Do known risk factors explain the higher coronary heart disease mortality in South Asian compared with European men? Prospective follow-up of the Southall and Brent studies, UK

Coronary heart disease in Indian Asians

The Indian Asian population accounts for a fifth of all global deaths from coronary heart disease (CHD). CHD deaths on the Indian subcontinent have doubled since 1990, and are predicted to rise a further 50% by 2030. Reasons underlying the increased CHD mortality among Indian Asians remain unknown. Although conventional cardiovascular risk factors contribute to CHD in Indian Asians as in other populations, these do not account for their increased risk. Type-2 diabetes, insulin resistance and related metabolic disturbances are more prevalent amongst Indian Asians than Europeans, and have been proposed as major determinants of higher CHD risk among Indian Asians. However, this view is not supported by prospective data. Genome-wide association studies have not identified differences in allele frequencies or effect sizes in known loci to explain the increased CHD risk in Indian Asians. Limited knowledge of mechanisms underlying higher CHD risk amongst Indian Asians presents a major obstacle to reducing the burden of CHD in this population. Systems biology approaches such as genomics, epigenomics, metabolomics and transcriptomics, provide a non-biased approach for discovery of novel biomarkers and disease pathways underlying CHD. Incorporation of these ‘omic’ approaches in prospective Indian Asian cohorts such as the London Life Sciences Population Study (LOLIPOP) provide an exciting opportunity for the identification of new risk factors underlying CHD in this high risk population.

Comparison of long-term outcomes between older Asian and white patients with non-ST-segment elevation myocardial infarction: findings from CRUSADE-CMS database

BACKGROUND

In the United States as well as globally, Asians are a growing proportion of patients presenting with non-ST-segment elevation myocardial infarction (NSTEMI), yet little is known about their longitudinal outcomes.

METHODS

We linked Centers for Medicare & Medicaid claims data to detailed clinical data for 37,702 NSTEMI patients ≥65 years old treated at 444 CRUSADE hospitals between 2003 and 2006 to examine longitudinal outcomes. We used Cox proportional hazards modeling to compared outcomes between Asian and white patients, adjusting for differences in baseline patient characteristics.

RESULTS

Compared with white NSTEMI patients, Asians (n = 307) were younger; more frequently had hypertension, diabetes and renal insufficiency; and were less likely to have had a prior myocardial infarction, but there were no significant differences in rates of cardiac catheterization or revascularization during the index hospitalization between the 2 groups. At 30 days, Asian and white patients had a similar risk-adjusted mortality (9.5% vs 9.9%, P = .77), but by 1 year, Asian patients had a significantly lower risk-adjusted mortality (20.9% vs 24.5%, adjusted hazard ratio 0.64, 95% CI 0.50-0.82). Compared with white patients, Asians also had a lower adjusted 1-year cardiovascular readmission risk (37.1% vs 42.1%, adjusted hazard ratio 0.79, 95% CI 0.64-0.98).

CONCLUSIONS

Despite similar inhospital treatments, Asian NSTEMI patients had lower mortality and cardiovascular readmission risks at 1 year, compared with white patients. Further study is needed to determine whether intrinsic ethnic differences or differential longitudinal prevention strategies explain these differences in long-term outcomes.

Mediators of Atherosclerosis in South Asians Living in America (MASALA) study: objectives, methods, and cohort description

BACKGROUND

South Asians (individuals from India, Pakistan, Bangladesh, Nepal, and Sri Lanka) have high rates of cardiovascular disease (CVD) that cannot be explained by traditional risk factors. There are few prospective cohort studies investigating antecedents of CVD in South Asians.

OBJECTIVES

The Mediators of Atherosclerosis in South Asians Living in America (MASALA) study is investigating the prevalence, correlates, and outcomes associated with subclinical CVD in a population-based sample of South Asian men and women age 40-79 years at 2 US clinical field centers.

POPULATION AND METHODOLOGY

This cohort is similar in methods and measures to the Multi-Ethnic Study of Atherosclerosis (MESA) to allow for efficient cross-ethnic comparisons. Measurements obtained at the baseline examination include sociodemographic information, lifestyle and psychosocial factors, standard CVD risk factors, oral glucose tolerance testing, electrocardiography, assessment of microalbuminuria, ankle and brachial blood pressures, carotid intima-media wall thickness using ultrasonography, coronary artery calcium measurement, and abdominal visceral fat measurement using computed tomography. Blood samples will be assayed for biochemical risk factors. Between October 2010 and March 2013, we enrolled 906 South Asians with mean age of 55 ± 9 years (46% women; 98% immigrants who have lived 27 ± 11 years in the United States). The sociodemographic characteristics of this cohort are representative of US South Asians. Participants are being followed with annual telephone calls for identification of CVD events including acute myocardial infarction and other coronary heart disease, stroke, peripheral vascular disease, congestive heart failure, therapeutic interventions for CVD, and mortality.

CONCLUSIONS

The MASALA study will provide novel data on the prevalence and associations of cardiovascular risk factors and subclinical atherosclerosis in South Asians living in the United States.

Microcirculatory rarefaction in South Asians - a potential mechanism for increased cardiovascular risk and diabetes

People of South Asian descent have an increased risk of cardiovascular disease (CVD) and diabetes, but little is known about the microcirculation in South Asian people despite evidence that this plays an important role in the aetiology of CVD. We compared the retinal microcirculation in a population-based sample of 287 middle-aged adults (144 European 143 South Asian) matched for age and sex. Retinal photographs were taken and analysed using a validated semi-automated program and microvascular measures were compared. Blood pressure, anthropometry and fasting bloods were also measured. South Asians had significantly fewer arteriolar and venular vessels and bifurcations. Arterioles and venules were longer and venules were also more tortuous in South Asians. These differences were not explained by adjustment for traditional risk factors including blood pressure, body mass index, diabetes or measures of insulin resistance. People of South Asian descent have rarefaction of the retinal microcirculation compared to age-sex matched individuals of European descent. Reduced microvascular density could contribute to the elevated risk of CVD and impaired glucose tolerance in South Asian people.

Lower cardiorespiratory fitness contributes to increased insulin resistance and fasting glycaemia in middle-aged South Asian compared with European men living in the UK

AIMS/HYPOTHESIS

This study aimed to determine the extent to which increased insulin resistance and fasting glycaemia in South Asian men, compared with white European men, living in the UK, was due to lower cardiorespiratory fitness (maximal oxygen uptake [VO(2max)]) and physical activity.

METHODS

One hundred South Asian and 100 age- and BMI-matched European men without diagnosed diabetes, aged 40-70 years, had fasted blood taken for measurement of glucose concentration, HOMA-estimated insulin resistance (HOMA(IR)), plus other risk factors, and underwent assessment of physical activity (using accelerometry), VO(2max), body size and composition, and demographic and other lifestyle factors. For 13 South Asian and one European man, HbA1c levels were >6.5% (>48 mmol/mol), indicating potential undiagnosed diabetes; these men were excluded from the analyses. Linear regression models were used to determine the extent to which body size and composition, fitness and physical activity variables explained differences in HOMA(IR) and fasting glucose between South Asian and European men.

RESULTS

HOMA(IR) and fasting glucose were 67% (p < 0.001) and 3% (p < 0.018) higher, respectively, in South Asians than Europeans. Lower VO(2max), lower physical activity and greater total adiposity in South Asians individually explained 68% (95% CI 45%, 91%), 29% (11%, 46%) and 52% (30%, 80%), respectively, and together explained 83% (50%, 119%) (all p < 0.001) of the ethnic difference in HOMA(IR). Lower VO(2max) and greater total adiposity, respectively, explained 61% (9%, 111%) and 39% (9%, 76%) (combined effect 63% [8%, 115%]; all p < 0.05) of the ethnic difference in fasting glucose.

CONCLUSIONS/INTERPRETATION

Lower cardiorespiratory fitness is a key factor associated with the excess insulin resistance and fasting glycaemia in middle-aged South Asian, compared with European, men living in the UK.

South Asian Heart Risk Assessment (SAHARA): Randomized Controlled Trial Design and Pilot Study

Background

People of South Asian origin suffer a high burden of premature myocardial infarction (MI). South Asians form a growing proportion of the Canadian population and preventive strategies to mitigate the risk of MI in this group are needed. Prior studies have shown that multimedia interventions are effective and feasible in inducing health behavior changes among the obese, smokers, and among those who are sedentary.

Objective

Among at-risk South Asians living in Canada, our objectives are to determine: (1) the feasibility of a culturally tailored multimedia intervention to induce positive behavioral changes associated with reduced MI risk factors, and (2) the effectiveness and acceptability of information communicated by individualized MI and genetic risk score (GRS) reports.

Methods

The South Asian HeArt Risk Assessment (SAHARA) pilot study enrolled 367 individuals of South Asian origin recruited from places of worship and community centers in Ontario, Canada. MI risk factors including the 9p21 genetic variant status were provided to all participants after the baseline visit. Participants were randomly allocated to receive a multimedia intervention or control. The intervention group selected health goals and received personalized health messages to promote adherence to their selected goals. After 6 months, all participants had their MI risk factors repeated. The methods and results of this study are reported based on the CONSORT-EHEALTH guidelines.

Results

The mean age of participants was 53.8 years (SD 11.4), 52.0% (191/367) were women, and 97.5% (358/367) were immigrants to Canada. The mean INTERHEART risk score was 13.0 (SD 5.8) and 73.3% (269/367) had one or two copies of the risk allele for the 9p21 genetic variant. Both the intervention and control groups made some progress in health behavior changes related to diet and physical activity over 6 months. Participants reported that their risk score reports motivated behavioral changes, although half of the participants could not recall their risk scores at the end of study evaluation. Some components of the multimedia intervention were not widely used such as logging onto the website to set new health goals, and participants requested having more personal interactions with the study team.

Conclusions

Some, but not all, components of the multimedia intervention are feasible and have the potential to induce positive health behavior changes. MI and GRS reports are desired by participants although their impact on inducing sustained health behavior change requires further evaluation. Information generated from this pilot study has directly informed the design of another randomized trial designed to reduce MI risk among South Asians.

Trial Registration

ClinicalTrials.gov NCT01577719; http://clinicaltrials.gov/ct2/show/NCT01577719 (Archived by WebCite at http://www.webcitation.org/6J11uYXgJ).

South Asian individuals at high risk of type 2 diabetes have lower plasma vitamin C levels than white Europeans

Individuals of South Asian origin are at high risk of developing type 2 diabetes; the relationship between this risk and diet remains to be investigated fully. Furthermore, fruit and vegetable intake remains low throughout the world and previous data suggest that intake is associated with risk of diabetes. The aim of this research study was to compare plasma vitamin C concentrations, measured as a biomarker for fruit and vegetable intake, in South Asian and white European individuals. Participants recruited as part of the Let's Prevent Diabetes Study provided samples for the quantification of plasma vitamin C. We compared vitamin C levels by ethnicity using multiple regression, both unadjusted and adjusted for confounders, including glycaemic status. Mean plasma vitamin C was significantly lower in the South Asian participants compared with white European participants (34.5 (sd 19·8) v. 39·9 (sd 22·1) µmol/l, respectively; P ≤ 0·0001). Significantly fewer South Asian individuals consumed five portions of fruit and vegetables per d, as determined by a plasma vitamin C concentration of ≥ 50 µmol/l (23·2 % (n 58) v. 31·4 % (n 558); P = 0·01). Vitamin C reflects habitual fruit and vegetable consumption; thus results suggest that South Asians have lower fruit and vegetable intake. However, it cannot be excluded that vitamin C is utilised differently. Dietary advice specifically targeting the South Asian population should be developed.

South Asians' cardiac medication adherence

AIM

This paper is a report of a narrative review examining the current state of knowledge regarding adherence with cardiac medication among South Asian cardiac patients.

BACKGROUND

South Asians experience higher rates of cardiovascular disease than any other ethnic group. South Asians may be less adherent with a cardiac medication regimen than Caucasians. The factors contributing to adherence are important to discover to assist South Asians to optimize their cardiac health.

DATA SOURCES

CINAHL, Medline (Ovid), PsychINFO, EMB Reviews-(Cochrane), and EMBASE were accessed using the key words: 'South Asian', 'Asia', 'East India', 'India', 'Pakistan', 'Bangladesh', 'Sri Lanka', 'medication compliance', 'medication noncompliance' and 'medication adherence'. English language papers published from January 1980 to January 2013 were eligible for inclusion.

REVIEW METHODS

Abstracts were reviewed for redundancy and eligibility by the primary author. Manuscripts were then retrieved and reviewed for eligibility and validity by the first and last authors. Content analysis strategies were used for the synthesis.

RESULTS

Thirteen papers were in the final data set; most were conducted in India and Pakistan. Medication side-effects, cost, forgetfulness and higher frequency of dosing contributed to non-adherence. South Asian immigrants also faced language barriers, which contributed to non-adherence. Knowledge regarding the medications prescribed was a factor that increased adherence.

CONCLUSION

South Asians' non-adherence to cardiac medications is multifaceted. How South Asians who newly immigrate to Western countries make decisions regarding their cardiac medication adherence ought to be explored in greater detail.

Impaired fasting glucose prevalence in two nationwide cohorts of obese children and adolescents

Objective:

Impaired fasting glucose (IFG), a pre-stage to type 2 diabetes in adults, is also present in obese children. A large variation of the occurrence has been recorded, but the true prevalence is unknown due to lack of larger representative cohort studies. This study was implemented to investigate the prevalence of IFG in two nationwide cohorts of obese children and to find factors that affect the risk of IFG.

Design:

A cross-sectional study based on data collected from two nationwide registers of obese children in Germany and Sweden, respectively.

Subjects:

Subjects included were 2–18 years old. 32 907 subjects with fasting glucose were eligible in Germany and 2726 in Sweden. Two cutoff limits for IFG were used: 5.6–6.9 mmol l⁻¹ according to the American Diabetes Association (ADA) and 6.1–6.9 mmol l⁻¹according to the World Health Organization (WHO). Variables collected were gender, age and degree of obesity. Logistic regression was used to calculate odds ratios.

Results:

The total prevalence of IFG among obese children in the German cohort according to the ADA was 5.7% and according to the WHO it was 1.1%. In Sweden, the corresponding prevalence was 17.1% and 3.9%, respectively. IFG risk was correlated with increasing age, male sex and degree of obesity.

Conclusions:

IFG is highly prevalent among obese children. Age and degree of obesity are positively correlated with the risk of having IFG. There are large regional differences. After adjustments, obese children in Sweden, due to unknown reasons, have a 3.4- to 3.7-fold higher risk of having IFG than obese children in Germany.

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.

The relationship between metabolic risk factors and incident cardiovascular disease in Europeans, South Asians, and African Caribbeans: SABRE (Southall and Brent Revisited) -- a prospective population-based study

Objectives

This study sought to determine whether ethnic differences in diabetes, dyslipidemia, and ectopic fat deposition account for ethnic differences in incident cardiovascular disease.

Background

Coronary heart disease risks are elevated in South Asians and are lower in African Caribbeans compared with Europeans. These ethnic differences map to lipid patterns and ectopic fat deposition.

Methods

Cardiovascular risk factors were assessed in 2,049 Europeans, 1,517 South Asians, and 630 African Caribbeans from 1988 through 1991 (mean age: 52.4 ± 6.9 years). Fatal and nonfatal events were captured over a median 20.5-year follow-up. Subhazard ratios (SHR) were calculated using competing risks regression.

Results

Baseline diabetes prevalence was more than 3 times greater in South Asians and African Caribbeans than in Europeans. South Asians were more and African Caribbeans were less centrally obese and dyslipidemic than Europeans. Compared with Europeans, coronary heart disease incidence was greater in South Asians and less in African Caribbeans. The age- and sex-adjusted South Asian versus European SHR was 1.70 (95% confidence interval [CI]: 1.52 to 1.91, p < 0.001) and remained significant (1.45, 95% CI: 1.28 to 1.64, p < 0.001) when adjusted for waist-to-hip ratio. The African Caribbean versus European age- and sex-adjusted SHR of 0.64 (95% CI: 0.52 to 0.79, p < 0.001) remained significant when adjusted for high-density lipoprotein and low-density lipoprotein cholesterol (0.74, 95% CI: 0.60 to 0.92, p = 0.008). Compared with Europeans, South Asians and African Caribbeans experienced more strokes (age- and sex-adjusted SHR: 1.45 [95% CI: 1.17 to 1.80, p = 0.001] and 1.50 [95% CI: 1.13 to 2.00, p = 0.005], respectively), and this differential was more marked in those with diabetes (age-adjusted SHR: 1.97 [95% CI: 1.16 to 3.35, p = 0.038 for interaction] and 2.21 [95% CI: 1.14 to 4.30, p = 0.019 for interaction]).

Conclusions

Ethnic differences in measured metabolic risk factors did not explain differences in coronary heart disease incidence. The apparently greater association between diabetes and stroke risk in South Asians and African Caribbeans compared with Europeans merits further study.

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.

Conduit vessel stiffness in British south Asians of Indian descent relates to 25-hydroxyvitamin D status

BACKGROUND

South Asians migrating to Northern latitudes are more susceptible to premature cardiovascular disease (CVD) than expected for given levels of blood pressure. Vitamin D deficiency is common in this group and may play an important role mediating vascular wall senescence in response to central pressure effects.

METHODS

A cross-sectional association study. South Asian and White European participants were randomly recruited from a population-based diabetes-screening programme. Carotid-femoral pulse wave velocity (cfPWV), biochemistry (25-hydroxyvitamin D, fasting glucose), anthropometrics, resting blood pressure and a physical activity measure (International Physical Activity Questionnaire) were measured under controlled conditions.

PARTICIPANTS

One hundred and thirty-two and 125 age-matched South Asians and White Europeans not taking vitamin D supplementation with a risk factor for diabetes but no overt CVD.

RESULTS

Age (mean south Asian: 55.7 vs. White European: 56.0 years), mean arterial pressure (MAP) and calculated CVD risk were similar in both groups. Unadjusted (cf)PWV (m/s) was higher (9.32 vs. 8.68 P = 0.001) and 25-hydroxyvitamin D (nmol/l) lower in (21.29 vs. 52.5 P < 0.001) south Asians. 25-Hydroxyvitamin D independently associated with cfPWV in multivariate modelling adjusted for age, MAP, sex, glucose, heart rate, vasoactive medication and south Asian ethnicity (R = 0.73, P = 0.004). 25-Hydroxyvitamin D but not physical activity was negatively correlated with cfPWV independent of south Asian ethnicity.

CONCLUSION

Aortic stiffness is increased in British Indo-Asians without vascular disease despite conventional risk profiles, which are comparable to age-matched white Europeans. This effect may be mediated by a greater pressure-dependent increase in stiffness in individuals with vitamin D insufficiency.

Why Do South Asians Have High Risk for CAD?

South Asians have a higher risk for coronary artery disease (CAD) due to both pathophysiological and life course-related risk factors. We performed a literature search and used qualitative synthesis to present evidence for CAD risk factors among South Asians. A large proportion of the higher risk of South Asians for CAD can be explained by conventional risk factors. However, several conditioning factors such as education, socioeconomic status, and fetal programming, and early life influences may contribute to excess CAD risk in South Asians, suggesting the need for a life course approach. Evidence on unconventional risk factors is provocative but comes from small studies. Large-scale, well-designed epidemiological studies are needed for an in-depth understanding of the CAD risk among South Asians.

Insulin initiation and management in people with Type 2 diabetes in an ethnically diverse population: the healthcare provider perspective

AIM

To explore barriers to prescribing of insulin, particularly delays in initiation, from the perspective of healthcare professionals involved in managing Type 2 diabetes in a multi-ethnic setting.

METHODS

The study was carried out in a UK population with high numbers of people of South Asian (mainly Indian) origin. Semi-structured interviews were conducted with 14 healthcare professionals from primary and secondary care. Analysis involved exploring interview transcripts in terms of themes and sub-themes identified through a process of progressive focusing.

RESULTS

Initiation of insulin therapy was described as challenging in all patients irrespective of ethnicity, but some barriers were perceived to be accentuated because of language needs and lower levels of understanding about diabetes and insulin. Additionally, some South Asians were viewed as more likely than their white European counterparts to be influenced by negative observations and experiences about insulin therapy within community networks. Time restrictions were seen as a barrier that was accentuated in the management of South Asian patients. Participants suggested strategies for overcoming patient barriers; with South Asians these included involvement of families and patient peers and availability of South Asian healthcare providers.

CONCLUSION

The challenge for healthcare providers is to how to address the tension between the optimal clinical time for commencing insulin therapy and the time when the patient feels psychologically ready. To help make these two time points coincide, our findings suggest the need to adopt a holistic approach involving consideration of the cultural context of patients, including their ethnic background.

Ethnic differences in disability prevalence and their determinants studied over a 20-year period: a cohort study

Background

To compare disability prevalence rates in the major ethnic groups in the UK and understand the risk factors contributing to differences identified. It was hypothesised that Indian Asian and African Caribbean people would experience higher rates of disability compared with Europeans.

Methods

Data was collected from 888 European, 636 Indian Asian and 265 African Caribbean men and women, aged 58–88 years at 20-year follow-up of community-based cohort study, based in West London. Disability was measured using a performance-based locomotor function test and self-reported questionnaires on functional limitation, and instrumental (IADL) and basic activities of daily living (ADL).

Results

The mean (SD) age of participants at follow-up was 69.6 (6.2) years. Compared with Europeans, Indian Asian people were significantly more likely to experience all of the disability outcomes than Europeans; this persisted after adjustment for socioeconomic, behavioural, adiposity and chronic disease risk factors measured at baseline (locomotor dysfunction: adjusted odds ratio (OR) 2.20, 95% CI 1.56–3.11; functional limitation: OR 2.77, 2.01–3.81; IADL impairment: OR 3.12, 2.20–4.41; ADL impairment: OR 1.58, 1.11–2.24). In contrast, a modest excess risk of disability was observed in African Caribbeans, which was abolished after adjustment (e.g. locomotor dysfunction: OR 1.37, 0.90–1.91); indeed a reduced risk of ADL impairment appeared after multivariable adjustment (OR from 0.99, 0.68–1.45 to 0.59, 0.38–0.93), compared with Europeans.

Conclusions

Substantially elevated risk of disability was observed among Indian Asian participants, unexplained by known factors. A greater understanding of determinants of disability and normative functional beliefs of healthy aging is required in this population to inform intervention efforts to prevent disability.

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.

Metabolic syndrome in South Asians

South Asia is home to one of the largest population of people with metabolic syndrome (MetS). The prevalence of MetS in South Asians varies according to region, extent of urbanization, lifestyle patterns, and socioeconomic/cultural factors. Recent data show that about one-third of the urban population in large cities in India has the MetS. All classical risk factors comprising the MetS are prevalent in Asian Indians residing in India. The higher risk in this ethnic population necessitated a lowering of the cut-off values of the risk factors to identify and intervene for the MetS to prevent diabetes and cardiovascular disease. Some pharmacological and nonpharmacological interventions are underway in MetS to assess the efficacy in preventing the diabetes and cardiovascular disease in this ethnic population.

Impaired post-ischaemic microvascular hyperaemia in Indian Asians is unexplained by diabetes or other cardiovascular risk factors

OBJECTIVE

People of Indian Asian descent have an increased risk of cardiovascular disease (CVD) that cannot be explained by diabetes and other established CVD risk factors. We investigated if microcirculatory function was impaired in a population-based sample of people of Indian Asian descent compared with Europeans in the UK and whether any differences could be accounted for by diabetes or other CVD risk factors.

RESEARCH DESIGN AND METHODS

Cutaneous microvascular function was assessed using laser Doppler fluximetry in response to heating to 42 °C (maximum hyperaemia) and 3 min arterial occlusion (post occlusive reactive hyperaemia: PORH) in 148 Indian Asians and 147 Europeans. Blood pressure, anthropometry and fasting bloods were also measured.

RESULTS

Maximum hyperaemia and minimum resistance did not differ significantly by ethnicity. Resting flux and PORH were lower in Indian Asians and time to peak of PORH was prolonged. Diabetes was associated with reduced maximum hyperaemia and PORH. Adjustment for diabetes accounted for differences in resting flux and time to peak but not differences in PORH (Europeans = 45.0 (40.3, 50.1)au, Indian Asians = 35.6 (31.9, 39.7)au, mean (95% confidence interval); p = 0.008 after adjustment). Differences in conventional CVD risk factors did not account for interethnic differences in microvascular responses.

CONCLUSIONS

People of Indian Asian descent have impaired post-occlusive reactive hyperaemia unexplained by diabetes, dysglycaemia or other CVD risk factors. Abnormal microvascular function in response to ischaemia could represent a novel mechanism contributing to the elevated risk of CVD in Indian Asians.

Screening for diabetes using an oral glucose tolerance test within a western multi-ethnic population identifies modifiable cardiovascular risk: the ADDITION-Leicester study

AIMS/HYPOTHESIS

The aim of this study was to determine the frequency of undiagnosed glucose abnormalities and the burden of cardiovascular disease (CVD) risk among south Asians and white Europeans attending a systematic screening programme for type 2 diabetes (ADDITION-Leicester) and to estimate the achievable risk reduction in individuals identified with glucose disorders.

METHODS

Random samples of individuals (n = 66,320) from 20 general practices were invited for a 75 g OGTT and CVD risk assessment. Ten-year CVD risk among screen-detected people with diabetes or impaired glucose regulation (IGR) (impaired fasting glycaemia and/or impaired glucose tolerance [IGT]) was computed using the Framingham-based ETHRISK engine and achievable risk reduction was predicted using relative reductions for treatments extracted from published trials.

RESULTS

A total of 6,041 participants (48% male, 22% south Asian) aged 40-75 years inclusive were included. Undiagnosed glucose disorders occurred more frequently in south Asians than white Europeans; age and sex adjusted odds ratios were 1.74 (95% CI 1.42-2.13) and 2.30 (95% CI 1.68-3.16) for IGT and diabetes respectively. Prevalence of any undetected glucose disorder was 17.5% in the whole cohort. Adjusted 10-year risk was similar in screen-detected people with IGR and diabetes (18.3% vs 21.6%), and was higher in south Asians across the glucose spectrum. Absolute CVD risk reductions of up to 13% in those with screen-detected type 2 diabetes and 6% in IGR are achievable using existing cardioprotective therapies.

CONCLUSIONS/INTERPRETATION

Population screening with an OGTT identifies a significant burden of modifiable CVD risk, especially within south Asian groups. Strategies enticing this population to consider screening programmes are urgently needed as significant risk reduction is possible once a glucose abnormality is identified.

TRIAL REGISTRATION

ClinicalTrials.gov NCT00318032.

FUNDING

The project is funded for support and treatment costs by NHS Department of Health Support for Science and project grants.

[Are there any clinical and metabolic differences between immigrant and Spanish-born diabetic patients?]

AIM

To determine the clinical features and the metabolic control in immigrant diabetic patients in two Primary Care centres in La Rioja, Spain.

DESIGN

Descriptive study.

SETTING

Two urban Primary Care centres which cover a population of 11,700 and 23,000 patients in Logroño.

PRIMARY OUTCOMES

Socio-demographic variables (age, sex, origin country of origin, age at onset of diabetes), clinical variables (blood pressure, waist circumference (WC), high, weight, BMI) and analytical variables (fasting blood glucose, HbA1c, lipid profile). The immunology of DM and baseline C-peptide were studied in patients younger than 40 years old.

PARTICIPANTS

A total of 70 diabetic immigrants, aged between 18 and 70 years old and registered until December 31(st) 2009, and 70 Spanish-born diabetic patients were selected by consecutive sampling.

RESULTS

The final sample consisted of 140 patients (70 immigrants, 70 Spanish). Mean age of Spanish-born diabetics, 55.5 years, of immigrants 45.7 years (P=.002).Age at diagnosis 38.4 years in immigrants and 48.1 years in autochthonous (P=.004).WC in immigrants 104.1cm, in Spanish-born, 105.3 cm (P=.56).BMI in immigrants 29, in Spanish-born 32.1 (P=.06).Mean glycated haemoglobin (HbA1c) in immigrants 8.4%, in Spanish-born 7.5% (P=.002). Blood pressure and lipid values were lower in Hindustani and North African patients than in Spanish-born and other immigrant groups.

CONCLUSIONS

Immigrant diabetic patients are younger at diagnosis, have an unchanged baseline C-peptide secretion, higher HbA1c levels, higher WC with lower BMI compared to Spanish-born patients.

Can novel Apo A-I polymorphisms be responsible for low HDL in South Asian immigrants?

Coronary artery disease (CAD) is the leading cause of death in the world. Even though its rates have decreased worldwide over the past 30 years, event rates are still high in South Asians. South Asians are known to have low high-density lipoprotein (HDL) levels. The objective of this study was to identify Apolipoprotein A-I (Apo A-I) polymorphisms, the main protein component of HDL and explore its association with low HDL levels in South Asians. A pilot study on 30 South Asians was conducted and 12-h fasting samples for C-reactive protein, total cholesterol, HDL, low-density lipoprotein (LDL), triglycerides, Lipoprotein (a), Insulin, glucose levels, DNA extraction, and sequencing of Apo A-I gene were done. DNA sequencing revealed six novel Apo A-I single nucleotide polymorphisms (SNPs) in South Asians, one of which (rs 35293760, C938T) was significantly associated with low (<40 mg/dl) HDL levels (P = 0.004). The association was also seen with total cholesterol (P = 0.026) and LDL levels (P = 0.032). This pilot work has highlighted some of the gene-environment associations that could be responsible for low HDL and may be excess CAD in South Asians. Further larger studies are required to explore and uncover these associations that could be responsible for excess CAD risk in South Asians.

Low Mannose-Binding Lectin (MBL) genotype is associated with future cardiovascular events in type 2 diabetic South Asians. A prospective cohort study

BACKGROUND

South Asians have a high burden of type 2 diabetes and vascular complications. Vascular inflammation is considered central in the pathophysiology of atherosclerosis, and the complement system is thought to play an important role. Mannose-Binding Lectin (MBL), which activates the lectin pathway of complement activation, has been introduced as a risk marker of vascular damage. The present study explores the association of MBL levels, genotype and cardiovascular events in type 2 diabetic South Asians.

METHODS

We conducted a prospective observational study. A cohort consisting of 168 type 2 diabetic South Asians was followed for a median duration of 7.66 years. At baseline, MBL levels and genotype were determined. The association with future cardiovascular events was assessed by Cox proportional hazard regression.

RESULTS

During follow-up, 31 cardiovascular events occurred in 22 subjects (11 men, 11 women). The O/O genotype was significantly associated with the occurrence of cardiovascular events (hazard ratio 3.42, 95%CI 1.24-9.49, P = 0.018). However, log MBL levels were not associated with the occurrence of cardiovascular events (hazard ratio 0.93, 95% CI 0.50-1.73).

CONCLUSIONS

In type 2 diabetic South Asians, the O/O MBL genotype is associated with cardiovascular events, although single serum MBL levels are not.

Childhood cardiovascular risk factors in South Asians: A cause of concern for adult cardiovascular disease epidemic

Cardiovascular risk factors in children are increasing at an alarming rate in the western world. However, there is limited information regarding these in the South Asian children. This review attempts at summarizing such evidence. South Asians are remarkable for the earlier onset of adult cardiovascular disease (CVD) by almost a decade compared to the Caucasians. We identified published literature, mainly on PubMed, Embase and Cochrane library using specific search terms such as lipid abnormalities, high blood pressure, hyperglycemia, tobacco use, obesity, physical inactivity, and unhealthy dietary practices. Atherosclerotic CVD processes begin early in childhood and are influenced over the life course by genetic and potentially modifiable risk factors and environmental exposure. 80% of adult CVD burden will fall on the developing nations by 2020. The concept of primordial prevention is fast emerging as a necessary prevention tool to curb adult CVD epidemic. Established guidelines and proven preventive strategies on cardiovascular health exist; however, are always implemented half-heartedly. Composite screening and prediction tools for adults can be adapted and validated in children tailored to South Asian population. South Asian children could be at a greater risk of developing cardiovascular risk factors at an earlier stage, thus, timely interventions are imperative.

South Asians have adverse cerebrovascular haemodynamics, despite equivalent blood pressure, compared with Europeans. This is due to their greater hyperglycaemia

BACKGROUND

South Asians have a 1.5-fold increased stroke mortality compared with Europeans, despite similar blood pressures (BP). We hypothesized that it is the greater hyperglycaemia in South Asians that increases stroke risk, by adversely affecting cerebrovascular haemodynamics.

METHODS

A population-based sample of 149 Europeans and 151 South Asians underwent metabolic profiling and concurrent measurement of finger BP using a Finapres and middle cerebral artery (MCA) blood flow velocity using transcranial Doppler ultrasound. Cerebrovascular autoregulation, cerebrovascular resistance [resistive index (RI) and pulsatility index (PI)] were calculated. Means of cerebrovascular haemodynamic measures were compared by ethnicity, with the introduction of explanatory variables to a regression model to determine which variable could best account for ethnic differences.

RESULTS

Cerebrovascular resistance (RI) was 12.9 × 10(3) (0.9-24.8, P = 0.04) greater in South Asians than Europeans. Systolic, diastolic and mean MCA velocities were also higher in South Asians (mean velocity 41.4 ± 8.0 cm/s vs 38.0 ± 8.0 cm/s, respectively, P = 0.001). Low frequency gain, a measure of autoregulation, was worse in South Asians compared with Europeans (0.50 ± 0.01 cm/s mm/Hg vs 0.45 ± 0.01 cm/s mm/Hg, P = 0.01). RI positively correlated with HbA(1c) (r = 0.184; P < 0.01). Adjustment for BP could not explain the higher RI in South Asians, but adjustment for HbA(1c) abolished the ethnic difference in RI (5.8 × 10(3) (-6.5 to 18.1, P = 0.4).

CONCLUSIONS

Cerebrovascular resistance and autoregulation are worse in South Asians than in Europeans, despite equivalent resting BP. The greater hyperglycaemia in South Asians accounts for their adverse cerebrovascular resistance. This could explain excess stroke in South Asians but requires testing in longitudinal studies.

Ethnic differences in aortic pulse wave velocity occur in the descending aorta and may be related to vitamin D

We studied aortic pulse wave velocity (aPWV), a predictor of cardiovascular events independent of blood pressure, in a multiethnic sample of British men, to investigate the roles for blood levels of vitamin D and aldosterone in total and regional aortic stiffness. Total aPWV was estimated noninvasively by the Arteriograph device (aPWV(AG)) in 198 men, with its length measure calibrated by magnetic resonance. PWVs over the aortic arch and descending aorta were measured by magnetic resonance in a subsample (n=47). Mean (SE) aPWV(AG) in South Asians (n=68; age 55±10 years), at known higher coronary disease risk than other groups, was 0.5 m/s (0.2 m/s) higher than in African Caribbeans (n=67; 55±10 years), at lowest coronary disease risk here, and Europeans (n=63; 57±8 years), adjusted for age, systolic blood pressure, and diabetes mellitus (P=0.01). By magnetic resonance, PWV over the descending aorta in South Asians was 0.7 m/s (0.3 m/s) and 0.8 m/s (0.3 m/s) higher than in African Caribbeans and Europeans, respectively; PWV over the aortic arch was not different. South Asians and African Caribbeans had 21 nmol/L (3 nmol/L) and 14 nmol/L (3 nmol/L) lower mean (SE) 25(OH)D than Europeans (P<0.001). Unlike aldosterone, 25(OH)D was negatively correlated with aPWV(AG) adjusted for age and systolic blood pressure, as well as weakened or removed ethnic differences in aPWV(AG) in regression models. These data suggest that aortic stiffness as aPWV parallels coronary disease risk in ethnic groups, descending aortic but not arch PWV has this feature, and serum 25(OH)D is an independent negative correlate of aPWV and may partly account for ethnicity-related differences in aPWV and coronary disease risk.

Prevalence of coronary artery calcium scores and silent myocardial ischaemia was similar in Indian Asians and European whites in a cross-sectional study of asymptomatic subjects from a U.K. population (LOLIPOP-IPC)

BACKGROUND

Coronary heart disease (CHD) mortality is 70% higher among Indian Asians (IA) than European whites (EW), the reasons for this excess remain unexplained. Coronary artery calcification (CAC) is highly correlated with coronary plaque burden and silent myocardial ischaemia in EW; but fails to identify excess risk in IA. We hypothesised that IA have a higher prevalence of silent myocardial ischaemia compared to EW, despite similar CAC, and this may explain their excess CHD mortality.

METHODS

CAC was measured for 2,369 asymptomatic men and women, aged 35 to 75 years, as part of the London Life Sciences Population (LOLIPOP) study. 518 subjects had CAC scores >100 Agatston units and of these 256 (49%) patients underwent myocardial perfusion scintigraphy (MPS).

RESULTS

CAC scores were similar among IA and EW, after adjustment for conventional risk factors. MPS abnormalities were seen in 56 (22%) subjects. Presence of diabetes (P = .03) and increasing CAC (P < .001) were independent predictors for severity of silent myocardial ischaemia. Ethnicity did not influence the prevalence or the extent of silent myocardial ischaemia.

CONCLUSION

MPS did not identify greater ischaemia among IA compared with EW. This appears incongruent with almost 2-fold higher risk of CHD mortality observed in IA.

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.

The prediabetic period: review of clinical aspects

Hyperglycemia that does not satisfy the diagnostic criteria for diabetes mellitus (DM) is generally called prediabetes (preDM). The global prevalence of preDM has been increasing progressively in the past few decades, and it has been established that preDM status is a strong risk factor for DM and cardiovascular disease. Currently, preDM status is classified into two subtypes: impaired fasting glucose and impaired glucose tolerance. Currently, preDM is not regarded as an independent clinical entity, but only as a risk factor for others. In this article, we review various clinical aspects of preDM in terms of the working definition, changes in criteria over the years, epidemiology, and pathophysiological characteristics, and its clinical significance in current medicine.

Prescribing in general practice for people with coronary heart disease; equity by age, sex, ethnic group and deprivation

OBJECTIVE

Differences in drug prescribing for coronary heart disease have previously been identified by age, sex and ethnic group. Set in the UK, our study utilises routinely collected data from 98 general practices serving a socially diverse population in inner East London, to examine differences in prescribing rates among patients aged 35 years and over with coronary heart disease.

DESIGN

10,933 patients aged 35 years or more, with recorded coronary heart disease, from 98 practices in two Primary Care Trusts (PCT) in East London during 2009/2010 were included for this cross-sectional study. Multivariable logistic regression was used to assess the odds of prescribing for recommended coronary heart disease drugs by age, sex, ethnicity, social deprivation, co-morbidity and recorded reasons for not prescribing.

RESULTS

Women are prescribed fewer recommended coronary heart disease drugs than men; Black African/Caribbean patients are prescribed fewer lipid modifying drugs and other cardiovascular drugs than White patients. Patients over age 84 are prescribed fewer lipid modifying drugs and beta blockers than patients aged 45-54. South Asian patients had the highest levels of prescribing and higher prevalence of coronary heart disease and diabetes co-morbidity. No difference in prescribing rates by social deprivation was found.

DISCUSSION

Overall levels of prescribing are high but small differences between sex and ethnic groups remain and prescribing may be inequitable for women, for Black/African Caribbeans and at older ages. These differences were not explained by recorded intolerance, contraindications or declining treatment.

South Asian ethnicity as a risk factor for major adverse cardiovascular events after renal transplantation

BACKGROUND AND OBJECTIVES

South Asians (SAs) comprise 25% of all Canadian visible minorities. SAs constitute a group at high risk for cardiovascular disease in the general population, but the risk in SA kidney transplant recipients has never been studied.

DESIGN, SETTING, PARTICIPANTS, & MEASUREMENTS

In a cohort study of 864 kidney recipients transplanted from 1998 to 2007 and followed to June 2009, we identified risk factors including ethnicity associated with major cardiac events (MACEs, a composite of nonfatal myocardial infarction, coronary intervention, and cardiac death) within and beyond 3 months after transplant. Kaplan-Meier methodology and multivariate Cox regression analysis were used to determine risk factors for MACEs.

RESULTS

There was no difference among SAs (n = 139), whites (n = 550), blacks (n = 65), or East Asians (n = 110) in baseline risk, including pre-existing cardiac disease. Post-transplant MACE rate in SAs was 4.4/100 patient-years compared with 1.31, 1.16, and 1.61/100 patient-years in whites, blacks, and East Asians, respectively (P < 0.0001 versus each). SA ethnicity independently predicted MACEs along with age, male gender, diabetes, systolic BP, and prior cardiac disease. SAs also experienced more MACEs within 3 months after transplant compared with whites (P < 0.0001), blacks (P = 0.04), and East Asians (P = 0.006). However, graft and patient survival was similar to other groups.

CONCLUSIONS

SA ethnicity is an independent risk factor for post-transplant cardiac events. Further study of this high-risk group is warranted.

Incidence and prognosis of angina pectoris in South Asians and Whites: 18 years of follow-up over seven phases in the Whitehall-II prospective cohort study

BACKGROUND

Whether the higher coronary mortality in South Asians compared with White populations is due to a higher incidence of disease is not known. This study assessed cumulative incidence of chest pain in South Asians and Whites, and prognosis of chest pain.

METHODS

Over seven phases of 18-year follow-up of the Whitehall-II study (9,775 civil servants: 9,195 White, 580 South Asian), chest pain was assessed using the Rose questionnaire. Coronary death/non-fatal myocardial infarction was examined comparing those with chest pain to those with no chest pain at baseline.

RESULTS

South Asians had higher cumulative frequencies of typical angina by Phase 7 (17.0 versus 11.3%, P < 0.001) and exertional chest pain (15.4 versus 8.5%, P < 0.001) compared with Whites. Typical angina and exertional chest pain at baseline were associated with a worse prognosis compared with those with no chest pain in both groups (typical angina, South Asians: HR, 4.67 and 95% CI, 2.12-0.30; Whites: HR, 3.56 95% CI, 2.59-4.88). Baseline non-exertional chest pain did not confer a worse prognosis. Across all types of pain, prognosis was worse in South Asians.

CONCLUSION

South Asians had higher cumulative incidence of angina than Whites. In both, typical angina and exertional chest pain were associated with worse prognosis compared with those with no chest pain.

Indian Asians have poorer cardiovascular autonomic function than Europeans: this is due to greater hyperglycaemia and may contribute to their greater risk of heart disease

AIMS/HYPOTHESIS

A high prevalence of diabetes contributes to excess CHD in Indian Asians, but the underlying mechanisms are unclear. Heart rate, heart rate variability (HRV) and baroreflex sensitivity (BRS) are measures of cardiac autonomic function that are disturbed by hyperglycaemia and predict CHD. We compared these measures in Indian Asians and Europeans, and sought explanations for the observed differences.

METHODS

A representative sample of 149 Europeans and 151 Indian Asians was recruited from primary care, 66% of them men (aged 35-75 years), 34% women (aged 55-75 years). Heart rate, HRV, BRS and cardio-metabolic profiles were measured over four successive 5 min periods with continuous ECG and blood pressure monitoring.

RESULTS

Indian Asians were hyperglycaemic compared with Europeans (HbA(1c) (mean +/- SD) 6.5 +/- 1.2% vs 5.9 +/- 1.0%, p = 0.001). They had shorter mean RR intervals ((mean +/- SE) 969 +/- 13 vs 1,022 +/- 12 ms, p = 0.002), lower total RR interval power ((geometric mean, 95% CI) 925 [796-1075] vs 1,224 [1,064-1,422] ms(2), p = 0.008) and lower BRS ((mean +/- SE) 5.7 +/- 1.0 vs 6.6 +/- 1.0 ms/mmHg, p = 0.01). All measures of cardiac autonomic dysfunction were significantly associated with hyperglycaemia (mean RR interval vs HbA(1c) r = -0.22; p < 0.001). Ethnic differences in cardiac autonomic function persisted after adjustment for age, blood pressure and medication (mean RR interval 973 vs 1,021 ms, p = 0.004), but were attenuated or abolished by adjusting for HbA(1c) (979 vs 1,014 ms, p = 0.06) or other markers of hyperglycaemia.

CONCLUSIONS/INTERPRETATION

Indian Asians from the general population have impaired cardiovascular autonomic function compared with Europeans. This is due to greater hyperglycaemia in Indian Asians and may determine their increased CHD risk.

Subgroup differences in psychosocial factors relating to coronary heart disease in the UK South Asian population

OBJECTIVES

To explore the differences in psychosocial risk factors related to coronary heart disease (CHD) between South Asian subgroups in the UK. South Asian people suffer significantly higher rates of CHD than other ethnic groups, but vulnerability varies between South Asian subgroups, in terms of both CHD rates and risk profiles. Psychosocial factors may contribute to the excess CHD propensity that is observed; however, subgroup heterogeneity in psychosocial disadvantage has not previously been systematically explored.

METHODS

With a cross-sectional design, 1065 healthy South Asian and 818 white men and women from West London, UK, completed psychosocial questionnaires. Psychosocial profiles were compared between South Asian religious groups and the white sample, using analyses of covariance and post hoc tests.

RESULTS

Of the South Asian sample, 50.5% was Sikh, 28.0% was Hindu, and 15.8% was Muslim. Muslim participants were more socioeconomically deprived and experienced higher levels of chronic stress, including financial strain, low social cohesion, and racial discrimination, compared with other South Asian religious groups. In terms of health behaviors, Muslim men smoked more than Sikhs and Hindus, and Muslims also reported lower alcohol consumption and were less physically active than other groups.

CONCLUSION

This study found that Muslims were exposed to more psychosocial and behavioral adversity than Sikhs and Hindus, and highlights the importance of investigating subgroup heterogeneity in South Asian CHD risk.

Reductions in risk factors for secondary prevention of coronary heart disease by ethnic group in south-west London: 10-year longitudinal study (1998-2007)

OBJECTIVES

To explore trends by ethnicity in clinical risk factor recording and control among patients with coronary heart disease (CHD), during a period of major investment in quality improvement initiatives in general practice in England.

DESIGN

Longitudinal study from 1998 to 2007, using general practice data extracted from electronic patient records of all adult patients (n=177,412) registered in 2007.

SETTING

Twenty-nine general practices in Wandsworth south-west London.

SUBJECTS

Three thousand two hundred registered patients with a recorded diagnosis of CHD, in 2007.

MAIN OUTCOME MEASURES

Mean systolic and diastolic blood pressure and mean cholesterol of patients with CHD, for each calendar year.

RESULTS

From 1998 to 2007, the proportion of patients with CHD who had their blood pressure recorded rose from 33.2% to 93.9% and cholesterol from 21.7% to 83.5%. Over this period, mean blood pressure decreased from 140/80 to 133/74 mmHg (P<0.001). There was a reduction in mean cholesterol from 5.2 to 4.3 mmol/l (P<0.001). Reductions in mean blood pressure and cholesterol occurred across all ethnic groups.

CONCLUSIONS

From 1998 to 2007, risk factor control among patients with CHD improved, with reductions in their mean blood pressure and cholesterol across all ethnic groups. Widespread policy change has helped to improve the quality and equity of primary care for heart disease patients. Health improvements predated implementation of the Quality and Outcomes Framework and have since continued. Our findings illustrate how a national health care system with universal coverage can significantly reduce inequalities and improve chronic disease care for all ethnic groups.

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.

The changes in early phase insulin secretion in newly diagnosed, drug naive korean prediabetes subjects

Background

There have been no systematic observations regarding changes in early phase insulin secretion among Korean prediabetes and early stage type 2 diabetes mellitus (T2DM) patients.

Methods

We conducted 75-g oral glucose tolerance tests (OGTT) in 873 subjects with suspected abnormal glucose tolerance. All subjects were diagnosed as having normal glucose tolerance (NGT), prediabetes (preDM), or T2DM according to the OGTT results and the insulin secretory and insulin resistance indices of each subject were calculated. Additionally, we analyzed the changes in early phase insulin secretion according to changes in fasting (Glc₀), post-prandial (Glc₁₂₀) glucose and HbA1c (A1c) levels.

Results

As compared to subjects with NGT, the insulin secretory indices of the preDM and T2DM subjects progressively declined, and the insulin resistance indices were progressively aggravated. Early phase insulin secretion decreased rapidly according to the increments of Glc₀, Glc₁₂₀ and A1c, and these changes were most prominent in the NGT stage. Compared to the control group, the early phase insulin secretion levels of the preDM or T2DM subjects were less than 50% when Glc₀ was over 100 mg/dL, Glc₁₂₀ was over 145 mg/dL, and A1c was over 5.8%.

Conclusion

This study suggests that progressive beta cell dysfunction in Koreans may be initiated and rapidly aggravated during the period generally designated as 'normal.'

The tsim tsoum approaches for prevention of cardiovascular disease

The Tsim Tsoum Concept means that humans evolved on a diet in which nature recommends to ingest fatty acids in a balanced ratio (polyunsaturated(P) : saturated(S) =w-6 : w-3 = 1 : 1)as part of dietary lipid pattern where monounsaturated fatty acids(MUFA) is the major fatty acid(P : M : S = 1 : 6 : 1) in the background of other dietary factors; antioxidants, vitamins, minerals and fiber as well as physical activity and low mental stress. Several hundred years ago, our diet included natural foods; fruits, vegetables, green vegetables, seeds, eggs and honey. Fish, and wild meat were also available to pre-agricultural humans which shaped modern human genetic nutritional requirement. Cereal grains (refined), and vegetable oils that are rich in w-6 fatty acids are relatively recent addition to the human diet that represent dramatic departure from those foods to which we are adapted. Excess of linoleic acid, trans fatty acids (TFA), saturated and total fat as well as refined starches and sugar are proinflammatory. Low dietary MUFA and n-3 fatty acids and other long chain polyunsarurated fatty acids (LCPUFA) are important in the pathogenesis of metabolic syndrome. Increased sympathetic activity with greater secretion of neurotransmitters in conjunction of underlying long chain PUFA deficiency, and excess of proinflammatory nutrients, may damage the neurons via proinflammatory cytokines, in the ventromedial hypothalamus and insulin receptors in the brain.Since, 30–50% of the fatty acids in the brain are LCPUFA, especially omega-3 fatty acids, which are incorporated in the cell membrane phospholipids, it is possible that their supplementation may be protective.Blood lipid composition does reflect one's health status: (a) circulating serum lipoproteins and their ratio provide information on their atherogenicity to blood vessels and (b) circulating plasma fatty acids, such as w-6/w-3 fatty acid ratio, give indication on proinflammatory status of blood vessels, cardiomyocytes, liver cells and neurones; (a) and (b) are phenotype-related and depend on genetic, environmental and developmental factors. As such, they appear as universal markers for holistic health and these may be important in the pathogenesis of cardiovascular diseases and cancer, which is the main consideration of Tsim Tsoum concept.