白大衣高血压患者的血小板功能

目的:探讨白大衣高血压(WCH)患者的血小板功能.方法:选初诊的原发性高血压(EH)患者、 WCH 患者、正常血压(NT)者各35例,通过诊室血压测量和24 h动态血压监测,同时测定并比较3组血小板最大聚集率(PAGTmax)、血浆血小板α-颗粒膜蛋白(GMP-140)含量、平均血小板容积(MPV) 、血小板数量的变化.结果:和NT对照组相比,EH组和WCH组 PAGTmax、血浆血小板GMP-140含量、MPV均明显增加(P<0.05)而三组血小板计数无统计学差异,同时EH组的PAGTmax、血浆血小板GMP-140含量、MPV均高于WCH组(P<0.05).EH组和WCH组MPV与24 h平均舒张压、GMP-140含量均正相关( P<0.05).结论:WCH存在血小板活化,可能和心血管事件发生率增加有关.     

Target organ damage and changes in arterial compliance in white coat hypertension. Is white coat innocent?

The aim of this study was to perform an extensive evaluation of target organ status, metabolic abnormalities and hemodynamic alterations in white coat hypertension (WCH). Fifty normotensive (NT), 90 WCH (ambulatory daytime blood pressure < 135/85 mmHg) and 101 hypertensive (HT) subjects underwent extensive biochemical, echocardiographic, fundoscopic examination. In a subgroup study, arterial compliance and intima-media thickness (IMT) were measured by Doppler ultrasound in left common carotid artery. WCH subjects were found to have higher body mass index (BMI) than the NTs (p = 0.042). Left ventricle mass index (LVMI) was greater in the WCHs than the NTs (p < 0.001), but significantly less than the HTs (p < 0.001). Hypertensive retinopathy was observed in the WCHs, but was less severe and rare compared to the HTs (13% vs 27%). Both WCHs and HTs had high levels of urinary albumin excretion (UAE) (p = not significant). Total cholesterol was higher in WCHs than in the NTs (p = 0.04) The distensibility coefficient (DC) of the WCHs was significantly greater than the HTs (p < 0.01), while significantly smaller than the NTs (p < 0.01). The compliance coefficient (CC) of the WCHs was significantly higher than the HTs (p < 0.01), and significantly less than the NTs (p < 0.01). The IMT in the HTs was significantly higher than the WCHs (0.81 +/- 0.05 vs 0.70 +/- 0.04 mm; p < 0.001) and the NTs (p < 0.001). The difference between the NTs and the WCHs was not significant. Our data indicate that patients with WCH represent an intermediate group between NTs and sustained HTs where target organ damage and cardiovascular risk is concerned.     

Increased circulating concentrations of asymmetric dimethylarginine (ADMA) in white coat hypertension

Elevated plasma levels of the endogenous nitric oxide (NO) synthase inhibitor asymmetric dimethylarginine (ADMA) contribute to endothelial dysfunction and seem to be a predictor for cardiovascular mortality. Elevated ADMA plasma concentrations have been demonstrated in patients with hypertension. However, the plasma concentrations of ADMA in white coat hypertension (WCH) has not been previously studied. The aim of this study was to evaluate ADMA in WCH and compare with normotensive (NT) and hypertensive (HT) patients. We also evaluated the relation between ADMA and NO in these three groups. For this purpose, 34 NT, 34 white coat hypertensive (clinical hypertension and ambulatory daytime blood pressure <135/85 mmHg) and 34 HT patients were recruited in this study. The subjects were matched for age, gender, body mass index (BMI) and the patients with smoking habit, dyslipidaemia and diabetes mellitus were excluded. The ADMA levels were determined by high performance liquid chromatography. Plasma ADMA levels were significantly higher in WCH group than in the NT group (3.21+/-0.49 micromol/l vs 2.84+/-0.58 micromol/l, P=0.046). It was significantly higher in the HT group than in the NTs (4.24+/-0.38 micromol/l, P<0.001). There was also a significant difference between the HT and WCH groups (P<0.001). The WCH subjects had significantly higher levels of NO than the HTs (41.68+/-2.23 vs 32.18+/-2.68 micromol/l; P<0.001) and significantly lower values than the NTs (48.24+/-4.29 micromol/l; P<0.001). In WCH and HT group, there was a negative correlation between ADMA and NO (r=-0.515, P=0.003 and r=-0.389, P=0.034, respectively). In NT subjects, there was no correlation between these two parameters (r=-0.287, P=0.124). The correlation between ADMA and NO was stronger in WCH group than in HT group. Although NO levels in HT patients were lower than WCHs and ADMA levels were higher in HT patients than WCHs, the negative correlation of these two parameters were more pronounced in WCH group. Decreased NO and increased ADMA levels in WCH may indicate endothelial dysfunction. Our data indicate also that WCH represent an intermediate group between NT and HT when endothelial dysfunction is concerned.     

Sequential follow-up clinic and ambulatory blood pressure evaluation in a low risk population of white-coat hypertensive patients and in normotensives

BACKGROUND: In subjects with white-coat hypertension (WCH) it is unclear how ambulatory blood pressure (ABPM) progresses over time and whether they exhibit an increased cardiovascular risk. METHODS: We prospectively evaluated the transition of clinic and ABPM values in 39 clinic and ABPM normotensive subjects (NT) (clinic BP<140/90 mmHg and awake BP<130/85 mmHg, ages 43.4+/-2.6 y) and in 79 untreated subjects (47.2+/-2.4 y) with WCH (clinic BP>140/90, awake ABP<130/85 mmHg) with no other major cardiovascular risk factors. Ambulatory blood pressure was evaluated at baseline and on at least two further occasions during follow-up. RESULTS: At baseline all subjects were untreated and groups did not differ on values of metabolic parameters, BMI, left ventricular mass index, and ABPM values. Subjects were revaluated for ABPM half way through and at the end of follow-up, 35+/-3 and 86+/-4 months in NT and 49+/-4 and 90+/-4 months in WCH. Thirty-six WCH were on antihypertensive treatment (AH) after baseline until the end of follow-up (WCH-tr), whereas 43 WCH (WCH-untr) were free from AH throughout the study. In a similar way all groups showed a significant (p<0.01) progressive increase in 24-h ABPM systolic blood pressure (SBP)/diastolic blood pressure (DBP) from baseline throughout the follow-up in NT (+4.9/2.1+/-0.8/0.9 mmHg), average annual increase of 0.72/0.37 mmHg/y, in WCH-tr (+ 5.0/1.2+/-1.1/1.5 mmHg), average annual increase of 0.66/0.31 mmHg/y and in WCH-untr (+5.4/3.2+/-0.9/1.1 mmHg), average annual increase of 0.74/0.39 mmHg/y. During the follow-up office SBP/DBP (mmHg) significantly rose in NT (+5.7/3.9) but was reduced in WCH-tr (-7.8/5.2) and in WCH-untr (-4.7/1.1). Development of ambulatory hypertension (daytime BP >130 and/or >85 mmHg) occurred in 15.4% (6/39) of NT, in 22.7% (8/36) of WCH-tr and in 26.1% (11/43) of WCH-untr (NS). First cardiovascular events recorded were three in subjects with WCH and none in NT. CONCLUSIONS: After 7.4 years of follow-up, both the progressive increase in ABPM and the rate of transition to ambulatory hypertension in subjects with WCH (either treated or untreated), who were selected under strict criteria were similar to that of normotensive subjects. Also there was no evidence that WCH exhibited a clear higher risk of development cardiovascular events.     

Cardiovascular prognosis of sustained and white-coat hypertension in patients with type 2 diabetes mellitus

OBJECTIVE: Cardiovascular prognosis in diabetic white-coat hypertension (WCH) has not yet been described. We designed this study to investigate the impact of WCH on cardiovascular events in patients with type 2 diabetes, compared with those having type 2 diabetes along with sustained hypertension (SH), and with nondiabetic hypertensive individuals. METHODS: We performed ambulatory blood pressure (BP) monitoring in 1207 consecutive hypertensive patients at baseline, and they were followed up for 49+/-22 months. The mean age was 70.7+/-9.8 years; 262 had type 2 diabetes; and 945 did not. They were classified as having SH with diabetes (n=210); diabetic WCH (n=52); SH alone (n=719); or WCH alone (n=226), using awake BP of 135/85 mmHg as the cutoff value. Cox regression models were used to calculate hazard ratios (HR) and 95% confidence intervals of the risk for cardiovascular events, after controlling for age, sex, body mass index, current smoking, serum creatinine, and clinical systolic BP. RESULTS: During the follow-up period, 97 cardiovascular events occurred. The incidence of cardiovascular events in the diabetic SH group was significantly higher than in the diabetic WCH, nondiabetic SH, and nondiabetic WCH (P<0.05; log-rank test) groups. In Cox regression analysis, the diabetic SH group had significantly higher risk of cardiovascular events compared with the diabetic WCH group (HR: 8.2; 95% confidence intervals: 1.09-61.8; P=0.04). Although nonsignificant, the HRs in the SH and WCH groups, relative to diabetic WCH, exceeded 3.0. CONCLUSIONS: The cardiovascular prognosis for diabetic WCH was better than that for diabetic SH during 4 years of follow-up.     

Prognostic significance of the white coat hypertension in patients with type 1 diabetes mellitus

Despite the high prevalence of white coat hypertension (WCH) in diabetes mellitus and the evidence that hypertension is a clear risk factor for the development of microalbuminuria (MA) in these patients, there is no information on the long-term prognostic significance of this condition in the diabetic population. We studied the evolution of 40 patients with type 1 diabetes mellitus (Type 1 DM). Twenty patients with WCH (office blood pressure> or =140/90mmHg associated with mean daytime blood pressure<135/85mmHg) classified as the WCH group and 20 patients with type 1 DM with a similar age and disease evolution, but who were normotensive, (office blood pressure<140/90mmHg associated with mean daytime blood pressure<135/85mmHg) classified as the normotensive control group. After 5 years of follow-up, MA appeared in four subjects and sustained hypertension in another, with a total of 31% of events in the WCH group, with none in the normotensive group. Kaplan-Meier analysis showed that the relative risk of developing these hypertensive events was 25% higher in the WCH group. At baseline, the night time systolic and diastolic blood pressure levels were significantly higher in patients who further developed MA and sustained hypertension. The findings in this study highlight the clinical importance of careful follow-up of type 1 diabetic patients with WCH.     

Hyperhomocysteinemia: an additional risk factor in white coat hypertension

The association between homocysteine and sustained hypertension (HT) has been studied. The aim of this study was to assess homocysteine levels in white coat hypertension (WCH) as an indicator of increased risk in the development of cardiovascular diseases. WCH was defined as clinical hypertension and a daytime ambulatory blood pressure of < 135/85 mmHg. Plasma levels of homocysteine were determined in patients with WCH, hypertension, and normotension (NT). The study group included 100 subjects, 33 with WCH (16 males, 17 females) aged 49.1 +/- 1.9; 35 sustained hypertensives (17 males,18 females) aged 48.5 +/- 1.7 and 32 normotensive control subjects (15 males, 17 females) aged 48.8 +/- 2.2. The subjects were matched for age, gender, and body mass index. Patients with a smoking habit, dyslipidemia, or diabetes mellitus were not included in the study. Homocysteine levels were analyzed by ELISA. Plasma homocysteine levels were significantly higher in the WCH group compared to the controls (12.32 +/- 1.07 versus 5.35 +/- 1.38 micromol/L; P < 0.001) and the WCH group had significantly lower homocysteine values than the hypertensives (19.03 +/- 0.76 micromol/L P < 0.001). Total cholesterol and tri-glycerides were not different among the groups. There were no statistically significant differences in urinary albumin excretion (UAE) or creatinine clearance between the three groups. Hypertensive retinopathy was observed in the WCH group, but was less severe and less frequent compared to HTs. LVMI was greater in the WCH group compared to the NTs, but significantly less than HTs. The data demonstrate that WCH is associated with high levels of homocysteine. The increase in homocysteine level in WCH is not as high as in SHT. Since an elevated plasma homocysteine level is a strong risk factor for coronary artery disease and there was target organ damage in our WCH group, we conclude that WCH should not be considered to be an innocent trait.     

Cardiovascular and renal events in uncomplicated mild hypertensive patients with sustained and white coat hypertension

BACKGROUND: The prognostic value of white coat hypertension (WCH) in uncomplicated patients with mild hypertension is not yet completely clear. We investigated cardiovascular outcomes in patients with mild hypertension and without left ventricular hypertrophy, diabetes mellitus, and associated cardiovascular and renal disease, with sustained hypertension (SH) and WCH. METHODS: The occurrence of fatal and nonfatal cardiovascular events was evaluated in 1038 patients with mild hypertension and 241 normotensive subjects. The presence of WCH was defined as clinic hypertension and daytime blood pressure <135/85 mm Hg. RESULTS: During follow-up (4.5 +/- 2.3 years, range 0.5 to 9.2 years) the event rates per 100 patient-years in subjects with normotension, WCH, and SH were 0.27, 0.38, and 1.39, respectively. After adjustment for other covariates, Cox regression analysis showed that SH was an independent predictor of cardiovascular events (SH versus WCH, RR 5.17, 95% CI 2.04 to 13.1, P = 0 .001), whereas there was no significant difference between normotension and WCH (normotension versus WCH, RR 0.93, 95% CI 0.22 to 3.98, P = .92). At the end of follow-up, drug therapy was less frequent and intensive in WCH than in SH. CONCLUSIONS: In this study of individuals with mild hypertension and without left ventricular hypertrophy, diabetes mellitus, and associated cardiovascular and renal disease, subjects with WCH, despite less frequent and intensive drug therapy, had a significantly better prognosis than those with sustained hypertension.     

Endothelium and angiogenesis in white coat hypertension

Hypertensive patients are at particular risk of cardiovascular complications, possibly related to endothelial damage or dysfunction, or to abnormal angiogenesis. The aim of this study was to compare the risk conferred by white coat hypertension (WCH) vs sustained hypertension in the development of the endothelial dysfunction and abnormal angiogenesis by evaluating nitric oxide (NO=NO2+NO3), endothelin-1 (ET-1), vascular endothelial growth factor (VEGF), and E-selectin levels in plasma. The study group included 102 subjects, 34 with WCH (17 male and 17 female patients) aged 49+/-11 years, 34 sustained hypertensives (HT) (15 male and 19 female patients) aged 47+/-11 years and 34 normotensive control subjects (NT) (16 male and 18 female patients) aged 48+/-10 years. WCH was defined as clinical hypertension and daytime ambulatory blood pressure less than 135/85 mmHg. The subjects were matched for age, gender, body mass index and the patients with smoking habit, dyslipidaemia, and diabetes mellitus were excluded from the study. The NO, ET-1, VEGF and E-selectin levels were analysed by ELISA technique. The WCH subjects had significantly higher levels of NO than the HT (41.68+/-2.23 vs 32.18+/-2.68 micromol/l; P<0.001) and significantly lower values than the NT (48.24+/-4.29 micromol/l; P<0.001). ET-1 levels of the WCH group were significantly higher than the NT (8.10+/-0.92 vs 5.95+/-0.26 ng/ml; P<0.001) and significantly lower than the HT (11.46+/-0.59 ng/ml; P<0.001). Considering with VEGF, the WCH group had significantly higher levels than the NT (195.88+/-11.84 vs 146.26+/-18.67 pg/ml; P<0.001), but the difference from the HT group was not significant (203.35+/-7.48 pg/ml; P=0.062). E-selectin in the WCH group was significantly lower than the HT (4.77+/-0.52 vs 8.49+/-2.85; P<0.001), but the difference from the NT group was not significant (3.86+/-0.67; P=0.077). Our data demonstrate that WCH is associated with endothelial dysfunction and abnormal angiogenesis. The degree of these changes is not as severe as observed in hypertensive population.     

白大衣高血压患者血压变异性对靶器官损害的影响

目的探讨血压变异性对白大衣高血压患者靶器官损害的影响。方法门诊患者119例,根据24 h动态血压和诊室血压分为正常血压组(NT)和白大衣高血压组(WCH)。其中白大衣高血压组根据24 h收缩压变异程度分为:白大衣高血压血压变异性低组(WCH-L),白大衣高血压血压变异性高组(WCH-H)。心脏和颈动脉超声检查:计算二尖瓣环心肌舒张早期峰值运动速度(Em)与舒张晚期峰值运动速度(Am)比值(Em/Am),评价左心室舒张功能及颈动脉损害的发生率。结果 (1)NT组左心室舒张功能减退发生率(21.87%,7例/32例)、颈动脉损害的检出率(18.75%,6例/32例)与WCH-L组(31.11%,14例/45例;22.22%,10例/45例)相近,组间差异无统计学意义(P=0.370、0.711);(2)WCH-H组左心室舒张功能减退发生率(52.38%,22例/42例)、颈动脉损害的检出率(42.85%,18例/42例)明显高于NT组(P=0.008、0.028)和WCH-L组(P=0.044、0.040),差异均有统计学意义。结论血压变异性较大的白大衣高血压患者具有较高的靶器官损害发生率。     

Investigation of major genetic polymorphisms in the Renin-Angiotensin-aldosterone system in subjects with young-onset hypertension selected by a targeted-screening system at university

Although polymorphisms in renin-angiotensin-aldosterone (RAA) system genes for angiotensinogen (AGT M235T), angiotensin-converting enzyme (ACE I/D), angiotensin II type 1 receptor (AT1 A/C1166), and aldosterone synthase (CYP11B2-344T/C) have been major targets for genetic investigation in association with essential hypertension (EH), the influence of these genetic factors is still to be determined. Because patients with young-onset EH are thought to possess a stronger genetic background than EH patients who show elevated BP relatively late in life, the targeted screening of hypertensive students in Tohoku University was completed for the selection of subjects for genetic investigation. Out of 16,434 students (12,794 males and 3,670 females) younger than 30, 22 students showed a high blood pressure (BP) (systolic and diastolic BP of 140 and/or 90 mmHg or greater, respectively, on two occasions and more than 135 and/or 85 mmHg, respectively, at a third measurement during casual BP measurements at the Tohoku University Health Center. These 22 students were asked to measure their BP at home (HBP). Six of the students had a systolic HBP of more than 135 mmHg and/or a diastolic HBP of more than 85 mmHg, and these students subsequently received medical examinations at Tohoku University Hospital and were diagnosed with EH. Genotyping for the four major genetic polymorphisms mentioned above was performed on the six students with EH and on 12 of the remaining 16 students whose HBP was within the normal range (white coat hypertension: WCH). Neither the EH nor the WCH students showed a different distribution of genotypes and allelic frequencies, compared to those found in the general Japanese population. Hence, the present study suggests that none of the major genetic polymorphisms in the RAA system strongly influence the onset of EH.     

Prognostic superiority of daytime ambulatory over conventional blood pressure in four populations: a meta-analysis of 7,030 individuals

OBJECTIVE: To investigate the multivariate-adjusted predictive value of systolic and diastolic blood pressures on conventional (CBP) and daytime (10-20 h) ambulatory (ABP) measurement. METHODS: We randomly recruited 7,030 subjects (mean age 56.2 years; 44.8% women) from populations in Belgium, Denmark, Japan and Sweden. We constructed the International Database on Ambulatory blood pressure and Cardiovascular Outcomes. RESULTS: During follow-up (median = 9.5 years), 932 subjects died. Neither CBP nor ABP predicted total mortality, of which 60.9% was due to noncardiovascular causes. The incidence of fatal combined with nonfatal cardiovascular events amounted to 863 (228 deaths, 326 strokes and 309 cardiac events). In multivariate-adjusted continuous analyses, both CBP and ABP predicted cardiovascular, cerebrovascular, cardiac and coronary events. However, in fully-adjusted models, including both CBP and ABP, CBP lost its predictive value (P >or= 0.052), whereas systolic and diastolic ABP retained their prognostic significance (P or= 0.21). In adjusted categorical analyses, normotension was the referent group (CBP < 140/90 mmHg and ABP < 135/85 mmHg). Adjusted hazard ratios for all cardiovascular events were 1.22 [95% confidence interval (CI) = 0.96-1.53; P = 0.09] for white-coat hypertension (>or= 140/90 and < 135/85 mmHg); 1.62 (95% CI = 1.35-1.96; P < 0.0001) for masked hypertension (< 140/90 and >or= 135/85 mmHg); and 1.80 (95% CI = 1.59-2.03; P < 0.0001) for sustained hypertension (>or= 140/90 and >or= 135/85 mmHg). CONCLUSIONS: ABP is superior to CBP in predicting cardiovascular events, but not total and noncardiovascular mortality. Cardiovascular risk gradually increases from normotension over white-coat and masked hypertension to sustained hypertension.     

白大衣高血压血管紧张素转换酶基因多态性分析

目的：研究白大衣高血压与血管紧张素转换酶（angiotensin converting enzyme，ACE）基因I／D多态性的关系。方法：应用多聚酶链式反应（PCR）方法对白大衣高血压，高血压病Ⅰ级患者和正常血压者各30例进行ACE I／D基因型检测，并分析比较。结果：白大衣高血压和高血压病Ⅰ级组Ⅱ基因型低于正常组（P〈0．01），白大衣高血压和高血压病Ⅰ级组DD基因型高于正常组（P〈0．01），白大衣高血压ID基因型显著高于高血压病Ⅰ级组和正常组（P〈0．01）。高血压病Ⅰ级组ID基因型低于正常组（P〈0．01）。结论：白大衣高血压与ACE基因多态性有关，ID基因型者易患白大衣高血压。     

Investigation of Major Genetic Polymorphisms in the Renin-Angiotensin-Aldosterone System in Subjects with Young-Onset Hypertension Selected by a Targeted-Screening System at University

Although polymorphisms in renin-angiotensin-aldosterone (RAA) system genes for angiotensinogen (AGT M235T), angiotensin-converting enzyme (ACE I/D), angiotensin II type 1 receptor (AT1 A/C¹¹⁶⁶), and aldosterone synthase (CYP11B2–344T/C) have been major targets for genetic investigation in association with essential hypertension (EH), the influence of these genetic factors is still to be determined. Because patients with young-onset EH are thought to possess a stronger genetic background than EH patients who show elevated BP relatively late in life, the targeted screening of hypertensive students in Tohoku University was completed for the selection of subjects for genetic investigation. Out of 16,434 students (12,794 males and 3,670 females) younger than 30, 22 students showed a high blood pressure (BP) (systolic and diastolic BP of 140 and/or 90 mmHg or greater, respectively, on two occasions and more than 135 and/or 85 mmHg, respectively, at a third measurement during casual BP measurements at the Tohoku University Health Center. These 22 students were asked to measure their BP at home (HBP). Six of the students had a systolic HBP of more than 135 mmHg and/or a diastolic HBP of more than 85 mmHg, and these students subsequently received medical examinations at Tohoku University Hospital and were diagnosed with EH. Genotyping for the four major genetic polymorphisms mentioned above was performed on the six students with EH and on 12 of the remaining 16 students whose HBP was within the normal range (white coat hypertension: WCH). Neither the EH nor the WCH students showed a different distribution of genotypes and allelic frequencies, compared to those found in the general Japanese population. Hence, the present study suggests that none of the major genetic polymorphisms in the RAA system strongly influence the onset of EH.     

Association between hypertensive urgencies and subsequent cardiovascular events in patients with hypertension

OBJECTIVE: To determine whether patients with hypertensive urgency have a higher risk for subsequent cardiovascular events compared with hypertensive patients without this event. METHODS: Overall, 384 patients with hypertensive urgency and 295 control patients were followed up for at least 2 years. Hypertensive urgency was defined as a systolic blood pressure above 220 mmHg and/or a diastolic blood pressure above 120 mmHg without any evidence of acute end-organ damage. The control group consisted of patients admitted to the emergency department with a systolic blood pressure between 135 to 180 mmHg and a diastolic blood pressure between 85-110 mmHg. The number of cardiovascular events defined as acute coronary syndrome, acute stroke, atrial fibrillation, acute left ventricular failure and aortic aneurysm were consecutively analyzed during follow-up. The median follow-up time was 4.2 years (interquartile range 2.9-5.7 years). Twenty-six patients of the urgency group and 23 patients of the control group were lost for follow-up. RESULTS: Overall, 117 (17%) patients had nonfatal clinical cardiovascular events and 13 had (2%) fatal cardiovascular events. The frequency of cardiovascular events was significantly higher in patients with hypertensive urgencies (88 vs. 42; P = 0.005). The Cox regression analysis identified age (P < 0.001) and hypertensive urgencies (P = 0.035) as independent predictors for subsequent cardiovascular events. CONCLUSIONS: Hypertensive urgencies are associated with an increased risk for subsequent cardiovascular events in patients with arterial hypertension.     

Characteristics of white coat hypertension in Chinese Han patients with type 2 diabetes mellitus

Objectives: This study documented the prevalence and clinical features of white coat hypertension (WCH) among Chinese Han patients with type 2 diabetes mellitus (T₂DM). Methods: Clinic and ambulatory blood pressure (BP) measurements were compared in 856 patients with T₂DM to determine the frequency of WCH (WCH was defined as clinical blood pressure ≥140/90?mmHg and daytime blood pressure <135/85?mmHg and/or 24-h ambulatory BP (ABP) mean value of <130/80?mmHg on ambulatory BP monitoring (ABPM). Weight, waist circumference (WC), body mass index (BMI), waist to height ratio (WHtR), fasting blood glucose, glycosylated hemoglobin level and circadian BP patterns were also measured to find clinical features predictive of WCH in T₂DM. Results: The prevalence of WCH was 7.36% (63/856) in the overall population, 6.13% (29/473) in male and 8.88% (34/383) in female (p?2DM, male WC were independent protective factors, whereas female sex, smoking and alcohol consumption were independent risk factors for WCH in T₂DM. Non-dippers and reverse dippers made up larger proportion of the WCH group (p?Conclusion: WCH is relatively common among T₂DM patients, it is a unique condition distinct from essential hypertension (EH), and WCH patients also exhibit significant differences in clinical parameters.     

Clinical Implications of White Coat Hypertension

Objective: To determine the clinical implications of mild white coat hypertension (WCH).

Subjects and methods: We studied 102 subjects (54 men, 48 women). 51 of whom were normotensive and 51 slightly hypertensive. None had ever received antihypertensive therapy. An ambulatory blood pressure (ABP) record (Accutracker II), a 24-h electrocardiogram and an echocardiogram were obtained from each, and each was examined by funduscopy. WCH subjects were compared with sustained hypertension (SH) subjects and with normotensives.

Results: Fifty-three percent of the hypertensives qualified as WCH. The ultrasonographic characteristics and the ABP variables of the WCH group differed significantly from those of normotensives, but not from those of the SH group. The prevalence of left ventricilar hypertrophy (LVH) in the SH group (62.5%) did not differ significantly from its prevalence in the WCH group (40.7%). but the prevalence among normotensives (17.6%) was significantly lower than in either of the other two groups. The WCH and SH groups did not differ significantly as regards the prevalence of hypertensive retinopathy (33.3%) in the former, 58.3% in the latter). For no non-LVH, nonretinopathic subject, whether norniotensive or hypertensive, were more than 18% of daytime diastolic ABP measurements ≥90mmHg. Ultrasonographic findings were no better correlated with ABP than with in-clinic BP measurements. Fundus findings correlated well with in-clinic BP and with numerous ABP parameters. Retinopathy, with or without LVH, was efficiently predictable among hypertensives on the basis of body mass index and the 24-h maximum of systolic BP.

Conclusions: Myocardiac remodelling and vascular retinopathy develop early and in parallel in hypertensives, and both developments appear to involve determinants including body mass index and 24-h maximum systolic BP. WCH subjects, as defined by current ABP-based criteria, have cardiac and retinovascular Characteristics different to normotensive subjects. Stricter criteria are needed to discriminate between hypertensives with and without the systemic developments that constitute the immediate source of risk to the hypertensive individual.     

Characteristics of young-onset hypertension identified by targeted screening performed at a university health check-up.

Since the prevalence and clinical characteristics of young-onset hypertension are still to be elucidated, we performed targeted-screening at an annual university health check-up for two consecutive years. Out of 16,464 subjects in 2003 and 17,032 in 2004 that were aged less than 30 years, 22 and 26 students (all males) exhibited high blood pressure (BP), respectively, on three occasions during casual BP measurements at the Tohoku University Health Center (systolic and diastolic BP of 140 and/or 90 mmHg or greater, respectively). These students were asked to measure their BP at home, and 9 subjects in total were diagnosed as having essential hypertension (EH). The remaining students were diagnosed as having white coat hypertension (WCH). In 8 out of 9 EH students, their father and/or mother had also been treated with antihypertensive medication. Adjustment by attendance ratio for each BP measurement suggested that the incidence of EH was around 0.1% and that of hypertension (EH and WCH) was around 0.5% in university students aged less than 25 years, since most of the subjects and hypertensive students were between 18 and 24 years old. Body mass index of the EH, which was more than 25 kg/m2 (overweight), was significantly higher than that with WCH. In conclusion, the combination of repeated casual BP measurements and home BP effectively identified young-onset EH. The clinical parameters indicated that male gender, genetic background, and excessive weight were risk factors for young-onset hypertension.     

Metabolic syndrome in subjects with white-coat hypertension: impact on left ventricular structure and function

Some reports have suggested that white-coat hypertension (WCH) is associated with some features of the metabolic syndrome (MetS). These metabolic disturbances, instead of WCH per se, may potentially explain the greater extent of end-organ damage sometimes observed in WCH subjects (WCHs) when compared to normotensive individuals (NTs). The aim of the present cross-sectional study was to compare left ventricular (LV) structure and function in three groups of subjects: WCHs with MetS, WCHs without MetS and NTs. A total of 145 WCHs, 35% of whom had MetS, were enrolled. As controls, 35 NTs were also studied. In all subjects, routine blood chemistry, echocardiographic examination and 24-h ambulatory blood pressure monitoring were performed. When compared with WCHs without MetS, those with MetS showed higher LV mass indexed by height elevated by a power of 2.7 (LVMH(2.7)) (49.6+/-14.8 vs 38.9+/-9.8 g/m(2.7); P<0.0001). The same parameter was greater in WCHs without MetS than in NTs (32+/-8 g/m(2.7); P=0.004). Moreover, the E-wave deceleration time was longer in WCHs with MetS than in those without it (236.2+/-66.4 vs 200.5+/-30.8 ms; P<0.0001). The relationship of MetS with LVMH(2.7) was confirmed in multivariate regression models. Our results seem to suggest that MetS may have a deleterious influence on LV structure and function in WCH. However, WCH, being associated with an increased LV mass, also in subjects without MetS, may not be considered as an innocuous phenomenon.     

Characteristics of young-onset white coat hypertension identified by targeted screening for hypertension at a university health check-up

Previously we estimated the prevalence of essential hypertension (EH) as around 0.1% and suggested that male gender, obesity, and strong genetic background (hypertension in parents) were risk factors for EH in a young population aged less than 30 based on targeted screening for hypertension at a university health check-up. This study also revealed a high incidence of white coat hypertension (WCH) in university students, and thus, we continued this screening for four consecutive years, and examined the prognosis and clinical characteristics of young-onset WCH. Three occasions of casual blood pressure (BP) measurement and additional home BP measurement revealed 72 WCH and 15 EH students (all males) during the 4-year study period. None of the WCH students had elevated home BP to the level of hypertension during their stay at university, and 26 out of 38 WCH students participating screening in the following years showed normal casual BP. Although WCH students showed a significantly higher pulse rate than controls, WCH could not be fully differentiated from EH either by pulse rate or by correlation between casual BP value and pulse rate. These findings indicate the requirement of longer follow-up after graduation to determine the prognosis of young-onset WCH, though EH and WCH in the young population share the same risk factors and, possibly, autonomic nervous system dysfunction. Since diagnosis of WCH has limited importance for university students, screening of EH following a general health check-up would elevate the clinical validity of casual BP measurement at the university.