Corrigendum to "Ferritin as a Risk Factor for Glucose Intolerance amongst Men and Women Originating from the Indian Subcontinent".

[This corrects the article DOI: 10.1155/2015/924387.].

Tipping the balance: Haemoglobinopathies and the risk of diabetes.

AIM: To establish a link between the risk of diabetes with haemoglobinopathies by examining available evidence of the effects of iron and blood glucose homeostasis from molecular to epidemiological perspectives. METHODS: A systematic literature search was performed using electronic literature databases using various search terms. The International Diabetes Federation World Atlas was used to generate a list of populations with high rates of diabetes. PubMed, Scopus and Google Scholar were used to identify which of these populations also had a reported prevalence of haemoglobin abnormalities. RESULTS: Abnormalities in iron homeostasis leads to increases in reactive oxygen species in the blood. This promotes oxidative stress which contributes to peripheral resistance to insulin in two ways: (1) reduced insulin/insulin receptor interaction; and (2) ß-cell dysfunction. Hepcidin is crucial in terms of maintaining appropriate amounts of iron in the body and is in turn affected by haemoglobinopathies. Hepcidin also has other metabolic effects in places such as the liver but so far the extent of these is not well understood. It does however directly control the levels of serum ferritin. High serum ferritin is found in obese patients and those with diabetes and a meta-analysis of the various studies shows that high serum ferritin does indeed increase diabetes risk. CONCLUSION: From an epidemiological standpoint, it is plausible that the well-documented protective effects of haemoglobinopathies with regard to malaria may have also offered other evolutionary advantages. By contributing to peripheral insulin resistance, haemoglobinopathies may have helped to sculpt the so-called "thrifty genotype", which hypothetically is advantageous in times of famine. The prevalence data however is not extensive enough to provide concrete associations between diabetes and haemoglobinopathies - more precise studies are required.

Ferritin as a Risk Factor for Glucose Intolerance amongst Men and Women Originating from the Indian Subcontinent.

Background. Serum ferritin predicts the onset of diabetes; however, this relationship is not clear amongst South Asians, a population susceptible to glucose intolerance and anaemia. Objective. This study tests whether ferritin levels reflect glucose tolerance in South Asians, independent of lifestyle exposures associated with Indian or British residence. Methods. We randomly sampled 227 Gujaratis in Britain (49.8 (14.4) years, 50% men) and 277 contemporaries living in Gujarati villages (47.6 (11.8) years, 41% men). Both groups underwent a 75 g oral-glucose-tolerance test. We evaluated lifestyle parameters with standardised questionnaires and conducted comprehensive clinical and lab measurements. Results. Across sites, the age-adjusted prevalence of diabetes was 9.8%. Serum ferritin was higher amongst diabetics (P = 0.005), irrespective of site, gender, and central obesity (P ≤ 0.02), and was associated with fasting and postchallenge glucose, anthropometry, blood pressure, triglycerides, and nonesterified fatty acids (P < 0.001). Diabetes was less in those with low ferritin (<20 mg/mL), P < 0.008, and risk estimate = 0.35 (95% CI 0.15-0.81), as were blood pressure and metabolic risk factors. On multivariate analysis, diabetes was independently associated with ferritin (P = 0.001) and age (P < 0.001). Conclusion. Ferritin levels are positively associated with glucose intolerance in our test groups, independent of gender and Indian or UK lifestyle factors.

CD36 expression and lipid metabolism following an oral glucose challenge in South Asians.

AIM: To investigate lipid metabolism and the relationship with monocyte expression of the fatty acid translocase CD36 in South Asians. METHODS: An observational study of South Asians whom as an ethnic group have - a higher risk of developing diabetes. The susceptibility to diabetes is coupled with an earlier and more rapid progression of micro-, and macro-vascular complications. Twenty-nine healthy South Asian participants [mean age 34.6 (8.9) years, 76.2% male, mean body-mass index 25.0 (5.2) kg/m(2)] were recruited from an urban residential area of central Birmingham (United Kingdom). The main outcomes measured were post prandial (30 min) and post absorptive (120 min) changes from fasting (0 min) in circulating lipoproteins, lipds and hormones, and monocyte expression of CD36 post injection of a 75 g oral glucose challenge. The inducements of variations of monocyte CD36 expression were analysed. RESULTS: Our results showed evident changes in monocyte CD36 expression following the glucose challenge (P < 0.001). Non-esterified fatty acids (NEFA) levels decreased progressively during the challenge (P < 0.001), in contrast to increased cholesterol (but not triglyceride) concentrations within very low density lipoprotein (VLDL) and low density lipoprotein subfractions (P < 0.01). Levels of, glucose, serum triglycerides and high density lipoprotein cholesterol remained largely unchanged. Variations of monocyte CD36 were negatively (r = -0.47, P = 0.04) associated to fat from the diet and positively to carbohydrate from the diet (r = 0.65, P < 0.001). CONCLUSION: These data suggest that the initiation of VLDL genesis follows the consumption of glucose within this population, inferring that the sequestration of NEFA from these particles happens due to the increased availability of CD36 receptors. While these are preliminary results, it would appear that lifestyle exposures have a role in moderating the expression of CD36.

Subclinical thyroid dysfunction and cardiac function amongst minority ethnic groups in the UK: a cross sectional study.

BACKGROUND: Subclinical thyroid disease is associated with abnormal cardiovascular haemodynamics and increased risk of heart failure. The burden of raised/low thyroid stimulating hormone (TSH) levels amongst South Asian (SA) and African-Caribbean (AC) minority groups in the UK is not well defined. Given that these groups are particularly susceptible to CVD, we hypothesised that STD would reflect abnormal cardiac function and heightened cardiovascular risk in these ethnic groups. METHODS: We examined SA (n=1111, 56% male, mean age 57.6 yrs) and AC (n=763, 44% male, mean age 59.2 yrs) participants from a large heart failure screening study. Euthyroidism is defined as TSH (0.4 - 4.9 mlU/l), subclinical hypothyroidism is defined as a raised TSH with normal serum free thyroxine (FT4) concentrations (9-19 pmol/l). Subclinical hyperthyroidism is defined as a low TSH with both FT4 and free triiodothyronine (FT3) concentrations within range (2.6-5.7 pmol/l). RESULTS: Across ethnic groups, prevalence of subclinical hypothyroidism was 2.9% (95% CI 2.1-3.7), and of hyperthyroidism was 2.0% (1.4-2.7). Hyperthyroidism was more common amongst SA compared to AC (2.8% vs. 0.9%, P=0.017), while rates of subclinical hypothyroidism were similar. On multivariate analysis of variations in subclinical thyroid function, ethnicity was not independently significant. CONCLUSION: The prevalence of subclinical thyroid disorders amongst SA and AC minority groups in Britain reflects levels reported in other populations. The clinical cardiovascular significance of subclinical thyroid disease is unclear, and it does not appear to be ethnically specific.

Cardiovascular Risk Profiles amongst Women in a Multiethnic Population in Inner City Britain: A Potential Impact of Anaemia.

The risk of diabetes is markedly reduced in men with iron deficiency anaemia (IDA). The nature of this relationship in women is not clear, nor is there information about the influence of ethnicity, given the increased susceptibility of diabetes amongst South Asians and Afro-Caribbeans. We reviewed 3563 patients with a diagnosis of anaemia from 2000 to 2007. The age-adjusted prevalence of vitamin B12 deficiency and IDA was calculated, together with cardiovascular comorbidities amongst Caucasians, South Asians, and Afro-Caribbeans. The prevalence of vitamin B12 deficiency (women only) or IDA was markedly higher in South Asians compared to Caucasians and Afro-Caribbeans. Among women with IDA, diabetes was more prevalent among South Asians (45%, 95% CI 39.0-51.0) compared to Caucasians (3.0%, 2.1-4.0); P < 0.001. Among South Asian women with vitamin B12 deficiency, the prevalence of diabetes was reduced 8.5% (5.2-12.0). South Asian women with vitamin B12 deficiency had a higher prevalence of myocardial infarction (MI) and ischemic heart disease (IHD), but this relationship was reversed in IDA. IDA is associated with a greater prevalence of diabetes in South Asian women, but it is not coordinated by a greater risk of macrovascular complications. Given the cardiovascular impact of diabetes in South Asians, this association merits further study in relation to its pathophysiological implication.

Role of microRNAs in cardiac remodelling: new insights and future perspectives.

Cardiac remodelling is a key process in the progression of cardiovascular disease, implemented in myocardial infarction, valvular heart disease, myocarditis, dilated cardiomyopathy, atrial fibrillation and heart failure. Fibroblasts, extracellular matrix proteins, coronary vasculature, cardiac myocytes and ionic channels are all involved in this remodelling process. MicroRNAs (miRNAs) represent a sizable sub-group of small non-coding RNAs, which degrade or inhibit the translation of their target mRNAs, thus regulating gene expression and play an important role in a wide range of biologic processes. Recent studies have reported that miRNAs are aberrantly expressed in the cardiovascular system under some pathological conditions. Indeed, in vitro and in vivo models have revealed that miRNAs are essential for cardiac development and remodelling. Clinically, there is increasing evidence of the potential diagnostic role of miRNAs as potential diagnostic biomarkers and they may represent a novel therapeutic target in several cardiovascular disorders. This paper provides an overview of the impact of several miRNAs in electrical and structural remodelling of the cardiac tissue, and the diagnostic and therapeutic potential of miRNA in cardiovascular disease.

Is the higher risk of cardiovascular disease amongst South Asian populations linked to abnormalities of haemoglobin? A preliminary case control study.

The elevated burden of cardiovascular disease (CVD) amongst South Asian populations is a complex and multi-factorial phenomenon. South Asians evolved from environments where malaria was endemic, and while haemoglobin disorders frequent this group, a link to CVD has not been described. Using a case-control feasibility study, haemoglobin abnormalities identified by mass spectrometry were compared between South Asian patients with CVD (n = 72) and non-CVD controls (n = 84). Carotid-artery intima media thickness (CIMT) was used as a marker of vascular damage. Ultracentrifugation was used to separate lipoprotein subfractions, which were analysed for iron. Haemoglobin anomalies were more frequent for CVD patients than controls (34.7% vs. 14.3%, P < 0.001), as were subfractionated lipoprotein concentrations of iron (P < 0.001). Patients with haemoglobin disorders had greater CIMT (0.75 vs. 0.65 mm, P = 0.008), and lower HDL cholesterol (0.78 vs. 1.03 mmol/l, P = 0.003). These preliminary data suggest that haemoglobin disorders contribute to atherosclerotic disease in South Asians and further research is warranted.

Vitamin D deficiency amongst minority ethnic groups in the UK: a cross sectional study.

BACKGROUND: Vitamin D deficiency is common amongst minority groups in Britain but its magnitude amongst South Asian (SA) and Black African-Caribbean (AC) groups is not well defined. The steroidal, endocrine nature of vitamin D provides it with a putative link with cardiovascular disease (CVD), and we hypothesised that aberrant levels of this hormone would reflect a heightened risk of CVD in these ethnic groups. METHODS: SA (n=1105, 57% male) and AC (n=748, 51% male) were recruited as part of a community heart failure study from 20 primary care practices, Birmingham, UK. Vitamin D2/D3 levels were measured to determine rates of total vitamin D status, which were age/sex adjusted. RESULTS: The majority of SAs had severe vitamin D deficiency (42.2%, 95% CI: 39.2-45.1), which was more frequent than in AC (12.5%, 10.2-14.9, p<0.001. Vitamin status in SA and AC was unrelated to the presence of osteoporosis, and on multivariate analysis of SA, vitamin D levels were independently associated with age (ß=0.18, p<0.001), haemoglobin (ß=0.12, p=0.002), and negatively with alkaline phosphatase (a marker of bone mineralisation, ß=-0.11, p=0.022). Amongst AC, vitamin D was independently associated with having ever smoked (ß=-0.13, p=0.006) and systolic blood pressure (ß=0.10, p=0.038). CONCLUSIONS: Vitamin D deficiency is a frequent biochemical observation amongst minority groups in Britain but the clinical significance is unclear, and ethnically specific. A proportionate susceptibility to bone disease is not apparent in either minority group.

Hospital delay in South Asian patients with acute ST-elevation myocardial infarction in the UK.

BACKGROUND: South Asians presenting with chest pain in the UK experience disproportionately greater delays with respect to diagnosis and treatment for acute myocardial infarction (AMI). The duration of time between symptom onset and hospital intervention is a critical delay for AMI but there are limited data amongst South Asians. The objectives of this study were to investigate ethnic differences in hospital delay and to look at short-term outcomes in South Asian and White patients presenting with AMI. METHODS: Between 2004 and 2009, data were collected from 672 AMI patients with ST elevation who subsequently received percutaneous coronary intervention at Sandwell and West Birmingham Hospitals NHS Trust (UK). The hospital delay between the onset of symptoms and arrival time (pre-hospital), and between arrival time and intervention (post-hospital) was calculated. RESULTS: South Asians were more likely to be in the upper tertile of hospital delay (pre-hospital odds ratio, OR, 1.44, 95% CI 0.93-2.24, p = 0.06; post-hospital OR 1.83, 95% CI 1.05-3.21, p = 0.015), contributing to an overall hospital delay that was longer (median 314, interquartile range, IQR, 195-679 min) than in Whites (median 240, IQR 182-468 min). Women were more likely to be in the upper tertile for pre-hospital delay than men (p = 0.01) and South Asian ethnicity was an independent predictor of post-hospital delay (p = 0.003). CONCLUSIONS: While the reasons for ethnic differences in AMI-related hospital delay are likely to be multifactorial and complex, there is an urgent need to promote change in both the South Asian patient (delays in arrival) and their treatment (delays in intervention).

Diabetes Health, Residence & Metabolism in Asians: the DHRMA study, research into foods from the Indian subcontinent - a blinded, randomised, placebo controlled trial.

BACKGROUND: Coronary heart disease (CHD) is highly prevalent amongst the South Asian communities in Britain. The reasons for this excess CHD risk are multifactorial, but in part relate to a susceptibility to diabetes mellitus - where the aberrant metabolism of non-esterified fatty acids (NEFA) and glucose are likely to underpin vascular disease in this population. Dietary intervention is an important and first line approach to manage increased CHD risk. However, there is limited information on the impact of the South Asian diet on CHD risk. METHODS/DESIGN: The Diabetes Health, Residence & Metabolism in Asians (DHRMA) study is a blinded, randomised, placebo controlled trial that analyses the efficacy of reduced glycaemic index (GI) staples of the South Asian diet, in relation to cardio-metabolic risk factors that are commonly perturbed amongst South Asian populations - primarily glucose, fatty acid and lipoprotein metabolism and central adiposity. Using a 10-week dietary intervention study, 50 healthy South Asians will be randomised to receive either a DHRMA (reduced GI) supply of chapatti (bread), stone ground, high protein wheat flour and white basmati rice (high bran, unpolished) or commercially available (leading brand) versions chapatti wheat flour and basmati rice. Volunteers will be asked to complete a 75g oral glucose tolerance test at baseline and at 10-weeks follow-up, where blood metabolites and hormones, blood pressure and anthropometry will also be assessed in a standardised manner. DISCUSSION: It is anticipated that the information collected from this study help develop healthy diet options specific (but not exclusive) for South Asian ethnic communities. Trial registration Current Controlled Trials ISRCTN02839188.

Isolated low levels of high-density lipoprotein cholesterol are associated with an increased risk of coronary heart disease: an individual participant data meta-analysis of 23 studies in the Asia-Pacific region.

BACKGROUND: Previous studies have suggested that there is a novel dyslipidemic profile consisting of isolated low high-density lipoprotein cholesterol (HDL-C) level that is associated with increased risk of coronary heart disease, and that this trait may be especially prevalent in Asian populations. METHODS AND RESULTS: Individual participant data from 220 060 participants (87% Asian) in 37 studies from the Asia-Pacific region were included. Low HDL-C (HDL <1.03 mmol/L in men and <1.30 mmol/L in women) was seen among 33.1% (95% confidence interval [CI], 32.9-33.3) of Asians versus 27.0% (95% CI, 26.5-27.5) of non-Asians (P<0.001). The prevalence of low HDL-C in the absence of other lipid abnormalities (isolated low HDL-C) was higher in Asians compared with non-Asians: 22.4% (95% CI, 22.2-22.5) versus 14.5% (95% CI, 14.1-14.9), respectively (P<0.001). During 6.8 years of follow-up, there were 574 coronary heart disease and 739 stroke events. There was an inverse relationship between low HDL-C with coronary heart disease in all individuals (hazard ratio, 1.57; 95% CI, 1.31-1.87). In Asians, isolated low levels of HDL-C were as strongly associated with coronary heart disease risk as low levels of HDL-C combined with other lipid abnormalities (hazard ratio, 1.67 [95% CI, 1.27-2.19] versus 1.63 [95% CI, 1.24-2.15], respectively). There was no association between low HDL-C and stroke risk in this population (hazard ratio, 0.95 [95% CI, 0.78 to 1.17] with nonisolated low HDL-C and 0.81 [95% CI, 0.67-1.00] with isolated low HDL-C). CONCLUSION: Isolated low HDL-C is a novel lipid phenotype that appears to be more prevalent among Asian populations, in whom it is associated with increased coronary risk. Further investigation into this type of dyslipidemia is warranted.

Characterisation and validity of inflammatory biomarkers in the prediction of post-operative atrial fibrillation in coronary artery disease patients.

Atrial fibrillation (AF) is a common complication of coronary artery bypass grafting (CABG). We sought to determine the diagnostic validity of plasma biomarkers of i) inflammation (marked by interleukin-6 [IL-6] and high-sensitivity C-reactive protein [hs-CRP]), ii) extracellular matrix remodelling (matrix metalloproteinase [MMP-9], tissue inhibitor of matrix metalloproteinase [TIMP-1]) and iii) the prothrombotic state (tissue factor and von Willebrand factor [vWF]) in the risk prediction of post-operative AF. Samples were obtained preoperatively from peripheral/femoral vein and from intracardiac chambers (right atrium [RA], the right atrial appendage [RAA], the left atrium [LA] and the left atrial appendage [LAA]) amongst 100 consecutive patients free of AF and inflammatory disease undergoing elective CABG. Biomarker concentrations were related to incident AF (30 days). At 30 days post CABG, 30 patients were proven to have had AF. Concentrations of tissue factor (TF) and vWF were unrelated to postoperative AF. Peripheral (p=0.018), and intracardiac levels (RAA (p=0.029) and LA (p=0.026)) of hs-CRP were associated with the presence of AF after CABG. Intracardiac levels of IL-6 in samples from the RAA (p=0.031), LA (p=0.042) and LAA (p=0.006), and MMP-9 in the LAA sample were also associated with AF (p=0.007). Our data suggest that an intra-cardiac inflammatory environment that is manifest peri-operatively may predispose to the development of post-operative AF. This intracardiac inflammatory state was reflected by increased peripheral hs-CRP levels. These differences may indicate local substrate abnormalities contributing to the development of AF post-operatively.

Apolipoproteins in the discrimination of atherosclerotic burden and cardiac function in patients with stable coronary artery disease.

AIMS: To compare the performance of apolipoproteins (Apo) and oxidized LDL against routine clinical lipid profiles in the discrimination of atherosclerotic burden and cardiac function in stable coronary artery disease (CAD) patients. METHODS AND RESULTS: Using a cross-sectional approach, we measured oxidized LDL, Apo AI and B in 199 patients (34-81 years) with stable symptomatic CAD. The discrimination of (i) atherosclerotic burden (coronary atheroma scores, the number of diseased coronary vessels), and (ii) cardiac function [NYHA classification, left-ventricular systolic dysfunction (LVSD)] were judged using receiver operating characteristic (ROC) curves. The ratio of Apo AI to B was correlated to oxidized LDL (Spearman, r = 0.37, P < 0.001); however, oxidized LDL was unrelated to measures of cardiac function or CAD severity. Concentrations of Apo AI decreased from 1.38 to 1.20 g/L with increasing atheroma scores (P = 0.02), while triglyceride levels increased from 1.50 to 2.23 mmol/L (P = 0.016). High-density lipoprotein (HDL) cholesterol and Apo AI levels were higher among those with heart failure (P = 0.002), and increased ordinally with NYHA class (P = 0.005). On ROC analysis, reduced levels of Apo AI and HDL cholesterol were discriminators for patients in the upper quartile for atheroma score (P < 0.004). Raised indices of HDL were associated with heart failure (P < 0.002). CONCLUSION: Apo AI levels are a consistent discriminator of atherosclerotic burden among patients with stable CAD. However, heart failure presents an element of confounding in the diagnostic and prognostic utility of Apo monitoring among these patients.

Plasma indices of angiogenesis in rheumatoid disease: relationship to cardiovascular risk factors and cardiac function.

INTRODUCTION: Rheumatoid Disease (RD) is associated with increased rates of cardiovascular disease (CVD). Angiogenesis is central to RD, and well-recognized in CVD. We hypothesised that plasma levels of two indices associated with angiogenesis, vascular endothelial growth factor (VEGF) and angiogenin, would be higher among RD patients compared to healthy controls (HC), would relate to CVD risk factors, calculated 10-year coronary heart disease (CHD) and stroke risk scores. METHODS: 144 clinic patients with established RD and 63 HC were recruited in a cross-sectional study. RD patients were grouped according to the presence (RD-CVD, n=73 or absence (non-CVD RD; n=71) of CVD risk factors. Angiogenin and VEGF levels were quantified by ELISA. RESULTS: There were no significant differences for VEGF or angiogenin, between RD-CVD, non-CVD RD and HC groups (p=NS). Calculated risks for both CHD (p=0.017) and stroke (p=0.016) were higher when RD-CVD was compared to non-CVD RD and HC. Upon multivariate analysis, methotrexate use (p=0.006) and prior mycocardial infarction (MI) (p=0.034) were associated with higher angiogenin levels; body mass index (BMI) (p=0.034) and presence of RD (p=0.029) itself predicted lower levels. For RD patients, serum creatinine (p<0.001) and CRP levels, VEGF levels, and NSAID/COX2 inhibitor use (all p<0.05) were independently associated with CHD risk; plasma VEGF and serum creatinine levels were independently associated with stroke risk (p<0.05). CONCLUSIONS: Although levels of angiogenin were not significantly different between HC and RD patients, RD may have some influence on their variation. Methotrexate use and prior MI predicted higher angiogenin levels, whilst levels of VEGF were negatively associated with 10-year CHD and stroke risk.

Omega-3 polyunsaturated fatty acids: a necessity for a comprehensive secondary prevention strategy.

Long-chain omega-3 polyunsaturated fatty acid (PUFA) supplementation has been used for the secondary prevention of fatal and nonfatal myocardial infarction (MI). However, the benefit of this therapy is frequently confused with other established treatments in the therapeutic strategy among such patients. We review the data on omega-3 PUFA use in secondary care and consider indications for its use which include post-MI and raised triglycerides. We suggest that the available evidence supports the use of omega-3 supplementation as part of the comprehensive secondary care package for post-MI patients.

Glycemic status underlies increased arterial stiffness and impaired endothelial function in migrant South Asian stroke survivors compared to European Caucasians: pathophysiological insights from the West Birmingham Stroke Project.

BACKGROUND: The pathophysiology of an increased risk of cerebrovascular disease mortality among South Asians (SA) remains unclear. Indices of arterial stiffness and endothelial dysfunction are independent markers of vascular disease, having both prognostic and diagnostic implications. We hypothesized that there are ethnic variations in indices of arterial stiffness and endothelial dysfunction between SA and European Caucasian (EC) stroke patients, which may underline a poorer prognosis in the former, and further investigated promoters of vessel wall abnormalities. METHODS: Using a cross-sectional approach, a total of 100 SA stroke survivors were prospectively recruited from the ongoing West Birmingham Stroke Project. Indices of vessel wall characteristics (arterial stiffness and endothelial function [change in reflective index]) were measured noninvasively using the digital volume pulse analysis technique in a temperature-controlled environment, using a direct standardized approach. SA stroke subjects were compared to 60 EC stroke survivors, 60 SA with risk factors, and 73 healthy controls. RESULTS: Among stroke patients, both ethnic groups were comparable for cardiovascular risk profile, except for more diabetes mellitus in SA (P=0.007) subjects and a higher prevalence of atrial fibrillation in EC (P=0.04) subjects. According to the TOAST and Bamford classifications, SA subjects had more small vessel (P=0.04) and lacunar infarctions (P=0.01). SA subjects had higher measurements of arterial stiffness (P<0.001) and impaired endothelial-dependent vascular function (change in reflective index %; P<0.001). On univariate analysis, endothelial function was negatively correlated with fasting plasma glucose (r=-0.4; P<0.001) and total cholesterol level (r=-0.2; P<0.001). On multivariate analysis, glycemic status was independently associated with impaired endothelial function (P=0.008) and increased arterial stiffness (P<0.001) among SA subjects. CONCLUSIONS: SA stroke survivors had more small vessel disease-related cerebrovascular events compared to EC subjects. Underlying glycemic status in SA subjects had an adverse impact on the vascular system, leading to abnormal vessel wall characteristics.

Ischemic stroke in South Asians: a review of the epidemiology, pathophysiology, and ethnicity-related clinical features.

BACKGROUND AND PURPOSE: Within the United Kingdom, mortality from stroke is higher among South Asians compared to European whites. The reasons for this excess cerebrovascular risk in South Asians remain unclear. The aim of this review is to present a comprehensive and systematic overview of the available literature relating to ischemic stroke among South Asian populations identifying distinct features of stroke epidemiology in this group. SUMMARY OF REVIEW: A high frequency of lacunar strokes is a familiar pattern among South Asians, which suggests a greater prevalence of small-vessel disease in South Asians. This may be a consequence of abnormal metabolic and glycemic processes. In addition, stroke mortality among South Asians appears to be explained by glycemic status, which is an independent predictor of long-term stroke mortality. Within India, there is a perceptible rural-urban gradient in stroke prevalence, underlying the dangers of the rapid transition in socioeconomic circumstances seen across the Indian subcontinent. CONCLUSIONS: This review emphasizes the importance of further research into ischemic stroke for South Asians given their higher cardiovascular disease burden and necessity for targeted healthcare approaches.