Which Measurement of Blood Pressure Is More Associated With Albuminuria in Patients With Type 2 Diabetes: Central Blood Pressure or Peripheral Blood Pressure?

The aim of this study was to investigate whether central systolic blood pressure (SBP) was associated with albuminuria, defined as urinary albumin excretion (UAE) ≥30 mg/g creatinine, and, if so, whether the relationship of central SBP with albuminuria was stronger than that of peripheral SBP in patients with type 2 diabetes. The authors performed a cross‐sectional study in 294 outpatients with type 2 diabetes. The relationship between peripheral SBP or central SBP and UAE using regression analysis was evaluated, and the odds ratios of peripheral SBP or central SBP were calculated to identify albuminuria using logistic regression model. Moreover, the area under the receiver operating characteristic curve (AUC) of central SBP was compared with that of peripheral SBP to identify albuminuria. Multiple regression analysis demonstrated that peripheral SBP (β=0.255, P<.0001) or central SBP (r=0.227, P<.0001) was associated with UAE. Multiple logistic regression analysis demonstrated that peripheral SBP (odds ratio, 1.029; 95% confidence interval, 1.016–1.043) or central SBP (odds ratio, 1.022; 95% confidence interval, 1.011–1.034) was associated with an increased odds of albuminuria. In addition, AUC of peripheral SBP was significantly greater than that of central SBP to identify albuminuria (P=0.035). Peripheral SBP is superior to central SBP in identifying albuminuria, although both peripheral and central SBP are associated with UAE in patients with type 2 diabetes.     

Risers and Extreme‐Dippers of Nocturnal Blood Pressure in Hypertension: Antihypertensive Strategy for Nocturnal Blood Pressure

There is increasing evidence that disruption of diurnal blood pressure (BP) variation is a risk factor for hypertensive target organ damage and cardiovascular events. Especially, the risers (extreme non‐dippers), who exhibit a nocturnal BP increase compared with daytime BP, have the worst cardiovascular prognosis, both for stroke and cardiac events. On the other hand, extreme‐dippers (with marked nocturnal BP falls) are at risk for non‐fatal ischemic stroke and silent myocardial ischemia, particularly extreme‐dippers complicated with atherosclerotic arterial stenosis and excessive BP reduction due to antihypertensive medication. Extreme‐dipping status of nocturnal BP is closely associated with excessive morning BP surge and orthostatic hypertension. Hypertensive patients who have these conditions and exhibit marked BP variations are likely to have silent cerebral infarct and to be at high‐risk with regard to future stroke. Individualized antihypertensive medication targeting disrupted diurnal BP variation might thus be beneficial for such high‐risk hypertensive patients.     

Dietary Factors and Blood Pressure of Tibetan Population in Lhasa

随机抽取拉萨市４９～５４岁年龄组藏族居民１０８人，测定血压、体重指数，收集２４ｈ尿标本，测尿中钠、钾、钙、镁、尿素氮及氨基酸，采血测定总胆固醇、各型脂肪酸及电解质等指标，探讨拉萨藏族人群的饮食因素与血压水平的关系。研究设计及方法按ＣＡＲＤＩＡＣ研究方案实施，生化指标由ＣＡＲＤＩＡＣ中心统一分析。结果显示。收缩压、舒张压、高血压患病率、尿钠及钠／钾比等变量均升高；尿钙、镁、牛磺酸、１－甲基组氨酸等变量均降低。尿镁、３－甲基组氨酸、总胆固醇等分别与收缩压及舒张压呈显著负相关；血清豆蔻酸与收缩压及舒张压呈显著正相关。上述诸因子进入多元回归方程，提示拉萨藏族人群饮食中的多种营养素摄取失调与血压水平及高血压患病率均高可能有一定的关系。     

The Accuracy of Clinician Perceptions of “Usual” Blood Pressure Control

BACKGROUND The term “clinical inertia” is used to describe the failure to manage a chronic condition aggressively enough to bring it under control. The underlying mechanisms for clinical inertia remain poorly understood. OBJECTIVE To describe one potential mechanism for clinical inertia, seen through the lens of clinician responses to a computerized hypertension reminder. DESIGN Cohort study. PARTICIPANTS A total of 509 hypertensive patients from 2 primary care clinics in urban Veterans Health Administration (VA) Medical Centers. All patients had elevated blood pressure (BP) values that triggered a computerized reminder. Given a set of possible responses to the reminder, clinicians asserted at least once for each patient that medication adjustments were unnecessary because the BP was “usually well controlled”. MEASUREMENTS Using recent BP values from the electronic medical record, we assessed the accuracy of this assertion. RESULTS In most instances (57%), recent BP values were not well controlled, with the systolic BP (56%) much more likely to be elevated than the diastolic BP (13%). Eighteen percent of recent systolic BP values were 160 mmHg or greater. CONCLUSIONS When clinicians asserted that the BP was “usually well controlled”, objective evidence frequently suggested otherwise. This observation provides insight into one potential mechanism underlying clinical inertia.     

Are There Benefits of Antihypertensive Therapy Beyond Blood Pressure Lowering?

Meta-analyses strongly suggest that the primary preventive benefit of antihypertensive therapy in uncomplicated individuals is the direct result of the lower blood pressure (BP) rather than the choice of agents. In contrast, when comorbidities are present, therapeutic benefit is governed primarily by the appropriateness of the drug class for the comorbidity profile. As progressively lower BP levels are studied, conflicting results and uncertainties continue to emerge. Given the geometric nature of the BP-risk relationship, it is to be expected that benefits will be less dramatic at lower levels of BP. Conflicting results may emerge from intrinsic problems with clinical trials, including uncertainties related to confounded composite end points, interactions of comorbidities, selection bias from the heterogeneous population with hypertension, interindividual response differences, BP variation and measurement artifacts, multiple mechanisms of antihypertensive drugs, and other deficiencies in study design. The mandate for BP reduction remains strong in virtually all clinical situations. Because of clinical heterogeneity, however, no single drug class is preferred in all circumstances.     

Does Blood Pressure Variability Modulate Cardiovascular Risk?

Exactly how hypertension causes end organ damage and vascular events is poorly understood. Yet the concept that underlying “usual” blood pressure (BP) accounts for all BP-related risk of vascular events and for the benefits of BP-lowering drugs has come to underpin clinical guidelines on the diagnosis and treatment of hypertension. This article reviews evidence that variability in BP also predicts risk of stroke and other vascular events independently of mean BP and evidence that drug-class effects on variability in BP explain differences in the effectiveness of BP-lowering drugs in preventing stroke.     

Masked Hypertension Assessed by Ambulatory Blood Pressure Versus Home Blood Pressure Monitoring: Is It the Same Phenomenon?

BACKGROUND: Masked hypertension is defined as normal clinic blood pressure (CBP) and elevated out-of-clinic blood pressure assessed using either self-monitoring of blood pressure (BP) by the patients at home (HBP) or ambulatory BP (ABP) monitoring. This study investigated the level of agreement between ABP and HBP in the diagnosis of masked hypertension. METHODS: Participants referred to an outpatient hypertension clinic had measurements of CBP (two visits), HBP (4 days), and ABP (24 h). The diagnosis of masked hypertension based on HBP (CBP <140/90 mm Hg and HBP > or =135/85) versus ABP (CBP <140/90 and awake ABP > or =135/85) was compared. RESULTS: A total of 438 subjects were included (mean age +/- SD, 51.5 +/- 11.6 years; 59% men and 41% women, 34% treated and 66% untreated). Similar proportions of subjects with masked hypertension were diagnosed by ABP (14.2%) and HBP (11.9%). In both treated and untreated subjects, the masked hypertension phenomenon was as common as the white coat phenomenon. Among 132 subjects with normal CBP, there was disagreement in the diagnosis of masked hypertension between the HBP and the ABP method in 23% of subjects for systolic and 30% for diastolic BP (kappa 0.56). When a 5-mm Hg gray zone for uncertain diagnosis was applied to the diagnostic threshold, the disagreement was reduced to 9% and 6% respectively. CONCLUSIONS: Similar proportions of subjects with masked hypertension are detected by ABP and HBP monitoring. Although disagreement in the diagnosis between the two methods is not uncommon, in the majority of these cases the deviation of the diagnostic BP above the threshold in not clinically important. Both ABP and HBP monitoring appear to be appropriate methods for the detection of masked hypertension.     

Blood Pressure Measurement: Sitting and Standing?

Prior to discussing some thoughts about positional changes in blood pressure, I'd like to comment on the me- asurement of blood pressure.It is rare for a medical student, a resident-in-training, a cardiovascular fellow-in-training, or even a practicing or academic cardiologist to take the patient's blood pressure. I would even go so far as to say that it is uncommon for a registered nurse to measure blood pressure. Copyright (c) 2008 Wiley Periodicals, Inc.     

How Reliable Is Nighttime Blood Pressure Dipping?

This report examines the reliability of nighttime blood pressure dipping. Twenty-one individuals were studied twice with ambulatory blood pressure monitoring. On one occasion they were studied as outpatients, and on the other as inpatients on a clinical research ward. Blood pressure monitoring revealed the expected dip in blood pressure at nighttime. However, there was little test–retest reliability across the two settings. The test–retest correlations for the dip in blood pressure across the two settings were nonsignificant for systolic, diastolic, and mean arterial blood pressure. Caution is advised before diagnosing dipping or nondipping on the basis of one 24-h ambulatory blood pressure recording.     

Disorders of Blood Pressure Regulation—Role of Catecholamine Biosynthesis,Release, and Metabolism

Catecholamines (epinephrine and norepinephrine) are synthesised and produced by the adrenal medulla and postganglionic nerve fibres of the sympathetic nervous system. It is known that essential hypertension has a significant neurogenic component, with the rise in blood pressure mediated at least in part by overactivity of the sympathetic nervous system. Moreover, novel therapeutic strategies aimed at reducing sympathetic activity show promise in the treatment of hypertension. This article reviews recent advances within this rapidly changing field, particularly focusing on the role of genetic polymorphisms within key catecholamine biosynthetic enzymes, cofactors, and storage molecules. In addition, mechanisms linking the sympathetic nervous system and other adverse cardiovascular states (obesity, insulin resistance, dyslipidaemia) are discussed, along with speculation as to how recent scientific advances may lead to the emergence of novel antihypertensive treatments.     

Home Blood Pressure Monitoring: How Good a Predictor of Long-Term Risk?

Most management decisions for the diagnosis and treatment of hypertension are made using blood pressure (BP) measurements made in the clinic. However, home BP recordings may be of superior prognostic value. In this review, we show that home BP recordings are generally superior to clinic BP measurements in predicting long-term prognosis. Home BP has been shown to significantly predict important end points including all-cause mortality, progression of chronic kidney disease, and functional decline in the elderly. In addition, home BP recordings significantly and strongly predict cardiovascular events. These findings are robust, as they concur despite having been studied in disparate populations, using heterogeneous methods of clinic and home BP measurement, and with varied methods of statistical analysis. The advantages of home BP recordings are not due solely to a larger number of measurements, and they extend to the elderly, patients with chronic kidney disease, and those on hemodialysis. Because home BP recordings combine improved accuracy with the advantages of low cost and easy implementation, most patients with known or suspected hypertension should have their BP assessed and managed by means of home BP recordings.