Comparison of case fatality in south Asian and white patients after acute myocardial infarction: observational study

Life expectancy following a cardiovascular event in individuals with and without type 2 diabetes: A UK multi-ethnic population-based observational study

BACKGROUND AND AIMS

We aimed to evaluate the life expectancy following the first cardiovascular disease (CVD) event by type 2 diabetes (T2D) status and ethnicity.

METHODS AND RESULTS

We used the Clinical Practice Research Datalink database in England (UK), linked to the Hospital Episode Statistics information, to identify individuals with and without T2D who survived a first CVD event between 1st Jan 2007 and 31st Dec 2017; subsequent death events were extracted from the Office for National Statistics database. Ethnicity was categorised as White, South Asian (SA), Black, or other. Flexible parametric survival models were used to estimate survival and predict life expectancy. 59,939 individuals with first CVD event were included: 7596 (12.7%) with T2D (60.9% men; mean age at event: 69.7 years [63.2 years in SA, 65.9 in Black, 70.2 in White]) and 52,343 without T2D (56.7% men; 65.9 years [54.7 in Black, 58.2 in SA, 66.3 in White]). Accounting for potential confounders (sex, deprivation, lipid-lowering medication, current smoking, and pre-existing hypertension), comparing individuals with vs without T2D the mortality rate was 53% higher in White (hazard ratio [HR]: 1.53 [95% CI: 1.44, 1.62]), corresponding to a potential loss of 3.87 (3.30, 4.44) life years at the age of 50 years in individuals with T2D. No evidence of a difference in life expectancy was observed in individuals of SA (HR: 0.82 [0.52, 1.29]; -1.36 [-4.58, 1.86] life years), Black (HR: 1.26 [0.59, 2.70]; 1.21 [-2.99, 5.41] life years); and other (HR: 1.64 [0.80, 3.39]; 3.89 [-2.28, 9.99] life years) ethnic group.

CONCLUSION

Following a CVD event, T2D is associated with a different prognosis and life years lost among ethnic groups.

Heightened risks of cardiovascular disease in South Asian populations: causes and consequences

INTRODUCTION

South Asian individuals comprise almost a quarter of the world's population and have an excess risk of atherosclerotic cardiovascular disease (ASCVD) compared to other ethnicities. In part, this can be explained by higher prevalence, earlier onset, and suboptimal control of traditional cardiovascular risk factors, such as insulin resistance, metabolic syndrome, and dyslipidaemia. However, there remains a significant residual excess risk associated with South Asian ethnicity after controlling for traditional risk factors.

AREAS COVERED

In this review, we describe the epidemiology of ASCVD in both native and diaspora South Asian populations. We explore how traditional cardiovascular risk factors, novel cardiovascular risk factors, and social determinants of health may contribute to the excess ASCVD risk seen in South Asian populations.

EXPERT OPINION

There should be increased awareness of the relative importance of South Asian ethnicity and related social determinants of health, as risk factors for ASCVD. Systematic screening processes should be tailored to this population, and modifiable risk factors should be treated aggressively. Further research is required to quantify determinants of the excess ASCVD risk seen in South Asian populations and to develop targeted interventions to address these factors.

Ethnic differences between South Asians and White Caucasians in cardiovascular disease-related mortality in developed countries: a systematic literature review

BACKGROUND

Cardiovascular disease is the leading cause of death worldwide, with significantly worse mortality-related outcomes in ethnic minorities in developed countries. A systematic literature review and meta-analysis of observational studies was conducted to investigate cardiovascular disease-related mortality inequalities between South Asian and White Caucasian ethnic groups.

METHODS

Published studies on mortality between South Asians and Whites in developed countries were retrieved from MEDLINE, PubMed, Embase, Web of Science, and grey literature sources (inception-April 2021) and critically appraised using the Quality in Prognosis Studies tool. Bayesian random-effects meta-analyses were performed for both primary and secondary outcomes. Heterogeneity was determined using the I² statistic.

RESULTS

Of the 9879 studies screened originally, 41 were deemed eligible. A further 3 studies were included via the later search. Of these, 15 reported cardiovascular disease-related mortality, 23 reported all-cause mortality, and 6 reported both. The meta-analysis results showed that South Asians had a significantly increased risk of cardiovascular disease mortality compared to Whites (risk ratio = 1.32; 95% credible interval = 1.14 to 1.54) and a decreased risk of all-cause mortality (risk ratio = 0.95; 95% credible interval = 0.83 to 1.12).

DISCUSSION

South Asians had statistically significantly higher odds of cardiovascular disease-related mortality compared to Whites, but not for all-cause mortality. Risk of bias was a serious concern mainly due to a lack of confounders being reported.

SYSTEMATIC REVIEW REGISTRATION

PROSPERO: CRD42021240865.

Ethnicity and prognosis following a cardiovascular event in people with and without type 2 diabetes: Observational analysis in over 5 million subjects in England

AIMS

To quantify ethnic differences in the risk of all-cause mortality and cardiovascular disease (CVD) events following a first CVD event in people with and without type 2 diabetes.

METHODS

We identified 5,349,271 subjects with a first CVD between 1 January 2002 and 31 May 2020 in England; CVD included aortic aneurism, cerebrovascular accident, heart failure, myocardial infarction, peripheral vascular disease, and other cardiovascular diseases. We estimated adjusted hazard ratios (HRs) for type 2 diabetes and ethnicity of three outcomes: fatal and nonfatal second CVD event (different phenotype compared to the first) and all-cause mortality.

RESULTS

Relative to White, HRs indicated lower rates in all ethnicities and for all outcomes in both men (from 0.64 to 0.79 for all-cause death; 0.78-0.79 for CVD-related death; and 0.85-0.98 for a second CVD event) and women (0.69-0.77; 0.77-0.83; 0.83-0.95, respectively). Irrespective of ethnicity and sex, type 2 diabetes increased rates of all outcomes by around a third.

CONCLUSIONS

Prognosis following a CVD event was consistently worse in subjects with type 2 diabetes while varied across ethnicities, suggesting the implementation of different strategies for the secondary prevention of CVD in different ethnic groups.

Socioeconomic Determinants of Cardiovascular Diseases, Obesity, and Diabetes among Migrants in the United Kingdom: A Systematic Review

There has been little agreement on the role that socioeconomic factors play in the aetiology of cardiovascular diseases (CVDs), obesity, and diabetes among migrants in the United Kingdom (UK). We systematically reviewed the existing evidence on this association to contribute to filling this gap in the literature. Two reviewers were involved at each stage of the review process to ensure validity. We comprehensively searched through several electronic databases and grey literature sources to identify potentially eligible papers for our review. We extracted data from our finally included studies and appraised the methodological rigour of our studies. A narrative synthesis approach was used to synthesise and interpret the extracted data. We sieved through 2485 records identified from our search and finally obtained 10 studies that met our inclusion criteria. The findings of this review show that there is a trend towards an association between socioeconomic factors and CVDs, diabetes, and obesity among migrants in the UK. However, the picture was more complex when specific socioeconomic variables and migrant subgroups were analysed. The evidence for this association is inconclusive and its causal relationship remains speculative. There is, therefore, the need for further research to understand the exact association between socioeconomic factors and CVD, diabetes, and obesity among migrants in the UK.

Causal Association Between Birth Weight and Adult Diseases: Evidence From a Mendelian Randomization Analysis

Purpose: Birth weight has a profound long-term impact on individual’s predisposition to various diseases at adulthood—a hypothesis commonly referred to as the fetal origins of adult diseases. However, it is not fully clear to what extent the fetal origins of adult diseases hypothesis holds and it is also not completely known what types of adult diseases are causally affected by birth weight.

Materials and methods: Mendelian randomization using multiple genetic instruments associated with birth weight was performed to explore the causal relationship between birth weight and adult diseases. The causal relationship between birth weight and 21 adult diseases as well as 38 other complex traits was examined based on data collected from 37 large-scale genome-wide association studies with up to 340,000 individuals of European ancestry. Causal effects of birth weight were estimated using inverse-variance weighted methods. The identified causal relationships between birth weight and adult diseases were further validated through extensive sensitivity analyses, bias calculation, and simulations.

Results: Among the 21 adult diseases, three were identified to be inversely causally affected by birth weight after the Bonferroni correction. The measurement unit of birth weight was defined as its standard deviation (i.e., 488 g), and one unit lower birth weight was causally related to an increased risk of coronary artery disease (CAD), myocardial infarction (MI), type 2 diabetes (T2D), and BMI-adjusted T2D, with the estimated odds ratios of 1.34 [95% confidence interval (CI) 1.17–1.53], 1.30 (95% CI 1.13–1.51), 1.41 (95% CI 1.15–1.73), and 1.54 (95% CI 1.25–1.89), respectively. All these identified causal associations were robust across various sensitivity analyses that guard against various confounding due to pleiotropy or maternal effects as well as reverse causation. In addition, analysis on 38 additional complex traits did not identify candidate traits that may mediate the causal association between birth weight and CAD/MI/T2D.

Conclusions: The results suggest that lower birth weight is causally associated with an increased risk of CAD, MI, and T2D in later life, supporting the fetal origins of adult diseases hypothesis.

Racial/ethnic disparities among Asian Americans in inpatient acute myocardial infarction mortality in the United States

Background

Acute myocardial infarction (AMI) is a common high-risk disease with inpatient mortality of 5% nationally. But little is known about this outcome among Asian Americans (Asians), a fast growing racial/ethnic minority in the country. The objectives of the study are to obtain near-national estimates of differences in AMI inpatient mortality between minorities (including Asians) and non-Hispanic Whites and identify comorbidities and sociodemographic characteristics associated with these differences.

Method

This is a retrospective analysis of 2010–2011 state inpatient discharge data from 10 states with the largest share of Asian population. We identified hospitalization with a primary diagnosis of AMI using the ICD-9 code and used self-reported race/ethnicity to identify White, Black, Hispanic, and Asian. We performed descriptive analysis of sociodemographic characteristics, medical comorbidities, type of AMI, and receipt of cardiac procedures. Next, we examined overall inpatient AMI mortality rate based on patients’ race/ethnicity. We also examined the types of AMI and a receipt of invasive cardiac procedures by race/ethnicity. Lastly, we used sequential multivariate logistic regression models to study inpatient mortality for each minority group compared to Whites, adjusting for covariates.

Results

Over 70% of the national Asian population resides in the 10 states. There were 496,472 hospitalizations with a primary diagnosis of AMI; 75% of all cases were Whites, 10% were Blacks, 12% were Hispanics, and 3% were Asians. Asians had a higher prevalence of cardiac comorbidities, including hypertension, diabetes, and kidney failure compared to Whites (p-value< 0.01). There were 158,623 STEMI (ST-elevation AMI), and the proportion of hospitalizations for STEMI was the highest for Asians (35.2% for Asians, 32.7% for Whites, 25.3% for Blacks, and 32.1% for Hispanics). Asians had the highest rates of inpatient AMI mortality: 7.2% for Asians, 6.3% for Whites, 5.4% for Blacks, and 5.9% for Hispanics (ANOVA p-value < 0.01). In adjusted analyses, Asians (OR = 1.11 [95% CI: 1.04–1.19]) and Hispanics (OR = 1.14 [1.09–1.19]) had a higher likelihood of inpatient mortality compared to Whites.

Conclusions

Asians had a higher risk-adjusted likelihood of inpatient AMI mortality compared to Whites. Further research is needed to identify the underlying reasons for this finding to improve AMI disparities for Asians.

Clinical outcomes following primary percutaneous coronary intervention for ST-elevation myocardial infarction according to sex and race

Background:

Female sex and South Asian race have been associated with poor clinical outcomes following primary percutaneous coronary intervention (PPCI) for ST-segment elevation myocardial infarction (STEMI) but remain understudied in large real-world series. We therefore investigated the association of sex and race with clinical outcomes following PPCI.

Methods:

We conducted a prospective study of all patients undergoing PPCI for STEMI between January 2009 and December 2011 at a large UK cardiac centre. Clinical characteristics and outcomes were compared according to sex and race using Chi-square test, independent samples Student’s t-test and Mann–Whitney U-test. Primary and secondary outcomes were 12-month major adverse cardiovascular events (MACEs) – defined as all-cause mortality, myocardial infarction and unplanned revascularization, analysed using Cox proportional hazard models adjusting for cardiovascular risk factors.

Results:

Three thousand and forty-nine patients were included. Women ( n=826) were older than men ( n=2223) (median age 69 vs. 60 years, p <0.01). Mortality (hazard ratio 1.48 (1.15–1.90)) and MACE (hazard ratio 1.40 (1.14–1.72)) were higher in women in univariable analysis. However, there were no significant sex-differences in mortality or MACE after age-stratification alone. Multivariable analysis also showed no significant differences in outcomes between sexes. South Asians ( n=297) were younger but had a higher prevalence of most risk factors than White patients ( n=2570). Mortality and MACE did not differ significantly between South Asian and White patients in univariable or multivariable analysis.

Conclusion:

MACE and mortality was not greater in women, or in South Asian patients following PPCI after adjustment for cardiovascular risk factors including age, which was most strongly associated with both outcomes.

Using nationwide ‘big data’ from linked electronic health records to help improve outcomes in cardiovascular diseases: 33 studies using methods from epidemiology, informatics, economics and social science in the ClinicAl disease research using LInked Bespoke studies and Electronic health Records (CALIBER) programme

Background

Electronic health records (EHRs), when linked across primary and secondary care and curated for research use, have the potential to improve our understanding of care quality and outcomes.

Objective

To evaluate new opportunities arising from linked EHRs for improving quality of care and outcomes for patients at risk of or with coronary disease across the patient journey.

Design

Epidemiological cohort, health informatics, health economics and ethnographic approaches were used.

Setting

230 NHS hospitals and 226 general practices in England and Wales.

Participants

Up to 2 million initially healthy adults, 100,000 people with stable coronary artery disease (SCAD) and up to 300,000 patients with acute coronary syndrome.

Main outcome measures

Quality of care, fatal and non-fatal cardiovascular disease (CVD) events.

Data platform and methods

We created a novel research platform [ClinicAl disease research using LInked Bespoke studies and Electronic health Records (CALIBER)] based on linkage of four major sources of EHR data in primary care and national registries. We carried out 33 complementary studies within the CALIBER framework. We developed a web-based clinical decision support system (CDSS) in hospital chest pain clinics. We established a novel consented prognostic clinical cohort of SCAD patients.

Results

CALIBER was successfully established as a valid research platform based on linked EHR data in nearly 2 million adults with > 600 EHR phenotypes implemented on the web portal (seehttps://caliberresearch.org/portal). Despite national guidance, key opportunities for investigation and treatment were missed across the patient journey, resulting in a worse prognosis for patients in the UK compared with patients in health systems in other countries. Our novel, contemporary, high-resolution studies showed heterogeneous associations for CVD risk factors across CVDs. The CDSS did not alter the decision-making behaviour of clinicians in chest pain clinics. Prognostic models using real-world data validly discriminated risk of death and events, and were used in cost-effectiveness decision models.

Conclusions

Emerging ‘big data’ opportunities arising from the linkage of records at different stages of a patient’s journey are vital to the generation of actionable insights into the diagnosis, risk stratification and cost-effective treatment of people at risk of, or with, CVD.

Future work

The vast majority of NHS data remain inaccessible to research and this hampers efforts to improve efficiency and quality of care and to drive innovation. We propose three priority directions for further research. First, there is an urgent need to ‘unlock’ more detailed data within hospitals for the scale of the UK’s 65 million population. Second, there is a need for scaled approaches to using EHRs to design and carry out trials, and interpret the implementation of trial results. Third, large-scale, disease agnostic genetic and biological collections linked to such EHRs are required in order to deliver precision medicine and to innovate discovery.

Study registration

CALIBER studies are registered as follows: study 2 – NCT01569139, study 4 – NCT02176174 and NCT01164371, study 5 – NCT01163513, studies 6 and 7 – NCT01804439, study 8 – NCT02285322, and studies 26–29 – NCT01162187. Optimising the Management of Angina is registered as Current Controlled Trials ISRCTN54381840.

Funding

The National Institute for Health Research (NIHR) Programme Grants for Applied Research programme (RP-PG-0407-10314) (all 33 studies) and additional funding from the Wellcome Trust (study 1), Medical Research Council Partnership grant (study 3), Servier (study 16), NIHR Research Methods Fellowship funding (study 19) and NIHR Research for Patient Benefit (study 33).

The Experiences and Needs of Gujarati Hindu Patients and Partners in the First Month after a Myocardial Infarction

BACKGROUND

South Asian people living in the United Kingdom are at increased risk of coronary heart disease, have higher mortality rates and are less likely to be treated when compared to the white population. There is, however, little information about the experiences and needs of this group after discharge from hospital.

AIMS

To explore the experiences and needs of Gujarati Hindu patients and their partners in the first month after a myocardial infarction.

METHODS

Using a qualitative research approach, semi-structured interviews were conducted by a Gujarati-speaking researcher with 35 patients and their partners at home during early convalescence.

RESULTS

A number of categories emerged from the data which pertained to a lack of information and advice, poor performance of activity, little lifestyle adjustment, poor expectations, lack of future plans, strong family support, dissatisfaction with the family doctor, and a significant belief in fate.

CONCLUSION

Experiences and health care needs of Gujarati Hindu patients with myocardial infarction appear different to those of non-Asians. Cardiac aftercare and rehabilitation services should take account of such information

Insulin resistance syndrome in South Asians

Although South Asians express increased features (conventional) of insulin resistance syndrome, these do not fully explain the increased mortality both from ischaemic heart disease and ischaemic stroke in South Asians compared to Whites. Thrombotic risk factors for vascular disease, as a part of insulin resistance syndrome in South Asians, are being investigated and are an important moiety. The management of the epidemic of ischaemic vascular disease in South Asians is a major global endeavour.

Review: Diabetes and cardiac disease in South Asians

South Asians have a higher prevalence of diabetes, coronary heart disease and cardiovascular death. Their predisposition to insulin resistance partly explains this excess risk. After immigration, the adoption of a western diet allied to increased sedentary behaviour leads to weight gain, hypertension and hyperlipidaemia, factors which in turn combine to amplify the chances of getting heart disease. Further contributory factors are increased sub-clinical inflammation, increased thrombogenic tendency and higher serum homocysteine levels. South Asians with diabetes might do as well as White people with respect to intensive glycaemic and blood pressure control. However, there is little evidence for measures to reduce cardiovascular risk as South Asians have not been included as a subgroup in most large trials. Future prospective studies, including studies on the prevention of diabetes and cardiovascular disease in this high-risk population, are therefore urgently required.

Exploration of the psychological impact and adaptation to cardiac events in South Asians in the UK: a qualitative study

OBJECTIVE

There is little research on how different ethnic groups adapt after an acute cardiac event. This qualitative study explores between-ethnicity and within-ethnicity variation in adaptation, and the psychological impact of an acute cardiac event among UK South Asian and white British people.

SETTING

We purposively sampled people by ethnic group from general practices in London who had a new myocardial infarction, angina or acute arrhythmia in the preceding 18 months.

PARTICIPANTS

We conducted 28 semistructured interviews for exploring the psychological symptoms, experiences and adaptations following a cardiac event among South Asians (Indian and Bangladeshi) in comparison to white British people. Data were analysed using a thematic 'framework' approach.

RESULTS

Findings showed heterogeneity in experiences of the cardiac event and its subsequent psychological and physical impact. Adaptation to the event related predominantly to life circumstances, personal attitudes and employment status. Anxiety and low mood symptoms were common sequelae, especially in the Bangladeshi group. Indian men tended to normalise symptoms and the cardiac event, and reported less negative mood symptoms than other groups. Fear of physical exertion, particularly heavy lifting, persisted across the groups. Some people across all ethnic groups indicated the need for more psychological therapy postcardiac event. Socioeconomic circumstances, age and prior work status appeared to be more important in relation to adaptation after a cardiac event than ethnic status.

CONCLUSIONS

Heterogeneity in views and experiences related to the socioeconomic background, age and work status of the participants along with some cultural influences. Rehabilitation programmes should be flexibly tailored for individuals in particular and where relevant, specific support should be provided for returning to work.

Using an interactive DVD about type 2 diabetes and insulin therapy in a UK South Asian community and in patient education and healthcare provider training

OBJECTIVES

To develop and pilot-test the feasibility and effectiveness of an interactive DVD about misconceptions within South Asian communities regarding insulin treatment in type 2 diabetes, for educating patients and community members and training healthcare providers.

METHODS

The project setting was a South Asian (mainly Indian) community in Leicester, UK. Qualitative evidence from our previous studies was used to inform the content of the DVD script and accompanying resources. The intervention involved three components: facilitating DVD viewings for people with/without diabetes in community settings; training healthcare providers involved in managing South Asian patients with diabetes in primary care; and using the DVD and resources in primary care patient consultations. Evaluation involved a range of approaches including face-to-face interviews, telephone feedback and questionnaires.

RESULTS

Analysis of questionnaires and qualitative feedback from community participants showed some significant changes in attitudes and understanding about insulin and high acceptability of the DVD. Healthcare providers who attended the training found it informative and perceived the DVD and visual resources as potentially useful for facilitating acceptance of insulin. Primary care patient recruitment was challenging, but participants described the DVD as an acceptable and informative way of learning about insulin therapy.

CONCLUSION

The DVD intervention was effective and feasible at community and healthcare provider levels.

PRACTICE IMPLICATIONS

Although based on a small sample, at patient level our findings suggested that the DVD worked at different levels helping some to accept the need for insulin and others to consolidate a decision to commence this treatment. Consideration needs to be given to patient engagement strategies for implementation in primary care consultations.

Cardiovascular disease incidence and survival: Are migrants always worse off?

Studies on cardiovascular disease (CVD) incidence and survival show varying results between different ethnic groups. Our aim was to add a new dimension by exploring the role of migrant status in combination with ethnic background on incidence of-and survival from-CVD and more specifically acute myocardial infarction (AMI) and stroke. We conducted a historically prospective cohort study comprising all newly-arrived migrants to Denmark between 1.1.1993 and 31.12.2010 (n = 114,331), matched 1:6 to Danish-born by age and sex. CVD incidence was retrieved from the National Patient Registry and differences in incidence were assessed by Poisson regression and stratified by sex. Survival differences were assessed by Cox regression using all-cause and cause-specific mortality as outcome. Male refugees had significantly lower incidence of CVD (RR = 0.89; 95 % CI 0.85-0.93) and stroke (IRR = 0.62; 95 % CI 0.56-0.69) compared to Danish-born, but significantly higher incidence of AMI (IRR = 1.12; 95 % CI 1.02-1.24). Female refugees had similar rates of CVD and AMI, but significantly lower incidence of stroke (RR = 0.76; 95 % CI 0.67-0.85). Both male and female family-reunified immigrants had significantly lower incidence of CVD, AMI and stroke. All-cause and cause-specific survival after CVD, AMI and stroke was similar or significantly better for migrants compared to Danish-born, regardless of type of migrant (refugee vs. family-reunified) or country of origin. Refugees are disadvantaged in terms of some types of cardiovascular disease compared to Danish-born. Family-reunified migrants on the other hand had lower rates of CVD. All migrants had better survival than Danish-born indicating that migrants may not always be disadvantaged in health.

A cross-sectional study of the prevalence and correlates of tobacco use in Chennai, Delhi, and Karachi: data from the CARRS study

Background

Tobacco burdens in India and Pakistan require continued efforts to quantify tobacco use and its impacts. We examined the prevalence and sociodemographic and health-related correlates of tobacco use in Delhi, Chennai (India), and Karachi (Pakistan).

Methods

Analysis of representative surveys of 11,260 participants (selected through multistage cluster random sampling; stratified by gender and age) in 2011 measured socio-demographics, tobacco use history, comorbid health conditions, and salivary cotinine. We used bivariate and multivariate regression analyses to examine factors associated with tobacco use.

Results

Overall, 51.8 % were females, and 61.6 % were below the age of 45 years. Lifetime (ever) tobacco use prevalence (standardized for world population) was 45.0 %, 41.3 %, and 42.5 % among males, and 7.6 %, 8.5 %, and 19.7 % among females in Chennai, Delhi, and Karachi, respectively. Past 6 month tobacco use prevalence (standardized for world population) was 38.6 %, 36.1 %, and 39.1 % among males, and 7.3 %, 7.1 %, and 18.6 % among females in Chennai, Delhi, and Karachi, respectively. In multivariable regression analyses, residing in Delhi or Karachi versus Chennai; older age; lower education; earning less income; lower BMI; were each associated with tobacco use in both sexes. In addition, semi-skilled occupation versus not working and alcohol use were associated with tobacco use in males, and having newly diagnosed dyslipidemia was associated with lower odds of tobacco use among females. Mean salivary cotinine levels were higher among tobacco users versus nonusers (235.4; CI: 187.0-283.8 vs. 29.7; CI: 4.2, 55.2, respectively).

Conclusion

High prevalence of tobacco use in the South Asian region, particularly among men, highlights the urgency to address this serious public health problem. Our analyses suggest targeted prevention and cessation interventions focused on lower socioeconomic groups may be particularly important.

Electronic supplementary material

The online version of this article (doi:10.1186/s12889-015-1817-z) contains supplementary material, which is available to authorized users.

Survival in South Asian and White European patients after acute myocardial infarction

OBJECTIVE

To examine the association between ethnicity and survival following acute myocardial infarction (AMI) in White European (WE) and South Asian (SA) patients from a multiethnic UK population.

METHODS

Retrospective, cohort study of 4111 (N=730, 17.8% of SA ethnicity) hospitalised patients, with AMI from a tertiary coronary care centre in the UK, admitted between October 2002 and September 2008. The primary end point was all-cause mortality. The association of ethnicity with survival post AMI was assessed using the Cox regression analysis.

RESULTS

Compared with WE patients, SA patients were on average younger (62.0 years vs 67.3 years) and had higher prevalence of cardiovascular risk factors including diabetes (39.7% vs 16.1%). During follow-up (median 912, range 1-2556, days), crude mortality rate was 22.6% in SA patients and 26.0% in WE patients (p = 0.061). SA ethnicity did not show univariate (HR 0.85 (0.72 to 1.01)) or multivariate (HR, 1.12 (0.94 to 1.34)) association with mortality. Findings were similar for mortality during 0-30 days (1.30 (0.99 to 1.70)), > 30 days-1 year (0.97 (0.67 to 1.40)), > 1 year-3 years (1.21 (0.83 to 1.76)), > 3 years (0.82 (0.47 to 1.41)), and for long-term mortality in survivors from 30 days (1.02 (0.81 to 1.29)).

CONCLUSIONS

When adjusted for differing prevalence of cardiovascular risk factors in the two ethnic groups, survival following AMI was similar for SA and WE patients in the UK.

South Asians and Anglo Australians with heart disease in Australia

Objectives The aim of the present study was to determine cardiovascular disease (CVD) risk factors and compare presentation and severity of ischaemic heart disease (IHD) among South Asians (SAs) and Anglo Australians (AAs). Methods A retrospective clinical case audit was conducted at a public tertiary hospital. The study population included SA and AA patients hospitalised for IHD. Baseline characteristics, evidence of diabetes and other CVD risk factors were recorded. Angiography data were also included to determine severity, and these were assessed using a modified Gensini score. Results SAs had lower mean (± s.d.) age of IHD presentation that AAs (52 ± 9 vs 55 ± 9 years, respectively; P = 0.02), as well as a lower average body mass index (BMI; 26 ± 4 vs 29 ± 6 kg/m2, respectively; P = 0.005), but a higher prevalence of type 2 diabetes (57% vs 31%, respectively; P = 0.001). No significant differences were found in coronary angiography parameters. There were no significant differences in the median (interquartile range) Gensini score between SAs and AAs (43.5 (27–75) vs 44 (26.5–68.5), respectively), median vessel score (1 (1–2) vs 2 (1–3), respectively) or multivessel score (37% (33/89) vs 54% (22/41), respectively). Conclusions The findings show that in those with established IHD, cardiovascular risk factors, such as age at onset and BMI, differ between SAs and AAs and these differences should be considered in the prevention and management of IHD. What is known about the topic? There is much evidence on CVD and SAs, it being a leading cause of mortality and morbidity for this population both in their home countries and in countries they have migrated to. Studies conducted in Western nations other than Australia have suggested a difference in the risk profiles and presentations of CVD among SA migrants compared with the host populations in developed countries. Although this pattern of cardiovascular risk factors among SAs has been well documented, there is insufficient knowledge about this population, currently the largest population of incoming migrants, and CVD in the Australian setting. What does this paper add? This paper confirms that a similar pattern of CVD exists in Australia among SAs as does in other Western nations they have migrated to. The CVD pattern found in this population is that of an earlier age of onset at lower BMI compared with the host AA population, as well as a differing cardiovascular risk profile, with higher rates of type 2 diabetes and lower smoking rates. In addition, this study finds similar angiographic results for both the SAs and AAs; however, the SAs exhibit these similar angiographic patterns at younger ages. What are the implications for practitioners? SAs in Australia represent a high cardiovascular risk group and should be targeted for more aggressive screening at younger ages. Appropriate preventative strategies should also be considered bearing in mind the differing risk factors for this population, namely low BMI and high rates of type 2 diabetes. More intensive treatment strategies should also be regarded by practitioners. Importantly, both policy makers and health professionals must consider that all these strategies should be culturally targeted and tailored to this population and not assume a ‘one-size fits all’ approach.

Diabetes and associated complications in the South Asian population

The rising prevalence of diabetes in South Asians has significant health and economic implications. South Asians are predisposed to the development of diabetes due to biologic causes which are exacerbated by lifestyle and environmental factors. Furthermore, they experience significant morbidity and mortality from complications of diabetes, most notably coronary artery disease, cerebrovascular disease, and chronic kidney disease. Therefore, understanding the pathophysiology and genetics of diabetes risk factors and its associated complications in South Asians is paramount to curbing the diabetes epidemic. With this understanding, the appropriate screening, preventative and therapeutic strategies can be implemented and further developed. In this review, we discuss in detail the biologic and lifestyle factors that predispose South Asians to diabetes and review the epidemiology and pathophysiology of microvascular and macrovascular complications of diabetes in South Asians. We also review the ongoing and completed diabetes prevention and management studies in South Asians.

The first 12 weeks following discharge from hospital: The experience of Gujarati South Asian survivors of acute myocardial infarction and their families

The period following discharge from hospital after an acute myocardial infarction (MI) is associated with vulnerability and psychosocial and physical morbidity for many survivors and their families. It is reported that people experience interpersonal, family and financial problems, self-care obstacles, work and physical difficulties. Culture and ethnicity undeniably influence the illness experience and the process of recovery and adjustment. This study investigated the perceptions of Gujarati survivors of acute MI and their families in Leicester, United Kingdom in the first 12 weeks following discharge in order to develop a profile of their health seeking beliefs and needs. Thirty-one interviews with 19 Gujarati MI survivors and their families (representing approximately 31 hours of dialogue) were analysed using grounded theory. Qualitative data revealed a period of vulnerability not only for survivors but also their families as they processed recent events and faced the future. Data analysis revealed nine interrelated themes describing the post-discharge experience for Gujarati survivors and their families. Data revealed that normal life was often markedly changed by the MI experience. Reflection, contemplation and resignation characterize this period of vulnerability. Overwhelmingly, data analysis revealed that the Gujarati culture, beliefs and customs influenced the recovery experience.

Acute Coronary Syndrome in Indian Subcontinent Patients Residing in the Middle East: Results From Gulf Registry of Acute Coronary Events II

We compared baseline characteristics, clinical presentation, and in-hospital outcomes between Middle Eastern Arabs and Indian subcontinent patients presenting with acute coronary syndrome (ACS). Of the 7930 patients enrolled in Gulf Registry of Acute Coronary Events II (RACE II), 23% (n = 1669) were from the Indian subcontinent. The Indian subcontinent patients, in comparison with the Middle Eastern Arabs, were younger (49 vs 60 years; P < .001), more were males (96% vs 80%; P < .001), had lower proportion of higher Global Registry of Acute Coronary Events risk score (8% vs 27%; P < .001), and less likely to be associated with diabetes (34% vs 42%; P < .001), hypertension (36% vs 51%; P < .001), and hyperlipidemia (29% vs 39%; P < .001) but more likely to be smokers (55% vs 29%; P < .001). After multivariable adjustment, the Middle Eastern Arabs were less likely to be associated with in-hospital congestive heart failure (odds ratio [OR], 0.65; 95% confidence interval [CI]: 0.50-0.86; P = .003) but more likely to be associated with recurrent ischemia (OR 1.33; 95% CI: 1.03-1.71; P = .026) when compared to the Indian subcontinent patients. Despite the baseline differences, there were largely no significant differences in in-hospital outcomes between the Indians and the Middle Eastern Arabs.

Diabetes in South Asians

Economic, dietary and other lifestyle transitions have been occurring rapidly in most South Asian countries, making their populations more vulnerable to developing Type 2 diabetes and cardiovascular diseases. Recent data show an increasing prevalence of Type 2 diabetes in urban areas as well as in semi-urban and rural areas, inclusive of people belonging to middle and low socio-economic strata. Prime determinants for Type 2 diabetes in South Asians include physical inactivity, imbalanced diets, abdominal obesity, excess hepatic fat and, possibly, adverse perinatal and early life nutrition and intra-country migration. It is reported that Type 2 diabetes affects South Asians a decade earlier and some complications, for example nephropathy, are more prevalent and progressive than in other races. Further, prevalence of pre-diabetes is high, and so is conversion to diabetes, while more than 50% of those who are affected remain undiagnosed. Attitudes, cultural differences and religious and social beliefs pose barriers in effective prevention and management of Type 2 diabetes in South Asians. Inadequate resources, insufficient healthcare budgets, lack of medical reimbursement and socio-economic factors contribute to the cost of diabetes management. The challenge is to develop new translational strategies, which are pragmatic, cost-effective and scalable and can be adopted by the South Asian countries with limited resources. The key areas that need focus are: generation of awareness, prioritizing health care for vulnerable subgroups (children, women, pregnant women and the underprivileged), screening of high-risk groups, maximum coverage of the population with essential medicines, and strengthening primary care. An effective national diabetes control programme in each South Asian country should be formulated, with these issues in mind.

Culturally appropriate health education for people in ethnic minority groups with type 2 diabetes mellitus

BACKGROUND

Ethnic minority groups in upper-middle-income and high-income countries tend to be socioeconomically disadvantaged and to have a higher prevalence of type 2 diabetes than is seen in the majority population.

OBJECTIVES

To assess the effectiveness of culturally appropriate health education for people in ethnic minority groups with type 2 diabetes mellitus.

SEARCH METHODS

A systematic literature search was performed of the following databases: The Cochrane Library, MEDLINE, EMBASE, PsycINFO, the Education Resources Information Center (ERIC) and Google Scholar, as well as reference lists of identified articles. The date of the last search was July 2013 for The Cochrane Library and September 2013 for all other databases. We contacted authors in the field and handsearched commonly encountered journals as well.

SELECTION CRITERIA

We selected randomised controlled trials (RCTs) of culturally appropriate health education for people over 16 years of age with type 2 diabetes mellitus from named ethnic minority groups residing in upper-middle-income or high-income countries.

DATA COLLECTION AND ANALYSIS

Two review authors independently assessed trial quality and extracted data. When disagreements arose regarding selection of papers for inclusion, two additional review authors were consulted for discussion. We contacted study authors to ask for additional information when data appeared to be missing or needed clarification.

MAIN RESULTS

A total of 33 trials (including 11 from the original 2008 review) involving 7453 participants were included in this review, with 28 trials providing suitable data for entry into meta-analysis. Although the interventions provided in these studies were very different from one study to another (participant numbers, duration of intervention, group versus individual intervention, setting), most of the studies were based on recognisable theoretical models, and we tried to be inclusive in considering the wide variety of available culturally appropriate health education.Glycaemic control (as measured by glycosylated haemoglobin A1c (HbA1c)) showed improvement following culturally appropriate health education at three months (mean difference (MD) -0.4% (95% confidence interval (CI) -0.5 to -0.2); 14 trials; 1442 participants; high-quality evidence) and at six months (MD -0.5% (95% CI -0.7 to -0.4); 14 trials; 1972 participants; high-quality evidence) post intervention compared with control groups who received 'usual care'. This control was sustained to a lesser extent at 12 months (MD -0.2% (95% CI -0.3 to -0.04); 9 trials; 1936 participants) and at 24 months (MD -0.3% (95% CI -0.6 to -0.1); 4 trials; 2268 participants; moderate-quality evidence) post intervention. Neutral effects on health-related quality of life measures were noted and there was a general lack of reporting of adverse events in most studies - the other two primary outcomes for this review. Knowledge scores showed improvement in the intervention group at three (standardised mean difference (SMD) 0.4 (95% CI 0.1 to 0.6), six (SMD 0.5 (95% CI 0.3 to 0.7)) and 12 months (SMD 0.4 (95% CI 0.1 to 0.6)) post intervention. A reduction in triglycerides of 24 mg/dL (95% CI -40 to -8) was observed at three months, but this was not sustained at six or 12 months. Neutral effects on total cholesterol, low-density lipoprotein (LDL) cholesterol or high-density lipoprotein (HDL) cholesterol were reported at any follow-up point. Other outcome measures (blood pressure, body mass index, self-efficacy and empowerment) also showed neutral effects compared with control groups. Data on the secondary outcomes of diabetic complications, mortality and health economics were lacking or were insufficient.Because of the nature of the intervention, participants and personnel delivering the intervention were rarely blinded, so the risk of performance bias was high. Also, subjective measures were assessed by participants who self-reported via questionnaires, leading to high bias in subjective outcome assessment.

AUTHORS' CONCLUSIONS

Culturally appropriate health education has short- to medium-term effects on glycaemic control and on knowledge of diabetes and healthy lifestyles. With this update (six years after the first publication of this review), a greater number of RCTs were reported to be of sufficient quality for inclusion in the review. None of these studies were long-term trials, and so clinically important long-term outcomes could not be studied. No studies included an economic analysis. The heterogeneity of the studies made subgroup comparisons difficult to interpret with confidence. Long-term, standardised, multi-centre RCTs are needed to compare different types and intensities of culturally appropriate health education within defined ethnic minority groups, as the medium-term effects could lead to clinically important health outcomes, if sustained.

Cardiovascular risk among South Asians living in Canada: a systematic review and meta-analysis

BACKGROUND

South Asians represent about 3% of the Canadian population and have a higher burden of certain cardiovascular risk factors and cardiovascular disease (CVD) compared with white people. The objective of this study was to review the literature to compare cardiovascular risk factors and disease management practices among adult South Asian and white Canadians.

METHODS

We searched MEDLINE, Embase, Cochrane and Cumulative Index to Nursing and Allied Health Literature databases from their inception through Feb. 17, 2014 and the reference lists of the selected articles. English-language studies of interventions and observational studies of biological mechanisms underlying CVD risk in South Asians conducted in Canada were eligible for inclusion. Where appropriate, we used random-effects meta-analyses to integrate results comparing the CVD risk profiles of South Asian and white Canadians.

RESULTS

We included 50 articles (n = 5 805 313 individuals) in this review. Compared with white Canadians, South Asian Canadians had a higher prevalence and incidence of CVD, an increased prevalence of diabetes (odds ratio [OR] 2.25, 95% confidence interval [CI] 1.81 to 2.80, p < 0.001) and hypertension (OR 1.11, 95% CI 1.02 to 1.22, p = 0.02), lower high-density lipoprotein cholesterol levels (mean difference -0.19 mmol/L, 95% CI -0.25 to -0.13 mmol/L, p < 0.001) and a higher percentage of body fat (men: absolute mean difference 3.23%, 95% CI 0.83% to 5.62%, p = 0.008; women: absolute mean difference 4.09%, 95% CI 3.46% to 4.72%, p < 0.001). South Asian people are also more sedentary, consume higher levels of carbohydrates and are less likely to smoke tobacco (OR 0.38, 95% CI 0.24 to 0.60, p < 0.001]) than white Canadians. No differences in access to diagnostic tests, outcomes following cardiovascular surgery or use of cardiac rehabilitation programs were apparent.

INTERPRETATION

Compared with white people, South Asian people living in Canada have a higher prevalence and incidence of CVD and possess a unique cardiovascular risk profile.

Acute coronary syndrome and ethnicity: observations from the Middle East

AIMS

To evaluate the presentation and outcome of South Asian (SAP) to Middle Eastern Arabs (MEAP) patients presenting with acute coronary syndrome.

METHODS

Data were collected retrospectively in Qatar between 1991 and 2010, and were analyzed according to patient ethnicity.

RESULTS

Of 14,593 acute coronary syndrome patients, 49% were MEAP and 51% were SAP. When compared with MEAP, SAP were younger, males and smokers (p < 0.01). Other cardiovascular risk factors were less common in SAP when compared with MEAP. ST-elevation myocardial infarction and the use of evidence-based medications were more prevalent among SAP (all p < 0.001). Compared to MEAP, SAP had better in-hospital outcomes; however, ethnicity was not an independent predictor of in-hospital mortality.

CONCLUSION

In contrary to data from Western countries, SAP living in the Middle East are younger with lower cardiovascular risk profile and better outcomes when compared with Arab patients. However, further studies are warranted.

The chromosome 9p21 variant not predicting long-term cardiovascular mortality in Chinese with established coronary artery disease: an eleven-year follow-up study

INTRODUCTION

We examined whether the variant at chromosome 9p21, rs4977574, was associated with long-term cardiovascular mortality in Han Chinese patients with coronary artery disease (CAD).

METHODOLOGY

Subjects who underwent coronary angiography for chest pain were consecutively enrolled. Fasting blood samples were collected for laboratory and genotype assessments. The information was correlated with data collected from the national death database.

RESULTS

There were 925 cases with CAD and 634 without CAD enrolled in the present study. The G allele conferred a significant increase in risk of CAD (odds ratio = 1.47, P = 0.003 in the dominant model; odds ratio = 1.36, P = 0.018 in the recessive model). During a median of 11 years (inter-quartile range between 5.2 and 12.5 years) of follow-up, neither the total nor the cardiovascular mortality was different among CAD subjects with different genotypes. Using Cox regression analysis, genotypes of rs4977574 still failed to predict cardiovascular mortality (hazard ratio = 1.25, P = 0.138 in the dominant model; hazard ratio = 1.05, P = 0.729 in the recessive model).

CONCLUSIONS

The rs4977574 at chromosome 9p21 is associated with presence of CAD in Han Chinese. However, rs4977574 could not predict cardiovascular mortality in these CAD subjects during the eleven-year period of the study.

Risk factors for coronary heart disease among Asian Indians living in Australia

The aim of this study was to assess the coronary heart disease risk factors in the Asian Indian community living in a large city in Australia. A cross-sectional survey was conducted at the Australia India Friendship Fair in 2010. All people of Asian Indian descent who attended the Fair and visited the health promotion stall were eligible to participate in the study if they self-identified as of Asian Indian origin, were aged between 18 and 80 years, and were able to speak English. Blood pressure, blood glucose, waist circumference, height, and weight were measured by a health professional. Smoking, cholesterol levels, and physical activity status were obtained through self-reports. Data were analyzed for 169 participants. More than a third of the participants under the age of 65 years had high blood pressure. Prevalence of diabetes (16%) and obesity (61%) was significantly higher compared with the national average. Ten women identified themselves as smokers. Physical activity patterns were similar to that of the wider Australian population. The study has provided a platform for raising awareness among nurses and promoting advocacy on the cardiovascular risk among Asian Indians. Strategies involving Asian Indian nurses and other Asian Indian health professionals as well as support from the private and public sectors can assist in the reduction of the coronary heart disease risk factors among this extremely susceptible population.

A 5-day high-fat, high-calorie diet impairs insulin sensitivity in healthy, young South Asian men but not in Caucasian men

South Asians (SAs) develop type 2 diabetes at a younger age and lower BMI compared with Caucasians (Cs). The underlying cause is still poorly understood but might result from an innate inability to adapt to the Westernized diet. This study aimed to compare the metabolic adaptation to a high-fat, high-calorie (HFHC) diet between both ethnicities. Twelve healthy, young lean male SAs and 12 matched Cs underwent a two-step hyperinsulinemic-euglycemic clamp with skeletal muscle biopsies and indirect calorimetry before and after a 5-day HFHC diet. Hepatic triglyceride content (HTG) and abdominal fat distribution were assessed using magnetic resonance imaging and spectroscopy. At baseline, SAs had higher insulin clamp levels than Cs, indicating reduced insulin clearance rate. Despite the higher insulin levels, endogenous glucose production was comparable between groups, suggesting lower hepatic insulin sensitivity in SAs. Furthermore, a 5-day HFHC diet decreased the insulin-stimulated (nonoxidative) glucose disposal rate only in SA. In skeletal muscle, no significant differences were found between groups in insulin/mammalian target of rapamycin signaling, metabolic gene expression, and mitochondrial respiratory chain content. Furthermore, no differences in (mobilization of) HTG and abdominal fat were detected. We conclude that HFHC feeding rapidly induces insulin resistance only in SAs. Thus, distinct adaptation to Western food may partly explain their propensity to develop type 2 diabetes.

The potential of Cystatin C and small dense LDL as biomarkers of coronary artery disease risk in a young Indian population

Coronary artery disease (CAD) affects Indians 5-6 years earlier than in the west, is diffuse and malignant, and poses a heavy burden on India's developing economy. Traditional risk factors have failed to explain this high incidence of premature CAD and hence this study investigated the association of two novel risk biomarkers, cystatin C and small dense LDL (sdLDL) with the presence and severity of CAD. Cystatin C and sdLDL were estimated in 204 CAD patients ≤45 years of age and compared with 161 age-matched healthy controls. The traditional lipid profile parameters, i.e., cholesterol, LDL, HDL, triglycerides, apolipoproteins A1 and B, and Lp(a) were also measured in both groups. Cystatin C was significantly raised and mean LDL particle size significantly reduced in CAD patients as compared to controls. 62.7 % of CAD patients showed pattern B while 37.3 % patients showed pattern A. Of the traditional lipid tests, only HDL and apolipoprotein A1 showed a significant decrease in the CAD group. sdLDL was significantly associated with the severity of CAD, while cystatin C was not. Both cystatin C and sdLDL emerged as independent risk factors, however, of the two, sdLDL was a more sensitive predictor of CAD events. Cystatin C and mean LDL particle size are significantly and independently associated with the presence of CAD events in patients ≤45 years with normal kidney function. Hence, these novel risk biomarkers can be useful tools in reducing the morbidity and mortality associated with CAD in the productive Indian workforce.

Myocardial infarction incidence and survival by ethnic group: Scottish Health and Ethnicity Linkage retrospective cohort study

OBJECTIVE

Inequalities in coronary heart disease mortality by country of birth are large and poorly understood. However, these data misclassify UK-born minority ethnic groups and provide little detail on whether excess risk is due to increased incidence, poorer survival or both.

DESIGN

Retrospective cohort study.

SETTING

General resident population of Scotland.

PARTICIPANTS

All those residing in Scotland during the 2001 Census were eligible for inclusion: 2 972 120 people were included in the analysis. The number still residing in Scotland at the end of the study in 2008 is not known.

PRIMARY AND SECONDARY OUTCOME MEASURES

As specified in the analysis plan, the primary outcome measures were first occurrence of admission or death due to myocardial infarction and time to event. There were no secondary outcome measures.

RESULTS

Acute myocardial infarction (AMI) incidence risk ratios (95% CIs) relative to white Scottish populations (100) were highest among Pakistani men (164.1 (142.2 to 189.2)) and women (153.7 (120.5, 196.1)) and lowest for men and women of Chinese (39.5 (27.1 to 57.6) and 59.1 (38.6 to 90.7)), other white British (77 (74.2 to 79.8) and 72.2 (69.0 to 75.5)) and other white (83.1 (75.9 to 91.0) and 79.9 (71.5 to 89.3)) ethnic groups. Adjustment for educational qualification did not eliminate these differences. Cardiac intervention uptake was similar across most ethnic groups. Compared to white Scottish, 28-day survival did not differ by ethnicity, except in Pakistanis where it was better, particularly in women (0.44 (0.25 to 0.78)), a difference not removed by adjustment for education, travel time to hospital or cardiac intervention uptake.

CONCLUSIONS

Pakistanis have the highest incidence of AMI in Scotland, a country renowned for internationally high cardiovascular disease rates. In contrast, survival is similar or better in minority ethnic groups. Clinical care and policy should focus on reducing incidence among Pakistanis through more aggressive prevention.

Patterns and determinants of dyslipidaemia in 'Young' versus 'Not so Young' patients of coronary artery disease: a multicentric, randomised observational study in northern India

AIMS

The aims of the study were to ascertain difference in lipid levels of 'Young' onset of coronary artery disease (CAD) (≤ 45 years) vs. 'Not so Young' onset of CAD (≥ 55 years) among north Indians and also to investigate determinants of 'dyslipidaemia' in CAD patients.

METHODS

This was a prospective, multicentric, randomised, observational study carried in eight centres of UP, India. All blood investigations were performed employing a central laboratory.

RESULTS

Out of a total 435 patients studied, 218 were in the 'young group' (YG) and 235 were in the 'Not so Young Group' (NSYG). Dyslipidaemia was more common in YG as evident by significantly higher levels of total cholesterol, triglycerides, low- and very low-density lipoprotein cholesterol as compared to NSYG. Diabetes, hypertension, urban lifestyle, and family history of CAD were found to be important determinants of dyslipidaemia in YG.

CONCLUSION

We conclude that lipid levels among north Indians are significantly higher in younger patients with CAD when compared with elderly.

Diabetes and coronary artery disease in South Asians

South Asians originate from the Indian sub-continent and represent roughly one fifth of the world’s population. This ethnic group contributes to the highest proportion of coronary artery disease (CAD) burden, mainly attributed to the high prevalence of diabetes. However, other established and emerging risk factors are overrepresented in this population at a younger age. Further large scale research is needed to identify various genetic and environmental mechanisms underlying the increased diabetes and vascular risk in the South Asian population. Effective clinical strategies to reduce the risk of diabetes and CAD in the South Asian population are the need of the hour.

Myocardial infarction in singapore: ethnic variation in evidence-based therapy and its association with socioeconomic status, social network size and perceived stress level

BACKGROUND

Singapore is a multiethnic Asian country comprising predominantly Chinese, Malays, and Indians. We sought to study the disparities in evidence-based therapy for people from these three ethnic groups who were admitted to hospital with ST-segment elevation myocardial infarction (STEMI). We also examined its association with socioeconomic level and social network size and the influence on psychological stress level.

METHODS

In a prospective study, patients admitted with STEMI were recruited for a questionnaire survey. Relevant demographic and clinical data were collected.

RESULTS

A total of 364 patients were recruited and categorised based on ethnicity: Chinese (222 patients), Malays (72 patients), and Indians (70 patients). Malays and Indians were significantly younger than Chinese at the time of presentation with STEMI. Malays had significantly more children than the Chinese and Indians. Malays were in the lowest socioeconomic class, based on education level (P ≤ .02) and residential type (P ≤ .003). Most (87%) patients were treated with primary percutaneous coronary intervention. There were no significant differences between Chinese, Malays, and Indians in accessibility to primary percutaneous coronary intervention, symptom-to-balloon time, door-to-balloon time, and prescription of evidence-based medications. Malays had larger social networks for information support (P ≤ .05) and financial support (P ≤ .04) than Chinese and Indians. There were no significant differences between the three ethnic groups in satisfaction with social support. The perceived stress level was higher among Malays and Indians than Chinese.

CONCLUSIONS

Although Malays were underprivileged in the socioeconomic level, no significant difference in healthcare disparities were observed among the three ethnic groups. This may be a reflection of the advancement in Singapore's healthcare system. The lower socioeconomic level may also explain the higher perceived stress level in Malays.

South Asians and coronary disease: is there discordance between effects on incidence and prognosis?

Objective

To determine whether the effect of South Asian ethnicity differs between studies of incidence and prognosis of coronary disease.

Design

Systematic literature review and meta-analysis, and cohort analysis from a national acute coronary syndrome (ACS) registry linked to mortality (National Institute of Cardiovascular Outcomes Research/Myocardial Infarction National Audit Project).

Setting

International for the review, and England and Wales for the cohort analysis.

Patients

The numbers of South Asians included in the meta-analysis were 111 555 (incidence) and 14 531 (prognosis) of whom 8251 were from the ACS cohort.

Main outcome measures

Incidence studies: non-fatal myocardial infarction or fatal coronary heart disease; prognostic studies: mortality; HRs for 1-year all-cause death in ACS cohort.

Results

South Asians had higher incidence of coronary disease compared with white subjects (HR 1.35 95% CI 1.30 to 1.40) based on meta-analysis of nine studies. Among 10 studies on prognosis, South Asians had better prognosis compared with white subjects (HR 0.78 95% CI 0.74 to 0.82). In the ACS cohort, the impact of diabetes (42.4% of South Asians, 16.9% of white subjects) on 1-year mortality was stronger in South Asians than white subjects (age-adjusted HR 1.83 95% CI 1.59 to 2.11 vs 1.53 95% CI 1.49 to 1.57). However, prognosis was better in South Asians even among diabetics, older people and those living in areas of the highest social deprivation.

Conclusions

South Asian ethnicity is associated with higher incidence of coronary disease, but lower mortality once coronary disease is manifest. The dissociation between effects on incidence and prognosis suggests that public health initiatives to reduce inequalities in mortality between South Asian and white populations should focus on primary prevention.

This is a CALIBER study with ClinicalTrials.gov Identifier: NCT01163513.

Pilot ethnic analysis of routine hospital admissions data and comparison with census linked data: CHD rates remain high in Pakistanis

Purpose

Routine data are needed to monitor ethnic health inequalities. The proportion of hospital discharge records with ethnicity information has been improving in Scotland. The aim of this paper is to assess whether routine data can provide valid comparisons of admission rates by ethnic group.

Design/methodology/approach

Routine hospital admissions data in four NHS Boards were analysed by ethnic group and sex to compare incidence rate ratios (IRRs) for acute myocardial infarction (AMI) and coronary heart disease (CHD). A previous study linking health and census ethnicity information for 2001‐2003 provided the comparison standard.

Findings

There was a similar risk of AMI for South Asian compared to non‐South Asian people in 2009‐2011 and 2001‐2003. South Asian people and Pakistani women had higher risk of CHD than White Scottish people. The Other White group had higher and the White Irish lower risk of AMI admission in comparison to 2001‐2003 data.

Research limitations/implications

The comparison used a different age range, did not include community deaths, covered a part of Scotland rather than the whole, and may have been affected by changes to denominators, which were based on the UK census 2001.

Originality/value

The similar IRRs for AMI from census linkage in 2001‐2003 and NHS data from 2009‐2011 suggest routine ethnicity data are valid in some NHS Boards. Analyses can reveal previously unknown variations to justify health improvement action. To maximise the precision of analyses, data completeness needs to be increased and sustained.

Aggressive and diffuse coronary calcification in South Asian angina patients compared to Caucasians with similar risk factors

BACKGROUND

Ethnic differences in prevalence and severity of coronary artery disease are well established and are usually attributed to risk factors variation. This study investigates the differences in coronary artery narrowing and coronary calcification between two age- and gender-matched cohorts of South Asian and Caucasian symptomatic angina patients.

METHODS

We identified 101 symptomatic angina patients of South Asian origin who had undergone CT angiography and calcium scoring, and compared them with 101 age and gender matched Caucasian patients.

RESULTS

South Asians had a greater mean number of arterial segments with both obstructive and non-obstructive plaque than Caucasians (p=0.006 and p=0.0003, respectively) and higher prevalence of triple-vessel disease (p=0.0004). Similarly, South Asians had a higher mean CAC score (p<0.0001) and the percentage of South Asians with CAC>0 and in all categories of CAC score 100-1000 were also higher, as was the number of arterial segments with calcified and non-calcified plaque. These results were more marked in patients aged >50 but in those ≤ 50, Caucasians showed a higher mean number of diseased segments (p=0.019), with non-obstructive plaque (p=0.02), possibly suggesting that Caucasians are likely to have more diffuse atherosclerosis at an earlier age. CAC prevalence and severity in this age-group were not significantly different between South Asians and Caucasians.

CONCLUSION

Despite similar conventional risk factors for CAD, symptomatic South Asians seem to have more aggressive and diffuse arterial calcification compared to Caucasians. These differences are more profound above the age of 50, suggesting potential genetic or other risk factors yet to be determined.

Ethnic differences in cardiovascular risk in rheumatic disease: focus on Asians

Rheumatic diseases are associated with high cardiovascular morbidity and mortality. Considerable differences exist in the frequency of cardiovascular disease (CVD) risk factors and events among people of different ethnic origins, but little is known of the ethnic variations in the relative distribution of CVD risk factors and the degree of atherosclerosis in patients with rheumatic diseases. Understanding this variation will provide insight into the underlying pathogenesis of CVD in patients with rheumatic diseases, and aid in future studies of the detection and management of this complication. In general, although Asian patients seem to have fewer background CVD risk factors and are less affected by metabolic syndrome (MetS) than their non-Asian counterparts, those with rheumatic disease are equally as susceptible to CVD. Furthermore, it seems that systemic inflammation and mechanisms that do not involve conventional CVD risk factors and MetS have an important role in the development of atherosclerosis in patients with rheumatic diseases. Here we examine the frequency of conventional CVD risk factors and the prevalence of MetS in both Asian and non-Asian patients with selected rheumatic diseases. We also discuss the burden of CVD, as evaluated using various surrogate markers in these patients, and their overall CVD mortality rate.

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.

Type 2 diabetes and cardiovascular disease in South Asians

Type 2 diabetes (T2DM) is growing at a pandemic scale and is associated with a rapid increase in its complications such as cardiovascular diseases (CVD). This problem is even worse in South Asian population with South Asian people having a much higher prevalence of T2DM and CVD, occurring at an earlier age and being associated with premature and high mortality. This review looks in detail at the current knowledge on epidemiology and characteristic pathophysiology of T2DM and CVD (coronary heart disease, heart failure, stroke and peripheral vascular disease) in South Asian migrant population. Specific attention is also drawn to the role of novel risk factors and cultural and socioeconomic factors on occurrence and outcomes of these chronic diseases in this population. Finally the review makes recommendations on various measures including need for further research to tackle this serious health challenge facing the South Asian community.

Prevalence of metabolic syndrome in South Asians residing in the United States

AIMS/HYPOTHESIS

The aim of this study was to define the prevalence of the metabolic syndrome and its component risk factors among individuals of South Asian origin living in the United States.

METHODS

We analyzed baseline data from 1,445 participants enrolled in a cohort study investigating risk factors for cardiovascular disease in South Asians. We defined the metabolic syndrome using the International Diabetes Federation criteria for waist circumference (>90 cm for men; >80 cm, women), triglycerides (>150 mg/dL), high-density lipoprotein cholesterol (HDL-C) (<40 mg/dL (men), < mg/dL (women)), blood pressure (>135/80 mmHg), and fasting glucose (>100 mg/dL).

RESULTS

The mean age was 43 +/-10 years, and 30% of participants were women. The prevalence of metabolic syndrome was 27% (31% men vs. 17% women, P < 0.05). Fifty-nine percent of the cohort had high waist circumference (58% men vs. 62% women, P = not significant [N.S.]), 47% had low HDL-C [46% men vs. 48% women (NS)], 19% had elevated triglycerides (23% men vs. 8% women, P < 0.05), 14% had hypertension (16% men vs. 9% women, P < 0.05), and 13% had elevated fasting glucose (18% men vs. 11% women, P < 0.05). The most common metabolic syndrome phenotype is low HDL-C with elevated triglycerides.

CONCLUSIONS

Although the prevalence of the metabolic syndrome is lower than previous reports of South Asians, the prevalence is still unacceptably high despite the presence of protective demographic factors.

Ethnic and sex differences in the incidence of hospitalized acute myocardial infarction: British Columbia, Canada 1995-2002

Background

As populations in Western countries continue to change in their ethnic composition, there is a need for regular surveillance of diseases that have previously shown some health disparities. Earlier data have already demonstrated high rates of cardiovascular mortality among South Asians and relatively lower rates among people of Chinese descent. The aim of this study was to describe the differences in the incidence of hospitalized acute myocardial infarction (AMI) among the three largest ethnic groups in British Columbia (BC), Canada.

Methods

Using hospital administrative data, we identified all patients with incident AMI in BC between April 1, 1995, and March 31, 2002. Census data from 2001 provided the denominator for the entire BC population. Ethnicity was determined using validated surname analysis and applied to the census and hospital administrative datasets. Direct age standardization was used to compare incidence rates.

Results

A total of 34,848 AMI cases were identified. Among men, South Asians had the highest age standardized rate of AMI hospitalization at 4.97/1000 population/year, followed by Whites at 3.29, and then Chinese at 0.98. Young South Asian men, in particular, showed incidence rates that were double that of young Whites and ten times that of young Chinese men. South Asian women also had the highest age-standardized rate of AMI hospitalization at 2.35/1000 population/year, followed by White women (1.53) and Chinese women (0.49).

Conclusions

South Asians continue to have a higher incidence of hospitalized AMI while incidence rates among Chinese remain low. Ethnic differences are most notable among younger men.

Obesity-related non-communicable diseases: South Asians vs White Caucasians

South Asians are at higher risk than White Caucasians for the development of obesity and obesity-related non-communicable diseases (OR-NCDs), including insulin resistance, the metabolic syndrome, type 2 diabetes mellitus (T2DM) and coronary heart disease (CHD). Rapid nutrition and lifestyle transitions have contributed to acceleration of OR-NCDs in South Asians. Differences in determinants and associated factors for OR-NCDs between South Asians and White Caucasians include body phenotype (high body fat, high truncal, subcutaneous and intra-abdominal fat, and low muscle mass), biochemical parameters (hyperinsulinemia, hyperglycemia, dyslipidemia, hyperleptinemia, low levels of adiponectin and high levels of C-reactive protein), procoagulant state and endothelial dysfunction. Higher prevalence, earlier onset and increased complications of T2DM and CHD are often seen at lower levels of body mass index (BMI) and waist circumference (WC) in South Asians than White Caucasians. In view of these data, lower cut-offs for obesity and abdominal obesity have been advocated for Asian Indians (BMI; overweight >23 to 24.9 kg m(-2) and obesity ≥ 25 kg m(-2); and WC; men ≥ 90 cm and women ≥ 80 cm, respectively). Imbalanced nutrition, physical inactivity, perinatal adverse events and genetic differences are also important contributory factors. Other differences between South Asians and White Caucasians include lower disease awareness and health-seeking behavior, delayed diagnosis due to atypical presentation and language barriers, and religious and sociocultural factors. All these factors result in poorer prevention, less aggressive therapy, poorer response to medical and surgical interventions, and higher morbidity and mortality in the former. Finally, differences in response to pharmacological agents may exist between South Asians and White Caucasians, although these have been inadequately studied. In view of these data, prevention and management strategies should be more aggressive for South Asians for more positive health outcomes. Finally, lower cut-offs of obesity and abdominal obesity for South Asians are expected to help physicians in better and more effective prevention of OR-NCDs.