Reproducibility of blood pressure dipping: Relation to day-to-day variability in sleep quality

Previous studies of the reproducibility of blood pressure (BP) dipping have yielded inconsistent results. Few have examined factors that may influence day-to-day differences in dipping. Ambulatory BP monitoring was performed on three occasions, approximately 1 week apart, in 115 untreated adult subjects with elevated clinic BPs. The mean ± standard deviation BP dip was 18 ± 7/15 ± 5 mm Hg (sleep/awake BP ratio = 0.87 ± 0.05/0.82 ± 0.06), with a median (interquartile range) day-to-day variation of 5.2 (3.1–8.1)/4.3 (2.8–5.6) mm Hg. There was no decrease in variability with successive measurements. The reproducibility coefficient (5.6 [95% confidence interval, 5.1–6.1] mm Hg) was greater and the intraclass correlation coefficient (0.53 [95% confidence interval, 0.42–0.63]) was smaller for the systolic dip than for 24-hour or awake systolic BPs, suggesting greater day-to-day variability in dipping. Variability in systolic dipping was greater in subjects with higher awake BP, but was not related to age, gender, race, or body mass index. Within individuals, day-to-day variations in dipping were related to variations in the fragmentation index (P < .001), a measure of sleep quality. Although mean 24-hour and awake BPs were relatively stable over repeated monitoring days, our study confirms substantial variability in BP dipping. Day-to-day differences in dipping are related to sleep quality.     

Association between sleep disorders and morning blood pressure in hypertensive patients

Sleep disorders are known to increase the risk of hypertension, yet few studies have investigated the relation between sleep disorders and morning blood pressure (BP). This study aimed to determine, whether the morning BP is associated with sleep quality and sleep-disordered breathing. A total of 144 hypertensive patients were included in this cross-sectional study. Each subject underwent anthropometric measurements, biochemical testing, 24-h ambulatory BP monitoring, and polysomnography (PSG). Sleep quality and sleep-disordered breathing were determined by PSG parameters of sleep architecture and sleep respiratory. There were no significant differences between subjects with and without morning hypertension in the parameters of sleep architecture and sleep respiratory. In multiple regression analysis, morning BP was independently associated with night-time BP and morning BP surge, but not with the parameters of sleep architecture and sleep respiratory. Further analysis showed that both night-time BP and morning BP surge were independently associated with the sleep respiratory parameters. In conclusion, sleep-disordered breathing might indirectly affect the morning BP by elevated night-time BP, yet neither poor sleep quality nor sleep-disordered breathing was major determinants of elevated morning BP in hypertensive patients.     

Sleep quality and blood pressure dipping in obstructive sleep apnea

Background:Obstructive sleep apnea (OSA) is associated with poor sleep quality and a high incidence of nondipping. The aim of this study was to determine the association of sleep quality and nocturnal blood pressure (BP) dipping in an OSA population.Methods:A total of 44 untreated subjects with mild to severe OSA underwent overnight-attended polysomnography and 24-h ambulatory BP monitoring. Subjects were off antihypertensive medication. The percentage of slow wave sleep, percentage of time awake after sleep onset during the sleep period, sleep efficiency, and arousal index were chosen as measurements of sleep quality. Dipping was evaluated using the change in systolic BP, diastolic BP, and mean arterial pressure. Patients were classified as dippers and nondippers based on a nocturnal drop in mean arterial pressure > 10%. Differences between groups were evaluated by independent sample t tests. Pearson correlation and linear regression were used to evaluate the association of sleep quality and dipping.Results:There were no differences between dippers and nondippers with regard to body mass index, age, or respiratory disturbance index. A total of 84% were nondippers. No difference was found between dippers and nondippers in sleep quality. None of the sleep quality measures correlated with the measurements of dipping. In multiple regression analyses, the percentage of slow wave sleep and arousal index each independently predicted only a small percentage of the variance (approximately 10%) of nocturnal DBP dipping.Conclusions:The prevalence of nondipping was very high in a population of untreated patients with mild to severe OSA. Nonetheless, sleep quality did not appear to be related to BP dipping.     

阻塞性睡眠呼吸暂停对动态血压影响的研究

目的　探讨阻塞性睡眠呼吸暂停 (OSA)夜间低氧血症对动态血压变化的影响。方法　选择阻塞性睡眠呼吸暂停综合征 (OSAS)患者 60例和正常对照组 2 0例进行多导睡眠图检查和 2 4h血压监测。结果　轻度OSAS患者的动态血压及其昼夜节律的改变与正常对照组相比无显著性差异 ;中度OSAS患者的nMDP及血压昼夜节律与正常对照组相比已有显著性差异 ;而重度OSAS组的动态血压改变则更加明显 ,2 4hMDP、2 4hMAP、dMSP、dMDP、dMAP、nMSP、nMDP、nMAP均明显高于对照组 ,其中 2 4hMDP、dMDP、dMAP、nMSP、nMDP与轻、中度组比较有显著性差异 ,同时夜间血压下降节律紊乱 ,昼夜血压差值减小。OSAS患者 2 4hMDP、dMDP、nMSP、nMDP、nMAP与睡眠呼吸暂停低通气指数 (AHI)呈显著正相关 ,而 2 4hMSP、2 4hMAP、nMSP、nMAP、ΔSBP、ΔDBP与睡眠中经皮血氧饱和度(SpO2 )降低大于 0 0 4的总次数、SpO2 低于 0 90的时间均呈正相关 ,而与睡眠中SpO2 最低值、SpO2 平均值呈负相关。结论　OSAS患者各期血压的平均水平与AHI、呼吸暂停持续时间及SpO2 降低的程度显著相关 ,OSAS的病情越重 ,这种血压变化及昼夜节律改变越显著     

阻塞性睡眠呼吸暂停低通气综合征患者血浆神经肽Y水平与睡前及晨起血压的相关性

目的 探讨阻塞性睡眠呼吸暂停低通气综合征(OSAHS)患者血浆神经肽Y(NPY)浓度与患者睡前及晨起血压水平的相关性.方法 分组:肥胖OSAHS患者32例(OSAHS组)、非OSAHS肥胖者26例(单纯肥胖组)和体质量正常的健康成人27名(正常对照组).其中OSAHS组和单纯肥胖组接受多导睡眠仪(PSG)监测.血浆NPY的浓度采用酶联免疫吸附试验(ELISA)法测定.结果 OSAHS组血浆NPY浓度显著高于单纯肥胖组(P＜0.05)及正常对照组(P＜0.01).OSAHS患者睡前舒张压、晨起收缩压及舒张压比单纯肥胖组明显升高,差异有统计学意义.相关分析显示,OSAH S组血浆NPY浓度与患者睡前舒张压、晨起收缩压及舒张压呈正相关(P值分别为0.049、0.017、0.006).结论 OSAHS组NPY水平升高,NPY对OSAHS患者血压尤其晨起血压升高起到一定促进作用.     

Mechanisms of pulse pressure amplification dipping pattern during sleep time: the SAFAR study

The difference in pulse pressure (PP) between peripheral arteries and the aorta, called pulse pressure amplification (PPamp), is a well-described physiological phenomenon independently associated with cardiovascular events. Recent studies suggest that it exhibits circadian variability. Our aim was to detect the factors associated with the circadian variability of PPamp. In 497 consecutive subjects (aged 54 years, 56.7% male, 79.7% hypertensives), we assessed the circadian pattern of peripheral and central arterial hemodynamics by 24-hour evaluation of brachial and aortic blood pressure (BP), augmentation index (AI), and pulse wave velocity (PWV) using a validated oscillometric device (Mobil-O-Graph). All parameters exhibited a circadian variation. Sleep dipping (decrease) pattern was observed for PPamp, brachial and aortic systolic BP, mean BP, and PWV, whereas a rising pattern (higher sleep than wake values) was observed for brachial PP, aortic PP, and AI. The factors independently associated with the less sleep dipping in PPamp were older age, lower height, the use of antihypertensive medication, and sleep decrease in arterial stiffness (PWV), whereas female gender, the presence of hypertension, sleep increase of pressure wave reflections (AI), sleep decrease in heart rate, and mean BP were associated with a greater sleep-dipping in PPamp. These data provide further pathophysiological understanding of the mechanisms leading to PPamp dipping. Several implications regarding the clinical use of the aortic and brachial BP, especially during sleep time, are raised that should be addressed in future research.     

Stress, menopausal status and nocturnal blood pressure dipping patterns among hypertensive women

BACKGROUND:

A less than 10% decline in blood pressure during the night is known as a nondipping blood pressure (BP) pattern. Nondipping BP has been shown to be associated with target organ damage and poorer cardiovascular outcomes. Additionally, some evidence suggests that hypertensive nondipping women are at greater risk for target organ damage than hypertensive nondipping men.

OBJECTIVE:

To determine whether stress, demographics, menopausal status or sleep quality are associated with nondipping BP among hypertensive women.

METHODS:

A cross-sectional study design was used to describe the relationship between stress and dipping status among a sample of hypertensive women and to describe the sample by age, ethnicity, marital status, menopausal status, current medications and sleep quality.

RESULTS:

The study sample consisted of 47 women (mean [± SD] age 57±13.9 years) with essential or office hypertension who underwent 24 h ambulatory BP monitoring, and completed stress and sleep quality measurements. Thirty-one women (66%) were classified as dippers and 16 (34%) were classified as nondippers. Nondippers were older (P=0.04), postmenopausal (P=0.003) and had lower stress scores (P=0.02) than their dipper counterparts. Postmenopausal status significantly predicted nondipping (OR 16; 95% CI 1.9 to 136.4).

CONCLUSION:

These findings were of interest given that some women had a nondipping BP pattern and significantly lower stress scores. It is possible that there are fundamentally different physiological mechanisms that explain this nondipping phenomenon. In the future, the identification of specific hemodynamic mechanisms associated with nondipping could potentially influence the choice of antihypertensive treatment regimens for nondipper hypertensive patients.     

高血压合并阻塞性睡眠呼吸暂停综合征患者昼夜血压的变化

目的研究轻中度高血压合并阻塞性睡眠呼吸暂停综合征(OSAS)患者昼夜血压变化的特点。方法入选心功能(NHYA)Ⅰ级的轻中度高血压患者177例,经多导睡眠呼吸监测后,按睡眠呼吸暂停指数分为4组,单纯高血压组(A组)42例,高血压合并轻度OSAS组(B组)66例,高血压合并中度OSAS组(C组)25例和高血压合并重度OSAS组(D组)44例,进行24 h动态血压监测。结果 D组患者昼间和夜间血压水平明显高于A组(P<0.05,P<0.01),与A组比较,B、C和D组夜间舒张压显著升高(P<0.05,P<0.01)。夜间低血氧水平与醒时、醒后舒张压、昼间、夜间收缩压和舒张压呈负相关(P<0.05)。结论轻中度高血压合并OSAS患者的夜间舒张压更高,合并重度OSAS的高血压患者全天血压水平均明显高于单纯高血压患者,血压升高幅度与夜间低氧血症程度呈负相关。     

老年高血压病并发阻塞性睡眠呼吸暂停综合征患者血压特点及与炎症因子的关系

目的研究并发中重度阻塞性睡眠呼吸暂停综合征（obstructive sleep apnea syndrome,OSAS）的老年高血压患者血压的变化情况及炎症因子的水平,从而揭示此类患者的疾病特点。方法将60例年龄大于60岁的研究对象根据诊所血压、24 h动态血压和多导睡眠图监测结果分为单纯高血压病组（n=30）和并发OSAS组（高血压病并发中重度睡眠呼吸暂停综合征,n=30）。用ELISA法测定白介素-6（IL-6）、sCD40L、超敏C反应蛋白（hs-CRP）、可溶性细胞间黏附分子1（ICAM-1）及血管细胞黏附分子1（VCAM-1）的浓度。结果①并发OSAS组中非杓型血压的发生率为67%,明显高于单纯高血压组的发生率37%（P<0.05）。②并发OSAS组24 h、白天、夜间平均脉压（mean arterial blood pressure,MAP）分别为（51±13）mmHg（1 mmHg=0.133 kPa）,（50±13）mmHg和（51±17）mmHg均明显高于单纯高血压组（45±7）mmHg,（46±8）mmHg和（44±6）mmHg,并有统计学意义（P<0.05）。③并发OSAS组的IL-6、sCD40L、hs-CRP、ICAM-1、VCAM-1浓度明显高于单纯高血压组。④并发OSAS组的hs-CRP、ICAM-1、VCAM-1浓度变化与呼吸紊乱指数、睡眠血氧下降程度正相关（r=0.852,P<0.05）。hs-CRP与MAP呈正相关（P<0.01）,ICAM-1与夜间血压下降率呈负相关（P<0.05）。结论中重度睡眠呼吸暂停影响老年人血压昼夜节律的变化,同时对脉压产生明显影响,炎症反应也明显加重。     

老年高血压合并阻塞性睡眠呼吸暂停综合征患者血压昼夜节律的特点

目的探讨老年高血压合并阻塞性睡眠呼吸暂停综合征(OSAS)患者血压昼夜节律的特点。方法入选老年原发性高血压患者90例,根据多导睡眠监测结果,将受试者分为单纯高血压组(42例)、高血压合并轻度OSAS组(21例)、高血压合并中、重度OSAS组(27例),行24 h动态血压监测,观察睡眠呼吸状态对血压昼夜节律的影响。结果高血压合并轻度OSAS组、高血压合并中、重度OSAS组与单纯高血压组比较,夜间收缩压、舒张压差异有显著性意义(P<0.05);与单纯高血压组比较,高血压合并轻度OSAS组血压曲线非杓型所占比例差异有显著性意义(P<0.05),高血压合并中、重度OSAS组比例有显著性差异(P<0.01);高血压合并中、重度OSAS组与高血压合并轻度OSAS组比较血压非杓型所占比例差异有显著性意义(P<0.05)。结论老年高血压合并OSAS患者其血压变异高于单纯高血压患者,这在合并有中、重度OSAS的患者表现尤其明显,因此老年高血压患者要注意睡眠状态时血压的变化,早期诊断OSAS并积极有效地治疗。     

高血压合并阻塞性睡眠呼吸暂停综合征的动态血压分析

目的分析高血压合并阻塞性睡眠呼吸暂停综合征（obstructive sleep apnea syndrome,OSAS）患者24小时动态血压（ambulatory blood pressum,ABP）的特点。方法80例高血压患者行多导睡眠仪（polysomnography）,行动态血压监测,按监测结果分为单纯高血压病组（essentialhypertention,EH）、EH合并轻度OSAS组、EH合并中重度OSAS组。3组进行日间、夜间平均收缩压;日间、夜间平均舒张压;非杓型高血压发生率的对比。结果EH合并OSAS组（轻度及中重度）夜间平均收缩压、平均舒张压较EH组患者升高,EH合并中重OSAS组日间平均收缩压较EH组患者升高,均有统计学差异。EH合并OSAS组较EH组相比非杓型高血压发生率升高,有统计学差异;EH合并中重度OSAS组升高明显。结论OSAS与高血压有很强的相关性,EH合并OSAS患者非杓型高血压发生率高于单纯EH组。     

Sleep, blood pressure and obesity in 22,389 New Zealanders

Aim: To determine the relationship of sleep disorders with blood pressure and obesity in a large, relatively healthy, community‐based cohort. Methods: A cross‐sectional study was undertaken using data from 22 389 volunteer blood donors in New Zealand aged 16–84 years. Height, weight, neck circumference and blood pressure were measured directly, and data on sleep and other factors were ascertained using a validated self‐administered questionnaire. Results: Even in a relatively young, non‐clinical cohort, lack of sleep (34%), snoring (33%), high blood pressure (20%) and obesity (19%) are common. After adjusting for relevant confounders, participants at high risk of sleep apnoea had double the odds of having high blood pressure but only in participants over 40 years. Very low and high quantities of sleep are also associated with high blood pressure. Even after controlling for neck circumference, self‐reported sleep apnoea, sleep dissatisfaction and low amounts of sleep are associated with a higher body mass index. Conclusions: Obesity and hypertension have significant associations with a variety of sleep disorders, even in those less than 40 years of age and after adjusting for a wide range of potential confounders.     

康复治疗对老年脑梗死急性期睡眠障碍患者动态血压的影响

目的探讨康复治疗对老年脑梗死急性期睡眠障碍患者动态血压的影响。方法选择265例老年脑梗死急性期患者进行匹兹堡睡眠质量指数量表(PSQI)评分,将其分为睡眠障碍组(PSQI评分>7分)167例和非睡眠障碍组(PSQI评分≤7分)98例,同时给予2组患者康复治疗,观察2组患者治疗前、后动态血压参数变化的情况及睡眠障碍组患者经康复治疗后PSQI评分的变化。结果睡眠障碍组患者康复治疗后,睡眠质量、入睡时间、睡眠时间、睡眠效率、昼间功能与康复前比较有显著改善,差异有统计学意义(P<0.01)。2组患者康复治疗2周后,睡眠障碍组患者的24 h平均收缩压和舒张压、昼间平均舒张压、夜间平均收缩压和舒张压、24 h脉压、晨起收缩压和舒张压下降幅度与非睡眠障碍组患者比较差异有统计学意义(P<0.05),而2组患者昼间平均收缩压、昼间收缩压和舒张压变异、夜间收缩压和舒张压变异比较差异无统计学意义(P>0.05)。结论康复治疗对改善患者睡眠质量,恢复老年脑梗死患者正常的血压昼夜节律具有重要意义。     

Acute effects of night-time noise exposure on blood pressure in populations living near airports.

AIMS: Within the framework of the HYENA (hypertension and exposure to noise near airports) project we investigated the effect of short-term changes of transportation or indoor noise levels on blood pressure (BP) and heart rate (HR) during night-time sleep in 140 subjects living near four major European airports. METHODS AND RESULTS: Non-invasive ambulatory BP measurements at 15 min intervals were performed. Noise was measured during the night sleeping period and recorded digitally for the identification of the source of a noise event. Exposure variables included equivalent noise level over 1 and 15 min and presence/absence of event (with LAmax > 35 dB) before each BP measurement. Random effects models for repeated measurements were applied. An increase in BP (6.2 mmHg (0.63-12) for systolic and 7.4 mmHg (3.1, 12) for diastolic) was observed over 15 min intervals in which an aircraft event occurred. A non-significant increase in HR was also observed (by 5.4 b.p.m.). Less consistent effects were observed on HR. When the actual maximum noise level of an event was assessed there were no systematic differences in the effects according to the noise source. CONCLUSION: Effects of noise exposure on elevated subsequent BP measurements were clearly shown. The effect size of the noise level appears to be independent of the noise source.     

Gender-specific associations of sleep duration with uncontrolled blood pressure in middle-aged patients

Objective: The present study was designed to evaluate the associations between sleep duration and uncontrolled blood pressure in a hospital-based sample of middle-aged adults. Methods: Between March 2012 and December 2012, a cross-sectional survey was conducted among the hypertensive outpatients of Anzhen Hospital and a community hospital in Beijing, China. Eligible participants were adults aged 35–55 years with an established diagnosis of hypertension and had been on standard antihypertensive drug treatment for at least 6 months. An interviewer-led questionnaire was used to collect the participants’ demographic, lifestyle and dietary information, as well as medical histories. Usual sleep durations were categorized as <7?h, 7–8?h and >8?h per night. Logistic regression models were used to assess gender-specific associations between sleep duration and uncontrolled hypertension, with adjustment for age, gender, family history, diabetes, smoking, alcohol consumption and physical activity. Results: A total of 3038 participants were finally investigated. Among them, 1569 (51.6%) patients had their blood pressure uncontrolled. In men, no significant association was found between sleep duration categories and uncontrolled hypertension. In women, compared with those sleeping <7?h, longer sleepers tended to have a lower risk of uncontrolled hypertension for sleeping 7–8 hours (odds ratio [OR] 0.537, 95% confidence interval [CI], 0.370–0.780) and sleeping >8?h (OR 0.316, 95% CI, 0.202–0.494), respectively. Conclusion: Modest associations between short sleep duration and uncontrolled hypertension were seen in middle-aged women but not in men in the hypertensive population.     

Ethnic differences in the association of birth weight and blood pressure: the Georgia cardiovascular twin study

BACKGROUND: African Americans (AAs) not only have higher blood-pressure levels, but also an increased risk of low weight at birth, compared with European Americans (EAs). In light of fetal programming theories, it has been suggested that ethnic differences in blood pressure originate in utero. However, most previous studies in biethnic samples have not found a significant inverse association between birth weight and blood pressure in AAs. METHODS: In 562 EA and 465 AA adolescent twins of the Georgia Cardiovascular Twin Study, we investigated the potential ethnic difference in the association of blood pressure and birth weight, with the ability to control for potential confounding by familial factors. RESULTS: Blood-pressure levels were significantly higher in AAs compared to EAs, independent of birth weight (P < .01). After adjustment for parental factors and body mass index, the difference in systolic blood pressure per kg birth weight was -1.1 mm Hg (95% confidence interval, -2.7 to 0.48, P = .17) in EAs, and -2.5 mm Hg (95% confidence interval, -4.7 to -0.40, P = .02) in AAs. A significant ethnic interaction was revealed in paired analysis, where the inverse association remained in AAs, but not in EAs. Associations with diastolic blood pressure were generally weaker and nonsignificant. CONCLUSIONS: We showed that low birth weight was associated with an elevated systolic blood pressure in AAs, independent of familial factors. The results also suggest that the association between birth weight and blood pressure may be more pronounced in AAs in adolescence.     

阻塞性睡眠呼吸暂停综合征患者血尿酸凌晨血压的研究

目的探讨不同程度阻塞性睡眠呼吸暂停低通气综合征(OSAHS)患者血尿酸、凌晨血压的变化。方法根据呼吸暂停低通气指数(AHI)将2006年4月至2007年6月在贵州省人民医院呼吸内科确诊OSAHS的134例患者分为轻、中及重度3组,同时选择23名健康正常者作为对照组,测定血尿酸及凌晨血压值。结果血尿酸值在OSAHS轻、中、重度组患者及对照组分别为(392.10±88.22)μmol/L、(460.14±118.86)μmol/L、(537.63±134.11)μmol/L、(304.36±80.12)μmol/L,四组比较差异统计学意义;OSAHS重度组与其余三组、OSAHS中度组与对照组的血压值比较,差异有统计学意义。结论OSAHS患者血清尿酸随阻塞程度增加而升高,血压出现紊乱,血尿酸升高可能为血压异常的部分原因。