Ambulatory blood pressure variability is increased in diabetic hypertensives

The purpose of this study was to examine the possible difference in the 24-hr BP profile--including short-term BP variability, assessed as the standard deviation--between diabetic and non-diabetic hypertensives. We measured 24-hr ambulatory BP in 11 diabetic hypertensives (diabetic HT) and 10 non-diabetic hypertensives (non-diabetic HT) who were hospitalized for the educational program in our hospital and were under stable salt intake. Renal function and sleep apnea were also estimated. There were no significant differences in 24-hr systolic BP (141 mmHg vs. 135 mmHg, ns), daytime systolic BP (143 mmHg vs. 138 mmHg, ns), and nighttime systolic BP (135 mmHg vs. 130 mmHg, ns) between diabetic HT and non-diabetic HT. The values of 24-hr HR (69.7 beats/min vs. 65.2 beats/min, ns) and 24-hr HR variability (9.9 beats/min vs. 10.1 beats/min, ns) were also similar between the groups. Interestingly, diabetic HT had a significantly greater 24-hr systolic and diastolic BP variability than non-diabetic HT (18.2 mmHg vs. 14.5 mmHg, p < 0.05; 11.5 mmHg vs. 9.6 mmHg, p < 0.05, respectively). The values for creatinine clearance, urinary protein excretion, and apnea-hypopnea index were similar between the groups. Bivariate linear regression analysis demonstrated that fasting blood glucose was the primary determinant of 24-hr diastolic BP variability (r = 0.661, p < 0.01). Multiple stepwise regression analysis revealed that fasting blood glucose was a significant and independent contributor to 24-hr systolic BP variability (r = 0.501, p < 0.05). Taken together, these results demonstrate that BP variability is increased in diabetic hypertensives. Furthermore, it is possible that an elevation of fasting blood glucose may contribute to the enhanced BP variability in hypertensives.     

Ambulatory Blood Pressure and Heart Rate in Hypertensives with Renal Failure: Comparison between Diabetic Nephropathy and Non-Diabetic Glomerulopathy

The purpose of this study was to examine a possible difference in the 24-h blood pressure (BP) profile between hypertensives with diabetic nephropathy (DN) and those with non-diabetic glomerulopathy (non-DN). We measured 24-h ambulatory BP in 34 type 2 DN and 34 non-DN patients who were hospitalized for the educational program in our hospital. There were no significant differences in 24-h and daytime systolic BP between DN (143 vs. 136 mmHg, NS for 24-h systolic BP) and non-DN (143 vs. 138 mmHg, NS for daytime systolic BP). Although both groups disclosed blunted nocturnal decrease in BP and were classified as “non-dipper” type, DN patients had a significantly higher nighttime systolic BP than patients with non-DN (142 vs. 132 mmHg, p?=?0.0217). BP and heart rate (HR) variabilities were also estimated, and patients with DN showed a reduced nighttime HR variability than those with non-DN (4.8 vs. 6.6 beats/min, p?=?0.0115). DN patients had an increase in urinary protein excretion (3.0 vs. 1.4 g/day, p?=?0.0095) and a decrease in serum albumin concentration (3.1 vs. 3.7 mg/dl, p < 0.0001). Furthermore, urinary protein excretion was significantly correlated with nighttime systolic BP (r?=?0.480, p?=?0.0031) but not with nighttime HR variability. Taken together, these results demonstrate that the circadian rhythms of BP and HR are affected by underlying diseases and suggest that an elevated nighttime BP level may contribute to the enhanced urinary protein excretion in hypertensives with DN.     

Urinary angiotensinogen level is correlated with blood pressure level and proteinuria in patients with masked hypertension

Urinary <AQ: Please check whether all the edits made in this paper convey your intended meaning, and correct if necessary.>angiotensinogen (UAGT) level is an index of the intrarenal-renin angiotensin system status and is significantly correlated with blood pressure (BP) and proteinuria in patients with hypertension (HT). We aimed to investigate the possible relationship between UAGT levels and albuminuria in masked hypertensives. A total of 96 nondiabetic treated hypertensive patients were included in this study. The patients were divided into two groups: masked hypertensives (office BP <140/90 mmHg and ambulatory BP ≥130/80 mmHg) and controlled hypertensives (office BP <140/90 mmHg and ambulatory BP <130/80). The mean UAGT/UCre level and urinary albumin–creatinine ratio (UACR) of masked hypertensives were higher than those of controlled hypertensives (7.76 μg/g vs 4.02 μg/g, p < 0.001 and 174.21 mg/g vs 77.74 mg/g, p < 0.001, respectively). A significant positive correlation was found between UAGT/UCre levels and ambulatory systolic BP and diastolic BP levels in patients with masked HT, but this was not found with office SBP or DBP levels. Importantly, UAGT/UCre levels showed a significant positive correlation with UACR in both groups, but correlation of the UAGT levels with UACR was more pronounced in masked hypertensives (r = 0.854, p < 0.001 vsr = 0.512, p < 0.01). As a result, UAGT level was increased in patients with masked HT, which was associated with an elevation in albuminuria. Overproduction of the UAGT may play a pivotal role in development of proteinuria.     

Ambulatory blood pressure and heart rate in hypertensives with renal failure: comparison between diabetic nephropathy and non-diabetic glomerulopathy

The purpose of this study was to examine a possible difference in the 24-h blood pressure (BP) profile between hypertensives with diabetic nephropathy (DN) and those with non-diabetic glomerulopathy (non-DN). We measured 24-h ambulatory BP in 34 type 2 DN and 34 non-DN patients who were hospitalized for the educational program in our hospital. There were no significant differences in 24-h and daytime systolic BP between DN (143 vs. 136 mmHg, NS for 24-h systolic BP) and non-DN (143 vs. 138 mmHg, NS for daytime systolic BP). Although both groups disclosed blunted nocturnal decrease in BP and were classified as "non-dipper" type, DN patients had a significantly higher nighttime systolic BP than patients with non-DN (142 vs. 132 mmHg, p = 0.0217). BP and heart rate (HR) variabilities were also estimated, and patients with DN showed a reduced nighttime HR variability than those with non-DN (4.8 vs. 6.6 beats/min, p = 0.0115). DN patients had an increase in urinary protein excretion (3.0 vs. 1.4 g/day, p = 0.0095) and a decrease in serum albumin concentration (3.1 vs. 3.7 mg/dl, p < 0.0001). Furthermore, urinary protein excretion was significantly correlated with nighttime systolic BP (r = 0.480, p = 0.0031) but not with nighttime HR variability. Taken together, these results demonstrate that the circadian rhythms of BP and HR are affected by underlying diseases and suggest that an elevated nighttime BP level may contribute to the enhanced urinary protein excretion in hypertensives with DN.     

A Possible Relationship of Nocturnal Blood Pressure Variability with Coronary Artery Disease in Diabetic Nephropathy

Evidence suggests a relationship between short-term blood pressure (BP) variability and cardiovascular target-organ damage. Although a blunted nocturnal decrease in BP and reduced heart rate variability have been shown to be associated with cardiovascular morbidity in diabetic patients, little information is available on short-term BP variability. In this study, short-term BP variability was assessed in 36 subjects with type 2 diabetes and overt nephropathy who underwent ambulatory BP monitoring, and the factors that correlated with short-term BP variability were examined. The incidence of coronary artery disease (CAD) was significantly greater in the patients with increased 24-h systolic BP variability (67% versus 11%; p < 0.0005), while that of cerebrovascular disease was not significantly affected (61% versus 50%). Multiple stepwise regression analysis revealed that serum cholesterol (cholesterol) and plasma norepinephrine (p-NE) were significant and independent contributors to nighttime systolic BP variability (partial R² = 0.490, p < 0.001; partial R² = 0.470, p < 0.001) and demonstrated that body mass index and p-NE were primary determinants of nighttime diastolic BP variability (partial R² = 0.539, p < 0.0005; partial R² = 0.304, p < 0.05). Diabetic nephropathy patients with CAD had significantly increased daytime systolic (17.8 mmHg versus 13.1 mmHg, p < 0.0005), nighttime systolic (17.4 mmHg versus 10.5 mmHg, p < 0.0001), and nighttime diastolic (10.4 mmHg versus 7.2 mmHg, p < 0.05) BP variability. Furthermore, logistic regression analysis demonstrated that nighttime systolic BP variability was an independent risk factor for CAD (odds ratio 3.13 [95% CI 1.02–9.61]; p < 0.05). The increase in nighttime BP variability is associated with a proportional sympathetic activation in diabetic nephropathy. Elevated short-term BP variability combined with relative sympathetic prevalence during the night might represent an important risk factor for cardiovascular events in the diabetic population.     

Sequelae of Acute Hypoglycaemia on 24 hour Blood Pressure and Metabolic Parameters in Normal and Type 1 (Insulin-dependent) Diabetic Individuals

This study was performed to assess possible delayed after-effects of acute hypoglycaemia on blood pressure (BP) and heart rate (HR) over a 24-h period. Eleven insulin-dependent diabetic patients and 11 sex, age, and body mass index matched non-diabetic subjects were studied. Blood pressure was measured using a non-invasive ambulatory blood pressure monitor following acutely induced hypoglycaemia in the morning. No significant differences were observed in 24-h systolic and diastolic BP and HR in either groups, between the day when hypoglycaemia was induced and the day when plasma glucose was kept normal. In diabetic patients, hypoglycaemia induced a temporary but significant fall in mean BP (-7 ± 1 mmHg vs -2 ± 2; p < 0.05). Plasma glucose levels were significantly higher in insulin-dependent diabetic patients following hypoglycaemia than in those observed during the reference test. This study demonstrates that acute hypoglycaemia in insulin-dependent diabetic subjects does not cause significant alterations in 24-h BP in either diabetic or normal subjects.     

The Relationship Between Obesity,Plasma Immunoreactive Insulin Concentration and Blood Pressure in Newly Diagnosed Indian Type 2 Diabetic Patients

The association of blood pressure with clinical and biochemical measures was studied in 185 newly diagnosed Type 2 diabetic patients, 74 impaired-glucose-tolerant (IGT) and 128 non-diabetic control subjects. Hyperglycaemic subjects were older than control subjects (controls 40 (24–59) years, IGT 48 (29–64) years, diabetic 43 (29–60) years, median (5th-95th centile) both p < 0.05). They were also more obese (body mass index (BMI) controls 23.5 kg m^?2 (17.2–29.9), IGT 26.0 kg m^?2 (19.8–33.9), diabetic 24.2 kg m^?2 (19.3–32.2)) and with a greater waist-hip ratio (controls 0.83 (0.70–0.98), IGT 0.88 (0.75–0.98), diabetic 0.89 (0.75–1.00)). Blood pressure was significantly higher in both IGT (systolic 127mmHg (108–162), diastolic 80 mmHg (66–99)) and diabetic patients (systolic 130 mmHg (104–160), diastolic 84 mmHg (66–102)) compared to non-diabetic controls (systolic 120 mmHg (100–151), diastolic 80 mmHg (60–94)). Univariate analysis showed that in diabetic patients systolic blood pressure was related to age (r = 0.17, p < 0.05), BMI (r= 0.23, p < 0.01) and plasma immunoreactive insulin (fasting and post glucose, r= ? 0.25, p<0.01) but not to C-peptide concentrations; diastolic blood pressure to BMI (r= 0.35, p < 0.001), waist-hip ratio (r = 0.23, p < 0.01) and plasma immunoreactive insulin (fasting r= 0.30, p < 0.001, post glucose r = ? 0.20, p < 0.05) but not to C-peptide concentrations. Multivariate analysis revealed that systolic blood pressure in diabetic patients was related to BMI (p < 0.01) and fasting immunoreactive insulin (p < 0.05) while diastolic blood pressure was related to BMI (p < 0.001) and waist-hip ratio (p < 0.01). Thus, blood pressure is associated with obesity even in our relatively non-obese population and it is also associated with plasma immunoreactive insulin concentrations. The mechanism of these associations remains to be established.     

Ambulatory blood pressure variability is associated with restenosis after percutaneous coronary intervention in normotensive patients

Background

Previous studies have showed that BP variability is associated with cardiovascular events. However, no data were available regarding binary restenosis as an end-point after percutenous coronary intervention (PCI).

Methods and results

This multicenter study included 100 consecutive normotensive patients with stable coronary artery disease who were planned for PCI. Before the index procedure, office BP and 24-h ambulatory BP measurements were performed. BP variability indices including systolic and diastolic 24-h average, the day and the night values of standard deviation (SD) and variation coefficient (VC) were measured and calculated. All patients underwent repeat coronary angiography at 6-month. According to angiographic results, 2 groups were formed; a restenosis group (n = 30) with binary restenosis of the stented segment and a control group (n = 70) with a stenosis diameter of <50% in stented segment. Systolic SD and VC values for 24-h average (14.0 ± 2.8 mmHg vs. 9.5 ± 1.6 mmHg, p < 0.001 and 16% ± 3 vs. 11% ± 2, p < 0.001, respectively), the day (15.2 ± 3.9 mmHg vs. 10.6 ± 1.7 mmHg, p < 0.001 and 17% ± 4 vs. 12% ± 2, p < 0.001, respectively), and the night (12.8 ± 4.1 mmHg vs. 8.4 ± 2.4 mmHg, p < 0.001 and 14% ± 5 vs. 11% ± 3, p = 0.004, respectively) values were significantly higher in restenosis group compared to control group. Similarly, diastolic SD and VC values for 24-h average (10.6 ± 2.5 mmHg vs. 8.1 ± 1.5 mmHg, p < 0.001 and 12% ± 3 vs. 9% ± 2, p = 0.001, respectively), the day (11.1 ± 2.9 mmHg vs. 9.0 ± 1.8 mmHg, p = 0.003 and 12% ± 3 vs. 10% ± 2, p = 0.006, respectively), and the night (10.0 ± 3.6 mmHg vs. 7.2 ± 2.0 mmHg, p = 0.001 and 11% ± 5 vs. 9% ± 3, p = 0.059, respectively) values were significantly higher in restenosis group compared to no restenosis group except for diastolic VC night. All systolic and diastolic BP variability indices except diastolic VC night were found to be independent predictors of risk of restenosis in multivariate analysis. In addition, the cut-off values of 11.4 mmHg and 13% for 24-h systolic SD and VC, respectively, were found to be highly sensitive (93% for both) and specific (94% and 91%, respectively) for predicting binary restenosis at 6-month after PCI.

Conclusions

BP variability indices are significantly and independently associated with binary restenosis and higher values can predict restenosis after PCI sensitively and specifically.     

COMPARISON OF THE EFFECTS OF AMLODIPINE AND LOSARTAN ON 24-HOUR AMBULATORY BLOOD PRESSURE IN HYPERTENSIVE PATIENTS

Effects of amlodipine (AML), a long-acting calcium antagonist, and losartan (LOS), an angiotensin II receptor antagonist, on 24-hr blood pressure profile were compared in 15 patients with essential hypertension. After 4 weeks of placebo period, the patients were treated with AML or LOS in a random cross-over design for 12–16 weeks each. Either drug was given once daily at 0800 and the doses were titrated so that the office blood pressure was reduced lower than 140/90 mmHg. At the end of each period, 24-hr blood pressure was monitored. Average office blood pressure was lowered from 158 ± 2/ 98 ± 2 mmHg to 134 ± 1/87 ± 1 mmHg by AML and 134 ± 2/88 ± 1 mmHg by LOS. Average 24-hr blood pressure was also reduced from 144 ± 3/ 92 ± 2 mmHg to 131 ± 2/84 ± 2 mmHg by AML and 135 ± 3/85 ± 2 mmHg by LOS. The averaged 24-hr systolic blood pressure was significantly lower in AML than in LOS (p < 0.05). Then, the 24-hr blood pressure was analyzed for four segments; morning (0530–0900 h), daytime (0930–1800 h), evening (1830–2300 h) and night (2330–0500 h). Although the daytime blood pressure was comparable between AML and LOS, systolic blood pressure in the evening and morning hours were lower in AML than in LOS (133 ± 2 vs. 138 ± 3 mmHg, p < 0.01; 129 ± 3 vs. 134 ± 4, p < 0.05). Trough to peak ratio of antihypertensive effect on systolic blood pressure was significantly greater in AML than in LOS (62 ± 5% vs. 55 ± 4%, p < 0.05). Either drug did not cause reflective increase in pulse rate over 24 hours. These results suggest that both AML and LOS are equally effective in lowering daytime blood pressure without eliciting reflex tachycardia, however, the antihypertensive effect of AML lasts longer than that of LOS. Such information seems important to achieve 24-hr blood pressure control using these drugs.     

Evaluation of prehypertension and masked hypertension rate among clinically normotensive patients

Background: The present cross-sectional study was aimed to identify pre-hypertension and masked hypertension rate in clinically normotensive adults in relation to socio-demographic, clinical and laboratory parameters. Methods: A total of 161 clinically normotensive adults with office blood pressure (OBP) <140/90?mmHg without medication were included in this single-center cross-sectional study. OBP, home BP (HBP) recordings and ambulatory BP monitoring (ABPM) were used to identify rates of true normotensives, true pre-hypertensives and masked hypertensives. Data on sociodemographic and clinical characteristics were collected in each subject and evaluated with respect to true normotensive vs. pre-hypertensive patients with masked hypertension or true pre-hypertensive. Target organ damage (TOD) was evaluated in masked hypertensives based on laboratory investigation. Results: Masked hypertension was identified in 8.7% of clinically normotensives. Alcohol consumption was significantly more common in masked hypertension than in true pre-hypertension (28.6 vs. 0.0%, p?=?0.020) with risk ratio of 2.7 (95% CI 1.7–4.4). Patients with true pre-hypertension and masked hypertension had significantly higher values for body mass index, waist circumference, systolic and diastolic OBP and HBP (p?<?0.05 for each) compared to true normotensive subjects. ABPM revealed significantly higher values for day-time and night-time systolic and diastolic BP (p?=?0.002 for night-time diastolic BP, p?<?0.001 for others) in masked hypertension than true pre-hypertension. Conclusions: Given that the associations of pre-hypertension with TOD might be attributable to the high prevalence of insidious presentation of masked hypertension among pre-hypertensive individuals, ABPM seems helpful in early identification and management of masked hypertension in the pre-hypertensive population.     

Decline of Renal Function Is Associated with Proteinuria and Systolic Blood Pressure in the Morning in Diabetic Nephropathy

The aim of this study was to investigate a significance of increased proteinuria in the morning and the effects of antihypertensive treatment on proteinuria and arterial blood pressure in the progression of chronic renal insufficiency in type 2 diabetic patients with hypertension and nephropathy. In three 24-hr urine samples and blood pressure monitoring, separated into a night-and daytime and spot urine in the morning, variation in protein-creatinine ratio (g/g) and blood pressure were assessed in 24 (58 ± 3 years old; M/F: 17/7) diabetic patients with hypertension and nephropathy. Furthermore, the effects of antihypertensive therapy of combinations of angiotensin converting enzyme (ACE) inhibitor, calcium antagonists, diuretics, and α1 blocker were evaluated in 3 years. Home blood pressure measurement was carried out every month and 24-hr urine was collected every 2 months. The baseline urine excretion of protein-creatinine ratio and blood pressure were (1.22 ± 0.13 g/g creatinine: 154/96 ± 6/5 mmHg) in daytime and (1.39 ± 0.13: 168/88 ± 15/7) in the morning. At the end of the study, significant associations among a decline of 24-hr creatinine clearance and both of the urine excretion of protein-creatinine ratio (r = 0.47, p < .01) and the levels of systolic blood pressure (r = 0.46, p < .01) and between the levels of systolic blood pressure and the urine excretion of protein-creatinine ratio in the morning (r = 0.57, p < .001) were demonstrated. However, there were no significant associations among other variables. Analysis of patients who had systolic blood pressure in the morning less than 140 mmHg revealed that 65% of these patients received doxazosin-averaged doses of 4.8 ± 1.5 mg daily. The levels of both blood pressure and proteinuria-creatinine ratio in the morning mainly associate with progression of renal function in diabetic patients with hypertension and nephropathy.     

Ten‐year changes in ambulatory blood pressure: The prognostic value of ambulatory pulse pressure

Blood pressure (BP) changes and risk factors associated with pulse pressure (PP) increase in elderly people have rarely been studied using ambulatory blood pressure monitoring (ABPM). The aim is to evaluate 10‐year ambulatory blood pressure (ABP) changes in older hypertensives, focusing on PP and its associations with mortality. An observational study was conducted on 119 consecutive older treated hypertensives evaluated at baseline (T0) and after 10 years (T1). Treatment adherence was carefully assessed. The authors considered clinical parameters at T1 only in survivors (n = 87). Patients with controlled ABP both at T0 and T1 were considered as having sustained BP control. Change in 24‐hour PP between T0 and T1 (Δ24‐hour PP) was considered for the analyses. Mean age at T0: 69.4 ± 3.7 years. Females: 57.5%. Significant decrease in 24‐hour, daytime, and nighttime diastolic BP (all P < .05) coupled with an increase in 24‐hour, daytime, and nighttime PP (all P < .05) were observed at T1. Sustained daytime BP control was associated with lower 24‐hour PP increase than nonsustained daytime BP control (+2.23 ± 9.36 vs +7.79 ± 8.64 mm Hg; P = .037). The association between sustained daytime BP control and Δ24‐hour PP remained significant even after adjusting for age, sex, and 24‐hour PP at T0 (β=0.39; P = .035). Both 24‐hour systolic BP and 24‐hour PP at T0 predicted mortality (adjusted HR 1.07, P = .001; adjusted HR 1.25, P < .001, respectively). After ROC comparison (P = .001), 24‐hour PP better predicted mortality than 24‐hour systolic BP. The data confirm how ABP control affects vascular aging leading to PP increase. Both ambulatory PP and systolic BP rather than diastolic BP predict mortality in older treated hypertensives.     

Time and frequency domain estimates of spontaneous baroreflex sensitivity provide early detection of autonomic dysfunction in diabetes mellitus

Summary Diabetic autonomic dysfunction is associated with a high risk of mortality which makes its early identification clinically important. The aim of our study was to compare the detection of autonomic dysfunction provided by classical laboratory autonomic function tests with that obtained through computer assessment of the spontaneous sensitivity of the baroreceptor-heart rate reflex (BRS) by time domain and frequency domain techniques. In 20 normotensive diabetic patients (mean age ± SD 41.9 ± 8.1 years) with no evidence of autonomic dysfunction on laboratory autonomic testing (D0) blood pressure (BP) and ECG were continuously monitored over 15 min in the supine position. BRS was assessed as the slope of the regression line between spontaneous increases or reductions in systolic BP and linearly related lengthening or shortening in RR interval over sequences of at least 4 consecutive beats (sequence method), or as the squared ratio between RR interval and systolic BP spectral powers around 0.1 Hz. We compared the results with those of 32 age-matched normotensive diabetic patients with abnormal autonomic function tests (D1) and with those of 24 healthy age-matched control subjects with normal autonomic function tests (C). Compared to C, BRS was markedly less in D1 when assessed by both the slope of the two types of sequences (data pooled) and by the spectral method (–71.3 % and –60.2 % respectively, both p < 0.01). However, BRS was consistently although somewhat less markedly reduced in D0, the reduction being clearly evident for all the estimates (–57.0 % and –43.5 %, both p < 0.01). The effects were more evident than those obtained by the simple quantification of the RR interval variability. These data suggest that time and frequency domain estimates of spontaneous BRS allow earlier detection of diabetic autonomic dysfunction than classical laboratory autonomic tests. The estimates can be obtained by short non-invasive recording of the BP and RR interval signals in the supine patient, i. e. under conditions suitable for routine outpatient evaluation. [Diabetologia (1997) 40: 1470–1475] Received: 30 April 1997 and in revised form: 31 July 1997     

Analysis of Factors that Affect Short-Term Blood Pressure Variability in Patients with Chronic Renal Failure

Recent reports suggest the relationship of short-term blood pressure (BP) variability to cardiovascular target organ damage. In this study, short-term BP variability was assessed as the standard deviation of daytime and nighttime BP in 36 hospitalized patients with chronic renal failure (CRF) who underwent ambulatory BP monitoring. Positive correlations were observed between body mass index (BMI) and daytime systolic and diastolic BP variability, BMI and nighttime diastolic BP variability, cholesterol and daytime systolic BP variability, cholesterol and nighttime systolic and diastolic BP variability, nocturnal decline in BP and nighttime diastolic BP variability, and plasma concentration of norepinephrine (p-NE) and nighttime systolic BP variability. In multivariate linear regression analyses, BMI showed the strongest association with daytime and nighttime diastolic BP variability (p < .005 and p < .05). On the other hand, cholesterol and p-NE were the primary determinants of daytime and nighttime systolic BP variability, respectively (p < .01 and p < .0005). Interestingly, CRF patients with ischemic heart disease (IHD) had significantly increased daytime systolic and diastolic BP variability and nighttime systolic BP variability (p < .05 or less). Furthermore, logistic regression analysis demonstrated that nighttime systolic BP variability was an independent risk factor of IHD in patients with CRF (odds ratio 1.50 [95% confidence interval 1.01 to 2.25]; p < .05). Taken together, short-term BP variability is suggested to be affected by BMI, cholesterol, and p-NE in CRF patients. Furthermore, sympathetic nerve overactivitymay be involved in cardiovascular complications in CRF patients through the increase in nighttime systolic BP variability.     

The effects of sympathetic nervous system activation and psychological stress on glucose metabolism and blood pressure in subjects with Type 2 (non-insulin-dependent) diabetes mellitus

Summary The sympathetic nervous system may contribute to excessive hepatic glucose output in Type 2 (non-insulin dependent) diabetes mellitus and could be implicated in the interrelated problem of hypertension. The aim of these studies was to determine whether subjects with Type 2 diabetes had normal sensitivity (compared with age- and weight-matched non-diabetic subjects) to noradrenaline infusion (60 ng · kg^–1 · min^–1 for 60 min) and to compare the responses with oral tyramine administration (800 mg), and psychological stress (using competitive computer games). Noradrenaline infusion caused significantly greater plasma glucose (mean increment 2.1±0.4 vs 0.6±0.1 mmol/l, p<0.005) and pressor responses (mean systolic increment 21±3 vs 11±1mm Hg, p<0.02) in the diabetic subjects. The excessive glycaemia was due to increased hepatic glucose output rather than reduced glucose disposal. Tyramine administration caused significantly increased hepatic glucose output and plasma glucose levels, but with similar responses in the diabetic and non-diabetic subjects; the pulse and pressor responses were also similar between the groups. The psychological stressor induced significant increases in pulse, blood pressure and non-esterified fatty acid levels in the combined group of subjects (p<0.01) but did not influence plasma glucose levels in either diabetic or non-diabetic subjects. We conclude that pharmacologically-induced sympathetic nervous stimulation can induce hyperglycaemia. Subjects with uncomplicated Type 2 diabetes have increased sensitivity to exogenous noradrenaline but may not hyperrespond to endogenous sympathetic activation.     

Decreased left atrial myocardial strain in patients with suboptimal blood pressure control

Background: Suboptimal blood pressure (BP) control is commonly observed in patients receiving antihypertensive agents, but the relationship between uncontrolled BP and left atrial (LA) impairment remains unknown. Methods: This study enrolled 279 hypertensive patients who had been medicated, as well as 85 matched normal controls. The BP of systolic <140 mmHg and diastolic<90 mmHg was defined as optimal (HT1 group, n=146), otherwise as suboptimal BP control (HT2 group, n = 133). LA myocardial function was assessed by the systolic (S_Sa), early diastolic (S_Ea), and late diastolic (S_Aa) LA strains. Results: Both the HT1 group and HT2 group had higher BP reading, thicker interventricular septum, larger LA volume index, and enhanced active atrial emptying fraction than the control group (all <0.05). When compared with normal subjects, hypertensive patients displayed obvious reduction in the S_Sa (50.0 ± 10.9 vs. 35.9 ± 8.0%), S_Ea (30.1 ± 7.7 vs. 18.5 ± 7.1%) and S_Aa (19.9 ± 6.4 vs. 17.8 ± 4.2%) (all p < 0.001). In addition to a further impaired S_Ea found in the HT2 group than in the HT1 group (17.2 ± 5.3 vs. 19.8 ± 8.3%, p = 0.002), the treated BP of >140/90 mmHg appeared an independent risk factor associated with the abnormal S_Ea (odds ratio, 2.957; interval of confidence, 1.614-5.415; p = 0.001). Conclusions: Suboptimal BP control status in hypertensive patients is related to a further reduction of LA myocardial function assessed by the novel 2DSTI free strain, and suboptimal BP might be regarded as a composite risk factor and therefore a simplified treatment target. However, the prognostic value of LA free strain in patients with inability to achieve the BP target needs to be evaluated in future prospective studies.     

INSULIN RESISTANCE IS ASSOCIATED WITH REDUCED NOCTURNAL FALLS OF BLOOD PRESSURE IN NORMOTENSIVE,NONOBESE TYPE 2 DIABETIC SUBJECTS

To assess the relationship between insulin resistance and ambulatory blood pressure (BP) pattern, we determined glucose infusion rate (GIR) as a marker of insulin resistance using a glucose clamp method, and measured 24-h BPs in 25 normotensive, nonobese type 2 diabetic subjects. They were divided into two groups: 11 dippers and 14 nondippers. Clinical characteristics were similar in the two groups except for orthostatic fall in systolic BP. The median GIR level was significantly lower in nondippers than in dippers (P < 0.05). Spearman's rank correlation revealed that the GIRs were negatively correlated with the systolic, diastolic and mean BPs during nighttime (P < 0.05 or less), but not with daytime or whole day BPs. Moreover, based on a logistic regression analysis, the GIR as well as orthostatic fall in systolic BP discriminated independently between dippers and nondippers. Thus, our results suggest that insulin resistance is associated with decreased nocturnal BP fall in type 2 diabetic subjects.     

Exaggerated morning blood pressure surge and cardiovascular events. A 5-year longitudinal study in normotensive and well-controlled hypertensive elderly

Cardiovascular events (CE) occur most frequently in the morning hours in hypertensive subjects. We studied the association between the morning blood pressure (BP) surge and CE in prognosis of 10 normotensive and 32 well-controlled hypertensive elderly, in whom ambulatory BP monitoring was performed and who were followed prospectively for 5 years. The morning surge (MS) of BP was calculated as mean systolic BP during 2 h after awakening − mean systolic BP during 1 h that included the lowest sleep BP. During an average of 60 months, five CE occurred. When the patients were divided into two groups according to MS, those in the top terzile (MS group; MS ≥ 34 mmHg, n = 14) had a higher prevalence of CE (5 versus 0, p = 0.001) during the follow-up period, than the others (non-MS group; MS < 34 mmHg, n = 28). The logistic regression analysis showed the MS sleep-trough surge as predictive variable of CE (odds ratio, OR = 0.794, p = 0.022). In conclusion, in older normotensives and well-controlled hypertensives, a higher BP MS is associated with vascular risk independently of clinical and ambulatory BP. Reduction of the MS could thus be a therapeutic target for preventing vascular events also in non-hypertensive patients.     

Self‐measured worksite blood pressure and its association with organ damage in working adults: Japan Morning Surge Home Blood Pressure (J‐HOP) worksite study

The effects of elevations in blood pressure (BP) on worksite stress as an out‐of‐office BP setting have been evaluated using ambulatory BP monitoring but not by self‐measurement. Herein, we determined the profile of self‐measured worksite BP in working adults and its association with organ damage in comparison with office BP and home BP measured by the same home BP monitoring device. A total of 103 prefectural government employees (age 45.3 ± 9.0 years, 77.7% male) self‐measured their worksite BP at four timepoints (before starting work, before and after a lunch break, and before leaving the workplace) and home BP in the morning, evening, and nighttime (at 2, 3, and 4 a.m.) each day for 14 consecutive days. In the total group, the average worksite systolic BP (SBP) was significantly higher than the morning home SBP (129.1 ± 14.3 vs. 124.4 ± 16.4 mmHg, p = .026). No significant difference was observed among the four worksite SBP values. Although the average worksite BP was higher than the morning home BP in the study participants with office BP < 140/90 mmHg (SBP: 121.4 ± 9.4 vs. 115.1 ± 10.4 mmHg, p < .001, DBP: 76.0 ± 7.7 vs. 72.4 ± 8.4 mmHg, p = .013), this association was not observed in those with office BP ≥ 140/90 mmHg or those using antihypertensive medication. Worksite SBP was significantly correlated with the left ventricular mass index evaluated by echocardiography (r = 0.516, p < .0001). The self‐measurement of worksite BP would be useful to unveil the risk of hypertension in working adults who show normal office and home BP.     

Ambulatory pulse pressure, decreased nocturnal blood pressure reduction and progression of nephropathy in type 2 diabetic patients

Aims/hypothesis  We followed type 2 diabetic patients over a long period to evaluate the predictive value of ambulatory pulse pressure (PP) and decreased nocturnal BP reduction (non-dipping) for nephropathy progression. Methods  Type 2 diabetic patients (n = 112) were followed for an average of 9.5 (range 0.5–14.5) years. At baseline, all patients underwent 24 h ambulatory BP measurement. Urinary albumin excretion rate was evaluated by three urinary albumin:creatinine ratio measurements at baseline and follow-up. Results  At baseline, patients who subsequently progressed to a more advanced nephropathy stage (n = 35) had reduced diastolic night/day BP variation and higher 24 h systolic BP and PP values; they also had more advanced nephropathy and were more likely to smoke than those with no progression of nephropathy (n = 77). In a Cox regression analysis, independent predictors of nephropathy progression were 24 h PP (p < 0.01), diastolic night:day BP ratio (p = 0.02) and smoking (p = 0.02). The adjusted hazards ratio (95% CI) for each mmHg increment in 24 h PP was 1.04 (1.01–1.07), whereas the adjusted hazards ratio (95% CI) for each 1% increase in diastolic night:day BP ratio was 1.06 (1.01–1.11). Only one of 33 patients (3.0%) with both a diastolic night:day BP ratio and a 24 h PP below the median progressed, whereas 17 of 32 patients (53.1%) with both a diastolic night:day BP ratio and a 24 h PP equal to or above the median progressed to a more advanced nephropathy stage (p < 0.001). Conclusions/interpretation  Ambulatory PP, impaired nocturnal BP decline and smoking are strong, independent predictors of nephropathy progression in type 2 diabetic patients.