Ethnicity modifies the association between diabetes mellitus and ischaemic heart disease in Chinese, Malays and Asian Indians living in Singapore

Risk prediction models for type 2 diabetes using either fasting plasma glucose or HbA1c in Chinese, Malay, and Indians: Results from three multi-ethnic Singapore cohorts

AIMS

To assess three well-established type 2 diabetes (T2D) risk prediction models based on fasting plasma glucose (FPG) in Chinese, Malays, and Indians, and to develop simplified risk models based on either FPG or HbA1c.

METHODS

We used a prospective multiethnic Singapore cohort to evaluate the established models and develop simplified models. 6,217 participants without T2D at baseline were included, with an average follow-up duration of 8.3 years. The simplified risk models were validated in two independent multiethnic Singapore cohorts (N = 12,720).

RESULTS

The established risk models had moderate-to-good discrimination (area under the receiver operating characteristic curves, AUCs 0.762 - 0.828) but a lack of fit (P-values < 0.05). Simplified risk models that included fewer predictors (age, BMI, systolic blood pressure, triglycerides, and HbA1c or FPG) showed good discrimination in all cohorts (AUCs ≥ 0.810), and sufficiently captured differences between the ethnic groups. While recalibration improved fit the simplified models in validation cohorts, there remained evidence of miscalibration in Chinese (p ≤ 0.012).

CONCLUSIONS

Simplified risk models including HbA1c or FPG had good discrimination in predicting incidence of T2D in three major Asian ethnic groups. Risk functions with HbA1c performed as well as those with FPG.

Differences in type 2 diabetes risk between East, South, and Southeast Asians living in Singapore: the multi-ethnic cohort

INTRODUCTION

Prospective data on differences in type two diabetes (T2D) risk between Asian ethnic groups are sparse. We, therefore, compared T2D risk for East (Chinese), South (Indian), and Southeast (Malay) Asians and examined biological factors that may contribute to ethnic differences.

RESEARCH DESIGN AND METHODS

We included 7427 adults of Chinese, Malay, and Indian origin participating in the Singapore multi-ethnic cohort. Information on sociodemographic, lifestyle, and biological risk factors (body mass index (BMI), waist circumference, blood lipids, blood pressure, C reactive protein, adiponectin, and homeostasis model assessment for insulin resistance and beta-cell function) were collected using standardized interviews and physical examinations. T2D cases were based on physician diagnoses, a national medical registry, fasting plasma glucose, or glycated hemoglobin A1c. We used multivariable logistic association and mediation analyses.

RESULTS

During an average follow-up of 7.2 years (SD 2.2 years), we documented 595 cases of incident diabetes. Ethnic Malays (OR 2.08, 95% CI 1.69 to 2.56) and Indians (OR 2.22, 95% CI 1.80 to 2.74) had an approximately twofold higher risk of T2D compared with ethnic Chinese. Higher BMI explained the higher risk for Malay compared with Chinese ethnicity. Higher BMI, waist circumference, inflammation, and insulin resistance, and lower beta-cell function and high-density lipoprotein-cholesterol significantly contributed to the higher T2D risk for Indian compared with Chinese ethnicity. However, part of the higher T2D risk associated with Indian ethnicity remained unexplained. Despite their lower diabetes risk, Chinese participants had the lowest adiponectin levels.

CONCLUSIONS

Different Asian ethnic groups have unique biological risk factor profiles related to T2D development that may warrant targeted approaches for prevention and treatment.

Comparing the pooled cohort equations and coronary artery calcium scores in a symptomatic mixed Asian cohort

Background

The value of pooled cohort equations (PCE) as a predictor of major adverse cardiovascular events (MACE) is poorly established among symptomatic patients. Coronary artery calcium (CAC) assessment further improves risk prediction, but non-Western studies are lacking. This study aims to compare PCE and CAC scores within a symptomatic mixed Asian cohort, and to evaluate the incremental value of CAC in predicting MACE, as well as in subgroups based on statin use.

Methods

Consecutive patients with stable chest pain who underwent cardiac computed tomography were recruited. Logistic regression was performed to determine the association between risk factors and MACE. Cohort and statin-use subgroup comparisons were done for PCE against Agatston score in predicting MACE.

Results

Of 501 patients included, mean (SD) age was 53.7 (10.8) years, mean follow-up period was 4.64 (0.66) years, 43.5% were female, 48.3% used statins, and 50.0% had no CAC. MI occurred in 8 subjects while 9 subjects underwent revascularization. In the general cohort, age, presence of CAC, and ln(Volume) (OR = 1.05, 7.95, and 1.44, respectively) as well as age and PCE score for the CAC = 0 subgroup (OR = 1.16 and 2.24, respectively), were significantly associated with MACE. None of the risk factors were significantly associated with MACE in the CAC > 0 subgroup. Overall, the PCE, Agatston, and their combination obtained an area under the receiver operating characteristic curve (AUC) of 0.501, 0.662, and 0.661, respectively. Separately, the AUC of PCE, Agatston, and their combination for statin non-users were 0.679, 0.753, and 0.734, while that for statin-users were 0.585, 0.615, and 0.631, respectively. Only the performance of PCE alone was statistically significant (p = 0.025) when compared between statin-users (0.507) and non-users (0.783).

Conclusion

In a symptomatic mixed Asian cohort, age, presence of CAC, and ln(Volume) were independently associated with MACE for the overall subgroup, age and PCE score for the CAC = 0 subgroup, and no risk factor for the CAC > 0 subgroup. Whilst the PCE performance deteriorated in statin versus non-statin users, the Agatston score performed consistently in both groups.

Evaluating the Coronary Artery Disease Consortium Model and the Coronary Artery Calcium Score in Predicting Obstructive Coronary Artery Disease in a Symptomatic Mixed Asian Cohort

Background

The utility of a given pretest probability score in predicting obstructive coronary artery disease (CAD) is population dependent. Previous studies investigating the additive value of coronary artery calcium (CAC) on pretest probability scores were predominantly limited to Western populations. This retrospective study seeks to evaluate the CAD Consortium (CAD2) model in a mixed Asian cohort within Singapore with stable chest pain and to evaluate the incremental value of CAC in predicting obstructive CAD.

Methods and Results

Patients who underwent cardiac computed tomography and had chest pain were included. The CAD2 clinical model comprised of age, sex, symptom typicality, diabetes, hypertension, hyperlipidemia, and smoking status and was compared with the CAD2 extended model that added CAC to assess the incremental value of CAC scoring, as well as to the corresponding locally calibrated local assessment of the heart models. A total of 522 patients were analyzed (mean age 54±11 years, 43.1% female). The CAD2 clinical model obtained an area under the curve of 0.718 (95% CI, 0.668–0.767). The inclusion of CAC score improved the area under the curve to 0.896 (95% CI, 0.867–0.925) in the CAD2 models and from 0.767 (95% CI, 0.721–0.814) to 0.926 (95% CI, 0.900–0.951) in the local assessment of the heart models. The locally calibrated local assessment of the heart models showed better discriminative performance than the corresponding CAD2 models (P<0.05 for all).

Conclusions

The CAD2 model was validated in a symptomatic mixed Asian cohort and local calibration further improved performance. CAC scoring provided significant incremental value in predicting obstructive CAD.

Role of diabetes in stroke: Recent advances in pathophysiology and clinical management

The increasing prevalence of diabetes and stroke is a major global public health concern. Specifically, acute stroke patients, with pre-existing diabetes, pose a clinical challenge. It is established that diabetes is associated with a worse prognosis after acute stroke and the various biological factors that mediate poor recovery profiles in diabetic patients is unknown. The level of association and impact of diabetes, in the setting of reperfusion therapy, is yet to be determined. This article presents a comprehensive overview of the current knowledge of the role of diabetes in stroke, therapeutic strategies for primary and secondary prevention of cardiovascular disease and/or stroke in diabetes, and various therapeutic considerations that may apply during pre-stroke, acute, sub-acute and post-stroke stages. The early diagnosis of diabetes as a comorbidity for stroke, as well as tailored post-stroke management of diabetes, is pivotal to our efforts to limit the burden. Increasing awareness and involvement of neurologists in the management of diabetes and other cardiovascular risk factors is desirable towards improving stroke prevention and efficacy of reperfusion therapy in acute stroke patients with diabetes.

Adult-onset diabetes in Middle Eastern immigrants to Sweden: Novel subgroups and diabetic complications-The All New Diabetes in Scania cohort diabetic complications and ethnicity

BACKGROUND

Middle Eastern immigrants to Europe represent a high risk population for type 2 diabetes. We compared prevalence of novel subgroups and assessed risk of diabetic macro- and microvascular complications between diabetes patients of Middle Eastern and European origin.

METHODS

This study included newly diagnosed diabetes patients born in Sweden (N = 10641) or Iraq (N = 286), previously included in the All New Diabetes in Scania cohort. The study was conducted between January 2008 and August 2016. Patients were followed to April 2017. Incidence rates in diabetic macro- and microvascular complications were assessed using cox-regression adjusting for the confounding effect of age at onset, sex, anthropometrics, glomerular filtration rate (eGFR) and HbA1c.

FINDINGS

In Iraqi immigrants versus native Swedes, severe insulin-deficient diabetes was almost twice as common (27.9 vs. 16.2% p < 0.001) but severe insulin-resistant diabetes was less prevalent. Patients born in Iraq had higher risk of coronary events (hazard ratio [HR] 1.84, 95% CI 1.06-3.12) but considerably lower risk of chronic kidney disease (CKD) than Swedes (HR 0.19; 0.05-0.76). The lower risk in Iraqi immigrants was partially attributed to better eGFR. Genetic risk scores (GRS) showed more genetic variants associated with poor insulin secretion but lower risk of insulin resistance in the Iraqi than native Swedish group.

INTERPRETATION

People with diabetes, born in the Middle East present with a more insulin-deficient phenotype and genotype than native Swedes. They have a higher risk of coronary events but lower risk of CKD. Ethnic differences should be considered in the preventive work towards diabetes and its complications.

Incidence and Predictors of Dysglycemia and Regression to Normoglycemia in Indian Adolescents and Young Adults: 10-Year Follow-Up of the ORANGE Study

Background: The prevalence of diabetes in youth is increasing worldwide in parallel with the obesity epidemic. This study aimed to determine the incidence rates of dysglycemia (diabetes or prediabetes) and evaluate the predictors of its progression or regression to normal glucose tolerance (NGT) in a cohort of children and adolescents studied in Chennai, South India. Methods: A longitudinal follow-up of the Obesity Reduction and Awareness of Noncommunicable Diseases through Group Education (ORANGE) cohort was performed after a median of 7.1 years (n = 845; 5928 person-years of follow-up). To determine their diabetes status at follow-up, participants underwent an oral glucose tolerance test (n = 811 with NGT and 34 with prediabetes at baseline), excluding those with diabetes at baseline. Incidence rates for dysglycemia were reported per 1000 person-years of follow-up. Cox proportional hazards model was used to estimate the predictors of progression and regression. Results: Out of 811 individuals with NGT at baseline, 115 developed dysglycemia giving an incidence rate of 20.2 per 1000 person-years (95% confidence interval: 16.8-24.2). Among those with prediabetes at baseline, 70.6% of the individuals converted to NGT and the remaining 29.4% either got converted to diabetes or remained as prediabetes. Higher age, body mass index, fasting plasma glucose, 2-hour plasma glucose (2-h PG), positive family history of diabetes, and systolic blood pressure (BP) were independent predictors of incident dysglycemia, whereas lower age, waist circumference, 2-h PG, systolic BP, and triglycerides predicted regression to normoglycemia. Conclusions: This study highlights the growing burden of dysglycemia in Asian Indian youth and emphasizes the need for targeted preventive actions.

Factors associated with health-related quality of life in a working population in Singapore

OBJECTIVES

This study aimed to evaluate the determinants of health-related quality of life (HRQoL) among workers in Singapore.

METHODS

We analysed data from a cross-sectional study of 464 participants from 4 companies in Singapore. Physical and mental components of HRQoL were assessed using the Short-Form 36 version 2.0 survey. A generalized linear model was used to determine factors associated with the physical component summary (PCS) and mental component summary (MCS) scores of HRQoL.

RESULTS

The overall mean PCS and MCS scores were mean±standard deviation 51.6±6.7 and 50.2±7.7, respectively. The scores for subscales ranged from 62.7±14.7 for vitality to 83.5±20.0 for role limitation due to emotional problems. Ethnicity, overweight/obesity, and years working at the company were significantly associated with physical HRQoL, and age and stress at work were significantly associated with mental HRQoL. Moreover, sleep quality was significantly associated with both physical and mental HRQoL.

CONCLUSIONS

These findings could help workplaces in planning strategies and initiatives for employees to maintain a worklife balance that encompasses their physical, emotional, and social well-being.

Patterns and Risk Factor Profiles of Visual Loss in a Multiethnic Asian Population: The Singapore Epidemiology of Eye Diseases Study

PURPOSE

To describe the pattern and risk factor traits associated with visual loss (defined as either visual impairment [VI] or blindness) in a multiethnic Asian cohort of Malay, Indian, and Chinese individuals living in Singapore.

METHODS

A total of 10 020 participants from the Singapore Epidemiology of Eye Diseases Study were examined between 2004 and 2011. All underwent standardized examinations. VI (visual acuity <20/40 to ≥20/200) and blindness (visual acuity <20/200) were defined based on the US definition, better-seeing eye. Singapore Population Census 2010 was used to calculate age-standardized prevalence. Multiple logistic regression analysis was performed to determine the independent and joint risk factors associated with visual loss.

RESULTS

Malay individuals had higher age-standardized prevalence of best-corrected and presenting VI (5.4% and 19.9%, respectively) than Indian (3.6% and 18.0%) and Chinese individuals (3.3% and 17.2%). Cataract was the main cause for presenting and best-corrected blindness; cataract and diabetic retinopathy were the top causes for best-corrected VI, consistently observed across the 3 ethnic groups. Older age, female sex, lower socioeconomic status, diabetes, systemic comorbidities, and cognitive impairment were independently associated with increased risk of best-corrected visual loss (all P ≤ .027). Individuals aged ≥60 years with diabetes were 12.7 times (95% confidence interval, 8.39-19.23) likely to have best-corrected visual loss, compared with younger, nondiabetic individuals. Lower income and education explained 58.1% and 23.2% of best-corrected visual loss in this population, respectively.

CONCLUSION

In this urban multiethnic Asian population, we identified common traits associated with visual loss across Malay, Indian, and Chinese individuals. These results will be useful for the planning and designing of eye health services and strategies for Asia's rapidly developing populations living in urban communities. NOTE: Publication of this article is sponsored by the American Ophthalmological Society.

Sociodemographic factors in relation to hypertension prevalence, awareness, treatment and control in a multi-ethnic Asian population: a cross-sectional study

OBJECTIVES

Literature suggested that multi-ethnic Western populations experienced differential hypertension outcomes, but evidence is limited in Asia. This study was aimed to determine sociodemographic correlates of hypertension and its awareness, treatment and control among a multi-ethnic Asian population living in Singapore.

SETTING

We used cross-sectional data of participants from the Multi-Ethnic Cohort (MEC) (n=14 530) recruited in Singapore between 2004 and 2010.

PARTICIPANTS

Participants who completed questionnaire and attended health examination, without cardiovascular diseases, cancer, stroke, renal failure, asthma and mental illnesses were included in the study. Multivariable logistic regression models were used to determine sociodemographics factors associated with hypertension, unawareness of having hypertension, untreated and uncontrolled hypertension.

RESULTS

Among 10 215 participants (47.2% Chinese, 26.0% Malay and 26.8% Indian), hypertension prevalence was estimated to be 31.1%. Older age, Malay ethnicity, male, lower educational level and being homemaker or retired/unemployed were factors significantly associated with hypertension. Stratified analysis suggested that age and education were consistently associated with hypertension across all ethnic groups. The proportions of being unaware, untreated and uncontrolled were 49.0%, 25.2% and 62.4%, respectively. Ethnicity and younger age were associated with unawareness; younger age, male and lower educational level were associated with untreated hypertension and older age was associated with uncontrolled hypertension.

CONCLUSIONS

In this study, ethnic differences in relation to hypertension were associated with sociodemographic variability in ethnic groups. Age and educational level were consistent correlates of hypertension in all ethnic groups. Unawareness and uncontrolled hypertension were common in this Asian population and associated with sociodemographic factors. More targeted strategies may be required to overcome the observed disparities.

Clinical management of type 2 diabetes in south Asia

Compared with other ethnic groups, south Asian people with type 2 diabetes tend to develop the disease at a younger age and manifest with higher glycaemia, dyslipidaemia, nephropathy, and cardiovascular diseases. Additionally, specific issues that can affect treatment of type 2 diabetes in south Asia include poor awareness of the disease, delay in diagnosis, inadequate treatment, the use of ineffective and often harmful alternative medicines, and frequent non-compliance with lifestyle recommendations and drug treatment. Disease development at younger ages, delayed diagnosis, and inadequate management result in early development of severe complications and premature mortality. In this Series paper, we describe the challenges associated with the increasing burden of type 2 diabetes in south Asia and discuss ways to improve clinical care of people with the disorder in the region (defined to include Bangladesh, Bhutan, India, Nepal, Pakistan, and Sri Lanka). Treatment of diabetes in south Asia needs to be individualised on the basis of diverse and heterogeneous lifestyle, phenotype, environmental, social, cultural, and economic factors. Aggressive management of risk factors from diagnosis is necessary to reduce the risk of microvascular and macrovascular complications, focusing on provision of basic treatments (eg, metformin, low-cost statins, and blood pressure-lowering drugs) and other interventions such as smoking cessation. Strengthening of the primary care model of care, better referral linkages, and implementation of rehabilitation services to care for patients with chronic complications will be important. Finally, improvement of physicians' skills, provision of relevant training to non-physician health-care workers, and the development and regular updating of national clinical management guidelines will also be crucial to improve diabetes care in the region.

Six-Year Incidence of and Risk Factors for Cataract Surgery in a Multi-ethnic Asian Population: The Singapore Epidemiology of Eye Diseases Study

PURPOSE

To report the 6-year incidence of cataract surgery in an Asian population-based cohort of Malay, Indian, and Chinese persons living in Singapore and factors associated with undergoing cataract surgery over the follow-up period.

DESIGN

Population-based prospective cohort study.

PARTICIPANTS

From 2004 through 2011, 10 033 participants (3280 Malays, 3400 Indians, and 3353 Chinese) 40 years of age or older participated in the Singapore Epidemiology of Eye Diseases Study. Six years later, 6762 participants (78.7% of those eligible, including 1901 Malays [72.1% of eligible], 2200 Indians [75.5% of eligible], and 2661 Chinese [87.7% of eligible]) were re-examined.

METHODS

Detailed eye examinations including slit-lamp biomicroscopy were conducted at both visits. Logistic regression models were used to assess factors associated with cataract surgery after adjusting for age, gender, socioeconomic status, and other risk factors.

MAIN OUTCOME MEASURE

Incident cataract surgery.

RESULTS

The age-adjusted 6-year incidence of cataract surgery was 11.0% (9.5%, 12.6%, and 11.1% for Malays, Indians, and Chinese, respectively) and was strongly age related (P < 0.001 for trend). After adjustment, baseline factors associated with incident cataract surgery included older age (odds ratio [OR], 1.13 per 1-year increase; 95% confidence interval [CI], 1.11-1.14), diabetes (OR, 1.90; 95% CI, 1.54-2.33), myopia (OR, 1.78; 95% CI, 1.44-2.20), and baseline presence of any cataract, including nuclear cataract (OR, 3.78; 95% CI, 2.91-4.89), cortical cataract (OR, 3.01; 95% CI, 2.45-3.71), and posterior subcapsular cataract (OR, 5.00; 95% CI, 3.91-6.41). The population attributable risks of cataract surgery related to diabetes and myopia were 17.6% and 19.1%, respectively.

CONCLUSIONS

One in 10 Malay, Indian, and Chinese Singaporeans 40 years of age or older underwent cataract surgery in at least 1 eye over 6 years. In Asian populations, diabetes and myopia, 2 well-known factors associated with cataract prevalence, are significant and potentially modifiable factors associated with the need for cataract surgery.

Ethnicity influences cardiovascular outcomes and complications in patients with type 2 diabetes

AIM

To determine whether cardiovascular outcomes in type 2 diabetes (T2D) differ according to ethnicity, and whether ethnicity influences the effect of gender on these outcomes in Caucasians, East-Southeast-Asians, Middle-Easterners, South-Asians and Pacific-Islanders.

METHODS

We compared demographics, HbA1c, lipid profile, renal function markers, and prevalence of macrovascular and microvascular complications between ethnic groups. Cross-sectional data was prospectively collected from 204 consecutive patients at Westmead Hospital's T2D clinic from April-October 2015. Univariate analysis was performed using chi-squared test for categorical data, and Mann-Whitney-U or Kruskal-Wallis test for continuous data.

RESULTS

Compared to Caucasians, South-Asians were diagnosed younger, were currently younger, had lower body-mass-index (BMI) and better renal function but higher rates of non-ST-elevation myocardial infarction (STEMI, 21.7% versus 3.5%, p<0.05). East-Southeast-Asians had lower BMI but more nephropathy than Caucasians (59% versus 39%, p<0.05). East-Southeast-Asian males had fewer CVD than Caucasians, but this protection was absent in East-Southeast-Asian females. Middle-Easterners had more non-STEMI than Caucasians (5.3% vs 3.5%, p<0.05). Middle-Eastern females were not at lower CVD risk than males. Caucasians had most PVD (20% versus 6%, p<0.05).

CONCLUSIONS

Ethnicity influences rates of diabetes-related complications. Female CVD protection is altered in some groups. Ethnicity should be considered in assessing CVD and complications risk.

Poor glycaemic control and its metabolic and demographic risk factors in a Malaysian community-based study

OBJECTIVES

The lack of population-based evidence on the risk factors for poor glycaemic control in diabetics, particularly in resource-poor settings, is a challenge for the prevention of long-term complications. This study aimed to identify the metabolic and demographic risk factors for poor glycaemic control among diabetics in a rural community in Malaysia.

METHODS

A total of 1844 (780 males and 1064 females) known diabetics aged ≥ 35 years were identified from the South East Asia Community Observatory (SEACO) health and demographic surveillance site database.

RESULTS

41.3% of the sample had poor glycaemic control. Poor glycaemic control was associated with age and ethnicity, with older participants (65+) better controlled than younger adults (45-54), and Malaysian Indians most poorly controlled, followed by Malay and then Chinese participants. Metabolic risk factors were also highly associated with poor glycaemic control.

CONCLUSIONS

There is a critical need for evidence for a better understanding of the mechanisms of the associations between risk factors and glycaemic control.

Correlates of occupational, leisure and total sitting time in working adults: results from the Singapore multi-ethnic cohort

Background

Evidence on the health risks of sitting is accumulating. However, research identifying factors influencing sitting time in adults is limited, especially in Asian populations. This study aimed to identify socio-demographic and lifestyle correlates of occupational, leisure and total sitting time in a sample of Singapore working adults.

Methods

Data were collected between 2004 and 2010 from participants of the Singapore Multi Ethnic Cohort (MEC). Medical exclusion criteria for cohort participation were cancer, heart disease, stroke, renal failure and serious mental illness. Participants who were not working over the past 12 months and without data on sitting time were excluded from the analyses. Multivariable regression analyses were used to examine cross-sectional associations of self-reported age, gender, ethnicity, marital status, education, smoking, caloric intake and moderate-to-vigorous leisure time physical activity (LTPA) with self-reported occupational, leisure and total sitting time. Correlates were also studied separately for Chinese, Malays and Indians.

Results

The final sample comprised 9384 participants (54.8% male): 50.5% were Chinese, 24.0% Malay, and 25.5% Indian. For the total sample, mean occupational sitting time was 2.71 h/day, mean leisure sitting time was 2.77 h/day and mean total sitting time was 5.48 h/day. Sitting time in all domains was highest among Chinese. Age, gender, education, and caloric intake were associated with higher occupational sitting time, while ethnicity, marital status and smoking were associated with lower occupational sitting time. Marital status, smoking, caloric intake and LTPA were associated with higher leisure sitting time, while age, gender and ethnicity were associated with lower leisure sitting time. Gender, marital status, education, caloric intake and LTPA were associated with higher total sitting time, while ethnicity was associated with lower total sitting time. Stratified analyses revealed different associations within sitting domains for Indians compared to Chinese and Malays.

Conclusion

Our findings highlight the need to focus on separate domains of sitting (occupational, leisure or total) when identifying which factors determine this behavior, and that the content of intervention programs should be tailored to domain-specific sitting rather than to sitting in general. Finally, our study showed ethnic differences and therefore we recommend to culturally target interventions.

Obesity, Diabetes, and Acute Coronary Syndrome: Differences Between Asians and Whites

BACKGROUND

Most diabetes and cardiovascular studies have been conducted in white patients, with data being extrapolated to other population groups.

METHODS

For this analysis, patient-level data were extracted from 5 randomized clinical trials in patients with acute coronary syndrome; we compared obesity levels between Asian and white populations, stratified by diabetes status. By using an adjusted Cox proportional hazards model, hazard ratios (HRs) for cardiovascular outcomes after an acute coronary syndrome were determined.

RESULTS

We identified 49,224 patient records from the 5 trials, with 3176 Asians and 46,048 whites. Whites with diabetes had higher body mass index values than those without diabetes (median 29.3 vs 27.2 kg/m²; P < .0001), whereas Asians with diabetes and without diabetes had similar body mass index (24.7 vs 24.2 kg/m²). Asians with diabetes (HR, 1.63; 95% confidence interval [CI], 1.32-2.02), whites with diabetes (HR, 1.15; 95% CI, 1.06-1.25), and Asians without diabetes (HR, 1.36; 95% CI, 1.14-1.64) had higher rates of the composite of death, myocardial infarction, or stroke at 30 days than whites without diabetes. Asians with diabetes (HR, 1.84; 95% CI, 1.47-2.31), whites with diabetes (HR, 1.47; 95% CI, 1.33-1.62), and Asians without diabetes (HR, 1.38; 95% CI, 1.11-1.73) had higher rates of death at 1 year compared with whites without diabetes. There were no significant interactions between race and diabetes for ischemic outcomes.

CONCLUSIONS

Although Asians with diabetes and acute coronary syndrome are less likely to be obese than their white counterparts, their risk for death or recurrent ischemic events was not lower.

Ethnic Differences in the Risk Factors and Severity of Coronary Artery Disease: a Patient-Based Study in Iran

Background

Diverse ethnic groups may differ regarding the risk factors and severity of coronary artery disease (CAD). This study sought to assess the association between ethnicity and CAD risk and severity in six major Iranian ethnic groups.

Methods

In this study, 20,165 documented coronary artery disease patients who underwent coronary angiography at a tertiary referral heart center were recruited. The demographic, laboratory, clinical, and risk factor data of all the patients were retrieved. The Gensini score (an indicator of CAD severity) was calculated for all, and the risk factors and severity of CAD were compared between the ethnical groups, using adjusted standardized residuals, Kruskal–Wallis test, and multivariable regression analysis.

Results

The mean age of the participants (14,131 [70.1%] men and 6034 [29.9%] women) was 60.7 ± 10.8 years. The Fars (8.7%) and Gilak (8.6%) ethnic groups had the highest prevalence of ≥4 simultaneous risk factors. The mean Gensini score was the highest for the Gilaks (77.1 ± 55.9) and the lowest among the Lors (67.5 ± 52.8). The multivariable regression analysis showed that the Gilaks had the worst severity (β 0.056, 95% CI 0.009 to 0.102; P = 0.018), followed by the Torks (β 0.032, 95% CI 0.005 to 0.059; P = 0.020). Meanwhile, the Lors showed the lowest severity (β −0.087, 95% CI −0.146 to −0.027; P = 0.004).

Conclusions

This study found that there was heterogeneity in CAD severity and a diverse distribution in its well-known traditional risk factors among major Iranian ethnic groups.

Exercise and eating habits among urban adolescents: a cross-sectional study in Kolkata, India

BACKGROUND

Unhealthy eating and lack of exercise during adolescence culminated into earlier onset and increasing burden of atherosclerotic cardiovascular diseases (CVDs) worldwide. Among urban Indian adolescents, prevalence of these risk factors of CVD seemed to be high, but data regarding their pattern and predictors was limited. To address this dearth of information, a survey was conducted among urban adolescent school-students in Kolkata, a highly populated metro city in eastern India.

METHODS

During January-June, 2014, 1755 students of 9th-grade were recruited through cluster (schools) random sampling. Informed consents from parents and assents from adolescents were collected. Information on socio-demographics, CVD-related knowledge and perception along with eating and exercise patterns were collected with an internally validated structured questionnaire. Descriptive and regression analyses were performed in SAS-9.3.2.

RESULTS

Among 1652 participants (response rate = 94.1%), about 44% had poor overall knowledge about CVD, 24% perceived themselves as overweight and 60% considered their general health as good. Only 18% perceived their future CVD-risk and 29% were engaged in regular moderate-to-vigorous exercise. While 55% skipped meals regularly, 90% frequently consumed street-foods and 54% demonstrated overall poor eating habits. Males were more likely to engage in moderate-to-vigorous exercise [adjusted odds ratio (AOR) = 3.40(95% confidence interval = 2.55-4.54)] while students of higher SES were less likely [AOR = 0.59(0.37-0.94)]. Males and those having good CVD-related knowledge were more likely to exercise at least 1 h/day [AOR = 7.77(4.61-13.07) and 2.90(1.46-5.78) respectively]. Those who perceived their future CVD-risk, skipped meals more [2.04(1.28-3.25)] while Males skipped them less [AOR = 0.62(0.42-0.93)]. Subjects from middle class ate street-foods less frequently [AOR = 0.45(0.24-0.85)]. Relatively older students and those belonging to higher SES were less likely to demonstrate good eating habits [AOR = 0.70(0.56-0.89) and 0.23(0.11-0.47) respectively]. A large knowledge-practice gap was evident as students with good CVD-related knowledge were less likely to have good eating habits [AOR = 0.55(0.32-0.94)].

CONCLUSIONS

CVD-related knowledge as well as eating and exercise habits were quite poor among adolescent school-students of Kolkata. Additionally, there was a large knowledge-practice gap. Multi-component educational interventions targeting behavioral betterment seemed necessary for these adolescents to improve their CVD-related knowledge, along with appropriate translation of knowledge into exercise and eating practices to minimize future risk of CVDs.

Coronary atherosclerotic plaque burden and composition by CT angiography in Caucasian and South Asian patients with stable chest pain

AIMS

South Asian (SA) patients are known to have an increased incidence of acute cardiovascular events compared with Caucasians. The aim of this observational study was to compare the prevalence of coronary stenoses, the amount and composition of coronary atherosclerosis in a cohort of Caucasian and SA patients with stable chest pain, in non-acute settings.

METHODS AND RESULTS

The study protocol conformed to the ethical guidelines of the 1975 Declaration of Helsinki. In 963 consecutive Caucasian and SA patients undergoing coronary computed tomography angiography, atherosclerotic plaques were quantified using a semi-automated algorithm. The vessel per cent diameter and area stenosis were measured. Plaque composition was examined from the measurement of calcified, non-calcified, and total plaque burden. There were 420 Caucasian (238 males) and 543 SA (297 males) patients. Caucasian patients were older than SA patients (54.39 ± 11.65 vs. 49.83 ± 11.03 years) and had lower prevalence of diabetes (13.13 vs. 32.41%) and hyperlipidaemia (56.90 vs. 68.51%) (all P-values <0.001). After adjusting for differences in cardiovascular risk factors, there were no differences in per cent diameter and area stenosis, and no difference in the proportions of patients with one-, two-, or three-vessel disease. There was no difference in total plaque burden; however, the per cent non-calcified plaque composition was lower in Caucasians compared with SA (80.95 vs. 90.42%; P-value <0.001).

CONCLUSION

This study conducted in non-acute settings showed an ethnic difference in composition of coronary atherosclerotic plaque with lower non-calcified composition in Caucasian patients compared with SA patients, which was independent of age, diabetes, hyperlipidaemia, and the other available cardiovascular risk factors.

Ethnic disparities in risk of cardiovascular disease, end-stage renal disease and all-cause mortality: a prospective study among Asian people with Type 2 diabetes

AIM

To study prospectively the ethnic-specific risks of cardiovascular disease, end-stage renal disease and all-cause mortality in patients with Type 2 diabetes mellitus among native Asian subpopulations.

METHODS

A total of 2337 subjects with Type 2 diabetes (70% Chinese, 17% Malay and 13% Asian Indian) were followed for a median of 4.0 years. Time-to-event analysis was used to study the association of ethnicity with adverse outcomes.

RESULTS

Age- and gender-adjusted hazard ratios for cardiovascular disease in ethnic Malay and Asian Indian subjects were 2.01 (1.40-2.88; P<0.0001) and 1.60 (1.07-2.41; P=0.022) as compared with Chinese subjects. Adjustment for conventional cardiovascular disease risk factors, including HbA1c , blood pressure and lipid profile, slightly attenuated the hazards in Malay (1.82, 1.23-2.71; P=0.003) and Asian Indian subjects (1.47, 0.95-2.30; P=0.086); However, further adjustment for baseline renal function (estimated GFR) and albuminuria weakened the cardiovascular disease risks in Malay (1.48, 0.98-2.26; P=0.065) but strengthened that in Asian Indian subjects (1.81, 1.14-2.87; P=0.012). Competing-risk regression showed that the age- and gender-adjusted sub-distribution hazard ratio for end-stage renal disease was 1.87 (1.27-2.73; P=0.001) in Malay and 0.39 (0.18-0.83; P=0.015) in Asian Indian subjects. Notably, the difference in end-stage renal disease risk among the three ethnic groups was abolished after further adjustment for baseline estimated GFR and albuminuria. There was no significant difference in risk of all-cause mortality among the three ethnic groups.

CONCLUSIONS

Risks of cardiovascular and end-stage renal diseases in native Asian subjects with Type 2 diabetes vary substantially among different ethnic groups. Differences in prevalence of diabetic kidney disease may partially explain the ethnic disparities.

Long-term diabetes outcomes in multi-ethnic Asians living in Singapore

AIMS

This study aims to assess ethnic and gender disparities on long-term complications among multi-ethnic Asians with Diabetes Mellitus (DM) living in Singapore.

METHODS

We conducted a retrospective cohort study involving 3006 patients who attended a diabetes centre in a hospital from 2003 to 2011. Demographics and clinical data were obtained from standardised questionnaire and patient's case records. Age at onset of diabetes was calculated as current age minus duration of DM in years. Outcomes on Acute Myocardial Infarction (AMI), End-Stage Renal Failure (ESRF) and all-cause death were ascertained by data linkage with national registries.

RESULTS

The mean duration of diabetes exposure was 15.6 ± 9.1 years for AMI, 15.4 ± 9.0 years for ESRF and 17.0 ± 9.0 years for death. After adjusting for traditional cardiovascular risk factors, Malay and Indian with diabetes remained significantly associated with AMI with HRs 2.81(95%CI, 1.81-4.37) and 2.03 (95%CI, 1.15-3.59), respectively. The effect of Malays on ESRF and death became attenuated post-adjustment. Besides mortality, there was preponderance for other adverse outcomes associated with male.

CONCLUSIONS

Ethnic (Malay worse) and gender (male worse) disparities were observed in DM-related outcomes. The results may inform allocation of finite resources and to organize care targeted at high-risk groups.

Trends in the incidence and mortality of coronary heart disease in asian pacific region: the Singapore experience

The rates of coronary heart disease are lower in Asia than in developed countries. Singapore has undergone rapid urbanization over the past several decades. In the several decades between the 1960s and 1980s, a rapid increase in the rates of ischemic heart disease was observed, to the extent that Singapore exhibits one of the highest rates of mortality from cardiovascular disease in the Asia-Pacific region, higher even than the rates in North America. Rates of cardiovascular disease have now stabilized, and are declining. This is, a pattern that has been observed in many developed countries. Increased life expectancy has resulted in an epidemiologic transition that has seen chronic non-communicable diseases replace malnutrition and infections as the major causes of mortality. At the same time, there have been changes in nutrient intake and physical activity as well as rapid increases in the levels of several cardiovascular risk factors including obesity, hypertension, hyperlipidemia, diabetes mellitus and systemic inflammation. Furthermore, when present, there is a lack of awareness and sub-optimal treatment of these risk factors. In addition to the changes in environmental exposures related to socio-economic development, it does appear that specific populations are particularly prone to the development of cardiovascular disease and its risk factors. In particular, Asian Indians experience a high rate of coronary heart disease and diabetes mellitus. Emerging data suggests that Chinese may be particularly prone to the adverse effects of obesity in relation to insulin resistance and inflammation. A concerted effort to change lifestyles to prevent the development of coronary heart disease risk factors, and to improve awareness and treatment of risk factors when then develop, is required to halt the epidemic of coronary heart disease that is occurring in Asia.

South Asian Ethnicity and Cardiovascular Risk

South Asians (SAs), in their countries or after migration, are at high risk of coronary artery disease (CAD) and mortality compared to other ethnic groups. It has been shown that >90% of CAD global risk could be attributed to 9 modifiable risk factors (RFs) worldwide. However, these conventional RFs may not fully explain this high risk of CAD among SAs. Therefore, attention has been directed toward nonconventional RFs. In this narrative review, we evaluate the conventional and emerging cardiovascular RFs characterizing SAs. These factors may explain the high morbidity and mortality among SAs. Further prospective studies are urgently needed to set algorithms for the optimal management of these RFs in high-risk populations like SAs.

Ethnic variation in the correlation between fasting glucose concentration and glycated hemoglobin (HbA1c)

OBJECTIVE

We aimed to determine the relationship between fasting serum glucose (FSG) concentration and glycated hemoglobin-A1c (HbA1c) in the 3 ethnicities in Singapore after adjustment for demographic and therapeutic variables.

METHODS

Fasting serum glucose (FSG), HbA1c, and serum creatinine levels were simultaneously sampled from 575 patients with diabetes (389 Chinese, 97 Indians, 89 Malays) in this cross-sectional study between January and May 2008, and the results were subjected to multivariate linear regression analysis.

RESULTS

We found a significant interaction between FSG and ethnicity on HbA1c. The correlation between FSG and HbA1c among Chinese subjects was 0.25 (95% confidence interval [CI]:0.2-0.3) relative to the Malays (0.38, 95% CI: 0.30-0.45) after adjustment for age; gender; serum creatinine concentrations; body mass index (BMI); duration of diabetes; use of sulfonylureas, metformin, and insulin; and hemoglobin (Hb) and red cell indices (P = .005). Hence, for a given FSG, the predicted HbA1c will be higher in Malays compared to Chinese subjects. We did not observe a statistically significant difference between Indians and Malays with respect to the correlation between FSG and HbA1c.

CONCLUSION

We showed a higher correlation between HbA1c and FSG in Malay subjects relative to the Chinese in this cohort. The ethnic variation in the HbA1c-FSG relationship may be related to differences in percentage contribution by the FSG to overall HbA1c among ethnic groups. Future studies using continuous glucose monitoring (CGM) to elucidate the relative contributions by FSG and postprandial glucose (PPG) to the daily blood glucose profile and the overall HbA1c by ethnicity are required.

Diabetes in South-East Asia: an update

According to the recent estimates by the International Diabetes Federation (IDF), South East-Asia (SEA) Region consisting of India, Sri Lanka, Bangladesh, Bhutan, Mauritius and Maldives, is home to more than 72 million adults with diabetes in 2013 and is expected to exceed 123 million in 2035. Nearly 95% of people with diabetes have type 2 diabetes (T2DM). Although type 1 diabetes (T1DM) is relatively rare in these countries, its prevalence is also rising. Furthermore, a large number (24.3 million) of people also have impaired glucose tolerance (IGT). Several characteristic differences are seen in the clinical and immunological presentation of these people when compared with their European counterparts. A sharp increase in the prevalence of T2DM has been observed in the SEA Region, both in urban and rural areas, which is mostly associated with the lifestyle transitions towards urbanisation and industrialisation. Evidence suggests that a large portion of T2DM may be preventable by lifestyle modification. However, morbidity and early mortality occur as a result of inadequate healthcare facilities for early detection and initiation of therapy, as well as suboptimal management of diabetes and associated morbidities. This is largely preventable by primary prevention of diabetes and enhancing awareness about the disease among the public and the healthcare providers. There is an urgent need for concerted efforts by government and non-governmental sectors to implement national programmes aimed at prevention, management and surveillance of the disease.

The architecture of risk for type 2 diabetes: understanding Asia in the context of global findings

The prevalence of Type 2 diabetes is rising rapidly in both developed and developing countries. Asia is developing as the epicentre of the escalating pandemic, reflecting rapid transitions in demography, migration, diet, and lifestyle patterns. The effective management of Type 2 diabetes in Asia may be complicated by differences in prevalence, risk factor profiles, genetic risk allele frequencies, and gene-environment interactions between different Asian countries, and between Asian and other continental populations. To reduce the worldwide burden of T2D, it will be important to understand the architecture of T2D susceptibility both within and between populations. This review will provide an overview of known genetic and nongenetic risk factors for T2D, placing the results from Asian studies in the context of broader global research. Given recent evidence from large-scale genetic studies of T2D, we place special emphasis on emerging knowledge about the genetic architecture of T2D and the potential contribution of genetic effects to population differences in risk.

Does ethnicity contribute to the control of cardiovascular risk factors among patients with type 2 diabetes?

This study aimed to examine the control of cardiovascular risk factors among the ethnic groups with type 2 diabetes in Malaysia. The authors analyzed the data of 70 092 adults from the Malaysian diabetes registry database. Malays had the worst achievement of target for most of the risk factors. Indians had poor achievement of control for waist circumference (odds ratio [OR] = 0.6, 95% confidence interval [CI] = 0.6-0.7) and high-density lipoprotein cholesterol (OR = 0.5, 95% CI = 0.4-0.5). As compared with the Malays, the Chinese had a better achievement of target control for the risk factors, including the following: body mass index (OR = 1.3, 95% CI = 1.2-1.4), blood pressure (OR = 1.3, 95% CI = 1.3-1.4), total cholesterol (OR = 1.7, 95% CI = 1.6-1.8), low-density lipoprotein cholesterol (OR = 1.7, 95% CI = 1.6-1.8), glycated hemoglobin A1c (OR = 1.4, 95% CI = 1.3-1.4) and fasting blood glucose (OR = 1.4, 95% CI = 1.3-1.5). Ethnicity, sociocultural factors, and psychobehavioral factors should be addressed in designing and management strategies for the control of cardiovascular risk factors among type 2 diabetes patients.

Visceral adipose tissue, but not waist circumference is a better measure of metabolic risk in Singaporean Chinese and Indian men

OBJECTIVES

Visceral adipose tissue (VAT) is an independent risk factor in cardiometabolic diseases and is commonly measured by computed tomography (CT). It is measured clinically by waist circumference (WC). The L4/5 intervertebral space VAT (L4/5 VAT) is traditionally used to represent total VAT volume. We set out to determine (1) the level of intervertebral space on CT that best approximates the total VAT volume; (2) compare the association between WC and VAT in Singaporean Chinese and Indian; and (3) examine the correlation between VAT and cardiometabolic risk factors.

SUBJECTS

A total of 60 Chinese and 60 Asian Indian men older than 60 years were recruited. Their medical history was taken and anthropometry was measured. Fasting glucose, insulin, lipids, adipokines and inflammatory markers were measured. Insulin resistance was evaluated by homeostasis model assessment-insulin resistance. VAT was determined by CT. Total VAT volume was calculated in 22 patients from VAT areas at seven intervertebral levels. The optimal VAT area most representative of total VAT volume was determined and used for all patients to approximate total VAT volume.

RESULTS

The VAT area at L2/3 intervertebral space (L2/3 VAT) correlated almost perfectly with VAT volume (R(2)=0.974 and 0.946 for Chinese and Indians, respectively). SUBJECTS from the two races had similar height, weight, body mass index (BMI), WC and L2/3 VAT but more Indian men had hypertension, hyperlipidemia and type 2 diabetes mellitus. WC was correlated with the L2/3 VAT area in both Chinese (r=0.484, P<0.001) and Indian subjects (r=0.366, P=0.004) without racial difference (P=0.2 for interaction term). L2/3 VAT also correlated better with cardiometabolic risk factors, adipokines and C-reactive protein than WC, BMI or L4/5 VAT.

CONCLUSION

The L2-L3 intervertebral space was the best anatomic level for a single-slice CT cross-sectional area measurement of VAT to approximate total body visceral adipose volume in this population of Chinese and Asian Indian men older than 60 years. L2/3 VAT was better correlated with multiple cardiovascular risk factors, adipokines and inflammatory marker than either L4/5 VAT, WC or BMI.

Health, lifestyle, belief and knowledge differences between two ethnic groups with specific reference to tobacco, diet and physical activity

AIMS

  To compare physical activity levels, body mass index, habitual diet, tobacco use and prevalence of non-communicable disease between the two ethnic groups and to identify predictors for differences between groups.

BACKGROUND

  Tobacco use, poor diet and physical inactivity are major lifestyle risk factors for chronic cardiovascular diseases, certain cancers, diabetes and chronic lung diseases. There are higher risk and incidence of these diseases in some ethnic groups, for example Asians have higher incidence of diabetes.

DESIGN

  Cross sectional survey.

METHODS

  Cross sectional survey of Asians of Indian descent and white British adults conducted between October-December 2009. Main outcome variables were lifestyle behaviours and BMI. Self-reported disease diagnosis was also collected. In a regression analysis, predictors of outcome variables were demographic variables and beliefs/attitudes/knowledge towards lifestyle behaviours.

RESULTS/FINDINGS

  Body mass index, tobacco use and non-communicable disease (except diabetes) were lower in Indians. Indians reported lower physical activity levels and greater salt use than Whites. Tobacco use was higher in Whites, but knowledge, attitudes and beliefs were similar between Whites and Indians.

CONCLUSION

  Health risk behaviour and morbidity are different between the two ethnic groups. Gender, age, educational level, beliefs, attitudes and knowledge do not explain these differences. Health promotion that aims to improve knowledge will probably not work and innovative methods are needed to improve health in high risk groups.

Prevalence, risk factors and complications associated with type 2 diabetes in migrant South Asians

It is estimated that type 2 diabetes (T2D) currently affects about 246 million people worldwide, with South Asians, especially Indians, having both the largest number of cases and the fastest growing prevalence. South Asian ethnicity has been identified as a major risk factor for the development of T2D with central adiposity, insulin resistance and an unfavourable lipid profile being identified as predominant signals of alarm. Leading databases, including Web of Science, Medline, PubMed and Science Direct, were consulted and manual searches were conducted for cited references in leading diabetes-related journals. In all, 152 articles were included for the final assessment reported in this review. Genetic predisposition, central adiposity and unfavourable lifestyle, including physical inactivity and an unhealthy diet, were associated with the prevalence of T2D in migrant South Asians. 'Westernization', acculturation, socio-economic factors and lack of knowledge about the disease have also been identified as contributors to the development of T2D in this population. Higher prevalence of T2D in migrant South Asians may not be entirely attributed to genetic predisposition; hence, ethnicity and associated modifiable risk factors need further investigation. Preventive measures and appropriate interventions are currently limited by the lack of ethnic-specific cut-off points for anthropometric and biological markers, as well as by the absence of reliable methods for dietary and physical activity assessment. This article describes the prevalence rate, risk factors and complications associated with T2D in migrant South Asians living in different countries.

Differential association of retinal arteriolar and venular caliber with diabetes and retinopathy

AIMS

To describe the relationship of retinal arteriolar and venular caliber with diabetes, retinopathy and hyperglycemia, in an Asian Indian population.

METHODS

This was a population-based cross-sectional study of 3400 (75.6% response rate) Singapore ethnic Indians aged 40-80 years. Central retinal arteriolar equivalent (CRAE) and central retinal venular equivalent (CRVE) were obtained using a validated computer-assisted program. Diabetes mellitus was identified using standardized criteria. Diabetic retinopathy was graded based on the modified Airlie House Classification System.

RESULTS

There were 980 (32.2%) participants with diabetes. Of these, 327 (33.4%) had diabetic retinopathy. After multivariate adjustment, diabetic persons had a wider CRAE (145.23μm vs 142.38μm, P<0.001). This relationship was stronger in persons without hyperlipidemia (P-interaction<0.1). Among diabetic participants, wider CRVE was related to increasing severity of retinopathy (P for trend<0.05) and this association may be altered by hypertensive status. Retinal arteriolar caliber widened with increasing glucose (P<0.001) and HbA1C (P<0.001) levels.

CONCLUSIONS

In Indian adults, wider retinal arteriolar caliber is associated with diabetes and hyperglycemia, while wider retinal venular caliber is associated with diabetic retinopathy. This is consistent with white populations and confirms the differential systemic association of retinal vascular caliber in Asian Indians.

Percutaneous coronary intervention in Asians--are there differences in clinical outcome?

Background

Ethnic differences in clinical outcome after percutaneous coronary intervention (PCI) have been reported. Data within different Asian subpopulations is scarce. We aim to explore the differences in clinical profile and outcome between Chinese, Malay and Indian Asian patients who undergo PCI for coronary artery disease (CAD).

Methods

A prospective registry of consecutive patients undergoing PCI from January 2002 to December 2007 at a tertiary care center was analyzed. Primary endpoint was major adverse cardiovascular events (MACE) of myocardial infarction (MI), repeat revascularization and all-cause death at six months.

Results

7889 patients underwent PCI; 7544 (96%) patients completed follow-up and were included in the analysis (79% males with mean age of 59 years ± 11). There were 5130 (68%) Chinese, 1056 (14%) Malays and 1001 (13.3%) Indian patients. The remaining 357 (4.7%) patients from other minority ethnic groups were excluded from the analysis. The primary end-point occurred in 684 (9.1%) patients at six months. Indians had the highest rates of six month MACE compared to Chinese and Malays (Indians 12% vs. Chinese 8.2% vs. Malays 10.7%; OR 1.55 95%CI 1.24-1.93, p < 0.001). This was contributed by increased rates of MI (Indians 1.9% vs. Chinese 0.9% vs. Malays 1.3%; OR 4.49 95%CI 1.91-10.56 p = 0.001), repeat revascularization (Indians 6.5% vs. Chinese 4.1% vs. Malays 5.1%; OR 1.64 95%CI 1.22-2.21 p = 0.0012) and death (Indians 11.4% vs. Chinese 7.6% vs. Malays 9.9%; OR 1.65 95%CI 1.23-2.20 p = 0.001) amongst Indian patients.

Conclusion

These data indicate that ethnic variations in clinical outcome exist following PCI. In particular, Indian patients have higher six month event rates compared to Chinese and Malays. Future studies are warranted to elucidate the underlying mechanisms behind these variations.

Salt sensitivity, insulin resistance, and public health in India

OBJECTIVE

To provide a current overview of the worldwide prevalence and pattern of cardiovascular disease and discuss the role of sodium intake and salt sensitivity, with a focus on the Asian Indian population.

METHODS

An extensive search of the literature from PubMed and the Cochrane Library was undertaken. Moreover, the pathophysiologic basis of the relationship between sodium intake and insulin sensitivity in various populations was reviewed.

RESULTS

High blood pressure is the most common cause of cardiovascular disease and mortality globally. Although salt sensitivity is a frequent determinant of hypertension, a strong link between salt sensitivity and cardiovascular disease associated with insulin resistance has not received adequate attention. This may be particularly relevant to the public health challenges of increasing prevalences of obesity, diabetes, and cardiometabolic syndrome in India where, according to recent estimates, approximately 60% of the world's cases of cardiovascular disease occur and the salt consumption is among the highest in any large population.

CONCLUSION

There is evidence for a strong link between increased salt sensitivity and insulin resistance leading to metabolic syndrome and cardiovascular disease. This relationship may be particularly relevant to the escalating epidemic of cardiovascular disease in the southern Asian Indian population. A broad-based community action to achieve at least a modest restriction of salt intake can yield important health benefits and is urgently needed.

Heterogeneity of diabetes outcomes among asians and pacific islanders in the US: the diabetes study of northern california (DISTANCE)

OBJECTIVE

Ethnic minorities with diabetes typically have lower rates of cardiovascular outcomes and higher rates of end-stage renal disease (ESRD) compared with whites. Diabetes outcomes among Asian and Pacific Islander subgroups have not been disaggregated.

RESEARCH DESIGN AND METHODS

We performed a prospective cohort study (1996-2006) of patients enrolled in the Kaiser Permanente Northern California Diabetes Registry. There were 64,211 diabetic patients, including whites (n = 40,286), blacks (n = 8,668), Latinos (n = 7,763), Filipinos (n = 3,572), Chinese (n = 1,823), Japanese (n = 951), Pacific Islanders (n = 593), and South Asians (n = 555), enrolled in the registry. We calculated incidence rates (means ± SD; 7.2 ± 3.3 years follow-up) and created Cox proportional hazards models adjusted for age, educational attainment, English proficiency, neighborhood deprivation, BMI, smoking, alcohol use, exercise, medication adherence, type and duration of diabetes, HbA(1c), hypertension, estimated glomerular filtration rate, albuminuria, and LDL cholesterol. Incidence of myocardial infarction (MI), congestive heart failure, stroke, ESRD, and lower-extremity amputation (LEA) were age and sex adjusted.

RESULTS

Pacific Islander women had the highest incidence of MI, whereas other ethnicities had significantly lower rates of MI than whites. Most nonwhite groups had higher rates of ESRD than whites. Asians had ~60% lower incidence of LEA compared with whites, African Americans, or Pacific Islanders. Incidence rates in Chinese, Japanese, and Filipinos were similar for most complications. For the three macrovascular complications, Pacific Islanders and South Asians had rates similar to whites.

CONCLUSIONS

Incidence of complications varied dramatically among the Asian subgroups and highlights the value of a more nuanced ethnic stratification for public health surveillance and etiologic research.

Insulin resistance is associated with a metabolic profile of altered protein metabolism in Chinese and Asian-Indian men

AIMS/HYPOTHESIS

Insulin resistance (IR) is associated with obesity, but can also develop in individuals with normal body weight. We employed comprehensive profiling methods to identify metabolic events associated with IR, while controlling for obesity.

METHODS

We selected 263 non-obese (BMI approximately 24 kg/m2) Asian-Indian and Chinese men from a large cross-sectional study carried out in Singapore. Individuals taking medication for diabetes or hyperlipidaemia were excluded. Participants were separated into lower and upper tertiles of IR based on HOMA indices of < or =1.06 or > or =1.93, respectively. MS-based metabolic profiling of acylcarnitines, amino acids and organic acids was combined with hormonal and cytokine profiling in all participants.

RESULTS

After controlling for BMI, commonly accepted risk factors for IR, including circulating fatty acids and inflammatory cytokines, did not discriminate the upper and lower quartiles of insulin sensitivity in either Asian- Indian or Chinese men. Instead, IR was correlated with increased levels of alanine, proline, valine, leucine/isoleucine, phenylalanine, tyrosine, glutamate/glutamine and ornithine, and a cluster of branched-chain and related amino acids identified by principal components analysis. These changes were not due to increased protein intake by individuals in the upper quartile of IR. Increased abdominal adiposity and leptin, and decreased adiponectin and IGF-binding protein 1 were also correlated with IR.

CONCLUSIONS/INTERPRETATION

These findings demonstrate that perturbations in amino acid homeostasis, but not inflammatory markers or NEFAs, are associated with IR in individuals of relatively low body mass.

C-reactive protein and retinal microvascular caliber in a multiethnic asian population

Retinal microvascular caliber is a risk marker for cardiovascular disease. The authors examined the relation between high-sensitivity C-reactive protein (hsCRP) and retinal microvascular caliber in a multiethnic Asian population (n = 3,583) of Chinese, Malays, and Indians aged 24-95 years residing in Singapore (2003-2007). Retinal arteriolar and venular diameters were measured and summarized as central retinal arteriolar equivalent (CRAE) and central retinal venular equivalent (CRVE), respectively. Persons with higher levels of hsCRP had wider CRVE (P(trend) < 0.001). In subgroup analysis stratified for different cardiovascular disease risk factors, the association between hsCRP and CRVE was seen in persons without diabetes (P(trend) < 0.001) but was absent in persons with diabetes (P(trend) = 0.200; P(interaction) = 0.004). No significant interaction between race/ethnicity and hsCRP in relation to retinal vascular caliber was observed. These data suggest that retinal venular caliber is associated with higher levels of hsCRP in Asians, which is consistent with studies in white Caucasian populations, further supporting the concept that retinal venular caliber may be a marker for low-grade systemic inflammation.

Ethnic difference in patients with type 2 diabetes mellitus in inter-East Asian populations: a systematic review and meta-analysis focusing on gene polymorphism

BACKGROUND

We previously reported that the fasting serum insulin level was significantly lower in Japanese patients than in Korean and Chinese patients, and showed evidence that a difference in the dietary component would be one of the most influential factors for the ethnic difference. However, it is well known that type 2 diabetes mellitus (T2DM) results from the interaction between genetic predispositions and environmental risk factors. Therefore, we investigated ethnic differences by focusing on gene polymorphism, possibly related to T2DM in Japanese, Korean, and Chinese subjects.

METHODS

Data sources included MEDLINE and EMBASE between January 2001 and October 2008. We conducted a search for articles containing minor allele frequency (MAF) in the gene polymorphisms of peroxisome proliferator-activated receptor-γ (PPARG), inward-rectifying potassium channel Kir6.2 (KCNJ11), Calpain 10 (CAPN10), and transcription factor 7-like 2 (TCF7L2). The pooled odds ratio was calculated by using a fixed-effects model with the Mantel-Haenszel method after confirming statistical evidence of homogeneity across the ethnicities using the Breslow-Day test.

RESULTS

The Breslow-Day test revealed that there were no statistically significant differences between ethnicities in pooled odds ratios for the gene polymorphisms in PPARG (P = 0.828), KCNJ11 (P = 0.194), CAPN10 (P = 0.090), and TCF7L2 (P = 0.376). Also, pooled odds ratios of each gene polymorphism in East Asians were 0.645 for PPARG (P = 0.000), 1.168 for KCNJ11 (P = 0.000), 0.967 for CAPN10 (P = 0.759), and 1.386 for TCF7L2 (P = 0.000).

CONCLUSION

The results of this study and our previous studies suggest that behavioral and environmental risk factors have a more significant impact on ethnic difference in East Asian patients with T2DM compared with genetic predispositions.

Ethnic difference in inter-East Asian subjects with normal glucose tolerance and impaired glucose regulation: a systematic review and meta-analysis focusing on fasting serum insulin

AIMS

To investigate ethnic difference by focusing on fasting serum insulin (FSI) in inter-East Asian subjects with normal glucose tolerance (NGT) and impaired glucose regulation (IGR).

METHODS

Data sources included MEDLINE and EMBASE between 2001 and 2007. We conducted a search for articles containing mean or geometric mean values of FSI in East Asian subjects with NGT, IGR, or type 2 diabetes (T2DM). The Monte Carlo method was used for simulation of the mean and standard deviation of individual measures in each ethnic group; calculation of the median ratio and 95% confidence interval of individual measures between ethnic groups.

RESULTS

Twenty-two articles fully met our pre-determined criteria and were included in the meta-analysis. Results of the meta-analysis revealed that FSI level is significantly lower in Japanese subjects with NGT, IGR, or T2DM than in Korean and Chinese subjects.

CONCLUSIONS

Ethnic difference in FSI level between East Asians was observed in not only T2DM patients but also subjects with NGT or IGR. The lower FSI level in Japanese subjects was accompanied by lower triglyceride level. These results suggest that ethnic difference in dietary habit was one of the most influential factors for the ethnic difference in FSI.

Ethnic difference in patients with type 2 diabetes mellitus in inter-East Asian populations: a systematic review and meta-analysis focusing on fasting serum insulin

AIMS

To investigate ethnic difference by focusing on fasting serum insulin (FSI) in inter-East Asian patients with type 2 diabetes.

METHODS

Data sources included MEDLINE and EMBASE between 2001 and 2006. We conducted a search for articles containing mean or geometric mean values of FSI in East Asian patients with type 2 diabetes. The Monte Carlo method was used for simulation of the mean and standard deviation of individual measures in each ethnic group; calculation of the median ratio and 95% confidence interval of individual measures between ethnic groups.

RESULTS

The initial search identified a total of 996 journal articles. After reviewing the titles and abstracts of these articles, 201 studies were selected for further screening and the complete papers on these studies were then reviewed in detail. Of these, seven articles fully met our pre-determined criteria and were included in the meta-analysis. Results of the meta-analysis revealed that FSI level is significantly lower in Japanese patients than in Korean and Chinese patients.

CONCLUSIONS

Results from our review of ethnic differences in dietary habit in the inter-East Asian population suggested that difference in dietary component was one of the most influential factors for the ethnic difference.