Nocturnal blood pressure in untreated essential hypertensives

AIM. Prevalence, correlates and reproducibility of nocturnal hypertension (NH) as defined by fixed cut-off limits in uncomplicated essential hypertension are poorly defined. Therefore, we assessed such issue in a cohort of 658 untreated hypertensives. METHODS. All subjects underwent procedures including cardiac and carotid ultrasonography, 24-h urine collection for microalbuminuria, ambulatory blood pressure monitoring (ABPM), over two 24-h periods within 4 weeks. NH was defined according to current guidelines (i.e. night-time blood pressure, BP ? 120/70 mmHg) and non-dipping status as a reduction in average systolic (SBP) and diastolic BP (DBP) at night lower than 10% compared with daytime values. RESULTS. A total of 477 subjects showed NH during the first and second ABPM period; 62 subjects had normal nocturnal BP (NN) in both ABPM sessions. Finally, 119 subjects changed their pattern from one ABPM session to the other. Overall, 72.5% of subjects had reproducible NH, 18% variable pattern (VP) and 9.5% reproducible NN. In the same group, figures of reproducible non-dipping, variable dipping and reproducible dipping pattern were 24%, 24% and 52%, respectively. Among NH patients, 56% of whom were dippers, subclinical cardiac organ damage was more pronounced than in their NN counterparts. CONCLUSIONS. In uncomplicated essential hypertensives, NH is a more frequent pattern than non-dipping; NH is associated with organ damage, independently of dipping/non-dipping status. This suggests that options aimed at restoring a blunted nocturnal BP fall may be insufficient to prevent cardiovascular complications unless night-time BP values are fully normalized.     

高血压病患者动态脉压与颈动脉粥样硬化的相关性

目的探讨高血压病患者24h动态脉压与颈动脉粥样硬化的相关性。方法选择1级和2级高血压患者120例作为研究对象,32位健康人做对照。对所有患者进行动态血压监测,做颈动脉血管超声测量颈总动脉内膜-中层厚度、颈总动脉内径,局限性的内膜-中层厚度≥1.3mm定为斑块。结果高血压患者24h脉压值、白昼脉压均值、夜间脉压均值均较对照组明显增高,2级高血压患者脉压大于1级高血压病组,高血压患者内膜-中层厚度明显增厚,且随着斑块严重程度的增加,厚度逐渐增厚;直线相关分析显示,脉压尤其是夜间脉压与内膜-中层厚度及斑块呈明显正相关,内膜-中层厚度与斑块呈正相关。结论颈动脉内膜-中层厚度是动脉粥样硬化的早期表现,脉压尤其是夜间脉压是反应早期动脉硬化一个简便而实用的指标。     

Potassium supplementation lowers blood pressure and increases urinary kallikrein in essential hypertensives

In order to eludicate possible mechanism(s) involved in the blood pressure reduction induced by potassium (K) supplementation, we studied the changes of BP and of some of its regulatory systems, including levels of urinary kallikrein (UKal)--an index of renal kallikrein production. Twenty-four untreated essential hypertensives, with a basal BP of 147/96 +/- 13/7 mmHg and normal renal function, received in crossover, double-blind, randomised fashion, 64 mmol KCl or placebo during two periods of 4 weeks each. At the 4th week of potassium supplementation systolic, diastolic and mean BPs decreased by 6.3 +/- 2 (P less than 0.01), 3.0 +/- 2 and 4.1 +/- 2 (P less than 0.05) mmHg respectively for the supine position, and 5.0 +/- 2, 4.0 +/- 2 (P less than 0.05) and 4.0 +/- 1 (P less than 0.05) mmHg for the standing position. Urinary potassium (K) increased from 55 +/- 4 to 123 +/- 6 mmol/24 hours (P less than 0.001) and UKal from 692 +/- 69 to 1052 +/- 141 mU/24 hours (P less than 0.01). Serum K rose from 3.8 +/- 0.1 mEq/l to 4.1 +/- 0.1 mmol/l (P less than 0.001) and PRA from 0.77 +/- 0.12 to 0.99 +/- 0.14 ng/ml/h (P less than 0.05). Correlations were observed between UKal and urinary K (r = 0.44, P less than 0.0001); between differences in UKal and urinary K and in UKal and urinary Na (r = 0.50, P less than 0.0005 and r = 0.48, P less than 0.001 respectively).(ABSTRACT TRUNCATED AT 250 WORDS)     

非重症自发性脑出血急性期血压与近期预后的关系

目的探讨非重症自发性脑出血急性期血压与近期预后的关系。方法选择168例经头颅CT证实的非重症自发性脑出血患者起病后72 h内的血压情况,应用改良的Rankin量表(mRS)对患者第21天神经功能恢复情况进行评分并分组,mRS≥4分组(64例)和mRS4分组(104例),并进行回归分析。结果与mRS4分组比较,mRS≥4分组患者急性期收缩压、舒张压、平均动脉压(MAP)均明显升高,差异有统计学意义(P0.05)。与MAP≤120 mm Hg(1 mm Hg=0.1 33 kPa)患者比较,MAP120 mm Hg患者预后明显差(OR=2.593,95% CI:1.324～5.078,P=0.005)。MAP是近期预后差的独立危险因素(OR=1.025,95% CI:1.007～1.044,P=0.008)。结论非重症自发性脑出血急性期血压与近期预后密切相关,MAP升高是近期预后差的独立危险因素之一。     

Inverse relationship between heart rate and blood pressure variabilities in rats

The interplay of heart rate variability, baroreceptor control of heart rate, and blood pressure (BP) variability was examined in chronically instrumented, unanesthetized, freely moving rats in which the efferent neural influences on heart rate were pharmacologically altered. In each rat, BP was recorded continuously for 90 minutes in the control condition and in one or more of the following conditions: 1) beta-adrenergic receptor blockade by propranolol, 1 mg/kg; 2) cholinergic blockade by atropine, 0.75 mg/kg, and 3) combined blockade by propranolol plus atropine. Each BP recording was analyzed beat-to-beat by a computer that calculated heart rate and BP variabilities, both expressed as variation coefficients. In addition, under each condition the sensitivity of the arterial baroreceptor control of heart rate was assessed by measuring the reflex changes in pulse interval in response to BP changes induced by bolus i.v. injections of phenylephrine and nitroprusside. As compared with the control condition, 1) propranolol (n = 10) reduced heart rate variability by 23 +/- 4% (p less than 0.01), only slightly impaired baroreceptor reflex sensitivity, and did not significantly modify BP variability (+11 +/- 7%); 2) atropine (n = 11) reduced heart rate variability by 30 +/- 7% (p less than 0.01), drastically impaired baroreceptor reflex sensitivity, and increased BP variability (+40 +/- 8%, p less than 0.01); 3) combined blockade (n = 10) caused variability and baroreceptor reflex changes similar to those induced by atropine alone. Thus, heart rate variability depends on both vagal and sympathetic influences. However, only the former component affects BP variability, that is, it plays an antioscillatory role.(ABSTRACT TRUNCATED AT 250 WORDS)     

J-shaped relation between blood pressure and stroke in treated hypertensives

The objective of this study was to investigate the relationship between hypertension and risk of stroke in the elderly. The study was performed within the framework of the Rotterdam Study, a prospective population-based cohort study. The risk of first-ever stroke was associated with hypertension (relative risk, 1.6; 95% CI, 1.2 to 2.0) and with isolated systolic hypertension (relative risk, 1.7; 95% CI, 1.1 to 2.6). We found a continuous increase in stroke incidence with increasing blood pressure in nontreated subjects. In treated subjects, we found a J-shaped relation between blood pressure and the risk of stroke. In the lowest category of diastolic blood pressure, the increase of stroke risk was statistically significant compared with the reference category. Hypertension and isolated systolic hypertension are strong risk factors for stroke in the elderly. The increased stroke risk in the lowest stratum of blood pressure in treated hypertensive patients may indicate that the therapeutic goal of "the lower the better" is not the optimal strategy in the elderly.     

原发性高血压患者动态血压与微量白蛋白尿的关系

目的：研究原发性高血压患动态血压与微量白蛋白尿之间的关系。方法：（1）用放免法测定99例高血压患的尿微量白蛋白，根据有无尿微量白蛋白将高血压患分为微量白蛋白尿组和无微量白蛋白尿组；（2）所有研究对象均进行24小时动态血压监测。结果：微量白蛋白尿组与无微量白蛋白尿组相比，其收缩压明显升高，脉压明显增大（P＜0．01）。结论：收缩压升高、脉压增大可能与高血压早期肾脏损害有关。     

原发性高血压患者胰岛素抵抗与非高密度脂蛋白胆固醇的关系

目的探讨壮族原发性高血压患者胰岛素抵抗(IR)与非HDL-C的关系,为壮族高血压综合治疗提供参考。方法选取壮族高血压患者200例,以是否合并糖尿病分为合并组80例和未合并组120例;另选健康体检者60例为对照组。各组均测定TC、TG、LDL-C、HDL-C、空腹血糖和空腹胰岛素,计算IR指数(HOMA-IR)和非HDL-C,分析非HDL-C与IR等指标的关系。以非HDL-C水平进行四分位,分为上四分位组51例和下四分位组48例,并分析HOMA IR等指标间的关系。结果与对照组比较,合并组和未合并组患者空腹血糖、空腹胰岛素、TC、TG、IDL C、非HDL C和HOMA IR明显升高,HDLC明显降低(P<0.05,P<0.01);与未合并组比较,合并组患者空腹胰岛素、非HDL-C和HOMA IR明显升高,HDLC明显降低(P<0.05)。与下四分位组比较,上四分位组患者收缩压、舒张压、空腹血糖、TC、TG、LDL-C和HOMA-IR明显升高,HDL-C明显降低(P<0.05,P<0.01)。结论不同糖代谢状态下壮族高血压患者均存在脂代谢紊乱和IR。非HDL-C与IR密切相关,是临床上评估糖、脂代谢异常的良好指标。     

原发性高血压患者中的白大衣效应及其与血压变异性的相关性

目的 探讨原发性高血压患者中的白大衣效应的发生率及其与血压变异性的相关性.方法 1级、2级原发性高血压患者410例自愿参加本研究.受试者自测1周家庭血压,根据诊室血压与家庭血压情况进行分类:未治疗患者分为白大衣性高血压(n=38)和持续性高血压(n=66);已治疗患者分为已控制高血压(n=131)、白大衣未控制高血压(...     

减慢呼吸频率对原发性高血压患者心率变异性和血压变异性的影响

目的观察减慢呼吸频率对原发性高血压患者心率、血压和心率变异性(HRV)和血压变异性(BPV)的影响。方法对60例原发性高血压患者进行16次/分、8次/分的均匀呼吸调节,同步记录呼吸、心电、血压波形,测量记录每次呼吸调节后即刻血压、心率。观察减慢呼吸频率对原发性高血压患者血压、心率、呼吸峰的影响;并用常规方法和校正方法(校正呼吸峰移位)分析对HRV、BPV高频功率(HF)、低频功率(LF)、LF/HF的影响。结果与呼吸频率16次/分比较,8次/分使血压降低(P0.001),心率减慢(P0.001),HRV和BPV的呼吸峰左移(P0.001);按常规方法分析,与呼吸频率16次/分比较,8次/分时HRV和BPV的HF减小,LF和LF/HF增大(除BPV的HF改变外,P均0.001);校正呼吸峰移位影响后,与呼吸频率16次/分比较,8次/分时HRV和BPV的HF增大,LF和LF/HF减小(P均0.001)。结论减慢呼吸频率可使原发性高血压患者血压降低,心率减慢,其机制为减慢呼吸频率增加了患者迷走神经张力,有助交感-迷走平衡移向迷走神经。     

高血压病患者动态血压与动脉顺应性的相关性研究

目的:探讨高血压病患者动脉顺应性的变化,及其与动态血压监测(ABPM)各指标间的相互关系。方法:对262例高血压病患者和104例正常人进行动态血压监测(ABPM)和脉搏波速度(PWV)测定。结果:高血压组的颈动脉-桡动脉(G-R)PWV、颈动脉-股动脉(C-F)PWV,24 h、白昼及夜间平均血压,平均脉压,心率,血压负荷均显著高于正常对照组(P<0.05~<0.01)。C-F PWV及C-R PWV与24 h、白昼及夜间平均血压,心率,血压负荷均呈显著正相关(r=0.108~0.406,P<0.05~<0.001)。C-F PWV比C-R PWV与平均收缩压和收缩压负荷的相关性更强。C-F PWV与动态脉压、年龄显著正相关(r=0.205~0.406,P<0.001)。结论:动脉顺应性减退是高血压的重要改变,大动脉顺应性与动态脉压、收缩压和年龄的关系更为密切。     

Effect of short-term supplementation of potassium chloride and potassium citrate on blood pressure in hypertensives

Randomized trials have shown that increasing potassium intake lowers blood pressure. However, most previous trials used potassium chloride, whereas potassium in fruits and vegetables is not a chloride salt. It is unclear whether a nonchloride salt of potassium has a greater or lesser effect on blood pressure compared with potassium chloride. We performed a randomized crossover trial comparing potassium chloride with potassium citrate (96 mmol/d, each for 1 week) in 14 hypertensive individuals. At baseline, blood pressure was 151+/-16/93+/-7 mm Hg with a 24-hour urinary potassium of 81+/-24 mmol. During the randomized crossover part of the study, blood pressure was 140+/-12/88+/-7 mm Hg with potassium chloride (24-hour urinary potassium: 164+/-36 mmol) and 138+/-12/88+/-6 mm Hg with potassium citrate (24-hour urinary potassium: 160+/-33 mmol). These blood pressures were significantly lower compared with that at baseline; however, there was no significant difference in blood pressure between potassium chloride and potassium citrate, mean difference (95% confidence interval): 1.6 (-2.3 to 5.6) mm Hg for systolic and 0.6 (-2.4 to 3.7) mm Hg for diastolic. Our results, in conjunction with the evidence from many previous trials that potassium chloride has a significant blood pressure-lowering effect, suggest that potassium citrate has a similar effect on blood pressure as potassium chloride. These results support other evidence for an increase in potassium intake and indicate that potassium does not need to be given in the form of chloride to lower blood pressure. Increasing the consumption of foods high in potassium is likely to have the same effect on blood pressure as potassium chloride.     

老年男性原发性高血压患者动态血压及血压变异性与踝臂指数的关系探讨

目的评价老年男性原发性高血压患者动态血压及血压变异性(BPV)与踝臂指数(ABI)的关系。方法入选老年男性原发性高血压患者160例,按照ABI分为正常ABI组(ABI>0.90)104例和低ABI组(ABI≤0.90)56例,比较并分析其24 h动态血压参数和BPV参数。结果低ABI组较正常ABI组24 h平均脉压[(62.4±13.8)mm Hg比(53.0±13.0)mm Hg]、日间平均脉压[(67.3±17.0)mm Hg比(55.4±20.0)mm Hg]和夜间平均脉压[(63.0±16.0)mm Hg比(52.9±13.6)mm Hg]均高(P<0.01),同时夜间收缩压最大值[(146.5±17.4)mm Hg比(135.5±17.1)mm Hg]、夜间收缩压标准差[(12.4±4.0)mm Hg比(10.1±4.2)mm Hg]均大(P<0.05)。结论老年男性原发性高血压患者夜间收缩压最大值、夜间收缩压标准差、日间平均脉压、夜间平均脉压和24 h平均脉压升高可能是低ABI的危险因素。     

老年高血压患者亚临床甲状腺功能减退与血压变异性的关系

目的探讨亚临床甲状腺功能减退(亚甲减)的老年高血压患者每日血压变异性(BPV)指标特点及与亚甲减的关系。方法共纳入260例老年高血压患者,其中129例合并亚甲减,131例甲状腺功能正常者作对照,采集患者身高、体重、诊室坐位血压、血甲状腺功能指标、空腹血糖(FBG)、糖化血红蛋白、血脂、高敏C反应蛋白、血尿酸、同形半胱氨酸等指标,同时作24 h动态血压监测。结果亚甲减组与甲功正常组比较,夜间收缩压、清晨收缩压、反杓形节律构成比更高(P<0.05),杓形节律构成比、舒张压夜间下降率更低(P<0.05)。多元逐步回归分析显示:即便排除其他因素影响,清晨收缩压仍与游离三碘甲状腺原氨酸(FT3)负相关,与促甲状腺激素(TSH)正相关;清晨舒张压与年龄负相关,与体重、TSH正相关;夜间收缩压下降率与FBG负相关,与FT3正相关;夜间舒张压下降率与FT3正相关。结论老年高血压患者BPV增大与亚甲减密切相关。     

原发性高血压患者血压变异性与左心室质量指数的相关性分析

目的探讨原发性高血压患者血压变异性(blood pressure variability,BPV)与左心室质量指数(left ventricular mass index,LVMI)的相关性。方法选择我院住院的原发性高血压患者95例,根据心电图、彩色超声心动图检查确定是否伴有左心室肥厚(left ventricular hypertrophy,LVH)分为LVH组42例及无LVH组53例,另选择血压正常且无LVH的健康体检者40例为对照组,收集3组一般临床资料,检测同型半胱氨酸(Hcy)水平,进行24 h动态血压监测,比较3组24 h、夜间、昼间平均血压、收缩压标准差和舒张压标准差及LVMI。结果3组年龄、体质量指数、吸烟、尿酸、血红蛋白、血脂、糖化血红蛋白及各时间段内平均血压比较,差异无统计学意义(P>0.05);3组性别、糖尿病比例、Hcy、肌酐、LVMI及24 h、夜间、昼间收缩压标准差和舒张压标准差比较,差异有统计学意义(P<0.05,P<0.01)。LVH组男性比例、Hcy、LVMI及24 h、夜间、昼间收缩压标准差和舒张压标准差明显高于无LVH组和对照组(P<0.05),LVH组和无LVH组糖尿病比例和肌酐水平明显高于对照组,差异有统计学意义[59.5%和56.6%vs 7.5%,(92.0±4.8)μmol/L和(81.3±15.9)μmol/L vs(65.4±13.2)μmol/L,P<0.05]。无LVH组与对照组LVMI及24 h、夜间、昼间收缩压标准差和舒张压标准差比较,差异无统计学意义(P>0.01)。LVH组非杓型高血压比例明显高于无LVH组和对照组(85.7%vs 34.0%、5.0%,P=0.000)。结论BPV与高血压患者的LVH关系密切,其可能作为靶器官损伤最新的独立预测因素。     

原发性高血压患者血压变异性与早期肾功能损害的相关性研究

目的：观察原发性高血压（EH）患者血压变异性与尿微量白蛋白/尿肌酐比值的相关性。方法：随机选择60例EH患者作为EH组,按照24h平均动脉压均值高度又分为3个亚组,即EH1组（90.2～106.6mmHg）、EH2组（106.6～118.3mmHg）及EH3组（118.3～143.7mmHg）,各亚组均20例,另选择15例健康正常人作为健康对照组。监测所有研究对象在日间、夜间及24h收缩压变异性和舒张压变异性,以晨尿微量白蛋白/尿肌酐比值作为早期肾功能损害的指标,研究其相关性。结果：两组均存在血压变异性,与健康对照组比较,EH组日间、夜间及24h收缩压变异性[日间：（12.62±2.96）比（17.62±3.27）,夜间：（8.32±2.14）比（11.63±2.35）,24h：（11.23±2.25）比（18.35±2.94）]和舒张压变异性[日间：（10.32±2.41）比（12.48±2.85）,夜间：（9.52±2.00）比（11.59±3.12）,24h：（10.68±2.16）比（13.45±3.00）]均明显增大（P均〈0.01）。双变量相关分析显示EH组及EH各个亚组的日间、夜间及24h收缩压和舒张压的血压变异性均与尿微量白蛋白/尿肌酐比值均呈正相关（r=0.217～0.485,P〈0.05）。结论：原发性高血压患者血压变异性与早期肾脏损伤密切相关,改善血压变异性对预防早期肾功能损害有益。     

高血压病患者冠状动脉病变积分与血压变异性的关系

目的　探讨高血压病患者冠状动脉病变积分 (CAS)与血压变异性的关系。方法　选择 4 32例因拟诊冠心病而行冠状动脉造影的高血压病患者为研究对象 ,以标准 Judkins法行冠状动脉造影术 ,计算机定量分析系统 (QCA)分析冠状动脉狭窄程度并计算 CAS。同时行 2 4 h动态血压监测 (ABPM)。结果　性别、2 4 h收缩压标准差 (2 4 hSTDs)、2 4 h最大平均动脉压 (MAPmax)、升主动脉内径 (Ao)、高密度脂蛋白胆固醇 (HDL - C)均与 CAS有显著相关关系。经多因素 L ogistic回归分析显示 ,2 4 h STDs、Ao与 CAS呈显著正相关。结论　 2 4 h STDs、Ao与 CAS密切相关 ,是高血压病患者冠心病发生发展的良好的预测指标 ,并可应用于临床指导冠心病危险人群的早期干预。     

老年高血压的动态血压监测

目的探讨老年高血压患者的动态血压监测特点。方法使用美国ＡｃｕｕｔｒａｋｅｒⅡ型无创动态血压监测仪对６０例老年高血压患者及对照组进行２４小时动态血压监测，日间血压每２０分钟、夜间每４５分钟记录１次，对各种参数进行对比分析。结果２４小时、日间、夜间的收缩压、舒张压和血压负荷值等参数，老年对照组明显高于青中年对照组；老年高血压Ⅰ、Ⅱ、Ⅲ期各组明显高于对照组，高血压各组间比较收缩压和血压负荷值有较大差异。结论２４小时、日间、夜间的收缩压、舒张压及血压负荷值等参数诊断是高血压较重要的指标。     

老年卒中患者急性期血压变化及其与短期预后的关系

目的 探讨老年卒中患者急性期血压变化特征及其与30 d预后的关系.方法 采用前瞻性队列研究方法,连续登记2008年1月-2010年6月入院的老年卒中患者275例,其中脑梗死202例,脑出血73例.连续记录入院后7d的血压,在发病30d时评价预后.按照急性期7d内平均收缩压（120～139、140～159、160～179、180～199、＞200 mm Hg）和舒张压（＜69、70～79、80～89、90～99、＞100 mm Hg）水平分别分为5个亚组,比较入院时和30 d时的改良Rankin量表评分（mRS）、美国国立卫生研究院卒中量表评分（NIHSS）.结果 ①275例患者中,有66例预后差,其中脑出血组22例,脑梗死组44例,两组比较差异无统计学意义（P=0.200）.两组急性期7d内不同平均收缩压的30d预后差者的5个亚组预后比较,筹异有统计学意义（P＜0.05）.而急性期7 d内,不同平均舒张压水平的30 d预后差者,5个亚组比较,除70～79 mm Hg与80～89 mm Hg两组间差异无统计学意义外（P＞0.05）,其余各亚组之间预后比较差异有统计学意义（P＜0.05）.②平均收缩血压在160～179mmHg者,mRS（中位数2）和NIHSS（中位数7）评分较低,相应30d改善显著（mRS中位数差值为2,NIHSS中位数差值为4）;平均舒张压＞100 mm Hg,提示预后差,mRS和NIHSS评分30d改善的比较,不同舒张压亚组两两比较,差异有统计学意义（P＜0.05）.脑出血组平均舒张压在70～90mmHg范围内,往往预后较好;腩梗死组在70mm Hg以下者,预后最好.结论 老年卒中患者急性期7 d内平均收缩压在160～179mm Hg之间,30 d的预后较好;急性期平均舒张血压不能预测病情的严重程度,但可反映30 d预后转归的倾向.     

高血压病患者昼夜血压及性别与左室肥厚的关系

目的：研究高血压病（EH）患者昼夜血压变化和性别与左室肥厚（LVH）之间的关系，并探讨其临床意义。方法：对54例EH患者进行24h动态血压监测和超声心动图检查，男女性患者分成杓型和非杓型两组，比较昼夜血压变化与室间隔厚度、左室舒张末期内径、左室后壁厚度、左室重量等指标。结果：女性非杓型组LVH的程度及24h平均收缩压、夜间收缩压、睡眠时最低收缩压均较杓型组显著增加（P＜0．05和0．01）。而男性杓型与非杓型组之间各指标均无明显差异（均P＞0．05）。结论：女性EH患者LVH的程度非杓型者比杓型者更严重。