Ambulatory blood pressure monitoring in patients with hyperthyroidism before and after control of thyroid function

BACKGROUND AND OBJECTIVE: Thyroid hormones have pronounced effects on the cardiovascular system. Thyrotoxicosis affects blood pressure (BP), modifying both diastolic (DBP) and systolic (SBP) pressures. There are no studies examining BP with ambulatory blood pressure monitoring (ABPM) in hyperthyroidism before and after control of thyroid function. Our aims were (1) to analyse ABPM in a group of normotensive hyperthyroid patients before and after normalizing circulating thyroid hormones and (2) to compare these results with those obtained in a group of euthyroid subjects. PATIENTS AND MEASUREMENTS: We studied 20 normotensive hyperthyroid subjects [18 women; age (mean +/- SEM) 49.0 +/- 3.0 years] and 15 healthy subjects. Patients were evaluated by ABPM over 24 h, at diagnosis and after therapy (n = 18). RESULTS: The average 24-h, daytime and night-time SBP was significantly greater in hyperthyroid patients than in controls with no significant differences in DBP. Circadian BP rhythm, estimated by the difference between mean values of SBP, DBP and mean BP during daytime and night-time, was unchanged. The average 24-h and daytime SBP significantly decreased after normalizing thyroid function in the 18 hyperthyroid evaluated patients. Daytime SBP and DBP were higher than night-time values both before and after control of thyroid function. However, no differences in circadian BP rhythm were observed. CONCLUSIONS: Normotensive hyperthyroid patients exhibit higher ambulatory SBP throughout 24 h than normotensive euthyroid subjects. Control of hyperthyroidism decreases ambulatory SBP values. Mean nocturnal fall in BP is comparable in normotensive hyperthyroid patients and control subjects.     

Ambulatory blood pressure monitoring in obese children: role of insulin resistance

OBJECTIVES: To investigate the relationship between ambulatory blood pressure (ABPM) parameters and insulin resistance in obese children. METHODS: A population of 56 obese prepubertal children was recruited for the study. They underwent ABPM, an oral glucose tolerance test and complete physical examination, including adiposity indexes such as body mass index (BMI), skinfolds, waist-to-hip ratio (WHR) and fat mass. RESULTS: The standard deviation score for BMI was significantly correlated with 24-h systolic blood pressure (SBP) (r = 0.30; P = 0.02) and diastolic blood pressure (DBP) (r = 0.29; P = 0.03), daytime SBP and DBP (r = 0.28; P = 0.04 and r = 0.32; P = 0.02), night-time SBP and DBP (r = 0.32; P = 0.01 and r = 0.27; P = 0.04). Fat mass was correlated with 24-h SBP (r = 0.46; P = 0.005), daytime SBP (r = 0.40; P = 0.01) and night-time SBP (r = 0.49; P = 0.03). No correlations were found between ABPM parameters and WHR. Furthermore, significant correlations were found between insulin resistance indexes, such as the homeostasis model assessment of insulin resistance and quantitative insulin-sensitivity check index, and 24-h DBP (r = 0.34; P = 0.01 and r = -0.29; P = 0.03), daytime DBP (r = 0.35; P = 0.009 and r = -0.34; P = 0.01) and daytime SBP (r = 0.32; P = 0.02 and r = -0.27; P = 0.04). Only 24-h and daytime DBP remained correlated with insulin resistance after adjustment for obesity. The analysis of the circadian rhythm of blood pressure revealed that 24 out the 56 children were non-dippers. CONCLUSIONS: The results of the present study indicate that adiposity and insulin resistance have an important role in influencing blood pressure in obese children, and also show a high prevalence of non-dipping phenomenon. This is of particular relevance because blood pressure tracks from childhood into adulthood and an already early-life high blood pressure is associated with an increased cardiovascular risk.     

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.     

Genetic influence on blood pressure and lipid parameters in a sample of Polish twins

We studied 76 healthy monozygotic (MZ) and same-sex dizygotic (DZ) twin pairs (mean age 35 +/- 8 years, body mass index, BMI, 23.6 +/- 3.9 kg/m2) to determine genetic and environmental contributions to systolic (SBP) and diastolic (DBP) blood pressure, heart rate (HR) and serum lipids [total cholesterol (TC), low-density lipoprotein cholesterol (LDL-chol), high-density lipoprotein cholesterol (HDL-chol) and triglycerides (TG)I. SBP, DBP and HR were measured clinically and by ambulatory blood pressure monitoring (ABPM). Parameters of the genetic models for age-, sex- and BMI-adjusted data were estimated by model fitting and path analysis technique using LISREL 8. We found significant genetic effect on SBP and DBP for both clinical and ABP measurements, ranging from 37% for night-time ambulatory DBP to 79% for daytime ambulatory SBP. Estimates of genetic effects were higher for daytime than night-time ABP values, and higher for ambulatory 24-h SBP than office SBP measurements, with the reverse true for DBP. Significant genetic effect on HR ranged from 59% for office measurements to 69% for 24-h mean values. In summary, we also found genetic effect on TC, LDL-chol and HDL-chol with estimates ranging from 36% to 64%, but not on TG. Furthermore, a shared environmental component for TG was found, estimated at 36%. We showed significant genetic effect on both office and ambulatory BP and HR, with stronger genetic effect on daytime than night-time BP. We also found genetic effect on TC and lipoprotein fractions, but no significant genetic effect on TG. Environmental factors influencing serum TG, such as alcohol consumption, may explain the apparent lack of genetic effect in this healthy, non-obese population.     

Adding hydrochlorothiazide to olmesartan dose dependently improves 24-h blood pressure and response rates in mild-to-moderate hypertension

OBJECTIVE: To test whether adding hydrochlorothiazide (HCTZ) (12.5 or 25 mg) to olmesartan 20 mg improves 24-h blood pressure in patients whose conventional diastolic blood pressure is inadequately controlled by olmesartan monotherapy. PATIENTS: Male and female patients > or = 18 years with mean sitting diastolic blood pressure (DBP) of 100-115 mmHg, mean sitting systolic blood pressure (SBP) greater than 150 mmHg, mean 24-h DBP of at least 84 mmHg, and at least 30% of DBP daytime readings > 90 mmHg. INTERVENTIONS: Four weeks of single-blind treatment with olmesartan 20 mg once daily, followed in non-responders by 8 weeks of randomized double-blind treatment with placebo or HCTZ (12.5 or 25 mg) once-daily, added to olmesartan. RESULTS: HCTZ 25 mg added to olmesartan 20 mg decreased mean daytime DBP significantly more (P = 0.0012) than placebo added to olmesartan 20 mg. Compared to olmesartan monotherapy, mean 24-h DBP and SBP were significantly reduced by combination therapy with olmesartan/HCTZ 20/12.5 mg (-1.9 mmHg, P = 0.0167 and -3.9 mmHg, P = 0.0018, respectively) and 20/25 mg (-3.7 and -7.4 mmHg respectively, P < 0.0001 for both). Mean 24-h DBP and SBP and mean night-time SBP reductions were significantly greater for HCTZ 25 mg than for HCTZ 12.5 mg. Response rates (mean daytime DBP assessed by ambulatory blood pressure measurement < or = 85 mmHg) approximately doubled following the addition of HCTZ (12.5 mg = 57.6% and 25 mg = 69.5%). CONCLUSION: Combination of olmesartan 20 mg with HCTZ provides significantly better 24-h blood pressure reduction than olmesartan monotherapy in patients with mild-to-moderate hypertension. Moreover, increasing the dose of HCTZ from 12.5 to 25 mg is a reasonable step to reach better daytime and night-time blood pressure control.     

Twenty-four-hour ambulatory blood pressure in community-dwelling elderly men and women,aged 60-102 years

OBJECTIVE: To investigate ambulatory blood pressure in elderly people, including 'old elderly' subjects, aged over 80 years. DESIGN: Cross-sectional study of community-dwelling, elderly subjects. METHODS: Subjects were healthy, self-caring, and living independently. Those who were taking medication affecting blood pressure were excluded. Conventional blood pressure was the mean of two measurements. Ambulatory blood pressure monitoring was performed using the SpaceLabs 90207 device. Daytime and night-time blood pressure were defined by fixed clock intervals. RESULTS: Seventy-five 'young elderly', aged 60-79 years, (39 men, 36 women) and 81 'old elderly' aged 80 years and older (37 men, 44 women) underwent 24-h ambulatory blood pressure monitoring. Systolic blood pressure (SBP) was related to age, correlation coefficients between age and SBP were 0.31, 0.25 and 0.31, respectively, for conventional SBP, daytime SBP and night-time SBP (P < 0.01 for all). There was no correlation between age and diastolic blood pressure. Blood pressure levels were similar in men and women. Mean conventional blood pressure, daytime blood pressure and night-time blood pressure were found to be 149/81, 138/82 and 119/69 mmHg, respectively, in the 'young elderly' and 162/82, 147/83, and 133/71 mmHg, respectively, in the 'old elderly (P < 0.01 for SBP). The night : day SBP ratio was significantly higher in the 'old' elderly compared with the 'young' elderly (0.90 versus 0.86, respectively; P < 0.01). CONCLUSIONS: Ambulatory blood pressure levels in healthy, community-dwelling 'old elderly' are higher than those reported for younger adults and reflect the prominent age-related rise in SBP associated with advanced old age. Advanced old age is associated with a diminished nocturnal dip in blood pressure.     

阻塞型睡眠呼吸暂停低通气综合征患者的血压变异性研究

目的 本研究旨在探讨阻塞型睡眠呼吸暂停低通气综合征(OSAHS)患者的睡眠呼吸紊乱指数(AHI)、夜间血氧饱和度及昼夜血压变异性之间的关系.方法 记录51例OSAHS患者的体质量指数、睡眠监测结果(包括呼吸紊乱指数、夜间最低血氧饱和度、夜间平均血氧饱和度)、24 h动态血压结果(包括昼夜平均收缩压和舒张压、白天平均收缩压和舒张压)等.将OSAHS患者的血压变异性分为三组进行讨论.通过SPSS 13.0进行数据统计,分析相关性.结果 本研究共招募患者51例(48.8±13.3)岁.统计结果表明,血压波动类型与OSAHS严重程度有关,重度OSAHS组中,出现异常血压波动的人数比例明显高于另外两组.AHI与昼夜平均收缩压和舒张压、白天平均收缩压、夜间平均收缩压、舒张压均显著相关(P＜0.01),与白天平均舒张压相关(P＜0.05);睡眠中最低血氧饱和度与昼夜平均舒张压相关(P＜0.05),与夜间平均舒张压显著相关(P＜0.01).结论 OSAHS的严重程度是夜间血压升高的一个重要因素,并且影响昼夜血压变异性.无论患者是否被诊断为高血压,24 h动态血压监测在OSAHS患者中都是必要的检查之一.

Abstract：

Objective This study was designed to evaluate the correlations among AHI, night-time SaO2 min,average nocturnal SaO2, HT and 24-h ambulatory blood pressure (24 h-ABP) patterns. Methods All subjects were advised to take a whole night PSG and 24 h-ABP. All data (including average nocturnal SBP and DBP,daytime SBP and DBP) were collected in subjects who met the inclusion criteria.The 24 h-ABP patterns in OSAHS patients were classified into three types. Data analysis was performed using SPSS 13.0 for windows. Results 51 participants (48.8±13.3) y were enrolled in the study.Statistic results suggest that individuals with moderate to severe SDB showed significantly more BP variation. There was statistically significant association between AHI and 24-hour average BP, daytime SBP, nighttime DBP and SBP ( P ＜0.01) ,and also relation between AHI and SBP ( P ＜0. 05). AHI was significantly correlated with increased nighttime BP. Conclusions The severity of OSAHS is an important factor in nocturnal elevation of BP, hence affecting the circadian variation of BP. Noninvasive 24 h-ABP monitoring is an important procedure for understanding the clinical features of OSAHS patients with or without hypertension.     

How to improve the assessment of 24-h blood pressure variability

An increased 24-h blood pressure variability, expressed as SD of 24-h average ambulatory blood pressure values, is associated with target organ damage and cardiovascular risk in hypertension, while a physiological nocturnal blood pressure fall has been associated with reduced cardiovascular risk. Nocturnal blood pressure fall, however, may contribute markedly to the overall blood pressure variability. The aim of our study was to quantitatively assess the contribution of nocturnal blood pressure fall to 24-h blood pressure variability, and to propose a new method for computing 24-h blood pressure variability correcting for nocturnal blood pressure fall. From a large database of ambulatory blood pressure recordings obtained in two hypertension centres (Milan, Italy and Krakow, Poland), we selected 1995 recordings of a sufficiently high quality (> or =70% valid readings, > or =1 measure/h). We calculated (1) blood pressure variability, as SD of 24-h mean blood pressure, both directly from all 24-h individual readings and as a weighted mean of separately computed daytime and night-time blood pressure SD; and (2) the size of nocturnal blood pressure fall. The weighted mean SD of 24-h blood pressure was significantly lower than the corresponding direct 24-h SD of blood pressure. The size of the difference between direct SD and weighted mean SD was strongly correlated with the absolute size of nocturnal blood pressure fall (SD: r=0.89 and 0.86 for systolic and diastolic blood pressures, respectively, P<0.001 for all). The 24-h SD of blood pressure is markedly influenced by the size of nocturnal blood pressure fall, while the weighted mean SD is not. The inclusion of nocturnal blood pressure fall in the calculation of 24-h blood pressure variability may thus lead to the overestimating of this phenomenon. Given that blood pressure variability and fall at night may have opposite prognostic significance, it may be advisable to calculate 24-h SD as the weighted mean of daytime and night-time values, which excludes the interference of night-time blood pressure fall on overall blood pressure variability and allows a more precise assessment of the clinical value of 24-h blood pressure variability. The actual clinical relevance of this new parameter has to be assessed by longitudinal outcome studies.     

Blood pressure in children and adolescents with congenital adrenal hyperplasia (21-hydroxylase deficiency): a preliminary report

BACKGROUND: Classical congenital adrenal hyperplasia (CAH) is characterized by a defect in cortisol and aldosterone secretion, adrenal hyperandrogenism, impaired adrenal medullary function and insulin insensitivity. The latter along with the increased tendency towards obesity raises questions whether other cardiovascular risk factors are altered in CAH. OBJECTIVE: To evaluate 24-h ambulatory blood pressure and obesity in patients with salt-wasting 21-hydroxylase deficiency diagnosed in the neonatal period and treated with hydrocortisone and 9alpha-fludrocortisone thereafter. METHODS: Thirty-eight children (15 males) aged 11.2 years (range 6.1-18.2 years) underwent 24-h ambulatory blood pressure monitoring in the hospital setting. Standard anthropometric measures of height, weight and skinfold thickness were undertaken and body mass index (BMI) derived. All data were expressed as standard deviation scores (SDS) using the UK Growth Reference data. RESULTS: Mean daytime systolic blood pressure SDS (1.8, SD 1.1) was significantly higher than the reference population (P < 0.001), and 58% of patients (67% males; 52% females) had systolic hypertension. Mean daytime diastolic blood pressure SDS (0.8, SD 0.8) was also elevated and 24% (13% males; 37% females) had diastolic hypertension. Eighty-four per cent had absence of the physiological nocturnal dip in systolic blood pressure. Height SDS was similar to the reference population but BMI SDS was higher (P < 0.001). BMI SDS was related to systolic blood pressure SDS (r = 0.34; P = 0.03) and the effect was most marked in females where it was related to measures of truncal fat (r = 0.82; P = 0.002). CONCLUSIONS: Children with salt-wasting 21-hydroxylase deficiency have elevated 24-h ambulatory blood pressure and absence of the physiological nocturnal dip in blood pressure. These abnormalities are associated with a raised BMI, particularly in females. Regular measurement and plotting of blood pressure should be part of the management of children with classical CAH.     

Impact of nocturnal fall in blood pressure on early cardiovascular changes in essential hypertension.

OBJECTIVE: To evaluate in a selected population of subjects with a recent diagnosis of hypertension whether a blunted nocturnal fall in blood pressure is associated with more advanced cardiac and vascular damage. METHODS: One hundred and eleven recently diagnosed and never-treated patients with mild essential hypertension underwent 24-h ambulatory blood pressure monitoring (ABPM), echocardiography and carotid ultrasonography. RESULTS: The 78 patients with normal (> 10%) night-time fall in systolic blood pressure (SBP) and diastolic blood pressure (DBP) (dippers) were similar to the 33 patients with a small (< or = 10 %) fall (non-dippers) for age, sex, body surface area, smoking habit, clinic and 24-h blood pressure. There were no differences between dippers and non-dippers in left ventricular mass index (104 versus 105 g/m2), common carotid internal diameter (5.8 versus 5.9 mm), intima-media thickness (0.66 versus 0.64 mm) and carotid plaques prevalence (25 versus 29%). Furthermore, no differences were found in the correlation of daytime and night-time SBP and DBP with left ventricular mass and carotid wall thickness. When the 77 men and 34 women were analysed separately, similar results were obtained. CONCLUSION: These results suggest that a blunted reduction in night-time blood pressure does not play a major role in the development of cardiovascular changes during the early phase of essential hypertension.     

Differences in exercise blood pressure response between dipper and non-dipper elderly patients with essential hypertension

We evaluated the circadian variation and exercise stress response patterns of blood pressure (BP) in elderly patients with essential hypertension. Ambulatory BP monitoring for 48 hours every 30 minutes, and treadmill exercise test using a Bruce protocol at PM 3 to 5 were performed in 49 untreated patients with hypertension. Mean daytime (awake), and night-time (sleeping) systolic BP (SBP) and diastolic BP (DBP) values were analyzed by reviewing the patients' diaries, and the nocturnal reduction rate (NRR) of SBP and DBP were calculated according to the following formula. NRR (%) = [(daytime mean-nighttime mean)/daytime mean] x 100. The patients were divided into two groups according to the presence (dipper, n = 25) or absence (non-dipper, n = 24) of a reduction in both SBP and DBP during the night by an average of more than 10% of the daytime BP. Mean values of SBP and DBP measured over 48 hours in the dipper and non-dipper groups were similar. Responses of SBP to dynamic exercise at 2 to 5 minutes in the non-dipper group were significantly smaller than those in the dipper group (p < 0.05). Non-dipper patients with hypertension responded to dynamic exercise stress with smaller increases in SBP than did those in the dipper group. The differences in BP responses to exercise may affect the circadian blood pressure profile in dipper and non-dipper elderly patients with essential hypertension.     

Is the nocturnal fall in blood pressure reduced in essential hypertensive patients with metabolic syndrome?

OBJECTIVE: The aim of this study was to examine whether an impaired reduction in nocturnal blood pressure (BP), defined on the basis of two periods of ambulatory BP monitoring (ABPM), is present in hypertensive patients with metabolic syndrome, as defined by the NCEP criteria. METHODS: 460 grade 1 and 2 untreated essential hypertensives (mean age 45.9 +/- 11.9 years) referred for the first time to our outpatient hospital clinic underwent the following procedures: 1) medical history and physical examination; 2) repeated clinic BP measurements; 3) routine examinations; 4) ABPM over two 24-hour periods within 4 weeks. Metabolic syndrome was defined as at least three of the following alterations: increased waist circumference, increased triglycerides, decreased HDL-cholesterol, increased BP, or high fasting glucose. Nocturnal dipping was defined as a night-time reduction in average SBP and DBP >10% compared to average daytime values. RESULTS: The 135 patients with metabolic syndrome (group I) were similar for age, gender and known duration of hypertension to the 325 patients without it (group II). There were no significant differences between the two groups in average 48-hour, daytime, night-time SBP/DBP values and the percentage nocturnal SBP and DBP decrease (-17.7 / -15.7 vs. -18.4 / -16.2, p = ns). A reproducible nocturnal dipping (decrease in BP >10% from mean daytime in both ABPM periods) and non-dipping profile (decrease in BP < or =10% in both ABPM periods) was found in 74 (54.8%) and 29 (21.4%) in group I and in 169 (52.1%) and 73 (22.4%) in group II, respectively (p = ns); 32 patients (23.7%) in group I and 83 patients (25.5%) in group II had a variable dipping profile (p = ns). CONCLUSIONS: This study shows that no significant difference exists in nocturnal BP patterns, assessed by two ABPMs, in untreated essential hypertensive patients with metabolic syndrome compared to those without it.     

Blood pressure, cardiac structure and severity of obstructive sleep apnea in a sleep clinic population.

OBJECTIVES : We investigated whether the severity of obstructive sleep apnea (OSA) predicts blood pressure or cardiac left ventricular thickness in a clinical population of OSA patients, if adjustments are made for age, gender, use of antihypertensive agents, smoking, body mass index, history of coronary artery disease, hypercholesterolemia and circulating C-peptide concentrations. DESIGN : Relationships in this cross-sectional study were investigated with correlation analysis and multiple regression procedures. PATIENTS AND METHODS : Apnea-hypopnea index (AHI, polysomnography) and office systolic and diastolic blood pressures (SBP and DBP) were measured in 81 subjects referred to a university hospital sleep laboratory. Ambulatory blood pressures were recorded during one 24 h cycle. Left ventricular (LV) muscle size was quantified as two-dimensionally directed M-mode-derived end-diastolic thickness of interventricular septum and posterior chamber wall. RESULTS : After adjustment for separate or the entire set of covariates, AHI predicted office SBP and DBP as well as daytime ambulatory DBP and night-time ambulatory SBP and DBP, but not daytime ambulatory SBP. In contrast, associations between AHI and LV muscle thickness reflected complex inter-relationships with confounding variables. Smoking and age suppressed, whereas body mass index (BMI) and hypertension inflated the relationship between OSA severity and LV muscle thickness in this study. CONCLUSIONS : AHI is an independent predictor of several measures of blood pressure. OSA severity and LV muscle thickness appear to be primarily linked via increased blood pressure.     

Rosiglitazone reduces office and diastolic ambulatory blood pressure following 1-year treatment in non-diabetic subjects with insulin resistance

OBJECTIVE: Rosiglitazone (RSG) has been reported to reduce blood pressure (BP) in patients with type-2 diabetes, but similar effects in non-diabetic people with insulin resistance is less clear. Our aim was to test the long-term BP-lowering effects of RSG compared with placebo. METHODS: We recruited participants for BP evaluation of RSG treatment from a larger intervention trial. Office BP was recorded in 355 non-diabetic subjects with insulin resistance randomized to receive either RSG or placebo for 52 weeks. Ambulatory BP monitoring (ABPM; Spacelab 90207) was performed in a subgroup of 24 subjects (RSG: n = 11; placebo n = 13). RESULTS: After 1 year, the office BP decreased by -3.1 mmHg systolic (p<0.05) and -3.8 mmHg diastolic (p<0.001) in the RSG group versus placebo. In patients treated with RSG, at 1 year there was a trend for a reduction from baseline for mean 24-h diastolic BP (DBP), daytime DBP and night-time DBP (-4.39, -5.26 and -2.93 mmHg, respectively). However, only daytime DBP was significantly lower in the RSG group compared with control (adjusted mean difference: -4.41 mmHg, p = 0.007). There was also a non-significant trend for a reduction in mean 24-h systolic BP (SBP), daytime SBP and night-time SBP (-2.70, -2.51 and -3.35 mmHg, respectively). CONCLUSIONS: RSG treatment for 1 year was associated with a small but significant decrease in diastolic 24-h ambulatory diastolic BP, and both systolic and diastolic office BPs in non-diabetic people with insulin resistance.     

A new method for assessing 24-h blood pressure variability after excluding the contribution of nocturnal blood pressure fall

OBJECTIVES: To assess quantitatively the relationship between nocturnal blood pressure (BP) fall and 24-h BP variability; to propose a new method for computing 24-h BP variability, devoid of the contribution from nocturnal BP fall; and to verify the clinical value of this method. METHODS AND RESULTS: We analysed 3863 ambulatory BP recordings, and computed: (1) the standard deviation (SD) of 24-h BP directly from all individual readings and as a weighted mean of daytime and night-time SD (wSD); and (2) the size of nocturnal BP fall. Left ventricular mass index (LVMI) was assessed by echocardiography in 339 of the patients. The 24-h SD of BP was significantly greater than the 24-h wSD. Nocturnal BP fall was strongly and directly related to 24-h SD, the relationship with 24-h wSD being much weaker and inverse. The difference between SD and wSD was almost exclusively determined by the size of nocturnal BP fall. wSD of systolic BP was significantly related to LVMI, while 24-h SD was not. CONCLUSION: Conventional 24-h SD of BP is markedly influenced by nocturnal BP fall. The weighted 24-h SD of BP removes the mathematical interference from night-time BP fall and correlates better with end-organ damage, therefore it may be considered as a simple index of 24-h BP variability superior to conventional 24-h SD.     

Gender difference in the relation blood pressure-left ventricular mass and geometry in newly diagnosed arterial hypertension

Much evidence suggests sexual dimorphism in the relationship linking blood pressure (BP) to both left ventricular mass (LVM) and geometry in hypertension. To better evaluate gender-associated characteristics in the relation BP-LVM among newly diagnosed hypertension (24-h average ambulatory BP monitoring, ABPM, >?125/80 mmHg), we measured indexed LVM and relative wall thickness (RWT) by standardized echographic methods in 209 Caucasian drug-na?ve subjects, of whom 162 (100M/62F) were recognized to be hypertensive. Mean office systolic (SBP)/diastolic (DBP), 24-h average and night-time BP values were similar between sexes and significantly related to indexed LVM in both genders. Daytime SBP was significantly related to indexed LVM only in females (r =0.41; p =0.0008 in women; r =0.11; p = NS in males), while LVM was more sensitive to day-to-night SBP change in females. RWT was, on the contrary, significantly related to ABPM values only in males. All these findings were confirmed after adjusting for possible confounders. Percentage of LVM variance explained by 24-h average, daytime or night-time SBP values were higher in females than in males (17% vs 3%; 11% vs 1%; and 17% vs 8%). In conclusion, in early hypertension, LVM was significantly associated with daytime BP and more sensitive to reduced percentage of night BP fall in females. LVM variance explained by ABPM SBP was much higher in females than in males. RWT, expressing concentric LVM remodelling was, conversely, more related to BP increase in males.     

Relationships between diurnal blood pressure variation, physical activity, and health-related QOL

The aim of this study is to clarify the associations between diurnal blood pressure variation, physical activity and health-related quality of life (HRQOL). Ninety-seven volunteers, including 52 hypertensive patients and 45 healthy subjects (average age, 48 years) participated in this study. Twenty-four hour ambulatory blood pressure and heart rate variability were measured using TM2425 (A&D Co). Physical activity was measured using actigraphy, and HRQOL was assessed by a Medical Outcome Study Short-Forum 36-Item Health Survey (SF-36). Awake mean physical activity positively correlated with the nocturnal dip in systolic blood pressure (SBP) (r = 0.242, p < 0.02) and diastolic blood pressure (DBP) (r = 0.219, p < 0.04). The score of physical functioning positively correlated with awake mean physical activity (r = 0.265, p < 0.02). The score of role-emotional also correlated with awake mean physical activity (r = 0.269, p = 0.01). Using multiple regression analysis, the nocturnal dip in SBP was found to be correlated with awake and sleep mean physical activities (p < 0.05, p < 0.05, respectively). In conclusion, physical activity is associated with the nocturnal dip in blood pressure. Moreover, physical activity correlates with some of the factors of HRQOL.     

肾血管性与原发性高血压患者24h动态血压的比较

目的 比较肾血管性高血压(RVH)与原发性高血压(EH)患者24 h动态血压的差别.方法 应用动态血压监测仪观察51例RVH患者的24 h动态血压,并与年龄、性别与之相匹配的51例EH患者的24 h动态血压进行比较.结果 RVH组24 h、白天及夜间动态收缩压、舒张压及脉压均值都比EH组有不同程度的升高(P<0.05),尤以夜间收缩压升高明显;血压负荷增加明显,24 h收缩压、舒张压负荷分别达到58.96%和35.98%,而EH组血压负荷均在20.00%左右,两组比较差异有统计学意义(P<0.05).EH组夜间血压下降率为10.36%,血压曲线呈勺型(60.8%的患者夜间血压下降率>10%);而RVH组夜间血压下降率为5.39%,血压曲线呈非勺型(仅有27.50%的患者夜间血压下降率>10%).结论 RVH患者动态血压均值、脉压和血压负荷明显增加,昼夜节律减弱.

Abstract：

Objective To compare 24 h ambulatory blood pressure changes between patients with renovascular hypertension and essential hypertension.Methods The 24 h ambulatory blood pressure of patients with age and gender matched renovascular hypertension (RVH, n=51) was compared with that of patients with essential hypertension (EH, n=51).Results The 24 h, daytime and nighttime systolic blood pressures(SBP),diastolic blood pressures(DBP) and pulse pressures (PP) in RVH were significantly higher than in EH (all P<0.05), especially the nocturnal SBP (P<0.05). The SBP and DBP loads in RVH were 58.96% and 35.98% respectively, while blood pressure loads were around 20.00% in EH (P<0.05). In patients with RVH, The nocturnal blood pressure fall was 5.39%, and only 27.50% patients were dippers, while the nocturnal blood pressure fall was 10.36% and 60.8% patients were dippers in EH.Conclusion RVH patients have higher dynamic BP, PP, BP loads and blunted diurnal rhythm compared to those with EH.     

Reproducibility of intra-arterial ambulatory blood pressure: effects of physical activity and posture

OBJECTIVE: To examine the effects of physical activity, body posture and sleep quality on the reproducibility of continuous ambulatory blood pressure monitoring. METHODS: Measurements were performed in 35 subjects (18 hypertensive, 11 male), mean +/- standard deviation age 49 +/- 13 years. Blood pressure (BP) was measured in the brachial artery, and beat-to-beat values of systolic blood pressure (SBP), diastolic blood pressure (DBP), mean arterial pressure and heart rate (HR) were computed. Physical activity and posture were continuously measured with five accelerometers. Subjective quality of sleep was assessed with a questionnaire. Reproducibility was expressed as an intraclass correlation coefficient and as the standard deviation of the within-subject differences. RESULTS: Posture and activity significantly influenced BP and HR. From lying to sitting, the SBP, DBP and HR increased 6 mmHg, 8 mmHg and 8 beats/min, respectively. From sitting to standing these respective increases were 4 mmHg, 2 mmHg and 13 beats/min. A further rise in activity (from standing to moving generally or walking) increased the SBP by 7 mmHg and the HR by 7 beats/min, and decreased the DBP by 8 mmHg. For daytime SBP, DBP and HR, the intraclass correlation coefficient (standard deviation of the within-subject differences) values were 0.93 (7.2 mmHg), 0.94 (3.8 mmHg) and 0.90 (4.1 beats/min). For night-time these respective values were 0.98 (4.4 mmHg), 0.97 (2.5 mmHg) and 0.96 (2.2 beats/min). Correction for physical activity level and posture hardly improved the reproducibility of daytime BP and HR. Reproducibility of night-time BP and HR was not improved by correction for physical activity, supine position or self-reported sleep quality. CONCLUSIONS: Within-subject differences between ambulatory BP recordings cannot be explained by differences in physical activity and body posture.     

The prospective, randomized investigation of the safety and efficacy of telmisartan versus ramipril using ambulatory blood pressure monitoring (PRISMA I)

OBJECTIVE: To compare the efficacy and safety of once-daily telmisartan and ramipril on blood pressure (BP) reductions during the last 6 h of the dosing interval. PATIENTS AND METHODS: In a prospective, randomized, open-label, blinded-endpoint study using ambulatory BP monitoring, 801 patients with mild-to-moderate hypertension were randomly assigned to once-daily treatment with telmisartan 80 mg for 14 weeks or ramipril 5 mg for 8 weeks and then force titrated to ramipril 10 mg for the last 6 weeks. Primary endpoints were the reduction from baseline in the last 6-h mean ambulatory systolic BP (SBP) and diastolic BP (DBP). Secondary endpoints included changes in 24-h, morning, daytime and night-time mean ambulatory BP and ambulatory BP response rates. RESULTS: Telmisartan 80 mg produced greater reductions in the last 6-h mean ambulatory SBP and DBP compared with ramipril 5 mg (P < 0.0001) and 10 mg (P < 0.0001), and was superior to ramipril for all secondary ambulatory SBP and DBP endpoints (P < 0.05). Ambulatory BP response rates (24-h mean ambulatory SBP/DBP < 130/80 mmHg or reduction from baseline > or = 10 mmHg) were greater with telmisartan 80 mg (P < 0.01) than with ramipril 5 and 10 mg. Ramipril was associated with a higher incidence of treatment-related cough (5.7 versus 0.5% for telmisartan). CONCLUSIONS: Telmisartan was significantly more effective than ramipril in reducing BP throughout the 24-h dosing interval and particularly during the last 6 h, a time when patients appear to be at greatest risk of cerebro- and cardiovascular events. Both drugs were well tolerated, although ramipril was associated with a higher incidence of cough.