The percentage of patients with controlled ambulatory blood pressure was double in patients taking 1 drug at bedtime (P=0.008). Among the 578 patients with true resistant hypertension, subjects receiving 1 drug at bedtime showed a significant reduction in the 24-hour mean of systolic and diastolic blood pressure (3.1 and 1.6 mm Hg, respectively; P<0.011). This reduction was much more prominent during nighttime (5.1 and 3.0 mm Hg; P<0.001). Accordingly, the diurnal/nocturnal blood pressure ratio was significantly increased by 2.7 and the prevalence on non-dipping reduced (56.9 versus 81.9%; P<0.001) in patients taking 1 drug at bedtime. Compared with patients receiving all drugs on awakening, subjects with 1 drug at bedtime also showed significant reductions in the average values of glucose, cholesterol, fibrinogen, and urinary albumin excretion (P<0.011). In patients with resistant hypertension, pharmacological therapy should take into account when to treat with respect to the rest-activity cycle of each patient to improve control and to avoid the non-dipper pattern associated to higher cardiovascular risk.     

中老年男性高血压患者血压晨峰临床分析

目的 研究中老年男性高血压患者血压晨峰发生情况与血压变异性、降压药物的关系.方法 对2009年1月至2010年12月住院或体检的中老年军人进行问卷及体格检查、实验室检查及动态血压监测,并根据血压晨峰程度是否超过35 mm Hg(1 mm Hg =0.133 kPa)分为晨峰组(101例)和非晨峰组(420例)进行组间比较.结果 中老年男性高血压患者血压晨峰的发生率为19.4％,其中老年和超高龄患者血压晨峰患病率高于中年患者(18.9％、21.8％、5.6％,P＜0.01);与非晨峰组比较,晨峰组具有较高的日间平均收缩压[(132.8±13.3) mm Hg比(128.8±13.3)mm Hg]、空腹血糖水平[(5.96±1.59) mmol/L比(5.68±1.22) mmol/L,P＜0.05]以及24h血压变异性;服用利尿剂组晨峰发生率较未服用组高(27.4％比17.6％,P＜0.05).结论 老年高血压患者易出现血压晨峰现象,空腹血糖水平、24h血压变异性可能是血压晨峰的影响因素,利尿剂可能不利于血压晨峰的控制.     

Randomized placebo-controlled trial of continuous positive airway pressure on blood pressure in the sleep apnea-hypopnea syndrome

Arterial blood pressure rises at apnea termination, and there is increasing evidence that the sleep apnea-hypopnea syndrome (SAHS) is associated with daytime hypertension but no randomized controlled trial evidence of whether SAHS treatment reduces blood pressure exists. We, therefore, conducted a randomized placebo-controlled cross-over study of the effects of 4 wk of continuous positive airway pressure (CPAP) or oral placebo on 24-h blood pressure in 68 patients (55 males, 13 females; median apnea-hypopnea index [AHI], 35) not receiving hypotensive medication. Ambulatory blood pressure was recorded for the last 48 h of each treatment. Epworth Sleepiness Score (ESS) and Functional Outcomes of Sleep Questionnaire (FOSQ) were also recorded. All patients were normotensive. There was a small decrease in 24-h diastolic blood pressure (placebo, 79.2 [SE 0.9] mm Hg; CPAP, 77.8 [SE 1.0] mm Hg; p = 0.04) with the greatest fall occurring between 2:00 A.M. and 9:59 A.M. The observed decrease in 24-h diastolic blood pressure was greater in two a priori groups, CPAP use > or = 3.5 h per night (81.5 [SE 1.2] mm Hg; 79.6 [SE 1.2] mm Hg; p = 0.03) and those with more than twenty 4% desaturations per hour (82.4 [SE 2.1] mm Hg; 77.4 [SE 2.1] mm Hg; p = 0.002). Systolic pressure also fell in the latter group (133.1 [SE 2.8] mm Hg; 129.1 [SE 2.1] mm Hg; p = 0.009). Desaturation frequency was the best predictor of diastolic blood pressure fall with CPAP (r = 0.38; p = 0.002). Both ESS and FOSQ domains improved. Thus, CPAP can reduce blood pressure in patients with SAHS, particularly in those with nocturnal oxygen desaturation, but the decrease is small.     

Changes in home versus clinic blood pressure with antihypertensive treatments: a meta-analysis

Home blood pressure (HBP) monitoring is recommended for assessing the effects of antihypertensive treatment, but it is not clear how the treatment-induced changes in HBP compare with the changes in clinic blood pressure (CBP). We searched PubMed using the terms "home or self-measured blood pressure," and selected articles in which the changes in CBP and HBP (using the upper arm oscillometric method) induced by antihypertensive drugs were presented. We performed a systematic review of 30 articles published before March 2008 that included a total of 6794 subjects. As there was significant heterogeneity in most of the outcomes, a random effects model was used for the meta-analyses. The mean changes (+/-SE) in CBP and HBP (systolic/diastolic) were -15.2+/-0.03/-10.3+/-0.03 mm Hg and -12.2+/-0.04/-8.0+/-0.04 mm Hg respectively, although there were wide varieties of differences in the reduction between HBP and CBP. The reductions in CBP were correlated with those of HBP (systolic BP; r=0.66, B=0.48, diastolic BP; r=0.71, B=0.52, P<0.001). In 7 studies that also included 24-hour BP monitoring, the reduction of HBP was greater than that of 24-hour BP in systolic (HBP; -12.6+/-0.06 mm Hg, 24-hour BP; -11.9+/-0.04 mm Hg, P<0.001). In 5 studies that included daytime and nighttime systolic BP separately, HBP decreased 15% more than daytime ambulatory BP and 30% more than nighttime ambulatory BP. In conclusion, HBP falls approximately 20% less than CBP with antihypertensive treatments. Daytime systolic BP falls 15% less and nighttime systolic BP falls 30% less than home systolic BP.     

Antihypertensive efficacy of olmesartan medoxomil,a new angiotensin II receptor antagonist,as assessed by ambulatory blood pressure measurements

Olmesartan medoxomil is a new angiotensin II receptor blocker. In this randomized, double-blind, placebo-controlled study, the efficacy and safety of olmesartan medoxomil was assessed in 334 patients with moderate to severe essential hypertension. Patients were randomized to receive placebo; 5, 20, or 80 mg olmesartan medoxomil q.d.; or 2.5, 10, or 40 mg olmesartan medoxomil b.i.d. Ambulatory and cuff blood pressure were measured prior to and after 8 weeks of treatment. Treatment with olmesartan medoxomil resulted in a significant placebo-adjusted reduction of mean 24-hour ambulatory diastolic blood pressure of 9.6 mm Hg, 12.2 mm Hg, and 10.6 mm Hg in the 5-, 20-, and 80-mg q.d. groups, respectively. Corresponding reductions in mean ambulatory systolic blood pressure were 14.5 mm Hg, 16.5 mm Hg, and 15.4 mm Hg. Similar reductions of diastolic and systolic blood pressure were seen with b.i.d. dosing. The diastolic trough-to-peak ratios of the q.d. doses of olmesartan medoxomil ranged from 57%-70%, indicating 24-hour effectiveness. The safety profile of olmesartan medoxomil was similar to that of placebo. Olmesartan medoxomil appears to be a safe and effective once-a-day treatment for hypertension.     

Efficacy of combination therapy with amlodipine besylate/benazepril hydrochloride for lowering systolic blood pressure in stage 2 hypertension

The Systolic Evaluation of Lotrel Efficacy and Comparative Therapies (SELECT) study compared daily treatment with combination amlodipine besylate/benazepril hydrochloride 5/20 mg, amlodipine besylate 5 mg, and benazepril hydrochloride 20 mg in 505 patients aged 55 years of age or older with stage 2 hypertension (systolic blood pressure [BP] > or =160 and < or =200 mm Hg and diastolic BP > or =60 and < or =100 mm Hg). BP and pulse pressure were assessed by conventional office BP measurements and 24-hour ambulatory BP monitoring. In this analysis, combination therapy was associated with significantly greater reductions in mean 24-hour BP, pulse pressure, and mean ambulatory BP during various time intervals compared with either monotherapy in the intent-to-treat population, in those with isolated and predominantly systolic hypertension, and in dippers and nondippers. Adverse event rates were low and similar in all treatment groups. This study demonstrated that combination therapy is superior to monotherapy in older patients with stage 2 systolic hypertension and is well tolerated.     

Home monitoring service improves mean arterial pressure in patients with essential hypertension. A randomized, controlled trial

BACKGROUND: Technological advances in the distribution of information have opened new avenues for patient care. Few trials, however, have used telemedicine to improve blood pressure in patients with essential hypertension. OBJECTIVE: To determine the efficacy of a telecommunication service in reducing blood pressure. DESIGN: Randomized, controlled trial. SETTING: University-affiliated primary care outpatient clinics. PATIENTS: 121 adults with essential hypertension who were under evaluation for a change in antihypertensive therapy. INTERVENTION: A home service consisting of automatic transmission of blood pressure data over telephone lines, computerized conversion of the information into report forms, and weekly electronic transmission of the report forms to physicians and patients. MEASUREMENTS: 24-hour ambulatory blood pressure monitoring at baseline and exit. The primary end point was change in mean arterial pressure from baseline to exit. RESULTS: Mean arterial pressure decreased by 2.8 mm Hg in patients receiving the home service and increased by 1.3 mm Hg in patients receiving usual care (P = 0.013 for the difference). Mean diastolic blood pressure decreased by 2.0 mm Hg for home service but increased by 2.1 mm Hg for usual care (P = 0.012 for the difference). Mean systolic blood pressure decreased by 4.9 mm Hg for home service and 0.1 mm Hg for patients receiving usual care (P = 0.047 for the difference). Among African-American patients, mean arterial pressure decreased by 9.6 mm Hg in those receiving home service and increased by 5.25 mm Hg in those receiving usual care (P = 0.047). Part of the decrease in blood pressure for home service was due to more frequent changes in the type or dose of antihypertensive medications. CONCLUSION: This telecommunication service was efficacious in reducing the mean arterial pressure of patients with established essential hypertension.     

老年原发性高血压患者血压晨峰与左心室肥厚的关系

目的探讨老年原发性高血压患者血压晨峰与左心室肥厚的关系。方法选择老年原发性高血压患者80例,根据24 h动态血压监测分为2组:血压晨峰值≥55 mm Hg(1 mm Hg=0.133 kPa)为晨峰组,血压晨峰值<55mm Hg为非晨峰组,每组40例,均常规行超声心动图检查,计算左心室重量指数(LVMI)。结果晨峰组24h、昼间、夜间收缩压及血压晨峰均明显高于非晨峰组(P<0.05),晨峰组LVMI明显高于非晨峰组;左心室肥厚比例明显高于非晨峰组(P<0.05)。结论老年原发性高血压患者血压晨峰与左心室肥厚密切相关。     

A noninferiority comparison of valsartan/hydrochlorothiazide combination versus amlodipine in black hypertensives

The objective of the study was to demonstrate that reduction in mean 24-hour diastolic blood pressure with 160 mg valsartan and 12.5 mg hydrochlorothiazide was not inferior to 10 mg amlodipine in hypertensive blacks. A total of 482 blacks with stage 1 and stage 2 hypertension (mean seated blood pressure 140 to 180/90 to 110 mm Hg) were enrolled in a double-blind, randomized, prospective study. After a placebo run-in period, patients were randomized to 160 mg valsartan or 5 mg amlodipine for 2 weeks, then force-titrated to 160 mg valsartan and 12.5 mg hydrochlorothiazide or 10 mg amlodipine for an additional 10 weeks. Blood pressure was assessed by 24-hour ambulatory blood pressure monitoring. Other assessments included quality of life, peripheral edema, and safety. Noninferiority of valsartan/hydrochlorothiazide to amlodipine was demonstrated by comparable reductions in mean 24-hour diastolic blood pressure with both treatments (-10.2+/-8.6 mm Hg versus -9.1+/-8.3 mm Hg, respectively; P<0.001 for noninferiority), as well as in mean 24-hour systolic blood pressure (-15.9+/-12.1 mm Hg versus -14.5+/-12.2 mm Hg; P<0.001 for noninferiority). The proportion of patients reporting adverse events and the incidence of most events were similar in both treatment groups, although more patients treated with amlodipine reported peripheral edema (5.8% versus 1.7%; P=0.03) and joint swelling (2.9% versus 0%; P=0.008) compared with valsartan/hydrochlorothiazide. We conclude that a starting dose of valsartan/hydrochlorothiazide (160/12.5 mg) is as effective as high-dose amlodipine (10 mg) in reducing blood pressure in blacks with stage 1 and stage 2 hypertension, and valsartan/hydrochlorothiazide is better tolerated.     

Comparative efficacy of two different beta-blockers on 24-hour blood pressure control.

Atenolol and metoprolol succinate, dosed once daily, have different pharmacokinetic profiles. This study tests the hypothesis that differences that are especially noted in the early morning period, when cardiovascular risk is highest, in 24-hour blood pressure (BP) control exist between these 2 beta-blockers. This was a small, randomized open-label study with blinded end point evaluation in 36 hypertensive patients. All participants received hydrochlorothiazide 12.5 mg for 2 weeks before randomization to either 50 mg atenolol or metoprolol succinate given every morning; both treatments were force-titrated to 100 mg/d at 4 weeks. The primary end point was the change in early morning ambulatory systolic BP. Early morning (12 AM-6 AM) systolic BP differences were 3+/-14 mm Hg with atenolol vs -7+/-8 mm Hg with metoprolol succinate (P=.03). The overall 24-hour changes in systolic BP were 1+/-15 mm Hg with atenolol vs -9+/-11 mm Hg with metoprolol (P=.03). In conclusion, metoprolol succinate was more effective in sustaining 24-hour and early morning BP reductions compared with atenolol in a small group of hypertensive patients also treated with once-daily low-dose hydrochlorothiazide. It is possible that differences in outcome between atenolol-based and other therapies may be the result of inadequate dosing of atenolol, a medication that may not be effective for the entire 24-hour period.     

Ambulatory blood pressure in 12-year-old children born small for gestational age

An association between low birth weight and subsequent elevated blood pressure has been demonstrated in a large number of studies, but the number of subjects born small for gestational age in these studies has been negligible. The inverse relationship between birth weight and blood pressure in children has been evaluated previously with an ambulatory blood pressure device, but only in children with normal birth weights. In this prospective case-control study from birth to the age of 12, we evaluated the ambulatory blood pressures in 50 children born at term but small for gestational age and in 50 full-term children born appropriate for gestational age. Children born small for gestational age had similar mean+/-SD systolic (117.5+/-8.5 mm Hg versus 115.3+/-7.4 mm Hg, P=0.221), and diastolic (69.2+/-5.3 mm Hg versus 67.3+/-4.4 mm Hg, P=0.075) 24-hour ambulatory blood pressure compared with the values of the children born appropriate for gestational age. However, 24-hour systolic blood pressure in the small-for-gestational-age children was higher (3.90 mm Hg; 95% confidence interval, 0.65 to 7.15) after adjusting for current body mass index. The difference in current body mass index was the only determinant for the difference in systolic blood pressure between the groups. Birth weight had no direct association with the blood pressure values. Impaired fetal growth may have a relationship with higher later blood pressure, but in 12-year-old children, blood pressure differences between small for gestational age and appropriate for gestational age children are much more dependent on current body size.