老年人直立性低血压

老年门诊病人直立性低血压的发生率为20％,75岁以上者高达30％。老年人的用药和疾病是发生直立性低血压的决定因素之一。本文着重讨论直立性低血压的病理生理、诊断和治疗。     

下肢和腹部加压弹力绷带可防治老年人直立性低血压病情恶化

如众所知,在老年人站立时可导致直立性低血压病情恶化。本文旨在就下肢和腹部加压弹力绷带在防治老年人直立性低血压及其相关症状中的作用进行了评价。对象与方法受试对象为21例患直立性低血压老人,平均年龄70±11岁。均在2次倾斜试验中被诱发出直立性低血压相关症状恶化。研究     

老年高血压病患者的直立性低血压患病率和肾上腺素能血管反应性[俄]／АбpaMOВИЧ СГ…／／КЛИН МeД

直立性低血压是老年人晕厥的主要原因之一。但对老年高血压病患者的直立性低血压还研究得不够。本文报告作者对老年高血压病患者的直立性低血压患病率和。肾上腺素能血管反应性进行研究的结果。     

老年直立不耐受患者的病因及直立倾斜试验特点分析

目的探讨老年人直立不耐受的主要病因构成和直立倾斜试验的特点。方法筛选我科门诊就诊的60岁以上初步诊断直立不耐受患者133例,排除器质性心脏病及其他疾病后,行直立倾斜试验明确诊断的患者114例,其中男性67例,女性47例,统计分析直立不耐受病因及倾斜试验的特点。结果直立不耐受患者直立倾斜试验阳性率53.5%,老年男性患者阳性率明显大于女性,差异有统计学意义(65.7%vs 36.2%,P<0.05)。在直立倾斜试验阳性患者中,主要病因为直立性低血压(67.2%),其次为血管迷走性晕厥(16.4%)和直立性高血压(16.4%)。诊断血管迷走性晕厥中,80.0%既往有至少1次晕厥发作,其中的87.5%在硝酸甘油诱发试验后出现阳性结果。诊断直立性低血压的患者中,根据低血压发生的时间,迟发性低血压(3～30min)占41.5%,其次是经典型直立性低血压(30s～3min内)占36.6%,而21.9%的患者提示为早期低血压(30s内一过性)。结论直立倾斜试验是鉴别老年直立不耐受性疾病的重要辅助检查。老年人直立不耐受的主要病因包括直立性低血压、血管迷走性晕厥和直立性高血压等。     

肾功能水平对老年直立性低血压患者脑缺血症状发生的影响

目的探讨肾功能水平对老年直立性低血压(OHP)患者脑缺血症状发生的影响。方法采用回顾性研究方法 ,收集我院75例直立性低血压患者脑缺血症状、卧立位血压、Ccr等临床资料,相关资料进行统计学分析。结果 Ccr与OHP有显著相关性;随着Ccr下降,有症状直立性低血压发病风险有增加趋势,Ccr对OHP的最佳预测节点为50.52 ml/min;进一步分析表明Ccr与卧立位收缩压差值(r=0.977,P=0.000)及卧立位舒张压差值(r=0.264,P=0.022)呈正相关。结论 Ccr与老年直立性低血压患者脑缺血相关症状的发生显著相关,其机制可能与卧立位收缩压差值相关。     

直立性低血压27例临床分析

直立性低血压是导致心肌梗死,脑卒中的危险因素.本文对27例直立性低血压进行临床分析,现报告于下.     

直立性低血压老人摄入葡萄糖的自律反应

老人有直立性低血压现象者约占11～33％。有些与用药有关,部分病人是由于自身调节功能减退或丧失。然而不少老人既未用药,自身调节功能又无问题,也可发生直立性低血压。自身调节欠佳引起的直立性低血压多出现在饭后。老人进食后如果     

直立性低血压的研究进展

本文论述了国外对直立性低血压在病因，发病机制及治疗方面的研究近况，强调了神经源性或非神经源性病因的确定对直立性低血压诊断及治疗的重要意义，也强调了个体化疗的重要性，指出，目前的治疗仅能减轻直立性低血压的症状，但未能逆转及稳定这种自主神经障碍的疾病进程。     

直立性低血压

直立性低血压(OH)又称体位性低血压,虽少见,但可导致严重后果。自1925年Bradhury等首先描述特发性直立性低血压(FOH)以来,对其病因、病理、诊断及治疗已有较多了解。一、正常直立体位时的血液动力改变及生理调节直立位时,约有300～800毫升的血液迅速郁积于下肢,致使静脉回流减少,心排出     

维生素B_(12)缺乏引起直立性低血压

直立性低血压是引起老年人发病和死亡的重要原因。其机理包括与年龄有关的生理变化、脱水、药物因素、中枢和周围神经系统的失调,但很少有人将维生素B_(12)缺乏与直立性低血压一起描述。本文介绍一例以直立性低血压作为唯一神经系统表现的维生素B_(12)缺乏症。     

Orthostatic hypotension-related hospitalizations in the United States

Background

Orthostatic hypotension has been commonly described in elderly persons and is associated with an increased risk of falls, syncope, and cerebrovascular events. Nevertheless, the precise burden of this condition in the US is currently unknown.

Methods

We analyzed discharge data from the Nationwide Inpatient Sample to identify orthostatic hypotension-related hospitalizations and associated comorbidities after excluding acute causes of this condition. National hospitalization rates were estimated using US census population estimates, and the medical conditions most frequently associated with orthostatic hypotension were assessed.

Results

In 2004, there were an estimated 80,095 orthostatic hypotension-related hospitalizations, yielding an overall rate of 36 (95% confidence interval, 34 to 38) hospitalizations per 100,000 US adults. Orthostatic hypotension was the primary diagnosis in 35% of these hospitalizations. The number of orthostatic hypotension-related hospitalizations increased steadily with age, and patients aged 75 years or older had the highest annual hospitalization rate, 233 per 100,000 (95% confidence interval, 217 to 249). The median length of hospital stay was 3 days (IQR 2-6) and the overall in-hospital mortality was 0.9%. Caucasian males were most likely to be hospitalized with orthostatic hypotension. Syncope was the most common comorbid condition reported among orthostatic hypotension patients.

Conclusions

Orthostatic hypotension is a relatively common condition among hospitalized US elderly patients. In light of the progressive aging of the US population, the contribution of orthostatic hypotension to morbidity and mortality is likely to increase, and deserves further scrutiny.     

24-hour blood pressure monitoring in the evaluation of supine hypertension and orthostatic hypotension

The presence of orthostatic hypotension has been shown to be a significant, independent predictor of all-cause mortality. Systolic and diastolic orthostatic hypotension, reversal of the circadian pattern, and postprandial hypotension are some of the hemodynamic factors that may contribute to the increased mortality seen in patients with orthostatic hypotension. The high variability of blood pressure in orthostatic hypotension cannot usually be adequately assessed by a one-time measurement. In this group of patients, 24-hour ambulatory.     

Relationship between glycemic control and orthostatic hypotension in type 2 diabetes mellitus--a survey by the Fukuoka Diabetes Clinic Group

We examined the prevalence of orthostatic hypotension and its association with glycemic control, as assessed by hemoglobin A1 (HbA1) concentration, in type 2 diabetic patients. The prevalence of orthostatic hypotension in 886 diabetics who were referred to our study and in 587 diabetics who were not given any antihypertensive drugs was 7% and 6%, respectively. The relationship between orthostatic hypotension and HbA1 levels was evaluated only in subjects not receiving antihypertensive drugs, since antihypertensive agents might induce orthostatic hypotension. HbA1 levels were 11.0 +/- 2.1% in the diabetic patients with orthostatic hypotension, which was significantly higher than the HbA1 levels of 9.9 +/- 2.2% in the diabetic patients without orthostatic hypotension. Multivariate analysis also revealed that the association remained significant after adjustment for the treatment and duration of diabetes, age, sex and body mass index. These findings suggest that glycemic control contributes to the development of orthostatic hypotension in type 2 diabetic patients.     

Autonomic responses to glucose ingestion in elderly subjects with orthostatic hypotension

The cardiovascular and plasma catecholamine responses to oral glucose (50 g) ingestion were investigated in five elderly subjects with orthostatic hypotension and five elderly control subjects. All the orthostatic hypotension subjects showed blood pressure falls after glucose ingestion, as compared to only one of the control subjects. Significantly greater falls in the orthostatic hypotension as compared to control patients were observed for systolic blood pressure (P less than 0.01) at 60 and 90 min following glucose and mean blood pressure (P less than 0.05) at 60 min following glucose. The orthostatic hypotension subjects did not have evidence of reduced heart-rate or plasma catecholamine responses to the glucose ingestion. It is concluded that, in elderly patients with orthostatic hypotension, disorder of blood pressure control may also cause hypotension associated with eating.     

Neurocirculatory abnormalities in Parkinson disease with orthostatic hypotension: independence from levodopa treatment

Patients with Parkinson disease often have orthostatic hypotension. Neurocirculatory abnormalities underlying orthostatic hypotension might reflect levodopa treatment. Sixty-six Parkinson disease patients (36 with orthostatic hypotension, 15 off and 21 on levodopa; 30 without orthostatic hypotension) had tests of reflexive cardiovagal gain (decrease in interbeat interval per unit decrease in systolic pressure during the Valsalva maneuver; orthostatic increase in heart rate per unit decrease in pressure); reflexive sympathoneural function (decrease in pressure during the Valsalva maneuver; orthostatic increment in plasma norepinephrine); and cardiac and extracardiac noradrenergic innervation (septal myocardial 6-[18F]fluorodopamine-derived radioactivity; supine plasma norepinephrine). Severity of orthostatic hypotension did not differ between the levodopa-untreated and levodopa-treated groups with Parkinson disease and orthostatic hypotension (-52+/-6 [SEM] versus -49+/-5 mm Hg systolic). The 2 groups had similarly low reflexive cardiovagal gain (0.84+/-0.23 versus 1.33+/-0.35 ms/mm Hg during Valsalva; 0.43+/-0.09 versus 0.27+/-0.06 bpm/mm Hg during orthostasis); and had similarly attenuated reflexive sympathoneural responses (97+/-29 versus 71+/-23 pg/mL during orthostasis; -82+/-10 versus -73+/-8 mm Hg during Valsalva). In patients off levodopa, plasma norepinephrine was lower in those with (193+/-19 pg/mL) than without (348+/-46 pg/mL) orthostatic hypotension. Low values for reflexive cardiovagal gain, sympathoneural responses, and noradrenergic innervation were strongly related to orthostatic hypotension. Parkinson disease with orthostatic hypotension features reflexive cardiovagal and sympathoneural failure and cardiac and partial extracardiac sympathetic denervation, independent of levodopa treatment.     

Measuring orthostatic hypotension with the Finometer device: is a blood pressure drop of one heartbeat clinically relevant?

OBJECTIVE: The role of orthostatic hypotension in falls in older people is generally accepted. Because of the high degree of intra- and interobserver variability in conventional measurements of orthostatic hypotension, application of continuous measurement systems has been proposed. The clinical relevance of a blood pressure drop lasting one heartbeat, however, is unknown. We therefore investigated which time average of continuous-finger-blood-pressure measurement (Finometer) showed the best association between orthostatic hypotension and falls. This was also compared with conventional sphygmomanometer measurements. METHODS: In 217 geriatric outpatients supine and standing (finger) blood pressure to diagnose orthostatic hypotension was monitored with Finometry (beat-to-beat and 1, 5, 10, 15, 20 and 30 s averages) and sphygmomanometry. History of fall incidents (previous year) was registered. RESULTS: The best association (C=0.22, P=0.003) with falls history was found for the 5-s average of Finometry, whereas falls and orthostatic hypotension assessed by sphygmomanometry did not correlate. The odds ratio of a fall according to orthostatic hypotension using the 5-s average was 2.54 (95% CI: 1.37 to 4.71). CONCLUSIONS: Orthostatic hypotension and falls are correlated when using Finometry, with the best association found when using 5-s averages. As the etiology of falls is often multifactorial, orthostatic hypotension and falls are poorly correlated, irrespective of the method or time average that is applied.     

Orthostatic blood pressure changes and diabetes duration

To determine the prevalence and the associated clinical characteristics of orthostatic hypotension and orthostatic hypertension in patients with diabetic sensorimotor polyneuropathy (DSP).MethodsA single-center retrospective cross-sectional study was conducted on 200 DSP patients who had 3-minute orthostatic measures as part of the standard clinic evaluation. We measured the heart rate (HR) and blood pressure (BP) supine and again after 3 min of standing.ResultsThe prevalence of orthostatic hypotension was 19.5% and that of orthostatic hypertension was 23%. Subjects with orthostatic hypotension had significantly longer diabetes duration than subjects who were normotensive and those with orthostatic hypertension. Quantitatively, BP changes from supine to standing correlated with diabetes duration (R = 0.306; P = 0.0582) and age (R = 0.434; P = 0.006) in subjects with orthostatic hypotension.ConclusionsOrthostatic hypertension and orthostatic hypotension are frequent in patients with DSP. Orthostatic hypertension is associated with shorter diabetes duration than orthostatic hypotension.     

Hypovolemia contributes to the pathogenesis of orthostatic hypotension in patients with diabetes mellitus.

PURPOSE: To investigate whether body sodium content and blood volume contribute to the pathogenesis of orthostatic hypotension in patients with diabetes mellitus. SUBJECTS AND METHODS: Exchangeable sodium, plasma and blood volumes, and catecholamine, renin, and aldosterone levels were assessed in 10 patients with Type II diabetes mellitus who had orthostatic hypotension and control groups of 40 diabetic patients without orthostatic hypotension and 40 normal subjects of similar age and sex. In subgroups, clinical tests of autonomic function and cardiovascular reactivity to norepinephrine and angiotensin II infusions were performed. RESULTS: In diabetic patients with orthostatic hypotension, mean (+/- SD) supine blood pressure was 165/98 +/- 27/12 mm Hg (P <0.05 compared with other groups) and mean upright blood pressure was 90/60 +/- 38/18 mm Hg. Compared with controls, diabetic patients with orthostatic hypotension had a 10% lower blood volume. They also had less exchangeable sodium than patients with diabetes who did not have orthostatic hypotension (P <0.01). Compared with both groups of controls, diabetic patients with orthostatic hypotension had decreased 24-hour urinary norepinephrine excretion and a reduced diastolic blood pressure response to handgrip (P <0.05). Moreover, they displayed reduced products of exchangeable sodium or blood volume and sympathetic function indexes. Cardiovascular pressor reactivity to norepinephrine was enhanced (P <0.01) and beat-to-beat variation decreased (P <0.01) in both groups of diabetic patients. Microvascular complications were more prevalent in the diabetic patients with orthostatic hypotension (90% vs 35%). CONCLUSIONS: Patients who have Type II diabetes mellitus and orthostatic hypotension are hypovolemic and have sympathoadrenal insufficiency; both factors contribute to the pathogenesis of orthostatic hypotension.     

2型糖尿病患者体位性低血压的临床因素分析

目的 研究2型糖尿病患者体位性低血压的临床因素.方法 分析168例2型糖尿病患者静息状态下以及站立后1~10 min内的每分钟血压.结果 体位性低血压组与非体位性低血压组两组比较,前者年龄较大、卧位收缩压较高、糖化血红蛋白水平较高、合并高血压的比率较高;Logistic回归分析提示体位性低血压的发生与年龄、卧位收缩压、糖化血红蛋白水平、合并高血压病独立正相关.结论 合并高血压病的2型糖尿病患者应加强血压、血糖的管理,减少体位性低血压的发生.     

Syncope and orthostatic hypotension

PURPOSE: The purpose of this study was to determine the postural blood pressure response over time, the prevalence of orthostatic hypotension in patients with syncope, and the relationship of orthostatic hypotension to recurrence of symptoms. PATIENTS AND METHODS: We prospectively evaluated 223 patients with syncope in a standardized manner. Orthostatic responses were measured in a standardized fashion at 0, 1, 2, 3, 5, and 10 minutes or until symptoms occurred. Follow-up was obtained at 3-month intervals. Causes of syncope were assigned by predetermined criteria. RESULTS: Orthostatic hypotension (20 mm Hg or greater systolic blood pressure decline) was found in 69 patients (31%). The median time to reach minimal standing systolic blood pressure was 1 minute for all subjects. In patients with orthostatic hypotension (20 mm Hg or greater), mean time to reach minimum blood pressure was 2.4 minutes. The vast majority of patients with significant orthostatic hypotension had this finding within 2 minutes of standing. Orthostatic hypotension was common in patients for whom other probable causes of syncope were assigned. The recurrence of syncope was not related to the degree of orthostatic hypotension; however, the recurrence of dizziness and syncope as end-points was lower in patients with 20 mm Hg or greater systolic blood pressure reductions as compared with patients with lesser degrees of orthostatic blood pressure declines. CONCLUSION: Orthostatic hypotension is common in patients with syncope and is detected in the vast majority of patients by 2 minutes. Although symptom recurrence on follow-up was lower in patients with more severe orthostatic hypotension, the clinical significance of this finding needs to be further defined by future studies.