-Hua Li

Is isolated nocturnal hypertension a novel clinical entity? : Findings from a chinese population study

We reported previously that normotensive Chinese had higher nighttime diastolic blood pressure compared with non-Chinese. We, therefore, studied the prevalence and characteristics of isolated nocturnal hypertension (HT) and its association with arterial stiffness, an intermediate sign of target organ damage. We recorded ambulatory blood pressure, the central and peripheral systolic augmentation indexes, the ambulatory arterial stiffness index, and brachial-ankle pulse wave velocity in 677 Chinese enrolled in the JingNing population study (53.6% women; mean age: 47.6 years). Prevalence was 10.9% for isolated nocturnal HT (≥120/70 mm Hg from 10:00 pm to 4:00 am), 4.9% for isolated daytime HT (≥135/85 mm Hg from 8:00 am to 6:00 pm), and 38.4% for day-night HT. Patients with isolated nocturnal HT, compared with subjects with ambulatory normotension (45.8%), were older (53.7 versus 40.7 years), more often reported alcohol intake (68.9% versus 51.0%), had faster nighttime pulse rate (62.8 versus 60.7 bpm), had higher serum cholesterol (5.12 versus 4.77 mmol/L), and had higher blood glucose (4.84 versus 4.38 mmol/L). Similar to patients with isolated daytime HT or day-night HT, patients with isolated nocturnal HT had higher indexes of arterial stiffness (P<0.05) than subjects with ambulatory normotension (central augmentation index: 140% versus 134%; peripheral augmentation index: 82.6% versus 76.5%; ambulatory arterial stiffness index: 0.40 versus 0.35 U; brachial-ankle pulse wave velocity: 16.2 versus 14.7 m/s). Of 74 patients with isolated nocturnal HT, only 4 (5.4%) had hypertension on conventional office blood pressure measurement (≥140/90 mm Hg). In conclusion, isolated nocturnal HT can only be diagnosed by ambulatory blood pressure monitoring, is prevalent among Chinese, and is associated with increased arterial stiffness.

Brachial-Ankle Pulse Wave Velocity as a Predictor of Mortality in Elderly Chinese

Pulse wave velocity (PWV) is a measure of arterial stiffness and predicts cardiovascular events and mortality in the general population and various patient populations. In the present study, we investigated the predictive value of brachial-ankle PWV for mortality in an elderly Chinese population. Our study subjects were older (≥60 years) persons living in a suburban town of Shanghai. We measured brachial-ankle PWV using an automated cuff device at baseline and collected vital information till June 30, 2013, during follow-up. The 3876 participants (1713 [44.2%] men; mean [±SD] age, 68.1±7.3 years) included 2292 (59.1%) hypertensive patients. PWV was on average 17.8 (±4.0) m/s and was significantly (P<0.0001) associated with age (r=0.48) and in unadjusted analysis with all-cause (n=316), cardiovascular (n=148), stroke (n=46), and noncardiovascular mortality (n=168) during a median follow-up of 5.9 years. In further adjusted analysis, we studied the risk of mortality according to the decile distributions of PWV. Only the subjects in the top decile (23.3–39.3 m/s) had a significantly (P⩽0.003) higher risk of all-cause mortality (hazard ratio relative to the whole study population, 1.56; 95% confidence interval, 1.16–2.08), especially in hypertensive patients (hazard ratio, 1.86; 95% confidence interval, 1.31–2.64; P=0.02 for the interaction between PWV and hypertension). Similar trends were observed for cardiovascular, stroke, and noncardiovascular mortality, although statistical significance was not reached (P≥0.08). In conclusion, brachial-ankle PWV predicts mortality in elderly Chinese on the conditions of markedly increased PWV and hypertension.

Impact of Heart Rate on Central Hemodynamics and Stroke: A Meta-Analysis of β-Blocker Trials

BACKGROUND In a meta-analysis, we investigated effects of β-blockers on central hemodynamic measurements and explored the impact of heart rate (HR) on central hemodynamics and the risk of stroke. METHODS We searched randomized controlled trials that compared β-blockers with other classes of antihypertensive drugs in reducing central systolic blood pressure (cSBP) and augmentation index (cAI) and in preventing stroke. A random-effects model was used to compute pooled estimates. RESULTS In 9 trials (n = 754), β-blockers were less efficacious in reducing cAI than all the other classes of drugs (8.6%, P < 0.001). β-blockers were also less efficacious in reducing cSBP than angiotensin converting enzyme inhibitors (7.7 mm Hg, P = 0.02) and angiotensin receptor blockers (3.6 mm Hg, P = 0.005) but not the other classes of drugs (P ≥ 0.50). In a meta-regression analysis of these 9 trials, the baseline-adjusted difference in HR between randomized groups was associated with cAI (7.0% increase for each 10 bpm decrease in HR, P = 0.02), which was associated with cSBP (1.2 mm Hg increase for each 1% increase in cAI, P = 0.009). In 5 outcome trials, the pooled OR of stroke was 1.23 (P < 0.001), which would be accounted for by the difference in cSBP derived from the above meta-regression analysis. CONCLUSIONS Slowing HR with β-blockers may increase cAI and in turn may decrease cSBP less than with other classes of drugs. This mechanism might account for a smaller reduction in the risk of stroke when using β-blockers to treat hypertension.

Reference Values for the Arterial Pulse Wave in Chinese

BACKGROUND Pulse wave analysis using the SphygmoCor system allows the estimation of central pulse pressure (PP) and peripheral and central augmentation indexes (AIxs). We studied the limits of normality of these measurements in Chinese. METHODS We computed limits of normality as the 95% confidence boundaries from regression models relating the arterial indexes to age. RESULTS The reference population included 924 subjects (50.7% men, mean age 40.7 years) without overt cardiovascular disease. Men, compared to women, had higher peripheral (43.3 vs. 41.7 mm Hg; P = 0.01) and central (32.9 vs. 30.9 mm Hg; P < 0.0001) PPs, but lower peripheral (69.0 vs. 74.2%; P < 0.0001) and central (16.6 vs. 21.0%; P < 0.0001) AIxs. All arterial measurements showed a curvilinear relation with age. Both before and after adjustment for confounding factors, peripheral and central PPs increased less (P < or = 0.01) with age in men than in women, whereas the relation of peripheral and central AIxs with age was similar (P > or = 0.13) in both sexes. In 40-year-old Chinese, approximate thresholds for peripheral and central PPs, peripheral and central AIxs were 58 mm Hg, 48 mm Hg, 105% and 45%, respectively. Considering the age range from 20 to 60 years, thresholds varied within approximately 5 mm Hg, approximately 10 mm Hg, approximately 20%, and approximately 15% of the aforementioned thresholds for peripheral and central PPs, peripheral and central AIxs, respectively. CONCLUSIONS Pending further validation in prospective studies, our present study provides preliminary diagnostic thresholds for PP and AIxs in Chinese.

Isolated nocturnal hypertension and arterial stiffness in a Chinese population

ObjectiveWe reported previously that normotensive Chinese had higher nighttime diastolic blood pressure (BP) compared with non-Chinese. We, therefore, studied the prevalence and characteristics of isolated nocturnal hypertension and its association with arterial stiffness, an intermediate sign of target organ damage. MethodsWe recorded ambulatory BP, the central and peripheral systolic augmentation indexes, the ambulatory arterial stiffness index, and brachial-ankle pulse wave velocity in 677 Chinese enrolled in the JingNing population study (53.6% women; mean age: 47.6 years). ResultsThe prevalence of isolated nocturnal hypertension (≥120/70 mmHg from 22 : 00 to 4 : 00 h) was 10.9%. Patients with isolated nocturnal hypertension, compared with participants with ambulatory normotension (45.8%), were older (53.7 vs. 40.7 years), more often reported alcohol intake (68.9 vs. 51.0%), and had faster nighttime pulse rate (62.8 vs. 60.7 bpm), higher serum cholesterol (5.12 vs. 4.77 mmol/l), and higher blood glucose (4.84 vs. 4.38 mmol/l). They also had higher indexes of arterial stiffness (P<0.05) than participants with ambulatory normotension. Of 74 patients with isolated nocturnal hypertension, only four (5.4%) had hypertension on conventional office BP measurement (≥140/90 mmHg). ConclusionIsolated nocturnal hypertension can only be diagnosed by ambulatory BP monitoring, is prevalent among Chinese, and is associated with increased arterial stiffness.

The prevalence, incidence, management and risks of atrial fibrillation in an elderly Chinese population: a prospective study

BackgroundThere is limited information on prevalent and incident atrial fibrillation in Chinese. We aimed to investigate the prevalence, incidence, management and risks of atrial fibrillation in an elderly Chinese population.MethodsIn a population—based prospective study in elderly (≥60 years) Chinese, we performed cardiovascular health examinations including a 12-lead electrocardiogram at baseline in 3,922 participants and biennially during follow-up in 2,017 participants. We collected information on vital status during the whole follow-up period.ResultsThe baseline prevalence of atrial fibrillation was 2.0 % (n = 34) in 1718 men and 1.6 % (n = 36) in 2204 women. During a median 3.8 years of follow-up, the incidence rate of atrial fibrillation (n = 34) was 4.9 per 1000 person-years (95 % confidence interval [CI], 3.4–6.9). In univariate analysis, both the prevalence and incidence of atrial fibrillation were higher with age advancing (P < 0.0001) and in the presence of coronary heart disease (P ≤ 0.02). Of the 104 prevalent and incident cases of atrial fibrillation, only 1 (1.0 %) received anticoagulant therapy (warfarin). These patients with atrial fibrillation, compared with those with sinus rhythm, had significantly higher risks of all-cause (n = 261, hazard ratio [HR] 1.87, 95 % CI, 1.09–3.20, P = 0.02), cardiovascular (n = 136, HR 3.78, 95 % CI 2.17–6.58, P < 0.0001) and stroke mortality (n = 44, HR 6.31, 95 % CI 2.81–14.19, P = 0.0003).ConclusionsAtrial fibrillation was relatively frequent in elderly Chinese, poorly managed and associated with higher risks of mortality.

Anthropometric and metabolic phenotypes in relation to the ADRA2B deletion/insertion polymorphism in Chinese population.

Objective To investigate whether the ADRA2B D/I polymorphism is associated with anthropometric, metabolic, and blood pressure phenotypes in a Chinese population. Methods In 1306 participants enrolled in the JingNing population study, we measured anthropometry, blood pressure, plasma glucose, and serum lipids, and genotyped the ADRA2B D/I polymorphism. We defined overweight (BMI ≥ 25 kg/m2) and obesity (BMI ≥ 30 kg/m2) according to the WHO criteria. Results Genotype frequencies of the ADRA2B D/I polymorphism were significantly (P = 0.02) different between 228 (17.5%) overweight and obese participants and 1078 normal weight participants, but similar between 317 (24.3%) hypertensive participants and 989 normotensive participants. After adjustment for covariates, the ADRA2B DD compared with II homozygotes had significantly (P ≤ 0.01) lower BMI (21.9 versus 22.5 kg/m2), waist-to-hip ratio (0.835 versus 0.847), and triceps skinfold thickness (1.18 versus 1.27 cm) and had a significantly lower risk of overweight and obesity (odds ratio 0.52, 95% confidence interval, 0.49–0.54, P = 0.0001). Further analyses showed significant (P ≤ 0.01) interaction between the ADRA2B D/I polymorphism and physical activity in relation to BMI and waist-to-hip ratio. In physically less active participants [energy expenditure ≤3386 kcal/day (median)], DD compared with II homozygotes had lower BMI, waist-to-hip ratio and risk of overweight and obesity by 0.6 kg/m2, 0.012 and 60.6%, respectively. Conclusion The ADRA2B D allele is associated with a favourable anthropometric and metabolic profile in Chinese population, especially in physically less active participants.

Management of hypertension and diabetes mellitus by cardiovascular and endocrine physicians: a China registry

Objective: We investigated hypertension and diabetes mellitus in two management settings, namely cardiology and endocrinology, and their associations with albuminuria while accounting for the management of these two diseases. Methods: Our multicentre registry included patients (≥20 years) seen for hypertension in cardiology or for diabetes mellitus in endocrinology. We administered a questionnaire and measured blood pressure, glycosylated haemoglobin A1c and albuminuria. Results: Presence of both hypertension and diabetes was observed in 32.9% of hypertensive patients in cardiology (n = 1291) and 58.9% of diabetic patients in endocrinology (n = 1168). When both diseases were present, the use of combination antihypertensive therapy [odds ratio (OR) 0.31, P < 0.0001] and inhibitors of the renin–angiotensin system (OR 0.66, P = 0.0009) was less frequent in endocrinology than cardiology, and the use of combination antidiabetic therapy (OR 0.16, P < 0.0001) was less frequent in cardiology than endocrinology. The control of hypertension and diabetes, however, was not different between the two management settings (P ≥ 0.21), regardless of the therapeutic target (SBP/DBP < 140/90 or 130/80 mmHg and glycosylated haemoglobin A1c <7.0 or 6.5%). The prevalence of albuminuria was higher (P ⩽ 0.02) in the presence of both diseases (23.3%) than those with either hypertension (12.6%) or diabetes alone (15.9%). Conclusion: Hypertension and diabetes mellitus were often jointly present, especially in the setting of endocrinology. The management was insufficient on the use of combination antihypertensive therapy and inhibitors of the renin–angiotensin system in endocrinology and for combination antidiabetic therapy in cardiology, indicating a need for more intensive management and better control of both clinical conditions.

Validation of the Health & Life HL868BA blood pressure monitor for home blood pressure monitoring according to the European Society of Hypertension International Protocol.

ObjectiveThis study aimed to evaluate the accuracy of the automated Health & Life oscillometric upper arm blood pressure monitor HL868BA for home blood pressure monitoring according to the European Society of Hypertension International Protocol for blood pressure measuring devices in adults. MethodSystolic and diastolic blood pressures were sequentially measured in 33 adult Chinese using a mercury sphygmomanometer (two observers) and the HL868BA device (one supervisor). Ninety-nine pairs of comparisons were obtained from 15 participants in phase 1 and further 18 participants in phase 2 of the validation study. Data analysis was performed using the ESHIP Analyzer. ResultsThe HL868BA device successfully passed phase 1 of the validation study with a number of absolute differences between device and observers within 5, 10, and 15 mmHg for at least 31/45, 42/45, and 44/45 measurements (required 25, 35, and 40, respectively), respectively. The device also achieved the targets for phase 2.1, with 68/99, 91/99, and 95/99 differences within 5, 10, and 15 mmHg, respectively, for systolic blood pressure, and with 71/99, 88/99, and 94/99 within 5, 10, and 15 mmHg, respectively, for diastolic blood pressure. In phase 2.2, 22 and 28 participants had at least two of the three device–observers differences within 5 mmHg (required ≥22) for systolic and diastolic blood pressure, respectively. ConclusionThe Health & Life upper arm blood pressure monitor HL868BA can be recommended for home use in adults.

Independent effects of blood pressure and parathyroid hormone on aortic pulse wave velocity in untreated Chinese patients

Objective: Whether or not calcium-regulating hormones stiffen arteries independent of blood pressure (BP) is uncertain. We investigated the independent associations of carotid–femoral pulse wave velocity (PWV) with 25-hydroxy-vitamin D [25(OH)D], parathyroid hormone (PTH) and 24-h ambulatory BP in untreated Chinese patients. Methods: Consecutive untreated patients referred for ambulatory BP monitoring were recruited. PWV was measured with a high-fidelity micromanometer and the SphygmoCor software (AtCor Medical, West Ryde, New South Wales, Australia). Serum 25(OH)D and PTH were determined by electrochemiluminescence immunoassay. Analysis of variance, single and multiple regressions were applied for analyses. Results: In 1052 untreated patients (50.7% women; mean age, 51 years), PWV averaged 7.8 m/s, 24-h SBP/DBP 126.5/81.7 mmHg, serum 25(OH)D and PTH 36.0 nmol/l and 61.6 pg/ml, respectively. In multivariable-adjusted analyses, BP (P < 0.001) and PTH (P = 0.012) increased from less than 25th to at least 75th percentile of the PWV distribution. In continuous analyses, PWV independently increased by 0.40/0.23 m/s per 1-SD increment in SBP/DBP (P < 0.001) and by 0.14 m/s for a doubling of serum PTH (P = 0.029). Associations of PWV with BP were tighter than with PTH (P < 0.001). In pathway analysis, the effect of PTH on PWV did not run via serum or urinary calcium (P = 0.65), but PTH had both a direct (P = 0.026) and a BP-mediated indirect effect (P = 0.043) on PWV. In none of our analyses were PWV associated with serum 25(OH)D. Conclusion: Arterial stiffness, as assessed by PWV, independently increased both with BP and with PTH, but BP remains the main driver of arterial stiffening.