Proportion of isolated clinical hypertension in primary care settings. Comparison of target organ damage in patients with isolated clinical hypertension and patients with sustained arterial hypertension

The aim of this study was to determine the proportion of isolated clinical hypertension (ICH) in newly diagnosed hypertensive patients, and to compare the incidence of target organ damage (TOD) in ICH and sustained hypertension patients. Participants. In a multi-centre study involving 14 primary care centres in Girona, Spain, 140 researchers recruited 214 newly diagnosed hypertensive patients 15-75 years of age, without history of cardiovascular events. Period of study. 2004-6. Method. Self-blood pressure monitoring (SBPM) and ambulatory blood pressure monitoring (ABPM). Evaluation. Anamnesis including blood pressure, physical examination and analysis (creatinine, albumin/creatinine index), electrocardiogram (left ventricular hypertrophy) and retinography (fundus damage). Results. In 129 (60.3%) subjects with sustained hypertension and 85 (39.7%) with ICH, no significant differences were found relative to gender, age, body mass index or blood pressure (155/90 vs 154/90 mmHg, respectively). Cholesterol levels were significant differences between both groups (5.97 mmol/l in sustained hypertension vs 5.64 mmol/l in ICH, p = 0.029). The proportion of ICH was approximately 40%. TOD incidence in sustained hypertensives was similar to that of ICH patients.     

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.     

Arterial hypertension, left ventricular hypertrophy and arrhythmias]

Arterial hypertension is the most common cause of chronic pressure overload of the left ventricle. Electrocardiographic and echocardiographic signs of left ventricular hypertrophy in hypertensive patients are associated with an increased cardiovascular mortality and incidence of sudden death habitually due to ventricular arrhythmias. The significance of a normal increase in systolic blood pressure during exercise in persons without evident resting hypertension is uncertain. M-mode and 2D echocardiography, 24-hour continuous ambulatory electrocardiographic (Holter), exercise testing and 24-hour ambulatory blood pressure monitoring (ABPM) were performed on 22 normotensive patients (group I); 25 normotensives with exaggerated blood pressure response to exercise (greater than 220 mmHg) (group II) and 33 hypertensive patients (group III). None was taking cardioactive drugs. Left ventricular hypertrophy (LVH) was found on one patient of group I (4.5%), 13 of group II (52%) and 20 of group III (61%). Left ventricular mass index (LVMI) was linearly correlated with maximum exercise blood pressure (group I: r2 = 0.518, p less than 0.0002; group II: r2 = 0.098, NS; group III: r2 = 0.407, p less than 0.0001) with 24-hour systolic pressure overload (ABPM) (group I: r2 = 0.848, p less than 0.0001; group II: r2 = 0.705, p less than 0.0001; group III: r2 = 0.839, p less than 0.0001) and 24-hour diastolic pressure overload (ABPM) (group I: r2 = 0.612, p less than 0.0001; group II: r2 = 0.815, p less than 0.0001; group III: r2 = 0.807, p less than 0.0001) within each group but not between different groups. The hypertensive subjects (group III) had a higher average heart rate (p less than 0.0001) more supraventricular premature (p less than 0.0001) and ventricular premature (p less than 0.0001) beats than the normotensive (group I) and normotensive patients with abnormal increases in systolic blood pressure response to exercise (group II) (p less than 0.0001) (NS) and (p less than 0.0002), respectively. LVMI was linearly correlated with ventricular premature beats (group I: r2 = 0.072, NS; group II: r2 = 0.823, p less than 0.0001; group III: r2 = 0.691, p less than 0.0001). Frequent and complex ventricular arrhythmias were more common in patients with LVH normotensives or hypertensives than without LVI (p less than 0.0001) and the age increases their severity. We conclude that normotensives with hypertensive response to exercise have similar incidence of LVI; if those patients develop sustained hypertension, LVI was previous to arterial hypertension. There are two types of hypertrophy: secondary hypertrophy is linked to the high afterload and vasoconstriction typical in hypertension.(ABSTRACT TRUNCATED AT 400 WORDS)     

Coronary flow velocity reserve is diminished in hypertensive left ventricular hypertrophy

BACKGROUND: Dipyridamole stress transesophageal echocardiography (STEE) is a feasible method for the evaluation of coronary flow velocity reserve (CFR). AIM: The aim of the present study was to investigate CFR in hypertensive patients with or without left ventricular hypertrophy (LVH). METHODS: The study comprised 73 patients with a negative coronary angiogram (29 men and 44 women). Three different groups were compared: normotensive patients, hypertensive patients without LVH and hypertensive patients with LVH. RESULTS: CFR was significantly decreased in patients with hypertension with LVH as compared to normotensive cases (2.19+/-0.50 vs 2.71+/-1.10; p<0.05). CFR of hypertensive patients without LVH was only slightly reduced as compared to normotensive cases (2.44+/-0.81 vs 2.71+/-1.10; p=ns). In hypertensive patients with LVH, the LV mass and LV mass index were inversely related to CFR (r = -0.481 and -0.477, p<0.05, respectively). CONCLUSIONS: CFR is diminished in patients with hypertension. The degree of CFR reduction is related to the extent of LVH.     

Comparison of three blood pressure measurement methods for the evaluation of two antihypertensive drugs: feasibility,agreement, and reproducibility of blood pressure response

Our objective was to compare three different methods of blood pressure measurement through the results of a controlled study aimed at comparing the antihypertensive effects of trandolapril and losartan. Two hundred and twenty-nine hypertensive patients were randomized in a double-blind parallel group study. After a 3-week placebo period, they received either 2 mg trandolapril or 50 mg losartan once daily for 6 weeks. At the end of both placebo and active treatment periods, three methods of blood pressure measurement were used: a) office blood pressure (three consecutive measurements); b) home self blood pressure measurements (SBPM), consisting of three consecutive measurements performed at home in the morning and in the evening for 7 consecutive days; and c) ambulatory blood pressure measurements (ABPM), 24-h BP recordings with three measurements per hour.Of the 229 patients, 199 (87%) performed at least 12 valid SBPM measurements during both placebo and treatment periods, whereas only 160 (70%) performed good quality 24-h ABPM recordings during both periods (P < .0001). One hundred-forty patients performed the three methods of measurement well. At baseline and with treatment, agreement between office measurements and ABPM or SBPM was weak. Conversely, there was a good agreement between ABPM and SBPM. The mean difference (SBP/DBP) between ABPM and SBPM was 4.6 ± 10.4/3.5 ± 7.1 at baseline and 3.5 ± 10.0/4.0 ± 7.0 at the end of the treatment period. The correlation between SBPM and ABPM expressed by the r coefficient and the P values were the following: at baseline 0.79/0.70 (< 0.001/< .0001), with active treatment 0.74/0.69 (0.0001/.0001). Hourly and 24-h reproducibility of blood pressure response was quantified by the standard deviation of BP response. Compared with office blood pressure, both global and hourly SBPM responses exhibited a lower standard deviation. Hourly reproducibility of SBPM response (10.8 mm Hg/6.9 mm Hg) was lower than hourly reproducibility of ABPM response (15.6 mm Hg/11.9 mm Hg).In conclusion, SBPM was easier to perform than ABPM. There was a good agreement between these two methods whereas concordance between SBPM or ABPM and office measurements was weak. As hourly reproducibility of SBPM response is better than reproducibility of both hourly ABPM and office BP response, SBPM seems to be the most appropriate method for evaluating residual antihypertensive effect.     

Comparison of demographic,clinical, laboratory parameters between patients with sustained normotension,white coat hypertension,masked hypertension,and sustained hypertension

BackgroundAfter measurement of office blood pressure (BP) and ambulatory BP monitoring (ABPM), 4 groups of patients were identified namely: (i) sustained normotensive patients (BPs are normal both clinically and by ABPM); (ii) white coat hypertensive patients (clinical BP were above limits, but ABPM were normal); (iii) masked hypertensive patients (clinical BP were normal, but ABPM were high); (iv) sustained hypertensive patients (both office and ABPM were high). The exact pathophysiologic mechanisms of these conditions are not exactly known. Besides in the literature there are only few studies that compare the 4 groups of patients together. Thus the study was carried out to compare patients with sustained normotension (SNT), white coat hypertension (WCHT), masked hypertension (MHT), and sustained hypertension (SHT).MethodsAll patients underwent history taking, physical examination, laboratory analysis, and ABPM. They were referred to the cardiology department for echocardiographic evaluation.ResultsIn total 85 patients with SNT, 112 patients with WCHT, 31 patients with MHT, and 81 patients with SHT were included. Going from SNT to SHT, body mass index (p < 0.0001), waist circumference (p < 0.0001), fasting blood glucose (p = 0.002), and uric acid (p = 0.029) rose progressively. Presence of metabolic syndrome was also highest in SHT and lowest in SNT (p < 0.0001).ConclusionMost of the metabolic risk factors were higher in patients with MHT and SHT when compared to SNT and WCHT. Studies are needed to determine whether metabolic risk factors play a causative role for the development of MHT and SHT.     

New algorithm for the diagnosis of hypertension

Most national and international guidelines for diagnosing hypertension include 24-h ambulatory blood pressure monitoring (ABPM) and self (home) BP monitoring (SBPM) as optional methods for identifying hypertensive patients. However, none of the current guidelines have yet included ABPM or SBPM as fundamental tools for diagnosing hypertension, preferring instead to rely on conventional office readings recorded by mercury sphygmomanometry. During the past 10 years, clinical outcome studies have consistently reported 24-h ABPM and SBPM to be significantly better predictors of cardiovascular events compared with the office BP, even when recorded under "research conditions." Based on the available evidence, the Canadian Hypertension Education Program has now developed an algorithm for diagnosing hypertension that offers three options: 1) conventional office BP, 2) SBPM, or 3) 24-h ABPM. Out-of-office BP measurements are recommended, whenever feasible, to minimize both measurement error associated with mercury sphygmomanometry and the white coat effect experienced by some patients.     

Prevalence of the white-coat effect at multiple visits before and during treatment

OBJECTIVE: To investigate the prevalence and persistence of the white-coat effect (WCE) and white-coat hypertension (WCH) on multiple blood pressure measurement occasions in hypertensive patients with and without treatment. DESIGN: Essential hypertensive patients in whom we took office blood pressure measurements (OBPM) at eight visits (three readings per visit) performed self blood pressure measurements (SBPM) for 1 week prior to each visit (42 readings per week) over a period of 1 year. All measurements were performed with the same automatic device (Omron 705CP). In addition, 24-h ambulatory blood pressure monitoring (ABPM) was performed at the start and at the end of the study. At the start, patients did not use any medication but on subsequent visits they were treated on the basis of their SBPM values. WCH was defined as an OBPM-value > or = 140 and/or 90 mmHg and a SBPM or daytime ABPM value < 135/85 mmHg. This definition was used irrespective of treatment. We also determined the prevalence of a substantial WCE (OBPM 20 mmHg systolic or 10 mmHg diastolic higher than SBPM or daytime ABPM). SETTING: Patients were recruited at hospital or general practice. PATIENTS: A total of 163 mild-to-moderate essential hypertensive patients with a mean age of 56 years (56% males). RESULTS: At eight blood pressure (BP) measurement occasions, 75% of all patients had a substantial WCE at least once, while 57% had WCH at least once. One-third of the patients consistently had a substantial WCE and 14% consistently had WCH on three or more occasions The magnitude of the WCE was significantly related to the height of blood pressure in treated but not in untreated patients. CONCLUSION: In some patients, WCH or a substantial WCE occurs consistently on multiple OBPM visits. Especially in untreated patients, the magnitude of the WCE varies widely among individuals. These results support the incorporation of SBPM and/or ABPM into optimal management of hypertension, not only to prevent misdiagnosis in untreated patients but also to determine the need for adjusting antihypertensive therapy in treated subjects.     

Consensus Conference on Self-blood pressure measurement. Clinical applications and diagnosis

The present study was aimed at reviewing the medical literature devoted to the clinical applications of self-blood pressure monitoring (SBPM) and at providing some recommendations regarding the use of SBPM for diagnostic purposes. The lack of reliability of conventional blood pressure (BP) measurement is largely related to the extreme variability of BP over time. SBPM provides a large number of readings and can be used to predict the results of repeated clinical measurements. The use of SBPM in the diagnosis of white coat hypertension can be proposed as a screening test: if it gives a positive result (a low home BP), it should be confirmed by ambulatory BP monitoring (ABPM). SBPM could improve patients' compliance with medication. Last, SBPM may be cost-effective for the management of hypertensive patients, by reducing costs of medication, number of clinic visits and costs of cardiovascular morbidity. Compared with ABPM, SBPM seems to have a less value for the initial diagnosis of hypertension and for predicting prognosis. In contrast, it should be of more value for the long term follow-up of patients with white coat hypertension and for the evaluation of treatment efficacy in patients with sustained hypertension. The use of SBPM in diabetic hypertensives, in pregnant women and in the elderly is encouraged, but needs further evaluation.     

Association of tumor necrosis factor-alpha with early target organ damage in newly diagnosed patients with essential hypertension

OBJECTIVES: To investigate the relationship between inflammatory parameters [high-sensitivity C-reactive protein (hs-CRP), serum tumor necrosis factor-alpha (TNF-alpha) and urinary TNF-alpha] with subclinical cardiac and renal markers of early target organ damage (TOD) in essential hypertension. METHODS: Preclinical TOD [left ventricular hypertrophy (LVH) and microalbuminuria (MAB)] was evaluated in 40 newly diagnosed never-treated patients with essential hypertension. Serum and urinary TNF-alpha and hs-CRP were measured as inflammatory parameters. Twenty-one BMI-matched and sex-matched normotensive, healthy individuals were included as control group. RESULTS: The serum levels of hs-CRP and the urinary TNF-alpha excretion were higher in hypertensive patients with MAB, whereas patients with LVH presented higher levels of urinary TNF-alpha. The only difference between hypertensive patients without TOD and healthy controls was the higher urinary excretion of TNF-alpha. Partial correlation analysis showed a significant association between urinary albumin excretion (UAE) and systolic blood pressure (r=0.62, P<0.0001), hs-CRP (r=0.64, P<0.001), urinary TNF-alpha (r=0.55, P=0.001) and Cornell product (r=0.33, P<0.05), whereas the Cornell product was related to UAE (r=0.34, P<0.05), urinary TNF-alpha (r=0.45, P<0.01), and hs-CRP (r=0.32, P<0.05). Multiple regression analysis demonstrated that the parameters independently correlated with UAE were mean blood pressure, Cornell product, hs-CRP and urinary TNF-alpha (adjusted R2=0.77, P<0.001), whereas UAE, urinary TNF-alpha and hs-CRP were independently correlated with Cornell product (adjusted R2=0.66, P<0.001). Multiple logistic regression analysis with TOD as the dependent variable showed that hs-CRP [2.24 (1.17-4.28), P<0.05] and urinary TNF-alpha [1.21 (1.02-1.44), P<0.05] were independently related to TOD. CONCLUSION: Urinary TNF-alpha is independently correlated with UAE and Cornell product in essential hypertension, suggesting that inflammation may participate in the development of TOD. In addition, urinary excretion of TNF-alpha might be an early marker of preclinical TOD in hypertensive patients. Finally, these results may be a basis to study the effect of the blockade of TNF-alpha activity on the development and progression of TOD in essential hypertension.     

Nocturnal pulse rate correlated with ambulatory blood pressure and target organ damage in patients with chronic kidney disease

The relationship between resting pulse rate (PR) and the occurrence of hypertension and cardiovascular (CV) mortality has been described in the general population. Few studies have examined the relationship between ambulatory PR, ambulatory blood pressure (BP), and target organ damage (TOD) in patients with chronic kidney disease (CKD). A total of 1509 patients with CKD were recruited in our hospital. Ambulatory blood pressure monitoring (ABPM) over a 24‐hours period was performed and referenced with clinical data in this cross‐sectional study. TOD was measured by estimated glomerular filtration rate (eGFR), left ventricular hypertrophy (LVH), and carotid intima‐media thickness (cIMT). Univariate and multivariate analyses were used to evaluate the relationship between PR, BP, and TOD. The percentage of male patients was 58.3% with a mean age of 44.6 ± 16.2 years. Nocturnal PR rather than 24‐hours PR or daytime PR was an independent risk factor for clinical hypertension, 24‐hours hypertension, BP dipper state, poor renal function, and LVH. In addition, the authors found that nighttime PR >74 beats/min (bpm) group was independently associated with clinical hypertension, 24‐hours hypertension, day and night hypertension, nondipping BP, lower eGFR, and LVH when compared with nighttime PR <64 bpm group. Furthermore, 1:1 propensity score matching between PR ≤74 bpm group and PR >74 bpm group was performed. Multivariate analyses indicated nighttime PR >74 bpm remained independently associated with clinical hypertension, daytime and nighttime hypertension, and LVH. An increased nocturnal PR is associated with TOD, higher BP, and nondipping BP in patients with CKD.     

Masked hypertension in obstructive sleep apnea syndrome

BACKGROUND: Ambulatory blood pressure (BP) monitoring (ABPM) detects subjects with normal clinic but high ambulatory 24-h BP, that is, masked hypertension. METHODS: One hundred and thirty newly diagnosed obstructive sleep apnea syndrome (OSAS) patients, free of recognized cardiovascular disease were included (111 men, age = 48 +/- 1 years, BMI = 27.6 +/- 0.4 kg/m, respiratory disturbance index (RDI = 42 +/- 2/h). Clinic BP, 24-h ABPM, baroreflex sensitivity (BRS), echocardiography and carotid intima-media thickness (IMT) were assessed. RESULTS: Forty-one patients (31.5%) were normotensive, 39 (30.0%) exhibited masked hypertension, four (3.1%) white-coat hypertension and 46 (35.4%) hypertension. Significant differences were found between normotensive, masked hypertensive and hypertensive patients in terms of BRS (10.5 +/- 0.8, 8.0 +/- 0.6 and 7.4 +/- 0.4 ms/mmHg, respectively, P < 0.001), carotid IMT (624 +/- 17, 650 +/- 20 and 705 +/- 23 microm, respectively, P = 0.04) and left ventricular mass index (37 +/- 1, 40 +/- 2 and 43 +/- 1 g/height2.7, respectively, P = 0.003). A clinic systolic BP more than 125 and a diastolic BP more than 83 mmHg led to a relative risk (RR) of 2.7 and a 90% positive predictive value for having masked hypertension. CONCLUSION: Masked hypertension is frequently underestimated in OSAS and is nearly always present when clinic BP is above 125/83 mmHg.     

Comparison of trough effect of telmisartan vs perindopril using self blood pressure measurement: EVERESTE study

This multicentre study was aimed at comparing the trough effect of telmisartan and perindopril on diastolic blood pressure (DBP), using self blood pressure measurement (SBPM). A second objective was to compare the data obtained from SBPM with those provided by automatic office BP measurement. A total of 441 mild-to-moderate hypertensive patients were randomised to receive either telmisartan 40 mg or perindopril 4 mg for a period of 12 weeks. Patients whose clinic DBP remained higher than or equal to 90 mmHg at the end of the 6th week (W6) were given a double-dose regimen. Office BP and SBPM were performed at baseline (W0), at W6 and at week 12 (W12), both with the same automatic device. A greater diminution of trough DBP was obtained with telmisartan (-6.6+/-6.7 mmHg) than with perindopril (-5.1+/-7.0 mmHg; P=0.018). Regarding clinic BP, the same results were observed. Doubling dose was significantly less frequent with telmisartan (41%; n=85) than with perindopril (55%; n=115, P=0.005). Mean values of SBPM were lower than office BP values, with a difference of a greater importance at W0 than at W12: 6.6 vs 4.7 mmHg for systolic blood pressure (P<0.005) and 3.2 vs 1.4 mmHg for DBP (P<0.0001). At W12, isolated office hypertension was found in 9% of the patients (n=37), while there were 14% of the patients (n=55) with isolated home hypertension. In conclusion, the trough effect on DBP was statistically higher with telmisartan than with perindopril. SBPM values were lower than office BP values, with greater differences before than after treatment. About a quarter of the patients were found to be controlled with a method but not with the other one.     

The frequency of combined target organ damage and the beneficial effect of ambulatory blood pressure monitoring in never treated mild-to-moderate hypertensive patients

The aim of this study was to determine the frequency of target organ damage (TOD) and the beneficial properties of ambulatory blood pressure monitoring (ABPM) for detecting patients who are at high risk for TOD and cardiovascular disease in never treated mild-to-moderate hypertension. Sixty-seven patients (28 males and 39 females, mean age, 49.6 +/- 9.5 years) were divided into two groups, dippers (group I, n = 43) and nondippers (group II, n = 24), according to nocturnal blood pressure (BP) reduction of less than 10%. The groups were compared with respect to demographic and laboratory data and the signs of TOD (microalbuminuria, left ventricular hypertrophy, and retinopathy). We also tested the relationship between ABPM and clinic BP findings with TOD. Group I had significantly lower values than group II for serum fibrinogen (0.28 +/- 0.06 versus 0.32 +/- 0.06 g/L, P = 0.02), uric acid (0.18 +/- 0.05 versus 0.25 +/- 0.11 mmo/L, P = 0.01), urinary sodium excretion (133.7 +/- 45.2 versus 161.8 +/- 52.2 mmol/L, P = 0.02), urinary albumin excretion (17.5 +/- 14.2 versus 31.3 +/- 19.7 mg/24-h, P = 0.001), left ventricular mass index (111.8 +/- 31.0 versus 128.7 +/- 36.6 g/m(2), P = 0.05), and the prevalence of hypertensive retinopathy (51% versus 83%, P = 0.01). The frequency of the combination of all three signs of TOD (microalbuminuria, left ventricular hypertrophy, and hypertensive retinopathy) was higher in nondippers than in dippers (71.4% versus 30%, P = 0.04). We suggest ABPM may provide clinical information to detect patients prone to develop cardiovascular risks and TOD in newly diagnosed mild-to-moderate hypertension.     

高血压病血压昼夜节律与左室肥厚关系的研究

目的 探讨血压负荷(BPL)与高血压靶器官损伤程度的关系,以及左室重量指数(LVMI)与动态血压(Ambulatory Blood Pressure,ABP)各参数之间的相关性。方法 采用无创性携带式动态血压监测仪对30例正常血压者,1级和2级高血压患者各25例进行了动态血压监测,同时用超声心动图检测左室重量指数。结果(1)正常组与1级高血压组之间血压负荷(SBP:4.83±2.95％vs59.75±22.12％;DBP:3.75±2.05％vs 61.75±18.24％)比较有显著性差异(P均<0.01);1级高血压组昼夜负荷差较大,呈杓型改变。2级高血压组的血压负荷(SBP:94.94±5.08％vs59.75±22.12％;DBP:91.75±10.08％vs61.75±18.24％)明显高于1级组(P均<0.01)。昼夜负荷呈非杓型改变。2级组左室肥厚(LVH)异常检出率76％明显高于1级组20％(P<0.01)。(2)高血压组LVMI与夜间SBP和DBP均显著正相关(P均<0.01),与夜间SBP和DBP下降率均显著负相关(P均<0.01)。结论 血压负荷对高血压靶器官损害程度的评价和预测有临床价值。夜间SBP与LVMI的相关性比DBP与LVMI的相关性更佳。     

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.     

Increased levels of transforming growth factor-beta1 in essential hypertension

BACKGROUND: Transforming growth factor-beta (TGF-beta) is a multifunctional cytokine that has been linked to vascular remodeling processes, myocardial hypertrophy, and renal fibrosis. Recently a correlation between serum levels of TGF-beta1 and blood pressure (BP) levels in patients with end-stage renal disease was shown. In addition, it is not clear whether TGF-beta1 is a causative factor in the pathogenesis of essential hypertension and associated with hypertensive target organ damage (TOD). METHODS: Using a TGF-beta1-specific sandwich ELISA, we compared plasma levels of active and total TGF-beta1 of 30 normotensive persons and 85 patients with essential hypertension with and without TOD, as measured by microalbuminuria or left ventricular hypertrophy. RESULTS: Active and total TGF-beta1 levels were significantly higher in plasma of patients with essential hypertension than in normotensive controls (P < .05 and P < .01, respectively). However, neither active nor total TGF-beta1 correlated with systolic or diastolic BP (R2 < 0.14 for all parameters). Levels of active and total TGF-beta1 were significantly higher in hypertensive patients with than without TOD (P < .05). CONCLUSIONS: Active and latent TGF-beta1 levels are markedly increased in plasma of hypertensive patients. We assume that TGF-beta1 contributes substantially to the development of TOD in essential hypertension, independent of BP levels.     

Obstructive sleep apnea and resistant hypertension: a case-control study

BACKGROUND: Obstructive sleep apnea syndrome (OSAS) has been linked to resistant hypertension, but the magnitude of this association and its independence of confounding have not been established. METHODS: Case patients were 63 patients with resistant hypertension (BP >or= 140/90 mm Hg using at least three BP-lowering drugs, including a diuretic), and control subjects were 63 patients with controlled BP receiving drug treatment. The primary outcome was the frequency of OSAS (apnea-hypopnea index [AHI] >or= 10 episodes per hour) determined with a portable home monitor. The comparison of AHI episodes in patients truly normotensive, truly hypertensive, and in patients with white coat or masked hypertension, based on BP determined at office and by ambulatory BP monitoring (ABPM) was a secondary outcome. RESULTS: Case patients and control subjects were well matched for confounding factors. OSAS was present in 45 case patients (71%) and in 24 control subjects (38%) [p < 0.001]. In a logistic regression model, OSAS was strongly and independently associated with resistant hypertension (odds ratio, 4.8; 95% confidence interval, 2.0 to 11.7). The AHI of case patients with normal BP in ABPM (white coat hypertension) and control subjects with abnormal BP in ABPM (masked hypertension) was intermediate between the AHI of individuals with normal and abnormal BP measures in both settings (p < 0.001). CONCLUSIONS: The magnitude and independence of the risk of OSAS for resistant hypertension strengthen the concept that OSAS is a risk factor for resistant hypertension. Comorbid OSAS should be considered in patients with resistant hypertension.