A comparison between the oscillometric and the auscultatory method for ambulatory 24 h blood pressure monitoring

OBJECTIVES: To investigate the compatibility between oscillometric and auscultatory methods, and to determine whether one is preferable over the other for ambulatory 24 h blood pressure monitoring. METHODS: For the blood pressure monitoring system we used an A&D TM 2421 device (Takeda), which enabled us to measure the blood pressure simultaneously with the two methods on the same arm. Our investigation included 281 patients (122 women and 159 men, aged 18-85 years) with suspected hypertension or undergoing treatment for hypertension. RESULTS: We obtained 23 531 measurements by the oscillometric method, which was 98% of the maximal possible number, and 81% of the maximal possible number were obtained by the auscultatory methjod. We were able to compare 98% of the paired measurements. The auscultatory method showed a uniform distribution of errors throughout the 24 h. Compared to the auscultatory method, the oscillometry method had fewer errors in the evenings, but more when the subjects were at work. There was a difference in paired single readings between the two methods amounting to 1.4+/-19 mmHg (mean+/-SD) for systolic and -2.4+/-18 mmHg for diastolic readings (auscultatory - oscillometric). The differences in mean values for the 281 cases of 24 h monitoring amounted to 0.7+/- 4 mmHg for systolic and -2.2+/-6 mmHg for diastolic measurements. For the mean systolic blood pressure, we found a difference of 0.3+/-4 mmHg in the daytime and 0.3+/-8 mmHg during the night. The mean diastolic pressures differed by -2.0+/-6 mmHg in the daytime and -1.6+/-8 mmHg during the night. We found only a weak correlation between the differences in the readings by the two methods and systolic blood pressure levels, age, pulse pressure and body mass index, and no correlations between these differences and the diastolic blood pressure levels. CONCLUSION: Although we found a considerable SD on single readings by the two methods, there was a good agreement between the mean values of the 24 h monitoring for the two methods. We obtained a significantly higher success rate by the oscillometric method. The findings suggest that, for this equipment, the oscillometric method is preferable for 24 h ambulatory blood pressure monitoring because it provides a much higher rate of successful readings.     

Limited (6-h) ambulatory blood pressure monitoring is a valid replacement for the office blood pressure by trained nurse clinician in the diagnosis of hypertension

OBJECTIVE: To assess the ability of limited ambulatory blood pressure monitoring as a valid replacement for office blood pressure measurement done to American Heart Association criteria in diagnosing hypertension. METHODS: In all, 105 adults, who had been referred for limited ambulatory blood pressure monitoring, participated in the study. Limited ambulatory blood pressure monitoring consisted of 6 h of blood pressure measurement while ambulatory at the Mayo Clinic, using a SpaceLabs 90207 (SpaceLabs Medical, Issaquah, Washington, USA) collecting six readings per hour for the period of observation. The study participants gave consent for three additional consecutive office blood pressure measurements, using a validated aneroid device, done to American Heart Association criteria, by a single hypertension nurse specialist. RESULTS: Mean systolic blood pressure by limited ambulatory blood pressure monitoring was 137.9+/-14.2 mmHg and for the nurse, 137.9+/-20.1 mmHg. Mean diastolic blood pressure by limited ambulatory blood pressure monitoring was 81.5+/-9.7 mmHg and for the nurse, 74.3+/-11.9 mmHg. The intermethod difference for systolic blood pressure was 0.03+/-12.5 mmHg and diastolic blood pressure, -7.2+/-8.0 mmHg. Using <140/90 as criteria factor, limited ambulatory blood pressure monitoring and the trained nurse agreed 77% of the time on whether the patient was hypertensive. This agreement increased to 81% if the participant's referral blood pressure was >or=140/90. CONCLUSIONS: Limited ambulatory blood pressure monitoring is an excellent replacement for office blood pressure, done to American Heart Association criteria, in diagnosing hypertension. This avoids issues of variability introduced by the observers, such as digit preference and bias, and increases reproducibility of blood pressure measurements. The appropriate normal value for limited ambulatory blood pressure monitoring is <140/90 mmHg compared with <135/85 mmHg used in 24-h ambulatory blood pressure monitoring.     

Loss of nocturnal decline of blood pressure in patients with nasal polyposis

The objective of this study was to assess the blood pressure pattern in patients with nasal polyposis. Twenty-seven patients with nasal polyposis (18 males and 9 females), ranging in age from 15 to 72 years (mean 37.1 years) were eligible for inclusion in the study. All patients were hospitalized overnight before surgery. After the basal blood pressure measurements were taken, non-invasive ambulatory blood pressure monitoring was carried out. Oxygen saturation was measured via a finger probe and venous blood sampling was taken for catecholamine level during the full night. All measurements were repeated 4 months after nasal surgery. Mean values for nocturnal decline in blood pressure and heart rate before surgery were less marked than those measured after surgery. Mean decline values (+/- SD) were; 4.6 +/- 2.4 mmHg for systolic blood pressure, 5.8 +/- 3.8 mmHg for diastolic blood pressure, and 7.9 +/- 3.9 beats/min for heart rate before surgery, 9.3 +/- 2.8 mmHg, 8.5 +/- 4.1 mmHg and 10.4 +/- 4.3 beats/min after surgery (p < 0.01), respectively. Whereas mean and minimum SaO2 (%) significantly increased (p < 0.01), catecholamine levels decreased (p < 0.05 for adrenaline, p < 0.01 for noradrenaline) after surgery. A correlation was found between BMI and blood pressure as well as between duration of obstruction and blood pressure. Patients who snored had higher blood pressure values than those who did not. Our data show that in cases of nasal polyposis, hypoxia, hypercapnia, snoring, and sleep disorders may develop and persons with nasal polyposis and snoring have an increased risk of hypertension and loss of nocturnal decline in blood pressure.     

Diurnal variation of hemodynamic indices in non-dipper hypertensive patients.

The purpose of this study was to elucidate the underlying mechanisms of blunted nocturnal blood pressure reduction in non-dipper hypertensive patients. We studied the diurnal variations in systemic hemodynamic indices and baroreflex sensitivity. In 45 subjects with essential hypertension (24 men; mean age, 49+/-1 years), intra-arterial pressure was monitored telemetrically. Non-dippers were defined as those with a nocturnal reduction of systolic blood pressure of less than 10% of daytime systolic blood pressure. Stroke volume was determined using Wesseling's pulse contour method, calibrated with indocyanine green dilution. Baroreflex sensitivity was calculated as deltapulse interval/deltasystolic blood pressure on spontaneous variations. The mean values of the hemodynamic parameters were calculated every 30 min. Twenty-six subjects were classified as non-dippers. Daytime blood pressure was not significantly different between dippers (149+/-4/87+/-3 mmHg) and non-dippers (147+/-3/82+/-2 mmHg), while the nighttime blood pressure was significantly reduced in dippers (131+/-3/77+/-2 mmHg) but not in non-dippers (145+/-3/80+/-2 mmHg). Nocturnal decreases in both cardiac index and stroke index were smaller in non-dippers (-12.0+/-1.2% and 1.5+/-1.0%) than in dippers (-17.5+/-1.4% and -2.2+/-1.1%). Baroreflex sensitivity significantly increased at nighttime both in dippers (6.5+/-0.6 to 8.0+/-0.7 ms/mmHg) and in non-dippers (5.1+/-0.3 to 6.4+/-0.4 ms/mmHg). Neither daytime nor nighttime baroreflex sensitivity was significantly different between the groups. We conclude that the hemodynamics of non-dipper essential hypertension are characterized by an inadequate nocturnal decrease in cardiac index and stroke index, suggestive of relative volume expansion or malsuppressed sympathetic activity.     

老年阻塞性睡眠呼吸暂停低通气综合征合并高血压患者动态血压变化的研究

目的研究老年高血压合并阻塞性睡眠呼吸暂停低通气综合征患者昼夜血压变化的特点,探讨其在心脑血管疾病的发生、发展中的作用。方法72例研究对象根据诊所血压、24h动态血压和多导睡眠图监测结果分为两组：研究组（阻塞性睡眠呼吸暂停低通气综合征合并高血压,n=36）,平均年龄（68士23．3）岁,体重指数（27．7±2．3）kg／m^2。对照组（单纯性高血压,n=36）,平均年龄（64±18．5）岁,体重指数（26．8±1．8）kg／m^2。比较2组睡眠呼吸暂停昼夜血压的影响。结果2组患者年龄、性别和体重指数的差异性无统计学意义。研究组夜间收缩压（143．2±10．7）mmHg,非杓型血压比率83．3％以及晨起收缩压（146．9±16．1）mmHg均明显高于对照组[（132．2±13．DmmHg、27．5％、（137．2±20．1）mmHg],差异有统计学意义。结论阻塞性睡眠呼吸暂停影响血压昼夜节律的变化。     

Relationship between ambulatory blood pressure monitoring and response of blood pressure in male hypertensive adolescents to exercise

BACKGROUND: High blood pressure in the young has been related to the development of hypertension in adults; hence the importance of identifying adolescents with the risk of developing it.OBJECTIVE: To investigate the relationship between 24 h ambulatory blood pressure monitoring and the response of blood pressure in adolescents to exercise. DESIGN: A prospective and cross-sectional study. METHODS: We classified 101 men aged 13-18 years as obese hypertensive, lean hypertensive, obese normotensive, and lean normotensive. Mean blood pressure and variability were measured with ambulatory blood pressure monitoring, and expressed as 24 h, awake, and sleeping periods. Treadmill tests were also performed. RESULTS: Hypertensives and obese normotensives had higher ambulatory blood pressure monitoring values (P< 0.0001). Systolic blood pressure during sleep in obese subjects was significantly higher than that in lean usbjects (119.9 +/- 9 versus 113.6 +/- 8 mmHg, P < 0.001, obese hypertensives versus lean hypertensives; and 113.6 +/- 2 versus 103.0 +/- 2 mmHg, P < 0.002, obese normotensives versus lean normotensives) and nocturnal drop of systolic blood pressure was lower in obese subjects. We found a significant correlation between systolic blood pressure during ambulatory blood pressure monitoring and systolic blood pressure during moderate and maximal exercise for all periods (P < 0.0001). Blood pressure variability during awake period was higher in subjects with maximum exercise systolic blood pressure >/= 200 mmHg (7.4 +/- 2 versus 6.4 +/- 2%, P < 0.01).CONCLUSION: Systolic blood pressure measured by ambulatory blood pressure monitoring is related to response of systolic blood pressure to exercise and ambulatory blood pressure monitoring can identify groups of subjects at greater than normal risk through their higher blood pressure during sleep. Greater than normal blood pressure variability in adolescents is an indicator of the risk of reaching abnormal exercise values of systolic blood pressure. Higher casual blood pressure than ambulatory blood pressure monitoring values for adolescents should be considered abnormal.     

Sleep disturbance during ambulatory blood pressure monitoring of hypertensive patients

BACKGROUND: Hypertensive patients who fail to exhibit a normal fall in blood pressure at night may have a greater risk of target-organ damage. Sleep, with associated cessation of physical activity, is the principal determinant of nocturnal blood pressure 'dip'. OBJECTIVE: To ascertain whether hypertensive patients, who experience the discomfort of higher cuff-inflation pressures during ambulatory blood pressure monitoring, experience more interference with sleep, manifested by greater nocturnal physical activity. DESIGN: A retrospective case- control study. METHODS: Subjects were selected from a database of 475 patients who had undergone simultaneous 24 h ambulatory blood pressure monitoring and monitoring of physical activity with a wrist-mounted piezoelectric accelerometer. Sixty-one hypertensives (average daytime systolic blood pressure >/= 150 mmHg) were age matched to 61 subjects with average daytime systolic blood pressures 相似文献   

Refractory hypertension and sleep apnoea: effect of CPAP on blood pressure and baroreflex.

This study was undertaken to determine whether abolition of obstructive sleep apnoea (OSA) by continuous positive airway pressure (CPAP) could reduce blood pressure (BP) in patients with refractory hypertension. In 11 refractory hypertensive patients with OSA, the acute effects of CPAP on nocturnal BP were studied during sleep and its longer term effects on 24-h ambulatory BP after 2 months. During a single night's application, CPAP abolished OSA and reduced systolic BP in stage 2 sleep from 138.3 +/- 6.8 to 126.0 +/- 6.3 mmHg. There was also a trend towards a reduction in average diastolic BP (from 77.7 +/- 4.5 to 72.9 +/- 4.5). CPAP usage for 2 months was accompanied by an 11.0 +/- 4.4 mmHg reduction in 24-h systolic BP. In addition, both the nocturnal and daytime components of systolic BP fell significantly by 14.4 +/- 4.4 and 9.3 +/- 3.9 mmHg, respectively. Diastolic BP was reduced significantly at night by 7.8 +/- 3.0 mmHg. In patients with refractory hypertension, acute abolition of obstructive sleep apnoea by continuous positive airway pressure reduces nocturnal blood pressure. These data also suggest that continuous positive airway pressure may reduce nocturnal and daytime systolic blood pressure chronically. Randomised trials are needed to confirm the latter results.     

高血压合并阻塞性睡眠呼吸暂停低通气综合征患者短时血压变异性的影响因素研究

目的:探讨高血压合并阻塞性睡眠呼吸暂停低通气综合征(OSAS)患者短时血压变异性(BPV)的影响因素。方法:选择2017年6月至2019年5月在宁波市第一医院心血管科诊治的153例高血压患者,给予多导睡眠呼吸监测及动态血压监测,根据睡眠呼吸暂停低通气指数(AHI)将患者分四组:单纯高血压作为对照组(41例)、高血压合并轻度OSAS组(36例)、高血压合并中度OSAS组(36例)、高血压合并重度OSAS组(40例)。采用因子分析方法提取影响高血压合并OSAS患者短时血压变异性的公因子,进行多元线性回归分析影响高血压合并OSAS患者短时血压变异性的因素。结果:因子分析纳入可能影响高血压合并OSAS患者短时血压变异性的因素,共提取4个公因子:体重指数、OSAS严重程度相关参数、生活行为习惯、年龄及高血压病程;多元线性回归分析显示OSAS严重程度与高血压合并OSAS患者夜间收缩压短时血压变异性(nSBPARV)及夜间舒张压短时血压变异性(nDBPARV)均存在相关性(β=0.277,P<0.05;β=0.360,P<0.05),对于高血压合并OSAS患者nSBPARV的影响因素依次为OSAS严重程度>年龄及高血压病程(分别为β=0.277,P<0.05;β=0.225,P<0.05),对于nDBPARV的影响因素依次为OSAS严重程度>体重指数(分别为β=0.360,P<0.05;β=0.187,P<0.05)。高血压合并轻度、中度、重度OSAS组的nSBPARV、nDBPARV均较对照组大;且高血压合并重度OSAS组的nSBPARV、nDBPARV、日间收缩压短时血压变异性均大于对照组、高血压合并轻度、中度OSAS组,差异均具有统计学意义(P<0.05)。结论:高血压患者合并OSAS时容易出现夜间短时血压变异性增加,OSAS严重程度是高血压合并OSAS患者夜间血压短时变异性增加的主要因素,肥胖、年龄及高血压病程也是重要影响因素。     

Masked nocturnal hypertension and target organ damage in hypertensives with well-controlled self-measured home blood pressure.

It has been reported that masked hypertension, a state in which patients show normal clinic blood pressure (BP) but elevated out-of-clinic BP by self-measured home BP, is a predictor of cardiovascular morbidity much like sustained hypertension. In addition, nocturnal BP is closely associated with cardiovascular disease. This might mean that ambulatory and self-measured home BP monitoring each provide independent information. We performed ambulatory BP monitoring, self-measured home BP monitoring, echocardiography and carotid ultrasonography in 165 community-dwelling subjects. We subclassified the patients according to the ambulatory and self-measured home BP levels as follows: in the masked nocturnal hypertension group, the self-measured home BP level was <135/85 mmHg and the ambulatory nocturnal BP level was >or=120/75 mmHg; in the normotensive group, the self-measured home BP level was <135/85 mmHg and the ambulatory nocturnal BP level was <120/75 mmHg. The intima-media thickness (IMT) and relative wall thickness (RWT) were greater in the masked nocturnal hypertension group than in the normotensive group (IMT: 0.76+/-0.20 vs. 0.64+/-0.14 mm, p<0.05; RWT: 0.50+/-0.14 vs. 0.41+/-0.10, p<0.05). Even in hypertensives with well-controlled self-measured home BP, elevated ambulatory nocturnal BP might promote target organ damage. We must rule out masked hypertension using self-measured home BP monitoring, and we might also need to rule out nocturnal masked hypertension using ambulatory BP monitoring.     

Office blood pressure measurements overestimate blood pressure control in renal transplant patients

OBJECTIVE: As hypertension is an important risk factor for renal allograft failure, we aimed to assess blood pressure control in renal transplant patients with deteriorating graft function using different methods of blood pressure measurements. METHODS: Forty-nine patients with a graft survival of >1 year, and with more than a two-fold increase in urinary albumin excretion, and/or an increase in serum creatinine level >20% during the previous 12 months, were included. Office blood pressure and home BP were measured, and ambulatory blood pressures were obtained in all patients. RESULTS: The mean office blood pressure (133.2+/-16.3/81.7+/-9.6 mmHg) and 24 h ambulatory blood pressure (133.1+/-12.0/79.8+/-8.3 mmHg) were similar. Home blood pressure in the morning (144.2+/-23.3/87.1+/-12.7 mmHg) and evening (143.2+/-20.6/86.4+/-10.3 mmHg) were significantly higher than ambulatory blood pressure (P<0.001 for both). Only 18% of the patients exhibited a reduction of >or=10% in systolic blood pressure during nighttime while 39% had an overt rise. Adequate blood pressure control was found in 53% of the patients using office blood pressure (<140/90 mmHg), contrasting 29% using home blood pressure (<135/85 mmHg), and 16% using mean 24-h ambulatory blood pressure (<125/80 mmHg). These findings were substantiated by the use of receiver-operating characteristic curve analysis. CONCLUSIONS: Using the 24-h blood pressure as a standard, home blood pressure was superior to office blood pressure in estimating blood pressure control in renal transplant patients. Nocturnal hypertension, however, was observed frequently, adding important clinical information about blood pressure control in this high-risk population.     

Isolated nocturnal hypertension and arterial stiffness in a Chinese population

OBJECTIVE: We reported previously that normotensive Chinese had higher nighttime diastolic blood pressure (BP) compared with non-Chinese. We, therefore, studied the prevalence and characteristics of isolated nocturnal hypertension and its association with arterial stiffness, an intermediate sign of target organ damage. METHODS: We recorded ambulatory BP, the central and peripheral systolic augmentation indexes, the ambulatory arterial stiffness index, and brachial-ankle pulse wave velocity in 677 Chinese enrolled in the JingNing population study (53.6% women; mean age: 47.6 years). RESULTS: The prevalence of isolated nocturnal hypertension (> or = 120/70 mmHg from 22 : 00 to 4 : 00 h) was 10.9%. Patients with isolated nocturnal hypertension, compared with participants with ambulatory normotension (45.8%), were older (53.7 vs. 40.7 years), more often reported alcohol intake (68.9 vs. 51.0%), and had faster nighttime pulse rate (62.8 vs. 60.7 bpm), higher serum cholesterol (5.12 vs. 4.77 mmol/l), and higher blood glucose (4.84 vs. 4.38 mmol/l). They also had higher indexes of arterial stiffness (P<0.05) than participants with ambulatory normotension. Of 74 patients with isolated nocturnal hypertension, only four (5.4%) had hypertension on conventional office BP measurement (> or = 140/90 mmHg). CONCLUSION: Isolated nocturnal hypertension can only be diagnosed by ambulatory BP monitoring, is prevalent among Chinese, and is associated with increased arterial stiffness.     

Different effects of ambulatory blood pressure monitoring on subjective and objective sleep quality

OBJECTIVE: To determine whether ambulatory blood pressure monitoring affects objective and subjective sleep quality in patients tested at home. METHODS: Seventy consecutive patients (40 women and 30 men, aged 53+/-15 years), having ambulatory blood pressure monitoring to monitor the efficacy of antihypertensive treatment or to distinguish between hypertension or white-coat hypertension had an evaluation of their sleep quality on a first night with ambulatory blood pressure monitoring and the three following nights without ambulatory blood pressure monitoring. Ambulatory blood pressure monitoring was performed with an auscultatory device with a measure every 15 min during 24 h. Sleep evaluation criteria were both subjective (sleep quality score and sleep questionnaire) and objective (wrist actigraphy monitoring). Sleep parameters during night 1 with ambulatory blood pressure monitoring were compared with those during night 4 without ambulatory blood pressure monitoring. Usual quality of sleep of the patients was assessed by the mean sleep quality score over 7 consecutive days. RESULTS: The sleep quality score was significantly higher for night 4 than for night 1 (7.3+/-2.1 vs. 5.3+/-2.3; P<0.0001). In contrast, actigraphy parameters (actual sleep time, mean activity score, and fragmentation index) were similar on night 1 and night 4 (6.7+/-1.2 vs. 6.9+/-1.2, 13.2+/-9.8 vs. 12.1+/-8.4, and 31.0+/-14.5 vs. 29.9+/-14.3, respectively). Subjective sleep quality was significantly altered by ambulatory blood pressure monitoring in good sleepers (mean sleep quality score > or =7, 73% of patients) but not in poor sleepers. The effect of ambulatory blood pressure monitoring on subjective sleep quality did not differ between dippers and nondippers. CONCLUSIONS: Objective sleep quality as assessed by wrist actigraphy is not significantly altered by ambulatory blood pressure monitoring, whereas subjective sleep quality is adversely affected in good sleepers.     

Positive effect of CPAP treatment on the control of difficult-to-treat hypertension.

The aim of the present study was to analyse the role of continuous positive airway pressure (CPAP) treatment in patients with difficult-to-control hypertension (DC-HT) and sleep apnoea. An Autoset (ResMed, Sydney, Australia) study was performed in 60 patients diagnosed with DC-HT based on two 24-h ambulatory blood pressure monitorisation (ABPM) studies. CPAP was offered to patients with an apnoea/hypopnoea index (AHI) > or =15 events.h(-1). After 3 months of treatment, repeat ABPM was performed to evaluate the effect of CPAP upon the blood pressure values. A total of 39 (65%) patients received CPAP treatment, but only 33 completed the study. The mean+/-sd systolic and diastolic blood pressures (SBP and DBP, respectively) were 154.8+/-14 and 90+/-8.8 mmHg. Patients had a mean+/-sd AHI of 37.7+/-18.2 events.h(-1). Only three patients presented a dipper nocturnal pressure pattern. CPAP treatment significantly reduced SBP (-5.2 mmHg), and particularly the nocturnal values (-6.1 mmHg), but not DBP. Considering only those patients who tolerated CPAP, the decrease in SBP was greater (-7.3 mmHg). Furthermore, CPAP treatment significantly increased the percentage of patients who recovered the dipper pattern (three (9.1%) out of 33 versus 12 (36.4%) out of 33). Continuous positive airway pressure treatment significantly reduces systolic blood pressure, particularly at night, and normalises the nocturnal pressure pattern in patients with difficult-to-control hypertension and sleep apnoea.     

Nocturnal sleep quality and circadian blood pressure variation.

OBJECTIVE: To verify whether non-dipper behavior is associated with poor nocturnal sleep quality and a higher rate of obstructive sleep apnea than dipper behavior. METHODS: A sample of 36 subjects older than 50 years (mean age = 70 +/- 6.49 years), 8 males and 28 females, 27 (75%) hypertensive and 9 (25%) normotensive, was studied. Nocturnal polysomnography was carried out in the patients' homes. 24-hour ambulatory blood pressure was studied with Spacelabs 90,207 device. The statistical tests used were Student's t test, Pearson's correlation and the Chi-square test. RESULTS: In the overall sample, higher rates of apnea, higher rates of arousal and shorter duration of the REM (rapid eye movement) phase were linked to high levels of nocturnal diastolic blood pressure, with statistical significance (p < 0.01, p < 0.01, p < 0.05 respectively). Sleep fragmentation was associated with the lowest percentages of variation in daytime to nighttime systolic blood pressure (p < 0.03). Apnea rates were significantly higher in the hypertensive group compared to the normal blood pressure population (p = 0.04). We also observed that higher rates of nocturnal apnea corresponded to lower variations in daytime to nighttime systolic blood pressure (p = 0.015) and to a lower dipper index (p < 0.05). Higher indexes of arousal and lower REM latency were associated with higher nocturnal blood pressure, both systolic (p = 0.039 and p = 0.008, respectively) and diastolic (p = 0.003 and p = 0.029, respectively). Sleep efficiency was also negatively correlated with mean levels of nocturnal diastolic blood pressure (p = 0.038). CONCLUSIONS: The quality of nocturnal sleep seems to play an important role in blood pressure levels, particularly in the nocturnal blood pressure profile. A poor quality of nocturnal sleep and the rate of obstructive sleep apnea were associated with non-dipper behavior in the hypertensive population. Sleep evaluation is particularly useful in non-dipper subjects with hypertension.     

Reproducibility of nocturnal blood pressure assessed by self-measurement of blood pressure at home.

To assess the reproducibility of nocturnal blood pressure (BP) during sleep as measured using a self-measurement device at home, we obtained repeated nocturnal home BP at 0200 h and quality of sleep assessment from a diary in 556 subjects (71% women, 62.4+/-11.1 years) in the general population. We used an Omron device (HEM-747IC-N, Omron Healthcare Co., Ltd., Kyoto, Japan), with which the time and frequency of monitoring can be preset and the readings stored. The mean+/-SD of the difference between test-retest BP measurements was 0.7+/-15.1 mmHg systolic and 0.2+/-9.7 mmHg diastolic with a mean interval of 5.9 days. The absolute differences were greater than 10 mmHg in 261 (46.9%) subjects for systolic and 145 (26.0%) subjects for diastolic. There was no evidence of regression to the mean in nocturnal measurements over at least three nights (n=390, p>0.22). The differences (the first minus the second measurement) were large in subjects who experienced sleep disturbance only in the first (n=64, 2.3+/-13.6 mmHg and 1.6+/-9.6 mmHg for systolic and diastolic, respectively) or second sessions (n=56, -4.1+/-16.4 mmHg and -2.5+/-11.4 mmHg) compared with the subjects without sleep disturbance (n=66, 1.5+/-17.8 mmHg and 0.8+/-10.3 mmHg) and those with sleep disturbance (n=370, 0.9+/-14.5 mmHg and 0.2+/-9.3 mmHg) in both sessions. In conclusion, the reproducibility of single nocturnal BP as assessed using a self-measurement device at home was not good, especially for subjects who experienced different quality of sleep in each session. To evaluate nocturnal BP using a self-measurement device, estimation of quality of sleep is indispensable.     

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.     

Analysis of blood pressure in children and adolescents reporting siesta during ambulatory blood pressure monitoring

BACKGROUND: In adults, a siesta yields a blood pressure profile similar to that seen in nocturnal sleep. It is therefore stressed that siestas should not be included in daytime blood pressure measurement. OBJECTIVES: To evaluate blood pressure profiles in pediatric and adolescent patients who reported a siesta during 24 h ambulatory blood pressure monitoring (ABPM). METHODS: Patients' diaries of actual sleep times were used to determine the periods of sleep (night-time and siesta) and daytime wakefulness. Ambulatory systolic and/or diastolic daytime and/or night-time hypertension was determined by comparing patients' measurements with normal values taken from published standards for healthy children and adolescents. Data obtained from 12 patients with ambulatory normotension and 12 patients with ambulatory hypertension, who were referred for an evaluation of hypertension or management of known hypertension, were analysed separately. RESULTS: Mean systolic (SBP) and diastolic (DBP) blood pressure values during the daytime awake period were significantly higher than the mean values for the period of daytime, including the siesta, both in patients with ambulatory normotension and in those with ambulatory hypertension (P<0.001 and P<0.01 for SBP and DBP, and P<0.001 and P<0.001 for SBP and DBP, respectively). The percentage night-time falls in SBP and DBP were 12.9+/-0.5 and 19.1+/-1.4 in patients with ambulatory normotension, and 7.1+/-1.5 and 12.9+/-2.2 in patients with ambulatory hypertension. These values were significantly higher when the siesta was excluded from the analysis in both groups (13.9+/-0.5% and 20.7+/-1.5%, P<0.001 and P<0.01 for SBP and DBP in patients with ambulatory normotension; 8+/-1.6% and 14.8+/-2.4%, P<0.001 and P<0.001 for SBP and DBP in patients with ambulatory hypertension, respectively). CONCLUSIONS: By ignoring the effect of the siesta, both the calculation of daytime blood pressure values and the analysis of day-night variability in children and adolescents undergoing ABPM may be erroneously interpreted.     

Assessment of body position to quantify its effect on nocturnal blood pressure under ambulatory conditions

BACKGROUND: Nocturnal blood pressure readings may be influenced by body position because of variation in the vertical distance between heart and cuff level. OBJECTIVES: To quantify the effect of body position on nocturnal blood pressure and to assess whether this effect influences the reproducibility of nocturnal blood pressure. PATIENTS AND METHODS: In 16 individuals (three normotensive and 13 hypertensive) 24 h ambulatory measurement of blood pressure and body position was performed twice, separated by an interval of 2-6 weeks. Body position was measured with five acceleration sensors, which were mounted on the trunk and legs. RESULTS: During the first night, 43 +/- 31% of blood pressure values were measured while participants were in the supine position, 29 +/- 28% when they were lying on their side with the cuffed arm down and 28 +/- 29% when they were lying on their side with the cuffed arm up. During the second night these percentages were 40 +/- 29%, 32 +/- 29% and 28 +/- 25% respectively. Blood pressure readings obtained while individuals were lying with the cuffed arm up were about 10 mmHg lower than those obtained with the individual in either the supine position or lying with the cuffed arm down. After correction for the underestimation attributable to 'cuff-up' readings, nocturnal blood pressure increased by 3 mmHg and the number of non-dippers increased from two to four. Correction did not affect the reproducibility of nocturnal blood pressure measurements (standard deviation of the differences 8.3 mmHg for systolic and 6.0 mmHg for diastolic blood pressure after correction). Dipping status was reproduced in 88% of individuals before correction, and in 87% after correction. CONCLUSIONS: Under ambulatory conditions, a highly variable but sometimes substantial number of blood pressure readings are taken with the cuffed arm above heart level. These readings result in underestimation of nocturnal blood pressure and hence influence dipper-non-dipper classification. However, body position does not seem to have an important influence on the reproducibility of nocturnal blood pressure or dipping status.     

Experience with noninvasive ambulatory 24-hour blood pressure recording in a community hospital.

In 40 subjects (23 treated with antihypertensive medication), 24-h ambulatory blood pressure was measured with an oscillometric blood pressure monitor (Spacelabs model 90202). We studied applicability in the out-patient department with regard to patient tolerance, correlation with mercury manometer measurements, 24-h blood pressure variability and the use in detecting "white-coat" hypertension. The measurements were tolerated quite well except for complaints of sleep disturbance and local irritation from the cuff. The average percentage of missed measuring points was 9.2%. Correlation between blood pressure with the mercury manometer and the Spacelabs monitor (averages of three consecutive readings) was: systolic 0.87 and diastolic 0.73 (P less than 0.001). No evidence for systematic error between the two methods was found. Diurnal blood pressure variation was significant with an average night-time drop of 12 +/- 15 mmHg systolic and 12 +/- 11 mmHg diastolic. "Office" blood pressure measured with the Spacelabs monitor was in the hypertensive range for 28 patients (systolic greater than or equal to 160 and/or diastolic greater than or equal to 95 mmHg). Only 15 of these subjects still met the hypertension criteria on the basis of mean daytime ambulatory blood pressure values. When ambulatory blood pressures during arbitrary 3-h periods of the daytime were studied, the number of patients with established hypertension did not change. The patients with this "office" or "white-coat" hypertensive response could not be distinguished on the basis of variability in daytime blood pressure.(ABSTRACT TRUNCATED AT 250 WORDS)