Xiaoxue Liu

Resting heart rate and risk of hypertension: results of the Kailuan cohort study.

Objective: Resting heart rate (RHR) is a predictive risk factor of the development of cardiovascular diseases, but its association with arterial hypertension has remained unclear. This study investigated the relationship between RHR and new-onset hypertension (NOH) in an Asian population. Methods: The Kailuan study is a prospective longitudinal cohort study on cardiovascular risk factors and cardiovascular or cerebrovascular events. Hazard ratios with 95% confidence intervals (CIs) were calculated using Cox regression modelling. Results: Out of 101 510 individuals originally included into the Kailuan study, 31 507 participants (mean age: 46.3 ± 11.5 years) were selected with no previous arterial hypertension or cardiac arrhythmias. After a mean follow-up period of 3.5 ± 0.9 years, 12 565 (39.88%) individuals developed arterial hypertension. Incidence of hypertension was 104.4, 109.7, 114.2 and 124.6 per 1000 person-years for each RHR quartile. In multivariate analysis with adjustment for blood pressure, blood lipids, diabetes mellitus and other parameters, hazard ratios for NOH increased significantly (P < 0.0001) with increasing RHR quartile. Increase in RHR by 10 beats/minute was associated with an 8% increase in NOH. Individuals in the highest RHR quartile as compared with participants in the lowest quartile demonstrated a 16% greater risk of developing NOH [hazard ratio 1.16; 95% confidence interval (CI) 1.11–1.23]. There were no significant interactions between RHR and prehypertension, diabetes mellitus, age and BMI in terms of NOH risk, respectively. Conclusion: Independently of other baseline parameters such as blood pressure, blood lipids and diabetes mellitus, elevated RHR significantly increases the risk of incident hypertension. Measuring RHR is helpful in predicting the risk of eventual arterial hypertension.

Resting Heart Rate and Risk of Cardiovascular Diseases and All-Cause Death: The Kailuan Study

Background Resting heart rate (RHR) predicts both cardiovascular and noncardiovascular death in different populations. However, the results of the association between RHR and cardiovascular diseases (CVDs) are inconsistent, especially for each subtype of CVDs. Objective The aim of this study was to prospectively explore the relationship between RHR and CVDs including myocardial infarction (MI), ischemic stroke, and hemorrhagic stroke and all-cause death in a general population. Methods The Kailuan study is a prospective longitudinal cohort study on cardiovascular risk factors and cardiovascular or cerebrovascular events. Hazard ratio (HR) with 95% confidence intervals (CI) were calculated using Cox regression modeling. Results We analyzed 92,562 participants (18–98 years old) in the Kailuan Study. CVDs were developed in 1,903 people during follow-ups. In multivariate analysis with adjustment for major traditional cardiovascular risk factors, HRs of the highest quintile group compared with the lowest quintile group of RHR for all-cause CVDs, MI, any stroke, ischemic stroke, hemorrhagic stroke, and all-cause death were 1.03 (95% CI, 0.98–1.07), 1.10 (95% CI, 1.01–1.20), 1.01 (95% CI, 0.97–1.06), 1.02 (95% CI, 0.96–1.07), 1.01 (95% CI, 0.92–1.11) and 1.18, (95% CI, 1.13–1.23), respectively. Conclusions The elevated RHR was independently associated with the increased risk for MI and all-cause death, but not for all-cause CVDs, any stroke, ischemic stroke, nor hemorrhagic stroke. This indicates that the elevated RHR might be a risk marker for MI and all-cause death in general populations.

Metabolic syndrome is associated with and predicted by resting heart rate: a cross-sectional and longitudinal study

Objective Although higher resting heart rate (RHR) has emerged as a predictor for lifespan, the underlying mechanisms remain obscure. The present study investigates whether a positive relationship exists between RHR and metabolic syndrome (MetS) and whether RHR predicts future MetS. Methods A cohort of 89 860 participants were surveyed during 2006–2007 in Kailuan/Tangshan, China. MetS was diagnosed when a participant presented at least three of the following: abdominal adiposity, low high density lipoprotein-cholesterol, high triglycerides, hypertension or impaired fasting glucose. RHR was derived from ECG recordings and subjects were stratified based on RHR. Some participants without MetS at baseline were followed-up for 4 years. Results At baseline, 23 150 participants (25.76%) had MetS. There was a positive association between RHR and MetS. The OR of having MetS was 1.49 (95% CI 1.32 to 1.69) in subjects with RHR at 95–104 compared with those at 55–64 beats per minute (bpm) (reference), after adjusting for variables including age, sex, education, cigarette smoking, alcohol drinking, physical activities, body mass index, hypertension, diabetes, hyperlipidaemia, inflammatory biomarkers and renal function. More importantly, when 43 725 individuals from the original study without MetS at baseline were followed-up, higher RHR was found to predict greater risk of MetS incidence. The OR of developing MetS 4 years later was 1.41 (95% CI 1.21 to 1.65) in subjects with RHR at 95–104 bpm compared with reference, after all adjustments. Conclusions Our cross-sectional and longitudinal findings provide evidence that RHR is an independent risk factor for existing MetS and a powerful predictor for future incidence of MetS.

Designing novel bulk metallic glass composites with a high aluminum content

The long-standing challenge for forming Al-based BMGs and their matrix composites with a critical size larger than 1 mm have not been answered over the past three decades. In this paper, we reported formation of a series of BMG matrix composites which contain a high Al content up to 55 at.%. These composites can be cast at extraordinarily low cooling rates, compatible with maximum rod diameters of over a centimetre in copper mold casting. Our results indicate that proper additions of transition element Fe which have a positive heat of mixing with the main constituents La and Ce can appreciably improve the formability of the BMG matrix composites by suppressing the precipitation of Al(La,Ce) phase resulted from occurrence of the phase separation. However, the optimum content of Fe addition is strongly dependant on the total amount of the Al content in the Al-(CoCu)-(La,Ce) alloys.

Hypertriglyceridemic waist phenotype and risk of cardiovascular diseases in China: Results from the Kailuan Study

BACKGROUND While some case-control studies have showed the correlation between the hypertriglyceridemic waist (HTGW) phenotype (increased WC and hypertriglyceridemia) and cardiovascular disease (CVD) events, there are few data regarding this correlation in cohort studies, especially in Asian populations that have a higher prevalence of central obesity than other populations. OBJECTIVE The aim of this study was to explore the relationship between HTGW phenotype and risk of incident CVD events among men and women in China. METHODS We analyzed 95,015 participants (18-98 years old) in the Kailuan Study. CVDs developed in 1958 people during follow-up. The cutoffs for defining HTGW phenotype were a waist circumference (WC) of 90 cm or more and a triglyceride level of 2.0 mmol/L or more for men and a WC of 85 cm or more and a triglyceride level of 1.5 mmol/L or more for women. Hazard ratios (HRs) with 95% confidence intervals (CIs) were calculated from Cox regression models. RESULTS Compared with participants who had a normal WC and a normal triglyceride level (NWNT), those with HTGW phenotype had a higher WC, body mass index, prevalence of hypertension and diabetes mellitus; and a lower level of high-density lipoprotein cholesterol. The HTGW group had an unadjusted HR of 1.76 (95% CI=1.55-1.99) for future CVDs compared with the NWNT group. After adjustment for confounders, the HR still remained significant (HR=1.24, 95% CI=1.07-1.44). CONCLUSIONS HTGW phenotype was associated with the risk of CVDs independently. HTGW phenotype might be a simple but useful tool to screen the individuals at a high risk for future CVDs, and it might be recommended in most clinical practices.

Cumulative Exposure to Ideal Cardiovascular Health and Incident Diabetes in a Chinese Population: The Kailuan Study

Background It is unclear whether ideal cardiovascular health (CVH), and particularly cumulative exposure to ideal CVH (cumCVH), is associated with incident diabetes. We aimed to fill this research gap. Methods and Results The Kailuan Study is a prospective cohort of 101 510 adults aged 18 to 98 years recruited in 2006–2007 and who were subsequently followed up at 2‐ (Exam 2), 4‐ (Exam 3), and 6 (Exam 4)‐year intervals after baseline. The main analysis is restricted to those individuals with complete follow‐up at all 4 examinations and who had no history of diabetes until Exam 3. Cumulative exposure to ideal CVH (cumCVH) was calculated as the summed CVH score for each examination multiplied by the time between the 2 examinations (score×year). Logistic regression models were used to assess the association between cumCVH and incident diabetes. In fully adjusted models, compared with the lowest quintile of cumCVH, individuals in the highest quintile had ~68% (95% confidence interval [CI] 60‐75) lower risk for incident diabetes (compared with 61% [95% CI 52‐69] lower risk when using baseline CVH). Every additional year lived with a 1‐unit increase in ideal CVH was associated with a 24% (95% CI 21‐28) reduction in incident diabetes. Conclusions Ideal CVH is associated with a reduced incidence of diabetes, but the association is likely to be underestimated if baseline measures of CVH exposure are used. Measures of cumulative exposure to ideal CVH are more likely to reflect lifetime risk of diabetes and possibly other health outcomes. Clinical Trial Registration URL: https://www.chictr.org. Unique identifier: ChiCTRTNC‐11001489.

Development of a novel high-entropy alloy with eminent efficiency of degrading azo dye solutions

In addition to its scientific importance, the degradation of azo dyes is of practical significance from the perspective of environmental protection. Although encouraging progress has been made on developing degradation approaches and materials, it is still challenging to fully resolve this long-standing problem. Herein, we report that high entropy alloys, which have been emerging as a new class of metallic materials in the last decade, have excellent performance in degradation of azo dyes. In particular, the newly developed AlCoCrTiZn high-entropy alloy synthesized by mechanical alloying exhibits a prominent efficiency in degradation of the azo dye (Direct Blue 6: DB6), as high as that of the best metallic glass reported so far. The newly developed AlCoCrTiZn HEA powder has low activation energy barrier, i.e., 30 kJ/mol, for the degrading reaction and thus make the occurrence of reaction easier as compared with other materials such as the glassy Fe-based powders. The excellent capability of our high-entropy alloys in degrading azo dye is attributed to their unique atomic structure with severe lattice distortion, chemical composition effect, residual stress and high specific surface area. Our findings have important implications in developing novel high-entropy alloys for functional applications as catalyst materials.

Association between high sensitivity C-Reactive protein and prevalence of asymptomatic carotid artery stenosis

INTRODUCTION Inflammation plays a key role in the pathophysiology of atherosclerosis. Little is known about the association between high sensitivity C-reactive protein (hs-CRP) especially long-term hs-CRP and asymptomatic carotid artery stenosis (ACAS) in healthy Chinese adults. The aim of this study was to assess the relationship between hs-CRP levels and the prevalence of ACAS in a Chinese community-based cohort. METHODS A sample of 5349 participants aged ≥ 40 years (40.36% women) were enrolled in this study, all without preexisting stroke. Ultrasonography of the bilateral carotid arteries was performed for the evaluation of carotid stenosis. Participants were stratified into three groups according to hs-CRP levels. We used both baseline (hs-CRP levels analyzed during 2010) and average hs-CRP values for the last four years (the average of hs-CRP levels analyzed at the year of 2006, 2008 and 2010) in the analysis. Multivariable logistic regression models were used to analyze the association between hs-CRP levels and ACAS. RESULTS A total of 356 (6.66%) subjects showed evidence of ACAS. Multivariate analysis showed that both baseline and average hs-CRP values for the last four years were independent indicators for the presence of ACAS (P for trend = 0.007, 0.001, respectively). Stratified by age and sex, higher baseline hs-CRP levels were associated with ACAS in old adults (≥ 60 y) (multivariate-adjusted, odds ratio [OR] = 1.03, 95% confidence interval [CI]: 1.01-1.05) and male (multivariate-adjusted, OR = 1.03, 95%CI: 1.01-1.05), but not in middle-aged adults (40-59 y) and female. Similarly, higher average hs-CRP values for the last four years were associated with ACAS in old adults and male, but not in middle-aged adults and female. CONCLUSION Both baseline and chronic elevation of serum hs-CRP were associated with ACAS, especially in older or male adults. hs-CRP might be used as a useful marker and a potential therapeutic target for carotid atherosclerosis.

Positive changes in ideal CVH metrics reduce the incidence of stroke.

The American Heart Association defined 7 ideal cardiovascular health (CVH) metrics and the benefits of them in reducing the incidence of stroke are well established, but it is unclear whether changes in them alter stroke risk. We calculated the changes of 7 ideal CVH metrics from 2006 to 2008 among 64,373 participants in the Kailuan study. We tested whether changes in the numbers and total scores for the CVH metrics were associated with the incidence of stroke in the 4.89 person-years follow-up. Cox regression modeling was used to estimate the risk of stroke. By year 2008, CVH metrics number of 32.54% participants improved (change ≥+1); 31.90% deteriorated (≤−1); 35.56% stayed the same; In the follow-up,we identified1,182 incident stroke events. Each increase in CVH metrics and every 1-point increase in total CVH score from 2006 to 2008 were associated with reduced odds of total stroke (hazard ratio = 0.87; 95% confidence interval; 0.83–0.92 and 0.89[0.86–0.92] respectively), after adjusting for age, gender, educational level, income and scores for the metrics of ideal CVH at baseline. Positive changes in ideal CVH metrics reduce the incidence of stroke. Our results support the concept that achieving ideal CVH helps to prevent stroke.

Sleep duration and risk of myocardial infarction and all-cause death in a Chinese population: the Kailuan study.

OBJECTIVE Although sleep is one of the most important health-related factors, the association of sleep duration with incidence of myocardial infarction or all-cause death has not been fully understood, especially in the general Chinese population. The objective of this study was to explore the relationship between sleep duration and risk of myocardial infarction and all-cause death in China. METHODS Out of the 101,510 participants who were originally included into the Kailuan prospective cohort study and followed up for an average of 3.98 years, 95,903 participants were actually sampled to evaluate the impacts of sleep duration on myocardial infarction and all-cause death. Sleep duration was categorized as ≤5, 6, 7, and 8 hours/night, and ≥9 hours per night. Cox proportional hazards models were used to analyze the association of sleep duration with the incidence of myocardial infarction and all-cause death. RESULTS After a mean follow-up period of 3.98 years, 423 participants developed myocardial infarction and 1793 participants died. A U-shape association between sleep duration and all-cause death was found. The age- and gender-adjusted hazard ratios (95% confidence interval [CI]) of all-cause death (with seven hours of daily sleep being considered for the reference group) for individuals reporting ≤5, 6, and 8 hours, and ≥9 hours were 1.29 (1.08-1.55), 0.97 (0.82-1.14), 1.11 (0.97-1.27), and 1.77 (1.31-2.38), respectively, with a p ≤ 0.01. However, no significant association was seen between sleep duration and myocardial infarction. CONCLUSION Both short and long duration of sleep might be potential predictors/markers for all-cause death, but not for myocardial infarction.