Ethnic differences in arterial stiffness the Helius study

Central and local arterial stiffness in White Europeans compared to age-, sex-, and BMI-matched South Asians

BACKGROUND

Ethnicity impacts cardiovascular disease (CVD) risk, and South Asians demonstrate a higher risk than White Europeans. Arterial stiffness is known to contribute to CVD, and differences in arterial stiffness between ethnicities could explain the disparity in CVD risk. We compared central and local arterial stiffness between White Europeans and South Asians and investigated which factors are associated with arterial stiffness.

METHODS

Data were collected from cohorts of White Europeans (the Netherlands) and South Asians (India). We matched cohorts on individual level using age, sex, and body mass index (BMI). Arterial stiffness was measured with ARTSENS® Plus. Central stiffness was expressed as carotid-femoral pulse wave velocity (cf-PWV, m/s), and local carotid stiffness was quantified using the carotid stiffness index (Beta) and pressure-strain elastic modulus (Epsilon, kPa). We compared arterial stiffness between cohorts and used multivariable linear regression to identify factors related to stiffness.

RESULTS

We included n = 121 participants per cohort (age 53±10 years, 55% male, BMI 24 kg/m2). Cf-PWV was lower in White Europeans compared to South Asians (6.8±1.9 vs. 8.2±1.8 m/s, p<0.001), but no differences were found for local stiffness parameters Beta (5.4±2.4 vs. 5.8±2.3, p = 0.17) and Epsilon (72±35 vs. 70±31 kPa, p = 0.56). Age (standardized β, 95% confidence interval: 0.28, 0.17-0.39), systolic blood pressure (0.32, 0.21-0.43), and South Asian ethnicity (0.46, 0.35-0.57) were associated with cf-PWV; associations were similar between cohorts (p>0.05 for interaction). Systolic blood pressure was associated with carotid stiffness in both cohorts, whereas age was associated to carotid stiffness only in South Asians and BMI only in White Europeans.

CONCLUSION

Ethnicity is associated with central but not local arterial stiffness. Conversely, ethnicity seems to modify associations between CVD risk factors and local but not central arterial stiffness. This suggests that ethnicity interacts with arterial stiffness measures and the association of these measures with CVD risk factors.

Association between the reflection magnitude and blood pressure in a multiethnic cohort: the Healthy Life in an Urban Setting study

AIMS

Reflection magnitude (RM), the ratio of the amplitudes of the backward and forward central arterial pressure waves, has been shown to predict cardiovascular events. However, the association with blood pressure (BP) and hypertension is unclear.

METHODS

We assessed RM in 10 195 individuals of Dutch, South-Asian Surinamese, African Surinamese, Ghanaian, Turkish and Moroccan origin aged between 18 and 70 years (54.2% female) participating in the Healthy Life in an Urban Setting study. To determine RM, central arterial pressure and flow were reconstructed from finger BP. Hypertension was defined based on office-BP and medication. Associations with BP, hypertension, and hypertensive organ damage were assessed using linear regression models with correction for relevant covariates.

RESULTS

Mean RM was 62.5% (standard deviation [SD] 8.0) in men and 63.8% (SD 8.1) in women. RM was lowest in Dutch and highest in South-Asian and African participants. RM increased linearly with 1.35 (95% confidence interval [CI] 1.23-1.46) for every 10 mmHg increase in systolic BP from 120 mmHg onwards, while the relation with diastolic BP was nonlinear. RM was 2.40 (95% CI 2.04-2.76) higher in hypertensive men and 3.82 (95% CI 3.46-4.19) higher in hypertensive women compared to normotensive men and women. In hypertensive men and women with ECG-based left ventricular hypertrophy or albuminuria RM was 1.64 (95% CI 1.09-2.20) and 0.94 (95% CI 0.37-1.52) higher compared to hypertensive participants without hypertensive organ damage.

CONCLUSION

RM is associated with BP, hypertension and hypertensive organ damage, and may in part explain disparities in hypertension associated cardiovascular risk.

Association between the reflection magnitude and blood pressure in a multiethnic cohort: the Healthy Life in an Urban Setting study

Aims:

Reflection magnitude (RM), the ratio of the amplitudes of the backward and forward central arterial pressure waves, has been shown to predict cardiovascular events. However, the association with blood pressure (BP) and hypertension is unclear.

Methods:

We assessed RM in 10 195 individuals of Dutch, South-Asian Surinamese, African Surinamese, Ghanaian, Turkish and Moroccan origin aged between 18 and 70 years (54.2% female) participating in the Healthy Life in an Urban Setting study. To determine RM, central arterial pressure and flow were reconstructed from finger BP. Hypertension was defined based on office-BP and medication. Associations with BP, hypertension, and hypertensive organ damage were assessed using linear regression models with correction for relevant covariates.

Results:

Mean RM was 62.5% (standard deviation [SD] 8.0) in men and 63.8% (SD 8.1) in women. RM was lowest in Dutch and highest in South-Asian and African participants. RM increased linearly with 1.35 (95% confidence interval [CI] 1.23–1.46) for every 10 mmHg increase in systolic BP from 120 mmHg onwards, while the relation with diastolic BP was nonlinear. RM was 2.40 (95% CI 2.04–2.76) higher in hypertensive men and 3.82 (95% CI 3.46–4.19) higher in hypertensive women compared to normotensive men and women. In hypertensive men and women with ECG-based left ventricular hypertrophy or albuminuria RM was 1.64 (95% CI 1.09–2.20) and 0.94 (95% CI 0.37–1.52) higher compared to hypertensive participants without hypertensive organ damage.

Conclusion:

RM is associated with BP, hypertension and hypertensive organ damage, and may in part explain disparities in hypertension associated cardiovascular risk.

Are you as old as your arteries? Comparing arterial aging in Japanese and European patient groups using cardio-ankle vascular index

BACKGROUND

Most comparisons of arterial stiffness between ethnic groups focus on pulse wave velocity. This study used the cardio-ankle vascular index (CAVI) in European compared to Japanese individuals to investigate how cardiovascular risk factors affect arterial aging across geographic regions.

METHODS

Four hundred and ninety-four European and 1044 Japanese individuals underwent measurements of CAVI, blood pressure and information on cardiovascular risk factors. Both datasets included individuals with 0-5 cardiovascular risk factors.

RESULTS

Average CAVI was higher in the Japanese than the European group in every age category, with significant differences up to 75 years for males and 85 for females. The correlation of CAVI with age, controlled for cardiovascular risk factors, was slightly higher in Japanese females (r = 0.594 vs. Europeans r = 0.542) but much higher in European males (r = 0.710 vs. Japanese r = 0.511). There was a significant correlation between CAVI and total cardiovascular risk factors in the Japanese (r = 0.141, P < 0.001) but not the European group. On linear regression, average CAVI was significantly dependent on age, sex, diabetes, BMI, SBP and geographic region. When divided into 'healthy' vs. 'high risk', the healthy group had a steeper correlation with age for Europeans (r = 0.644 vs. Japanese r = 0.472, Fisher's Z P < 0.001), whereas in the high-risk group, both geographic regions had similar correlations.

CONCLUSION

Japanese patient groups had higher arterial stiffness than Europeans, as measured by CAVI, controlling for cardiovascular risk factors. Europeans had greater increases in arterial stiffness with age in healthy individuals, particularly for males. However, cardiovascular risk factors had a greater impact on the Japanese group.

Blood Pressure and Stroke: A Review of Sex- and Ethnic/Racial-Specific Attributes to the Epidemiology, Pathophysiology, and Management of Raised Blood Pressure

Raised blood pressure (BP) is the leading cause of death and disability worldwide, and its particular strong association with stroke is well established. Although systolic BP increases with age in both sexes, raised BP is more prevalent in males in early adulthood, overtaken by females at middle age, consistently across all ethnicities/races. However, there are clear regional differences on when females overtake males. Higher BP among males is observed until the seventh decade of life in high-income countries, compared with almost 3 decades earlier in low- and middle-income countries. Females and males tend to have different cardiovascular disease risk profiles, and many lifestyles also influence BP and cardiovascular disease in a sex-specific manner. Although no hypertension guidelines distinguish between sexes in BP thresholds to define or treat hypertension, observational evidence suggests that in terms of stroke risk, females would benefit from lower BP thresholds to the magnitude of 10 to 20 mm Hg. More randomized evidence is needed to determine if females have greater cardiovascular benefits from lowering BP and whether optimal BP is lower in females. Since 1990, the number of people with hypertension worldwide has doubled, with most of the increase occurring in low- and-middle-income countries where the greatest population growth was also seen. Sub-Saharan Africa, Oceania, and South Asia have the lowest detection, treatment, and control rates. High BP has a more significant effect on the burden of stroke among Black and Asian individuals than Whites, possibly attributable to differences in lifestyle, socioeconomic status, and health system resources. Although pharmacological therapy is recommended differently in local guidelines, recommendations on lifestyle modification are often very similar (salt restriction, increased potassium intake, reducing weight and alcohol, smoking cessation). This overall enhanced understanding of the sex- and ethnic/racial-specific attributes to BP motivates further scientific discovery to develop more effective prevention and treatment strategies to prevent stroke in high-risk populations.

KCNJ5 Somatic Mutations in Aldosterone-Producing Adenoma Are Associated with a Greater Recovery of Arterial Stiffness

Simple Summary

Primary aldosteronism (PA) is the most common form of secondary hypertension and induces various cardiovascular injuries. Aldosterone-producing adenoma (APA) is one of the major forms of PA. The occurrence of APA is closely correlated with somatic mutations, including KCNJ5. We described here the impact of KCNJ5 somatic mutations on arterial stiffness excluding the influence of age, sex, and blood pressure status. We found KCNJ5 mutation carriers had similar arterial stiffness before surgery, but greater improvement of arterial stiffness after adrenalectomy compared with non-carriers. Hence, APA patients with KCNJ5 mutations had a greater improvement in arterial stiffness after adrenalectomy than those without mutations.

Abstract

Primary aldosteronism is the most common form of secondary hypertension and induces various cardiovascular injuries. In aldosterone-producing adenoma (APA), the impact of KCNJ5 somatic mutations on arterial stiffness excluding the influence of confounding factors is uncertain. We enrolled 213 APA patients who were scheduled to undergo adrenalectomy. KCNJ5 gene sequencing of APA was performed. After propensity score matching (PSM) for age, sex, body mass index, blood pressure, number of hypertensive medications, and hypertension duration, there were 66 patients in each group with and without KCNJ5 mutations. The mutation carriers had a higher aldosterone level and lower log transformed brachial–ankle pulse wave velocity (baPWV) than the non-carriers before PSM, but no difference in log baPWV after PSM. One year after adrenalectomy, the mutation carriers had greater decreases in log plasma aldosterone concentration, log aldosterone–renin activity ratio, and log baPWV than the non-carriers after PSM. Only the mutation carriers had a significant decrease in log baPWV after surgery both before and after PSM. KCNJ5 mutations were not correlated with baseline baPWV after PSM but were significantly correlated with ∆baPWV after surgery both before and after PSM. Conclusively, APA patients with KCNJ5 mutations had a greater regression in arterial stiffness after adrenalectomy than those without mutations.

Estimated Arterial Stiffness and Prediction of Vascular Aging: The Rising of a New Era

Arterial stiffness has been associated with cardiovascular events and correlated with cardiovascular risk factors. In the new guidelines of the European Society of Hypertension, the evaluation of arterial stiffness, and specifically carotid-femoral pulse wave velocity (c-f PWV), was taken into account for the detailed screening of the hypertensive population. Despite the importance of arterial stiffness as a target organ damage, the measurement is time-consuming, not practical, needs expensive equipment and experienced staff. For all these reasons, c-f PWV is not recommended for the everyday clinical practice and its current use is restricted for research purposes. The importance of arterial properties in clinical practice and cardiovascular prevention is well known. Hence, the estimation of arterial stiffness and vascular health based on parameters that affect arterial stiffness, but without the use of a machine, is a new promising field. Furthermore, the relationship between age-related MRI abnormalities as well as ultrafast ultrasound with vascular effect gives a new promise for future vascular aging assessment.

Inflammation and its associations with aortic stiffness, coronary artery disease and peripheral artery disease in different ethnic groups: The HELIUS Study

BACKGROUND

evidence shows important ethnic differences in vascular dysfunction rates; however, the mechanisms driving these differences remain unclear. One potential factor is the ethnic differences in the role of inflammation in vascular injury. We tested the hypothesis that low-grade inflammation is unequally associated with vascular dysfunction in different ethnic groups.

METHODS

we included 5698 participants (similar-sized Dutch, African Surinamese, South-Asian Surinamese, Ghanaians, Turkish, and Moroccans) of the HELIUS study (the Netherlands) conducted between 2011 and 2015. Logistic regression was used to examine the associations of Z-score inflammatory biomarker concentration (high sensitivity C-reactive protein [hs-CRP], fibrinogen, and d-dimer) with vascular dysfunction (aortic stiffness, coronary artery disease [CAD], and peripheral artery disease [PAD]), with adjustments for age, sex, smoking (pack-years), BMI, hypertension, HbA1c, total cholesterol, and statin use.

FINDINGS

in the fully adjusted models, higher Z-score hs-CRP was positively associated with CAD in Dutch [OR 1·63, (95% CI 1·21-2·18)] and PAD in South Asians [1·25(1·03-1·53)], respectively. Higher Z-score fibrinogen was positively associated with CAD in African Surinamese [1·28(1·03-1·59)] while higher Z-score d-dimer was positively associated with PAD in Moroccans [1·39(1·01-1·93)]. Higher Z-score hs-CRP [0·71(0·54-0·94)] and fibrinogen [0·75(0·58-0·97)] concentrations were negatively associated with PAD in African Surinamese.

INTERPRETATION

our study shows that inflammatory biomarkers are unequally associated with vascular dysfunction in different ethnic groups. These observations provide opportunities for future studies aimed at assessing the predictive roles of inflammation on vascular disease in different ethnic groups.

Decreased heritability and emergence of novel genetic effects on pulse wave velocity from youth to young adulthood

Increased arterial stiffness measured by pulse wave velocity (PWV) is an important parameter in the assessment of cardiovascular risk. Our previous longitudinal study has demonstrated that carotid-distal PWV showed reasonable stability throughout youth and young adulthood. This stability might be driven by genetic factors that are expressed consistently over time. We aimed to illustrate the relative contributions of genetic and environmental factors to the stability of carotid-distal PWV from youth to young adulthood. We also examined potential ethnic differences. For this purpose, carotid-distal PWV was measured twice in 497 European American (EA) and African American (AA) twins, with an average interval time of 3 years. Twin modelling on PWV showed that heritability decreased over time (62–35%), with the nonshared environmental influences becoming larger. There was no correlation between the nonshared environmental factors on PWV measured at visit 1 and visit 2, with the phenotypic tracking correlation (r = 0.32) completely explained by shared genetic factors over time. Novel genetic influences were identified accounting for a significant part of the variance (19%) at the second measurement occasion. There was no evidence for ethnic differences. In summary, novel genetic effects appear during development into young adulthood and account for a considerable part of the variation in PWV. Environmental influences become larger with age for PWV.

Associations between macrovascular and renal microvascular dysfunction in type 2 diabetes and non-diabetes: the HELIUS study

BACKGROUND

Although the associations between measures of macrovascular and microvascular dysfunctions are well characterized in diabetes, there is limited data on these associations in individuals without diabetes. We compared the associations between macrovascular dysfunction and renal microvascular dysfunction in individuals with type 2 diabetes (T2D) and without diabetes.

METHODS

Cross-sectional analyses of baseline data from the multiethnic Healthy Life in an Urban Setting (HELIUS) study (Amsterdam, the Netherlands), including 986 participants with T2D and 7680 participants without diabetes were done. Logistic regression analyses were used to examine the associations between macrovascular dysfunction [aortic stiffness, coronary artery disease (CAD), peripheral artery disease (PAD), and stroke] and renal microvascular dysfunction [albuminuria] with adjustments for age, sex, ethnicity, waist-to-hip ratio, systolic blood pressure, LDL-cholesterol, and smoking (and HbA1c and diabetes duration for the T2D group).

RESULTS

In the fully adjusted models, aortic stiffness was associated with albuminuria in individuals with T2D [OR 2.55; 95% CI,1.30-4.98], but not without diabetes [0.96; 0.63-1.45]; stroke was associated with albuminuria in T2D [2.40;1.10-5.25], but not in non-diabetes [1.39;0.83-2.33]. In age-sex adjusted models, CAD was associated with albuminuria in T2D [1.65;1.09-2.50] and in non-diabetes [1.56;1.13-2.15]; the associations were no longer significant in the fully adjusted model. There were no associations between PAD and albuminuria in T2D and non-diabetes.

CONCLUSIONS

Our study shows important differences in the associations between measures of macrovascular and renal microvascular dysfunction in T2D and non-diabetes. These findings provide opportunities for future research aimed at prevention and treatment strategies for individuals with vascular dysfunction.

Ethnic differences in subclinical vascular function in South Asians, Whites, and African Americans in the United States

BACKGROUND

South Asians are a high-risk ethnic group for cardiovascular disease despite having lower levels of conventional cardiovascular risk factors such as obesity and smoking. Ethnic differences in pulse wave reflections, arterial stiffness, and subclinical atherosclerosis as measured using augmentation index (AIX), pulse wave velocity (PWV), and carotid intima-media thickness (CIMT) may reflect some of this excess risk.

METHODS

We conducted a cross-sectional analysis of pooled data from three community-based sources in Atlanta, Georgia, USA. Data on 530 South Asians collected from local health fairs was compared with data on 507 White and 192 African Americans from the Emory Predictive Health Initiative and 351 White and 382 African Americans from the Morehouse and Emory Team up to Eliminate Health Disparities Study.

RESULTS

Linear regression models adjusted for age, sex, smoking, MAP, fasting glucose, TC, HDL-C, creatinine, and body mass index were used to assess the relationship between ethnicity and vascular function measures. In fully adjusted models, South Asians had higher heart rate corrected AIX as compared with Whites and African Americans (by 5.47%, p < 0.01 and 3.50%, p < 0.01; respectively), but lower PWV (by 0.51 m/s, p < 0.01 and 0.72 m/s, p < 0.01; respectively) and lower CIMT (by 0.02 mm p = 0.03 and 0.04 mm p < 0.01; respectively).

CONCLUSIONS

Systemic pulse wave reflections, independent of other risk factors, are higher in South Asians as compared with Whites and African Americans. Future research is needed to determine whether higher AIX explains the increased cardiovascular risk among South Asians.

Ethnicity and Arterial Stiffness

Early vascular aging reflects increased arterial stiffness of central blood vessels at young chronological ages and powerfully predicts cardiovascular events and mortality, independent of routine brachial blood pressure and other risk factors. Since ethnic disparities exist in routine blood pressure, in hypertension and cardiovascular outcomes, this review evaluates major studies comparing arterial stiffness through the life course between different ethnic groups or races (which have no biological definition)-in children, adolescents, young, and middle-aged adults and the very elderly. Most report that compared with white European-origin samples, populations of black African descent have increased central arterial stiffness throughout different life stages, as well as a more rapid increase in arterial stiffness at young ages. Exceptions may include African Caribbean origin people in Europe. Differences in vascular structure and function are clearest, where obesity, socioeconomic, and psychosocial factors are most marked. Few studies evaluate a wider spectrum of ethnic groups or factors contributing to these ethnic disparities. Genetic effects are not obvious; maternal risk and intergenerational studies are scarce. Nevertheless, across all ethnic groups, for given levels of blood pressure and age, some people have stiffer central arteries than others. These individuals are most at risk of vascular events and mortality and, therefore, may benefit from early, as yet untested, preventive action and treatment.

Increased Arterial Stiffness in Adolescents With Obesity

Increased arterial stiffness (AS) is an early sign of cardiovascular disease. Influence of weight, puberty, and insulin resistance (IR) on AS in adolescents is unclear. Therefore, this study compared AS, assessed with pulse wave velocity (PWV) and augmentation index (AIx), of adolescents with and without obesity and evaluated the influence of puberty and IR on AS. Sixty-two lean and 61 adolescents with obesity were included. Significantly higher PWV was observed in adolescents with obesity (4.1 ms⁻¹ [2.4 to 5.6 ms⁻¹] vs 3.6 ms⁻¹ [0.4 to 6.1 ms⁻¹]; P = .01), while AIx was not significant different. However, significantly higher AIx was observed in adolescents with obesity and IR (3.0 [−17.5% to 28.5%] vs −3.0 [−19.0% to 13.0%]; P = .01). For Tanner stages, no differences were observed. The higher PWV in adolescents with obesity and higher AIx in adolescents with obesity and IR both indicate an increased AS. Consequently, measurement of AS should be considered in adolescents with obesity and IR as part of cardiovascular risk assessment.

Determinants of pulse wave velocity trajectories from youth to young adulthood: the Georgia Stress and Heart Study

OBJECTIVE

Increased arterial stiffness measured by pulse wave velocity (PWV) has been shown to be an important parameter of cardiovascular risk. Longitudinal development of PWV from youth to early adulthood and its possible sociodemographic, anthropometric, hemodynamic and behavioral moderators will be illustrated.

METHODS

Individual growth curves of carotid-distal PWV across age were created for 559 African American and European American men and women with a maximum of five assessments over an average of 7-year follow-up (mean age at participants' first assessment, 22.3 ± 3.4).

RESULTS

African Americans and men had significantly higher PWV than did European Americans and women (Ps < 0.01), respectively. A three-way interaction (P < 0.001) between age, sex and ethnicity was observed with African American men displaying a larger rate of increase in PWV with age than the other three ethnic and sex groups. The ethnicity and sex effects on PWV persisted when controlling for other moderators. Waist circumference was the strongest anthropometric predictor but its effect on PWV was only significant in women. Mean arterial pressure was the strongest hemodynamic predictor, marital status of parents was the strongest socioeconomic predictor and marijuana use was the strongest behavioral predictor of PWV. The best-fitting full model explained in total 59.4% of the between-subject variance in PWV with ethnicity, sex and age explaining 25.6%.

CONCLUSION

We observed significant ethnic and sex differences in longitudinal trajectories of PWV in youth and young adults. In addition, individual differences in PWV growth can largely be explained by mean arterial pressure, waist, marital status of parents and marijuana use.

Prognostic significance of arterial stiffness and osteoprotegerin in patients with stable coronary artery disease

BACKGROUND

Arterial stiffness and vascular calcification significantly contribute to coronary atherosclerosis progression. The prognostic value of increased arterial stiffness and vascular calcification in subjects with stable coronary artery disease (CAD) after percutaneous coronary intervention(PCI) is currently under question.

MATERIALS AND METHODS

We randomly enrolled 262 patients with stable CAD 1 month after successful PCI. Carotid-femoral pulse wave velocity (PWV) was measured as a well-established index of central aortic stiffness. Osteoprotegerin (OPG) plasma levels were measured as a biomarker of vascular calcification. Patients were followed up prospectively up to 52 months. The primary endpoint was the composite of death from cardiovascular causes, myocardial infarction, stroke or hospitalization for cardiovascular causes.

RESULTS

During the follow-up period, 48 patients presented the primary composite endpoint. Subjects who presented the primary endpoint, compared to subjects free of cardiovascular events, had significantly increased PWV (9.45 ± 2.19 m/s vs 8.73 ± 2.07 m/s, P = .04) and OPG levels (4.21 ± 2.19 pmol/L vs 3.18 ± 1.74 pmol/L, P = .003). Survival analysis indicated that PWV predicted adverse cardiac events MACE (Hazard ratio = 1.29 95%CI: 1.07-1.57, P = .008) independently from confounders such as age, sex, smoking habits, ejection fraction, extent of coronary artery disease, hypertension and diabetes mellitus. Interestingly, for every increase in pulse wave velocity by 1 m/s, there is an anticipated increase in the risk of major adverse cardiovascular event (MACE) by 29%.

CONCLUSIONS

These findings extend the current knowledge concerning the role of arterial stiffness as powerful biomarkers in cardiovascular disease. Measurement of PWV might have a role in ascertaining prognosis and managing treatment in patients with stable CAD after PCI.

Cohort profile: the Healthy Life in an Urban Setting (HELIUS) study in Amsterdam, The Netherlands

PURPOSE

Ethnic minority groups usually have a more unfavourable disease risk profile than the host population. In Europe, ethnic inequalities in health have been observed in relatively small studies, with limited possibilities to explore underlying causes. The aim of the Healthy Life in an Urban Setting (HELIUS) study is to investigate the causes of (the unequal burden of) diseases across ethnic groups, focusing on three disease categories: cardiovascular diseases, mental health and infectious diseases.

PARTICIPANTS

The HELIUS study is a prospective cohort study among six large ethnic groups living in Amsterdam, the Netherlands. Between 2011 and 2015, a total 24 789 participants (aged 18-70 years) were included at baseline. Similar-sized samples of individuals of Dutch, African Surinamese, South-Asian Surinamese, Ghanaian, Turkish and Moroccan origin were included. Participants filled in an extensive questionnaire and underwent a physical examination that included the collection of biological samples (biobank).

FINDINGS TO DATE

Data on physical, behavioural, psychosocial and biological risk factors, and also ethnicity-specific characteristics (eg, culture, migration history, ethnic identity, socioeconomic factors and discrimination) were collected, as were measures of health outcomes (cardiovascular, mental health and infections). The first results have confirmed large inequalities in health between ethnic groups, such as diabetes and depressive symptoms, and also early markers of disease such as arterial wave reflection and chronic kidney disease, which can only just partially be explained by inequalities in traditional risk factors, such as obesity and socioeconomic status. In addition, the first results provided important clues for targeting prevention and healthcare.

FUTURE PLANS

HELIUS will be used for further research on the underlying causes of ethnic differences in health. Follow-up data will be obtained by repeated measurements and by linkages with existing registries (eg, hospital data, pharmacy data and insurance data).

Association Between Elevated Pulse Pressure and High Resting Coronary Blood Flow Velocity in Patients With Angiographically Normal Epicardial Coronary Arteries

BACKGROUND

The aim of our study was to evaluate the relationship of pulse pressure (PP), a raw index of arterial stiffness, with noninvasively determined coronary flow reserve (CFR) and its components, in patients with angiographically normal epicardial coronary arteries.

METHODS AND RESULTS

The study population included 398 patients without angiographic evidence of coronary stenosis, who underwent high-dose dipyridamole stress echocardiography with transthoracic-derived CFR evaluation on the left anterior descending artery. CFR was calculated as the ratio between high-dose dipyridamole and resting coronary diastolic peak velocities. Patients were divided into 2 groups: the first group included the first and second PP tertiles (n=298, PP ≤60 mm Hg) and the second group included the highest PP tertile (n=100, PP >60 mm Hg). Mean blood pressure, systolic blood pressure (both P<0.0001), age (P<0.002), and left ventricular mass index (P=0.013) were higher in the highest PP tertile, which also showed higher resting coronary flow velocity (31.6±9.6 cm/s versus 27.7±6.4 cm/s, P<0.0001) and marginally lower CFR (2.5±0.6 versus 2.6±0.6, P=0.044). Hyperemic coronary flow velocity did not differ between the 2 groups. By separate multiple linear regression analyses, after adjusting for sex, age, the highest systolic blood pressure tertile (≥140 mm Hg), left ventricular mass index, and cardiovascular risk factors, the highest PP tertile was associated with resting coronary flow velocity (P=0.003) and only marginally with hyperemic coronary flow velocity (P<0.02), whereas its association with CFR was not significant.

CONCLUSIONS

In patients without epicardial coronary artery stenosis, the highest PP tertile is associated with an increased coronary flow velocity at rest.

Reference values of brachial-ankle pulse wave velocity according to age and blood pressure in a central Asia population

BACKGROUND

Brachial-ankle pulse wave velocity (baPWV), a direct measure of aortic stiffness, has increasingly become an important assessment for cardiovascular risk. The present study established the reference and normal values of baPWV in a Central Asia population in Xinjiang, China.

METHODS

We recruited participants from a central Asia population in Xinjiang, China. We performed multiple regression analysis to investigate the determinants of baPWV. The median and 10th-90th percentiles were calculated to establish the reference and normal values based on these categories.

RESULTS

In total, 5,757 Han participants aged 15-88 years were included in the present study. Spearman correlation analysis showed that age (r = 0.587, p < 0.001) and mean blood pressure (MBP, r = 0.599, p <0.001) were the major factors influencing the values of baPWV in the reference population. Furthermore, in the multiple linear regression analysis, the standardized regression coefficients of age (0.445) and MBP (0.460) were much higher than those of body mass index, triglyceride, and glycemia (-0.054, 0.035, and 0.033, respectively). In the covariance analysis, after adjustment for age and MBP, only diabetes was the significant independent determinant of baPWV (p = 0.009). Thus, participants with diabetes were excluded from the reference value population. The reference values ranged from 14.3 to 25.2 m/s, and the normal values ranged from 13.9 to 21.2 m/s.

CONCLUSIONS

This is the first study that has established the reference and normal values for baPWV according to age and blood pressure in a Central Asia population.

Case Finding and Medical Treatment of Type 2 Diabetes among Different Ethnic Minority Groups: The HELIUS Study

Aims. Prevention of diabetes complications depends on the level of case finding and successful treatment of diabetes, which may differ between ethnicities. Therefore, we studied the prevalence by age, awareness, treatment, and control of type 2 diabetes, among a multiethnic population. Methods. We included 4,541 Dutch, 3,032 South-Asian Surinamese, 4,109 African Surinamese, 2,323 Ghanaian, 3,591 Turkish, and 3,887 Moroccan participants (aged 18-70 y) from the HELIUS study. The prevalence of diabetes was analysed by sex, ethnicity, and 10-year age groups. Ethnic differences in the prevalence, awareness, treatment, and control of diabetes were studied by logistic regression. Results. From the age of 31-40 years and older, the prevalence of diabetes was 3 to 12 times higher among ethnic minority groups than that among the Dutch host population. Awareness and medical treatment of diabetes were 2 to 5 times higher among ethnic minorities than that among Dutch. Among those medically treated, only 37-53% had HbA1c levels on target (≤7.0%); only Dutch men had HbA1c levels on target more often (67%). Conclusions. Our results suggest that the age limit for case finding among ethnic minority groups should be lower than that for the general population. Importantly, despite higher awareness and treatment among ethnic minorities, glycemic control was low, suggesting a need for increased efforts to improve the effectiveness of treatment in these groups.

Validation of the SQUASH Physical Activity Questionnaire in a Multi-Ethnic Population: The HELIUS Study

PURPOSE

To investigate the reliability and validity of the SQUASH physical activity (PA) questionnaire in a multi-ethnic population living in the Netherlands.

METHODS

We included participants from the HELIUS study, a population-based cohort study. In this study we included Dutch (n = 114), Turkish (n = 88), Moroccan (n = 74), South-Asian Surinamese (n = 98) and African Surinamese (n = 91) adults, aged 18-70 years. The SQUASH was self-administered twice to assess test-re-test reliability (mean interval 6-7 weeks) and participants wore an accelerometer and heart rate monitor (Actiheart) to enable assessment of construct validity.

RESULTS

We observed low test-re-test reliability; Intra class correlation coefficients ranged from low (0.05 for moderate/high intensity PA in African Surinamese women) to acceptable (0.78 for light intensity PA in Moroccan women). The discrepancy between self-reported and measured PA differed on the basis of the intensity of activity: self-reported light intensity PA was lower than measured but self-reported moderate/high intensity PA was higher than measured, with wide limits of agreement. The discrepancy between questionnaire and Actiheart measures of moderate intensity PA did not differ between ethnic minority and Dutch participants with correction for relevant confounders. Additionally, the SQUASH overestimated the number of participants meeting the Dutch PA norm; Cohen's kappas for the agreement were poor, the highest being 0.30 in Dutch women.

CONCLUSION

We found considerable variation in the test-re-test reliability and validity of self-reported PA with no consistency based on ethnic origin. Our findings imply that the SQUASH does not provide a valid basis for comparison of PA between ethnic groups.

Do arterial stiffness and wave reflection underlie cardiovascular risk in ethnic minorities?

Increasing evidence indicates that remarkable differences in cardiovascular risk between ethnic groups cannot be fully explained by traditional risk factors such as hypertension, diabetes or dislipidemia measured in midlife. Therefore, the underlying pathophysiology leading to this “excess risk” in ethnic minority groups is still poorly understood, and one way to address this issue is to shift the focus from “risk” to examine target organs, particularly blood vessels and their arterial properties more directly. In fact, structural and functional changes of the vascular system may be identifiable at very early stages of life when traditional factors are not yet developed. Arterial stiffening, measured as aortic pulse wave velocity, and wave reflection parameters, especially augmentation index, seem to be an important pathophysiological mechanism for the development of cardiovascular disease and predict mortality independent of other risk factors. However, data regarding these arterial indices in ethnic minorities are relatively rare and the heterogeneity between populations, techniques and statistical methods make it difficult to fully understand their role.

Prevalence and Clustering of Major Cardiovascular Risk Factors in China: A Recent Cross-Sectional Survey

Cardiovascular disease is the leading cause of death in the Chinese population. Although general prevalence estimates of cardiovascular risk factors (CVRFs) are available for Chinese adults, prevalence estimates covering all adult age groups by race/ethnicity have not been reported. The aim of this study is to estimate the current prevalence and clustering of major CVRFs in Chinese adults, including a plurality of ethnic minorities.A cross-sectional survey was conducted in a nationally representative sample of 23,010 adults aged 18 years and older from 2007 to 2011. Questionnaires and physical examinations were performed, and fasting blood was collected for laboratory measurements. The prevalence of traditional CVRFs, including hypertension, diabetes, dyslipidemia, overweight, and current smoking, were determined.The prevalence of the major CVRFs, including hypertension, diabetes, dyslipidemia, overweight, and current smoking were 24.3%, 4.3%, 49.3%, 32.0%, and 21.7%, respectively. These risk factors were significantly associated with sex, age, region, ethnicity, and education levels. Overall, 70.3%, 40.3%, and 16.7% of Chinese adults had ≥1, ≥2, or ≥3 CVRFs, respectively. Men, northern and rural residents were more likely to have clustered CVRFs compared with women, southern and urban residents, respectively. Compared with Han residents, Hui and Mongolian residents were more likely, and Tujia and Miao residents were less likely, to have ≥1, ≥2, or ≥3 risk factors. The prevalence of Chinese women having ≥1, ≥2, or ≥3 CVRFs decreased with increasing levels of education.The prevalence and clustering of CVRFs is still high in Chinese adults ≥18 years old, especially in men and in individuals living in the northern and rural areas. Of note, there are differences in cardiovascular risk among different ethnic groups. Therefore, targeted and enhanced intervention measures are required to reduce the risk of cardiovascular disease and the corresponding economic burden of disease in China.

Relationship between sleep duration and arterial stiffness in a multi-ethnic population: The HELIUS study

We examined the relationship between sleep duration and arterial stiffness among a multi-ethnic cohort, and whether the associations differed among ethnic minority groups in the Netherlands. Data were derived from 10 994 participants (aged 18-71 years) of the Healthy Life in an Urban Setting (HELIUS) study. Self-reported sleep duration was categorized into: short (<7 h/night), healthy (7-8 h/night) and long (≥9 h/night). Arterial stiffness was assessed by duplicate pulse-wave velocity (PWV in m/s) measurements using the Arteriograph system. The association of sleep duration with PWV was analysed using linear regression (β) with 95% confidence interval (CI). Results showed that neither short nor long sleep was related to PWV in all ethnic groups, except for long sleep in Dutch men which was associated with higher PWV (indicating stiffer arteries) after adjustment for potential confounders (β = 0.67, 95%CI, 0.23-1.11). Our study showed no convincing evidence that sleep duration was related to arterial stiffness among various ethnic groups. The link between sleep duration and cardiovascular outcomes does not seem to operate through arterial stiffness. Further research is needed to consolidate these findings.