Rosiglitazone reduces office and diastolic ambulatory blood pressure following 1-year treatment in non-diabetic subjects with insulin resistance

OBJECTIVE: Rosiglitazone (RSG) has been reported to reduce blood pressure (BP) in patients with type-2 diabetes, but similar effects in non-diabetic people with insulin resistance is less clear. Our aim was to test the long-term BP-lowering effects of RSG compared with placebo. METHODS: We recruited participants for BP evaluation of RSG treatment from a larger intervention trial. Office BP was recorded in 355 non-diabetic subjects with insulin resistance randomized to receive either RSG or placebo for 52 weeks. Ambulatory BP monitoring (ABPM; Spacelab 90207) was performed in a subgroup of 24 subjects (RSG: n = 11; placebo n = 13). RESULTS: After 1 year, the office BP decreased by -3.1 mmHg systolic (p<0.05) and -3.8 mmHg diastolic (p<0.001) in the RSG group versus placebo. In patients treated with RSG, at 1 year there was a trend for a reduction from baseline for mean 24-h diastolic BP (DBP), daytime DBP and night-time DBP (-4.39, -5.26 and -2.93 mmHg, respectively). However, only daytime DBP was significantly lower in the RSG group compared with control (adjusted mean difference: -4.41 mmHg, p = 0.007). There was also a non-significant trend for a reduction in mean 24-h systolic BP (SBP), daytime SBP and night-time SBP (-2.70, -2.51 and -3.35 mmHg, respectively). CONCLUSIONS: RSG treatment for 1 year was associated with a small but significant decrease in diastolic 24-h ambulatory diastolic BP, and both systolic and diastolic office BPs in non-diabetic people with insulin resistance.     

Early alterations of blood pressure in normotensive and normoalbuminuric Type 1 diabetic patients

With the objective to examine patterns of blood pressure (BP) in normotensive and normoalbuminuric Type 1 diabetic patients during 24 h ambulatory blood pressure monitoring (ABPM) we studied 28 Type 1 diabetic patients aged 27+/-7.1 years with a disease duration of 9+/-6.6 years, and 28 non-diabetic normotensive subjects aged 25+/-6.5 years matched to the diabetic group for age, gender, skin color, weight, height, body mass index, clinic BP and absence of microalbuminuria. Systolic BP (sBP) and diastolic BP (dBP) were recorded for 24 h, daytime and nighttime. SBP and dBP burden, night/day BP ratios and percent nighttime BP fall were determined. Subjects with a nocturnal fall in either sBP or dBP of less than 10% of daytime values were classified as non-dippers. Both sBP (111+/-7.1 vs. 104+/-9 mmHg; P=0.003) and dBP nighttime (66+/-6.1 vs. 61+/-5.3 mmHg; P=0.001) were higher in diabetic patients than non-diabetic subjects. Night/day ratios for sBP (0.93+/-0.04 vs. 0.89+/-0.05; P=0.006) and dBP (0.86+/-0.06 vs. 0.82+/-0.06; P=0.007) were higher in diabetics. The loss of a fall in sBP was more prevalent in diabetic subjects (78 vs. 39%; P=0.007). Non-dippers for sBP and dBP in the diabetic group had higher BP burden during the nighttime (21.4+/-16.6 vs. 3.2+/-3.9%; P=0.01 and 21.9+/-10 vs. 3.7+/-5.5%; P<0.001, respectively). Our data demonstrate higher sBP and dBP during the nighttime and loss of the nocturnal fall in BP in Type 1 diabetic patients. Further prospective studies are needed to define if high BP burden in diabetic non-dippers during the night could represent a risk for nephropathy and cardiovascular disease.     

White coat effect and white coat hypertension in community pharmacy practice

OBJECTIVE: The aim of the present study was to investigate whether a white coat effect (WCE) can be observed and quantified in community pharmacy practice. METHODS: In five community pharmacies of Basel, Switzerland, clients asking for blood pressure (BP) measurement were recruited to participate in a free of charge study. Blood pressure was measured in four different settings: pharmacy (using mercury sphygmomanometers), outpatient clinic (measurement by a nurse using mercury sphygmomanometers), self-measurement at home (using automated wrist devices) and daytime ambulatory BP (ABP) monitoring (using SpaceLabs 90207 monitors). WCE was defined as the difference between pharmacy or outpatient and daytime ABP. RESULTS: A total of 50 subjects completed all measurements (42% male, mean age 53.7 years+/-14.0). Blood pressure values of the different settings: (means in mmHg+/-SD, systolic; diastolic): pharmacy BP 129+/-19; 82+/-10, outpatient clinic BP 127+/-15; 82+/-10, home BP 119+/-15; 73+/-9, daytime ABP 124+/-10; 79+/-8. Pharmacy BP was significantly higher (P=0.03 systolic; P=0.02 diastolic) compared with daytime ABP and differences among subjects with antihypertensive medication (n=22) were even more significant (P<0.01). Individual differences were found between pharmacy BP and daytime ABP: +4.6+/-14.8; +2.9+/-8.3. Outpatient BP was significantly higher compared with daytime ABP in diastolic (P=0.04) but not in systolic values. Individual differences between outpatient BP and daytime ABP were +2.5+/-13.1; +2.8+/-9.2. 'Clinically important WCE' (>or=20 mmHg systolic or >or=10 mmHg diastolic) was observed in 24% of all subjects in the pharmacy and in 20% in the outpatient clinic. CONCLUSIONS: Our findings show that WCE and white coat hypertension exist in community pharmacy practice and are similar to the effects in an outpatient clinic.     

Out-of-office blood pressure in children and adolescents: disparate findings by using home or ambulatory monitoring

BACKGROUND: The validity of home blood pressure (HBP) measurements in children has not been evaluated, although in clinical practice such measurements are being used. This study compares HBP, with clinic (CBP) and daytime ambulatory blood pressure (ABP) in children and adolescents. METHODS: Fifty-five children and adolescents aged 6 to 18 years were evaluated with CBP (three visits), HBP (6 days), and daytime ABP. Mean age was 12.3 +/- 2.9 (SD) years, 33 boys. According to the Task Force CBP criteria, 26 were hypertensives, 6 had high-normal BP (hypertensive group), and 23 were normotensives (normotensive group). RESULTS: In the hypertensive group, CBP was 130.8 +/- 7.6/72.5 +/- 8.1 mm Hg (systolic/diastolic), HBP 118.9 +/- 6.3/73.7 +/- 6.7, and ABP 130.8 +/- 8.1/75.5 +/- 8.3. In the normotensive group, CBP was 112.8 +/- 8/63.1 +/- 6.3, HBP 106.7 +/- 8.4/67.2 +/- 5.2, and ABP 123.9 +/- 7.2/72 +/- 4.3. Strong correlations (P < .001) were observed between CBP-HBP (r = 0.73/0.57, systolic/diastolic), CBP-ABP (r = 0.59/0.49), and HBP-ABP (r = 0.72/0.66). In normotensive subjects, ABP was higher than both CBP and HBP for systolic and diastolic BP (P < .001). Furthermore, systolic HBP was lower than CBP (P < .01), whereas the opposite was true for diastolic BP (P < .05). In hypertensive subjects systolic HBP was lower than both CBP and ABP (P < .001), whereas CBP did not differ from ABP. For diastolic BP no differences were found among measurement methods. CONCLUSIONS: These data suggest that, in contrast to adults in whom HBP is close to the levels of daytime ABP, in children and adolescents HBP appears to be significantly lower than daytime ABP. Until more data become available, caution is needed in the interpretation of HBP in children and adolescents.     

Office blood pressure underestimates ambulatory blood pressure in peripheral arterial disease in comparison to healthy controls

Patients with peripheral arterial disease (PAD) constitute a subgroup of high-risk hypertensives, but controlled studies on 24-h blood pressure (BP) and diurnal variation of BP are lacking. This study was performed in order to test the hypothesis that office BP (OBP) may underestimate 24-h BP in PAD patients in comparison to a matched control group. In all, 98 male patients (mean age 68 years) with a history of intermittent claudication and an ankle/brachial index less than 0.9, and 94 controls matched for age but without PAD or ischaemic heart disease performed 24-h recordings of ambulatory BP. A total of 59 patients had a history of hypertension and 69 were on treatment with BP-lowering drugs as compared to 17 and 23 of the control subjects, respectively. Office as well as 24-h systolic BP (SBP) were higher in patients as compared to controls (151 +/- 22 vs 140 +/- 20 mmHg, P < 0.001 and 142 +/- 14 vs 133 +/- 15 mmHg, P < 0.001, respectively), but did not differ with regard to diastolic BP. In an analysis of covariance with the continuous factors age, office SBP and the categorical factor antihypertensive treatment, 24-h SBP was higher in PAD patients compared to controls (P < 0.05). The difference between office and night SBP was lower in PAD patients with antihypertensive treatment compared to controls (P = 0.01). In conclusion, Male patients with PAD had higher systolic but not diastolic BP than age-matched control subjects. In PAD patients, 24-h SBP was higher than expected from OBP compared to controls. Night SBP was higher only in patients with antihypertensive treatment. In PAD patients, especially when on antihypertensive treatment, the severity of hypertension may be underestimated when based on OBP only.     

Double-blind evaluation of slow-release nicardipine using different methods of blood pressure measurement. Predictive value of the acute response to intravenous nicardipine

Forty hypertensive patients (diastolic greater than 95 mmHg) were included after 15 days of a single blind placebo period in a randomized placebo controlled double-blind study to assess the antihypertensive effect of a new galenic form of nicardipine (N) administered 50 mg b.i.d. for 3 weeks. They comprised 27 men and 13 women aged from 27 to 72 years (mean: 53 +/- 10). Blood pressure (BP) was measured in hospital before morning drug intake by an automatic recorder (Sentron) in supine position for 30 minutes (min) and by a mercury sphygmomanometer. Ambulatory BP was assessed by a portable patient activated recorder (Remler 2000). Mercury sphygmomanometer supine BP under N fell from 160 +/- 21/104 +/- 6 mmHg to 151 +/- 14/98 +/- 8 mmHg (n = 20; p less than 0.01/p less than 0.01) whereas BP under placebo (P) was respectively 158 +/- 14/103 +/- 6 mmHg and 156 +/- 20/102 +/- 9 mmHg (NS). Sentron BP under N fell from 158 +/- 17/96 +/- 8 mmHg to 148 +/- 13/90 +/- 7 mmHg (p less than 0.001/p less than 0.01) with no BP change under P (152 +/- 12/93 +/- 7 mmHg to 151 +/- 14/93 +/- 8 mmHg NS). BP recorder every 30 min for 12 hours revealed a decrease under N (160 +/- 18/105 +/- 10 mmHg to 142 +/- 16/94 +/- 10 mmHg; p less than 0.001/p less than 0.001) with a placebo effect in the control group on the diastolic BP (160 +/- 15/103 +/- 7 mmHg to 156 +/- 16/100 +/- 8 mmHg/NS/p less than 0.05).(ABSTRACT TRUNCATED AT 250 WORDS)     

Ambulatory monitoring predicts development of drug-treated hypertension in subjects with high normal blood pressure

BACKGROUND: High normal blood pressure (HNBP), i.e. blood pressure (BP) > or = 130/85 mmHg and <140/90 mmHg, is an important predictor of progression to established hypertension. DESIGN: The purpose of this retrospective study was the evaluation of the predictive value of ambulatory blood pressure monitoring (ABPM) for the development of drug-treated hypertension in subjects with HNBP and other risk factors. METHODS: We studied 127 subjects (69 M, 58 F, age 50 +/- 14 years): 59 subjects had normal BP (NBP: < 130/85 mmHg), 68 subjects had systolic and/or diastolic HNBP. All the subjects underwent ABPM. There were 21/68 (30.9%) subjects in the HNBP group vs. 1/59 (1.7%) in the NBP group with an elevated (>135/85 mmHg) daytime ambulatory blood pressure (ABP) (p < 0.01). RESULTS: After an average follow-up of 103 +/- 28 months, 27 subjects (39.7%) in the HNBP group and 4 subjects (6.8%) in the NBP group developed drug-treated hypertension (p < 0.01). An elevated daytime ABP correctly predicted development of drug-treated hypertension in 17/21 subjects (81%) of the HNBP group and in the only subject of the NBP group. Development of drug-treated hypertension was associated with higher office and ambulatory BP (p < 0.01) and pulse pressures (p < 0.05), longer follow-up (p < 0.05) and higher prevalence of hypercholesterolaemia and smoking (p < 0.01). CONCLUSIONS: We conclude that ABPM correctly predicts development of drug-treated hypertension in most subjects who were identified early as having a daytime mean ABP >135/85 mmHg. ABPM appears to be a useful clinical tool in the early diagnosis of hypertension in subjects with metabolic risk factors and smoking.     

Study of representative periods of day-time and night-time levels of blood pressure

The aim of this study is to assess whether it is possible to shorten ambulatory blood pressure (ABP) monitoring while getting measurements that precisely reflect 24 hours and daytime blood pressure (BP). METHODS: three hundred and thirty six young male subjects aged: 21 +/- 2 y, height: 178 +/- 7 cm, weight, 75 +/- 12 kg, with normal or "borderline" BP (casual BP: 138 +/- 13/79 +/- 8 mmHg) participated in the study. BP was recorded in each, every 15 minutes on 24 hours with a Spacelabs 5200 device. Systolic and diastolic BP on 24-h, during the 9 a.m. - 8 p.m. period (daytime) and BP related to the different subperiods included between 15 minutes and 6 hours were calculated. BP values obtained from the 196 subperiods were correlated with 24-h, daytime ABP and causal BP. Results were classified according to the value of correlation coefficient, slope and intercept of regressions. RESULTS: no subperiod accurately predict 24-h systolic BP (SBP) or diastolic BP (DBP) (the best correlation are established with the subperiods: 7 p.m.-01 a.m. for SBP; r = 0.916, p less than 10(-9), y = 0.76 x + 30; and 06 a.m.-12 a.m. for DBP; r = 0.914, p less than 10(-9), y = 0.87 x + 9). Four 6 hours subperiods sampled between 09 a.m.-3 p.m. and 12 a.m.-6 p.m. predict alike and in a reasonable way the daytime BP (SBP: r = 0.971, p less than 10(-9), y = 0.94 x + 8; r = 0.973, p less than 10(-9), y = 0.91 x + 7. Best correlations with casual BP are moderate (SBP: r = 0.674, DBP: r = 0.588). COMMENTS: BP measurements of subperiods smaller or equal to 6 hours cannot accurately predict the average 24-h BP. This is related mainly to the night-time/daytime BP fluctuations. Daytime BP can be estimated with short-term monitoring but the duration must not be smaller than 6 hours.     

Identification of subjects with white-coat hypertension and persistently normal ambulatory blood pressure

OBJECTIVE: To assess the spontaneous changes in clinic blood pressure, ambulatory blood pressure (ABP) and left ventricular structure in untreated subjects with white-coat hypertension (WCH). DESIGN: A prospective observational study. PATIENTS AND METHODS: In 83 untreated subjects with WCH, 24 h non-invasive ABP monitoring and echocardiographic studies of the left ventricle were repeated after 0.5-6.5 years (mean 2.5) in the absence of antihypertensive drug treatment. WCH was defined by an average daytime ABP < 131/86 mmHg in women and < 136/87 mmHg in men. Ambulatory hypertension was defined by higher ABP values. RESULTS: In the whole population, the clinic blood pressure, ABP and left ventricular mass did not change from baseline to the follow-up visit, whereas the peak A: peak E ratio (where A is the velocity of transmitral blood flow after atrial contraction and E is the velocity during passive left ventricle filling) increased from 0.86 to 0.93. Sixty-three per cent of subjects remained in the WCH category at follow-up study; the remaining 37% shifted to the ambulatory hypertension category. The former group showed no changes in clinic blood pressure, ABP, left ventricular mass and peak A: peak E ratio. The clinic blood pressure of those who developed ambulatory hypertension did not change, whereas their ABP and peak A: peak E ratio increased and their left ventricular mass increased slightly but not significantly. The left ventricular mass increased from baseline to follow-up study by 6.2% in those who developed ambulatory hypertension and decreased by 1.6% in those who remained in the WCH category. The changes in left ventricular mass were associated with the changes in average 24 h systolic blood pressure, but not with the changes in clinic blood pressure. In a stepwise logistic regression analysis, average daytime diastolic blood pressure was the sole variable to enter the model and the probability of ambulatory hypertension at follow-up study was 20.0%percnt; in those with basal daytime ABP <130/80 mmHg, versus 81% in those with higher basal daytime blood pressure levels. CONCLUSION: After 0.5-6.5 years, WCH spontaneously evolved into ambulatory hypertension in 37% of subjects, with an accompanying rise in left ventricular mass. The probability of ambulatory hypertension increased with the baseline values of ABP, rather than with those of clinic blood pressure. WCH might be a prehypertensive state (particularly in subjects with higher baseline ABP levels) and should be defined by low levels of daytime ABP, possibly lower than 130/80 mmHg.     

Circadian rhythm of blood pressure in patients with obstructive sleep apnea.

AIMS: The aims of this study were to examine the circadian variation in blood pressure (BP) in obstructive sleep apnea (OSA) and to compare this between normotensive and hypertensive subjects. METHODS: We measured 24-hour ambulatory BP (ABP) in 72 men (mean age 51 +/- 8 years), with OSA diagnosed on overnight sleep study. Measurements of BP were made at 15 min intervals for 24 h using either an Oxford Medilog ABP or Spacelabs 90207 recorder. All recordings were performed after > or = 3 week washout of anti-hypertensive drugs. The day-time monitoring period was defined as 07:00 hrs to 22:00 and night-time 22:00 to 07:00. The ratio of night:day systolic and diastolic BP was calculated. RESULTS: The patients were obese (mean body mass index 33 +/- 5 kg/m2) with a central pattern of obesity (waist:hip ratio 0.99 +/- 0.14, normal < 0.94). The mean 24-h ABP (systolic/diastolic) was 138 +/- 18/88 +/- 12 mmHg. The mean daytime ABP was 143 +/- 18/93 +/- 12 and night-time ABP 128 +/- 20/80 +/- 12 Hg. The night:day BP ratio was 0.90 +/- 0.07 (systolic) and 0.87 +/- 0.09 (diastolic) indicating that average BP was lower during the night. This pattern was similar in normotensive and hypertensive subjects. In contrast there was a significant relationship between increasing BMI and night:day blood pressure ratio (r = 0.56, p < 0.001) independent of the effects of OSA. CONCLUSION: In contrast to previous studies, men with OSA have a normal diurnal pattern of blood pressure levels. These findings suggest that any influence of OSA on BP is manifested throughout the 24-h period.     

A study on 24-hour ambulatory blood pressure in normotensive elderly, living in a local home for the aged]

Ambulatory blood pressure (BP) was non-invasively monitored in 124 normotensive elderly, living in an old people's home at the annual health examination. Cases were divided into 41 cases < 75 years (group A, mean age 70.6) and 83 cases > or = 75 years (group B, 82.7) for analysis of the office BP and 24-hour BP. Whole-day systolic BP in group B was significantly higher than those in the group A (p < 0.02) although no significant differences were observed in diastolic BP and pulse rate. Separated analysis of whole-day BP into daytime and nighttime revealed that the nighttime systolic BP in the group B was significantly higher than those in group A (132.2 +/- 17.4% vs. 123.8 +/- 18.6 mmHg, p < 0.02) whereas no significant difference was observed in day-time systolic BP between two groups (136.6 +/- 14.9 vs. 132.1 +/- 14.4 mmHg, n.s.). The day-night difference in systolic BP tended to be less in group B than in group A (4.5 +/- 11.6 vs. 8.2 +/- 12.2 mmHg, p < 0.10). The prevalence of non-dippers, who had a higher nighttime systolic BP than daytime systolic BP were 24.4% of the group A and 30.1% of the group B. It was concluded that systolic BP during the nighttime increased with the ageing process after age 60, although that during daytime did not change.     

Blood pressure on arising, morning blood pressure surge and blood pressure variability in white coat hypertensives and in matched normotensives and sustained hypertensives.

INTRODUCTION: It is still controversial whether subjects with white-coat hypertension (WCHT) exhibit higher cardiovascular risk compared to normotensive subjects (NT). In subjects with WCHT it is not known whether the abnormal blood pressure (BP) reaction in the office also occurs at other times of day, particularly on arising and immediately after waking, i.e. the times at which the majority of cardiovascular events are reported to occur. OBJECTIVE AND METHODS: To evaluate with 24h ambulatory BP measurement the values of morning BP surge, BP on arising and BP variability in subjects with WCHT in comparison with age-, gender- and weight-matched normotensives (BP) and untreated sustained hypertensives (BP). RESULTS: Groups of BP, WCHT and BP were matched for age, gender and body weight: BP: n=69, age 49 +/- 7 years, 54 % female, BMI 26 +/- 1, casual BP 126/79 +/- 5/4 mmHg, daytime BP 124/80 +/- 6/6 mmHg; WCHT: n=74, age 52 +/- 8 years, 57% female, BMI 26 +/- 2, casual BP 152/95 +/- 7/7 mmHg, daytime BP 126/80 +/- 5/6 mmHg; HT: n=79, age 53 +/- 7 years, 56% female, BMI 27 +/- 2, casual BP 154/97 +/- 9/8 mmHg, daytime BP 143/89 +/- 12/10 mmHg. Of the three groups, subjects with WCHT exhibited BP on arising (121/81 +/- 13/8 mmHg) similar to that of NTs (120/80 +/- 13/9 mmHg, NS), both significantly lower than that of HTs (137/92 +/- 17/10 mmHg, p < 0.01), suggesting the absence of an alerting BP reaction in WCHT at that time. By contrast, subjects with WCHT showed higher values of systolic morning BP surge vs. NTs (25 +/- 10 vs. 22 +/- 11 mmHg, p < 0.05), both lower than that observed in hypertensives (33 +/- 11 mmHg, p < 0.01 vs. NT and WCHT) and greater daytime variability (systolic BP standard variation), i.e. 12 2 vs. 10 +/- 2 mmHg, p < 0.05, both lower than that observed in hypertensives (14 +/- 3 mmHg, p < 0.01 vs. NT and WCHT). CONCLUSIONS: Although subjects with WCHT did not show any alerting blood pressure reaction on arising, morning BP surge and BP variability were greater in these subjects than in control normotensives, although lower than sustained hypertensives. Although this is still speculative, we cannot exclude the possibility that even a slight increase in morning BP surge might in the long term constitute an additional load on the circulation that could increase cardiovascular risk in subjects with WCHT compared to matched normotensives.     

Effects of doxazosin on ambulatory blood pressure and sympathetic nervous activity in hypertensive Type 2 diabetic patients with overt nephropathy.

AIMS: Few studies have reported the effect of alpha(1)-adrenergic antagonists on 24-h blood pressure (BP) and sympathetic nervous activity in hypertensive patients with diabetic nephropathy. We assessed the effects of doxazosin on 24-h BP and spectral analysis of heart rate variability in hypertensive Type 2 diabetic patients with macroalbuminuria and compared the results with those in hypertensive Type 2 diabetic patients with normoalbuminuria and non-diabetic patients with essential hypertension. METHODS: Thirty-three patients in the macroalbuminuric group, 24 patients in the normoalbuminuric group, and 34 patients with essential hypertension underwent ambulatory BP monitoring before and after doxazosin treatment. Spectral analysis was performed to calculate the high-frequency (HF) components, a marker of parasympathetic nervous activity, and the low-frequency (LF) components, a marker of sympathetic nervous activity. RESULTS: Doxazosin decreased waking (from 158 +/- 17/88 +/- 10 to 148 +/- 15/80 +/- 7 mmHg, P = 0.001 for systolic and P < 0.001 for diastolic BP) and sleeping BP (146 +/- 20/79 +/- 10 to 137 +/- 17/72 +/- 9 mmHg, P < 0.001 and P < 0.001) in the macroalbuminuric group, but only decreased waking BP in the essential hypertension group (157 +/- 16/91 +/- 9 to 145 +/- 15/84 +/- 11 mmHg, P < 0.001 and P < 0.001) and normoalbuminuric group (159 +/- 15/89 +/- 9 to 150 +/- 16/82 +/- 10 mmHg, P = 0.014 and P < 0.001). Doxazosin decreased waking (from 1.48 +/- 0.11 to 1.42 +/- 0.12, P = 0.001) and sleeping (1.46 +/- 0.11 to 1.40 +/- 0.13, P = 0.001) LF components [unit: log(ms(2)/Hz)] only in the macroalbuminuric group without changing HF components. The normoalbuminuric and essential hypertension groups showed no differences (P = 0.637 and 0.492) in LF components during sleep. CONCLUSIONS: Doxazosin may be an antihypertensive agent that decreases both waking and sleeping BP through inhibiting sympathetic nervous activity in macroalbuminuric diabetes patients.     

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.     

Nurse-recorded and ambulatory blood pressure predicts treatment-induced reduction of left ventricular hypertrophy equally well in hypertension: results from the Swedish irbesartan left ventricular hypertrophy investigation versus atenolol (SILVHIA) study

OBJECTIVE : To compare the relationships of treatment-induced reductions of left ventricular hypertrophy to the changes in clinic and ambulatory blood pressure (BP). DESIGN : Double-blind and randomized treatment with irbesartan or atenolol for 48 weeks. PATIENTS : Patients with hypertension and left ventricular hypertrophy (n = 66) with a seated diastolic BP 90-115 mmHg (average of three measurements one minute apart by nurses). MAIN OUTCOME MEASURES : Registrations of echocardiographic left ventricular (LV) mass. Clinic and ambulatory BP. RESULTS : In the total material, nurse-measured BP was reduced by 23 +/- 15/16 +/- 7.7 mmHg and 24-h ambulatory BP fell 20 +/- 15/14 +/- 8.5 mmHg by treatment. The correlation between the change in nurse-measured BP and LV mass index (LVMI) induced by treatment was r = 0.35, P = 0.004 for systolic BP and r = 0.26, P = 0.03 for diastolic BP. Corresponding values for 24-h ambulatory BP were r = 0.29, P = 0.02 and r = 0.35, P = 0.004, respectively, with similar correlations for day- and night-time ambulatory BP. The nurse-recorded BP was slightly higher than ambulatory BP (systolic clinic - systolic 24-h ambulatory BP = 5 mmHg). Using 130/80 mmHg as a cut-off value for normal 24-h ambulatory BP, eight subjects had normal diastolic or systolic ambulatory BP, or both. Interestingly, these patients also experienced LVMI regression following treatment (low/normal ABP, -13 +/- 21 g/m2; remaining patients, -18 +/- 22 g/m2, P > 0.5). CONCLUSIONS : In patients with hypertension and left ventricular hypertrophy, ambulatory BP is not superior to carefully standardized nurse-recorded seated BP in terms of associations with treatment-induced changes in LV mass.     

Expedited blood pressure control with initial angiotensin II antagonist/diuretic therapy compared with stepped-care therapy in patients with ambulatory systolic hypertension

OBJECTIVES: The present study investigated whether initiating therapy with a combination of losartan (L) and hydrochlorothiazide (HCTZ) allows for faster blood pressure (BP) control and fewer medications than the usual stepped-care approach in patients with stage 2 or 3 hypertension and ambulatory systolic hypertension. METHODS: Patients with a mean daytime systolic ambulatory BP (ABP) of 135 mmHg or higher were randomly assigned to receive L 50 mg plus HCTZ 12.5 mg titrated to L 100 mg plus HCTZ 25 mg versus HCTZ 12.5 mg plus atenolol 50 mg. Amlodipine 5 mg was then added, if needed, to achieve a BP goal of less than 130 mmHg. Treatment titration was based on ABP. RESULTS: Significantly more patients randomly assigned to L/HCTZ (63.5%) than stepped-care (37.5%; P=0.008) achieved the primary end point (daytime systolic BP of less than 130 mmHg). Initial L/HCTZ induced significantly greater decreases in ABP during each 24 h period after six weeks of therapy. Although reductions in systolic and diastolic ABP were not statistically different at the end of the study, ABP reduction was significantly greater (P<0.001) with the L/HCTZ-based regimen. Twice as many patients in the L/HCTZ group achieved the goal ABP with no more than two drugs (30.0% versus 14.7%; P=0.03). Moreover, tolerability was significantly better (P=0.006) in the L/HCTZ group, with a 40.0% incidence of adverse events, versus 65.6% in the stepped-care group. CONCLUSION: Initiating antihypertensive therapy with the combination of L/HCTZ in patients with stage 2 or 3 hypertension and ambulatory systolic hypertension reaches a target BP faster in a higher proportion of patients, with fewer adverse events and less need for a third drug regimen than the conventional stepped-care approach.     

Chronobiological analysis by ambulatory blood pressure monitoring of the hyperbaric and hypobaric indexes for evaluation of the antihypertensive effect of long-acting nifedipine.

BACKGROUND: It has been suggested that chronobiology can provide new insights into the evaluation and treatment of cardiovascular disease. In the present study the hyperbaric index (hyperBI) and hypobaric index (hypoBI) were compared with the mean blood pressure (BP) over 24 h to evaluate the antihypertensive effect of long-acting nifedipine on essential hypertension. METHODS AND RESULTS: Fourteen patients were treated with nifedipine CR (20-40 mg/day) for 6 months. Ambulatory BP monitoring was performed before and after treatment. The hyperBI (mmHg . h/day) was calculated as the integrated BP area above the conventional upper limit (140/90 mmHg for the daytime and 120/80 mmHg at night), and the hypoBI was calculated as the integrated BP area below the conventional lower limit (110/60 mmHg for the daytime and 100/50 mmHg at night). At baseline, both the systolic and diastolic 24-h hyperBI values closely correlated with the 24-h mean BP (r=0.994 and 0.935, p<0.0001). Treatment with nifedipine significantly lowered both the 24-h mean systolic and diastolic BP (143+/-14/89 +/-12 to 124+/-16/80+/-8 mmHg, p<0.001/p=0.001), as well as the casual BP (167+/-11/101 +/-8 to 140+/-13/86+/-10 mmHg, p<0.001/p<0.01). Reduction of both the systolic and diastolic hyperBI values was statistically significant over the 24-h period (274+/-266 to 90+/-155, p=0.009; 145+/-187 to 41+/-63, p=0.024), as well as during the daytime (200+/-181 to 66+/-116, p=0.014; 105+/-120 to 24+/-38, p=0.017) and at night (systolic, 74+/-106 to 24+/-52, p=0.021). The 24-h mean BP was normalized, but a small excess BP load persisted despite treatment. There was no significant increase of systolic hypoBI during the 24-h period (1+/-2 to 25+/-30, p=0.065), the daytime (0+/-0 to 14+/-38, p=0.20), or at night (1+/-3 to 11+/-19, p=0,052). Similar findings were obtained for diastolic hypoBI. CONCLUSIONS: Nifedipine CR improved the 24-h hyperBI and mean BP without causing excessive hypotension. These 2 parameters have a close relationship when assessment is done by 24-h BP monitoring. The hyperBI and hypoBI may assist in providing adequate antihypertensive therapy for individual patients by detecting an excessive BP load or hypotension, respectively.     

Effects of GH replacement on 24-h ambulatory blood pressure and its circadian rhythm in adult GH deficiency

OBJECTIVE: Increased prevalence of hypertension and cardiovascular mortality have been reported in hypopituitary patients who had been appropriately replaced with conventional pituitary hormones except GH. Growth hormone replacement (GHR) results in improvement of surrogate markers of cardiovascular function. Data on effects of GHR on blood pressure (BP) in adult growth hormone deficiency (AGHD), however, remain contradictory. There are as yet no reports on BP circadian rhythms in untreated or treated AGHD. Therefore, in a 12-month follow-up study, we evaluated the effects of GHR on ambulatory blood pressure (ABP) in AGHD patients. STUDY DESIGN: A prospective, open treatment design study to determine the effects of GHR on ABP and heart rate in AGHD patients. GH was commenced at a daily dose of 0.5 IU, and titrated up by increments of 0.25 IU at 4-weekly intervals to achieve and maintain IGF-I standard deviation score (IGF-I SD) between the median and upper end of the age-related reference range. PATIENTS: Twenty-two, post-pituitary surgery, severe AGHD patients (11 men), defined as peak GH response < 9 mU/l to provocative testing were recruited. The mean age +/- SEM was 48.8 +/- 2.5 years. Twenty-one patients required additional pituitary replacement hormones following pituitary surgery and were on optimal doses at recruitment. MEASUREMENTS: Twenty-four-hour ABP and heart rate (HR), body mass index (BMI), waist hip ratio (WHR) and total body water (TBW) were measured before and after 12 months on GHR. Cosinor analysis was used to analyse BP and HR circadian rhythm parameter estimates. RESULTS: Target IGF-I SD was achieved within 3 months of commencement of GHR in all patients (-3.5 +/- 0.4 at baseline vs. 0.8 +/- 0.2 at 3 months, P < 0.001) and remained within range at 12 months (1.1 +/- 0.2, P < 0.001 compared to baseline). A significant increase in TBW (45.8 +/- 1.2 vs. 47.8 +/- 1.5 kg, P < 0.05) but no significant change in BMI (30.7 +/- 2.2 vs. 31.8 +/- 2.7, P = NS) or WHR (0.95 +/- 0.02 vs. 0.93 +/- 0.02, P = NS) was observed after 12 months on GHR. The 24-h mean systolic ABP (SBP; 126.2 +/- 2.8 vs. 120.1 +/- 2.7 mmHg, P < 0.001) and diastolic ABP (DBP; 78.2 +/- 1.6 vs. 71.4 +/- 1.8 mmHg, P < 0.001) significantly decreased following GHR with a parallel increase in 24-h mean HR (69.6 +/- 2.5 vs. 73.8 +/- 2.5 beats/min; P < 0.001). A significant nocturnal decrease in SBP and DBP was observed both before (SBP; daytime, 129.1 +/- 2.8 vs. night time, 115.9 +/- 3.0 mmHg, P < 0.001 and DBP; daytime, 80.7 +/- 1.6 vs. night time, 69.2 +/- 1.8 mmHg, P < 0.001) and following GHR (SBP; daytime, 122.8 +/- 2.6 vs. night time, 110.0 +/- 3.6 mmHg, P < 0.001 and DBP; daytime, 73.9 +/- 1.8 vs. night time, 62.0 +/- 2.3 mmHg, P < 0.001). Individual and population-mean cosinor analysis demonstrated significant circadian rhythms for SBP, DBP and HR before and after 12 months on GHR (P < 0.001), suggesting that SBP, DBP and HR circadian rhythms were not altered by GHR. There was, however, a significant reduction in SBP (124.2 +/- 2.8 vs. 118.4 +/- 2.8 mmHg, P < 0.001) and DBP (77.0 +/- 1.6 vs. 70.2 +/- 1.8 mmHg, P < 0.001) MESOR with an increase in HR MESOR (68.9 +/- 2.5 vs. 72.2 +/- 2.4 beats/min, P < 0.01) following GHR. CONCLUSIONS: Systolic and diastolic BP and HR circadian rhythms are preserved in AGHD following 12 months of GHR. However, there is a significant decrease in 24-h mean SBP and DBP and increase in 24-h mean HR after 12 months on GHR. We postulate that this decrease in 24-h mean SBP and DBP may result in a reduction of cardiovascular morbidity and mortality and may explain the beneficial effects of GHR on cardiovascular system previously reported in AGHD patients.     

Left ventricular hypertrophy in treated hypertensive patients with good blood pressure control outside the clinic,but poor clinic blood pressure control

OBJECTIVE: The aim of the study was to evaluate the prevalence of left ventricular hypertrophy (LVH) in treated patients with good blood pressure (BP) control during multiple home BP (HBP) measurements and during 24-h ambulatory BP monitoring (ABPM), but with unsatisfactory BP control in the clinic. These patients were compared with treated hypertensives whose BP was well controlled under the three circumstances. METHODS: Seventy-two treated consecutive patients (group I, age 56 +/- 10 years) with clinic BP values > or = 140/90 mmHg, and a difference between clinic and self-measured HBP > 10 mmHg for diastolic blood pressure (DBP) and/or > 20 mmHg for systolic blood pressure (SBP), underwent the following procedures: (1) clinic BP measurement; (2) routine diagnostic work-up; (3) HBP monitoring; (4) 24-h ABPM; (5) echocardiography. Thirty-five hypertensive patients with satisfactory BP control according to clinic (< 140/90 mmHg), HBP (< or = 131/82 mmHg) and ABP criteria (< or = 125/79 mmHg) were included as the control group (group II, age 55 +/- 9 years). RESULTS: In group I, 33 subjects out of the 72 (46%) with clinic BP > 140/90 mmHg had BP values controlled outside the clinic (23 according to HBP criteria and 22 according to ABP criteria). The prevalence of LVH (LV mass index > 134 g/m2 in men and > 110 g/m2 in women) was significantly higher in these patients (15.1 versus 2.8%, P < 0.01) than in group II (BP also controlled in the clinic), despite the fact that HBP and ABP were reduced to similar levels in the two groups. CONCLUSIONS Our data provide evidence that treated hypertensive patients with good BP control at home or during ambulatory monitoring, but incomplete BP control in the clinic, have more pronounced cardiac alterations than patients with both clinic and out of the clinic BP control. This finding offers a new piece of information about the diagnostic value of BP measurement in the clinic to assess BP control during antihypertensive treatment.