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.

Diabetes in South Asians

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

Symposium on 'nutrition interventions in high-risk groups' - CVD risk in South Asians: the importance of defining adiposity and influence of dietary polyunsaturated fat

The prevalence of the metabolic syndrome (MetS), CVD and type 2 diabetes (T2D) is known to be higher in populations from the Indian subcontinent compared with the general UK population. While identification of this increased risk is crucial to allow for effective treatment, there is controversy over the applicability of diagnostic criteria, and particularly measures of adiposity in ethnic minorities. Diagnostic cut-offs for BMI and waist circumference have been largely derived from predominantly white Caucasian populations and, therefore, have been inappropriate and not transferable to Asian groups. Many Asian populations, particularly South Asians, have a higher total and central adiposity for a similar body weight compared with matched Caucasians and greater CVD risk associated with a lower BMI. Although the causes of CVD and T2D are multi-factorial, diet is thought to make a substantial contribution to the development of these diseases. Low dietary intakes and tissue levels of long-chain (LC) n-3 PUFA in South Asian populations have been linked to high-risk abnormalities in the MetS. Conversely, increasing the dietary intake of LC n-3 PUFA in South Asians has proved an effective strategy for correcting such abnormalities as dyslipidaemia in the MetS. Appropriate diagnostic criteria that include a modified definition of adiposity must be in place to facilitate the early detection and thus targeted treatment of increased risk in ethnic minorities.

Abnormal retinal vascular function and lipid levels in a sample of healthy UK South Asians

Background/aims To investigate ethnic differences in retinal vascular function and their relationship to traditional risk indicators for cardiovascular disease (CVD). Methods A total of 90 normoglycaemic subjects (45 South Asian (SA) and 45 age- and gender-matched white Europeans (WEs)) were recruited for the present study. Retinal vessel reactivity to flickering light was assessed by means of the dynamic retinal vessel analyser according to a modified protocol. Fasting plasma glucose, triglycerides (TG), total, LDL and HDL cholesterol were also measured in all individuals. Results SA individuals showed higher fasting triglyceride (p=0.001) and lower HDL levels (p=0.007), leading to a higher TG:HDL-C ratio (p=0.001) than age-matched WE subjects. Additionally, in SAs, the retinal arterial reaction time in response to flicker stimulation was significantly longer in the last flicker cycle than in the WEs (p=0.039), and this change correlated positively with measured plasma TG levels (r=0.60; p=0.01). No such relationship was observed in the WEs (p>0.05). Conclusion Even in the absence of overt vascular disease, in otherwise healthy SAs there are potential signs of retinal vascular function impairment that correlates with established plasma markers for CVD risk.

Premature cardiovascular events and mortality in south Asians with type 2 diabetes in the United Kingdom Asian Diabetes Study - effect of ethnicity on risk

Background/Aim - People of south Asian origin have an excessive risk of morbidity and mortality from cardiovascular disease. We examined the effect of ethnicity on known risk factors and analysed the risk of cardiovascular events and mortality in UK south Asian and white Europeans patients with type 2 diabetes over a 2 year period. Methods - A total of 1486 south Asian (SA) and 492 white European (WE) subjects with type 2 diabetes were recruited from 25 general practices in Coventry and Birmingham, UK. Baseline data included clinical history, anthropometry and measurements of traditional risk factors – blood pressure, total cholesterol, HbA1c. Multiple linear regression models were used to examine ethnicity differences in individual risk factors. Ten-year cardiovascular risk was estimated using the Framingham and UKPDS equations. All subjects were followed up for 2 years. Cardiovascular events (CVD) and mortality between the two groups were compared. Findings - Significant differences were noted in risk profiles between both groups. After adjustment for clustering and confounding a significant ethnicity effect remained only for higher HbA1c (0.50 [0.22 to 0.77]; P?=?0.0004) and lower HDL (-0.09 [-0.17 to -0.01]; P?=?0.0266). Baseline CVD history was predictive of CVD events during follow-up for SA (P?South Asian patients with type 2 diabetes in the UK have a higher cardiovascular risk and present with cardiovascular events at a significantly younger age than white Europeans. Enhanced and ethnicity specific targets and effective treatments are needed if these inequalities are to be reduced.

Prevalence and trends of the diabetes epidemic in South Asia : a systematic review and meta-analysis

Background Diabetes mellitus has reached epidemic proportions worldwide. South Asians are known to have an increased predisposition for diabetes which has become an important health concern in the region. We discuss the prevalence of pre-diabetes and diabetes in South Asia and explore the differential risk factors reported. Methods Prevalence data were obtained by searching the Medline® database with; ‘prediabetes’ and ‘diabetes mellitus’ (MeSH major topic) and ‘Epidemology/EP’ (MeSH subheading). Search limits were articles in English, between 01/01/1980–31/12/2011, on human adults (≥19 years). The conjunction of the above results was narrowed down with country names. Results The most recent reported prevalence of pre-diabetes:diabetes in regional countries were; Bangladesh–4.7%:8.5% (2004–2005;Rural), India–4.6%:12.5% (2007;Rural); Maldives–3.0%:3.7% (2004;National), Nepal–19.5%:9.5% (2007;Urban), Pakistan–3.0%:7.2% (2002;Rural), Sri Lanka–11.5%:10.3% (2005–2006;National). Urban populations demonstrated a higher prevalence of diabetes. An increasing trend in prevalence of diabetes was observed in urban/rural India and rural Sri Lanka. The diabetes epidemicity index decreased with the increasing prevalence of diabetes in respective countries. A high epidemicity index was seen in Sri Lanka (2005/2006–52.8%), while for other countries, the epidemicity index was comparatively low (rural India 2007–26.9%; urban India 2002/2005–31.3%, and urban Bangladesh–33.1%). Family history, urban residency, age, higher BMI, sedentary lifestyle, hypertension and waist-hip ratio were associated with an increased risks of diabetes. Conclusion A significant epidemic of diabetes is present in the South Asian region with a rapid increase in prevalence over the last two decades. Hence there is a need for urgent preventive and curative strategies .

Role of genetic polymorphism peroxisome proliferator-activated receptor-gamma2 Pro12Ala on ethnic susceptibility to diabetes in South-Asian and Caucasian subjects: Evidence for heterogeneity

OBJECTIVE: To determine whether the peroxisome proliferator-activated receptor (PPAR)-gamma Pro12ala polymorphism modulates susceptibility to diabetes in South Asians. RESEARCH DESIGN AND METHODS: South Asians (n = 697) and Caucasians (n = 457) living in Dallas/Forth Worth, Texas, and South Asians living in Chennai, India (n = 1,619), were enrolled for this study. PPAR-gamma Pro12Ala was determined using restriction fragment-length polymorphism. Insulin responsiveness to an oral glucose tolerance test (OGTT) was measured in nondiabetic subjects. RESULTS: The Caucasian diabetic subjects had significantly lower prevalence of PPAR-gamma 12Ala when compared with the Caucasian nondiabetic subjects (20 vs. 9%, P = 0.006). However, there were no significant differences between diabetic and nondiabetic subjects with reference to the Pro12Ala polymorphism among the South Asians living in Dallas (20 vs. 23%) and in India (19 vs. 19.3%). Although Caucasians carrying PPAR-gamma Pro12Ala had lower plasma insulin levels at 2 h of OGTT than the wild-type (Pro/Pro) carriers (76 +/- 68 and 54 +/- 33 microU/ml, respectively, P = 0.01), no differences in either fasting or 2-h plasma insulin concentrations were found between South Asians carrying the PPAR-gamma Pro12Ala polymorphism and those with the wild-type genotype at either Chennai or Dallas. CONCLUSIONS: Although further replication studies are necessary to test the validity of the described genotype-phenotype relationship, our study supports the hypothesis that the PPAR-gamma Pro12Ala polymorphism is protective against diabetes in Caucasians but not in South Asians.

Vascular dysfunction and reduced circulating endothelial progenitor cells in young healthy UK South Asian men

OBJECTIVES: The objective of this study was to examine determinants of excess coronary artery disease risk in UK South Asians, more prevalent in this population than UK Caucasians, by examining differences in risk factors, vascular function, and endothelial progenitor cells (EPCs). METHODS AND RESULTS: 24 South Asian and 25 Caucasian healthy age-matched nonsmoking men were studied. Vascular function was assessed by flow-mediated and GTN brachial artery dilatation and blood flow responses to infusion of ACh, SNP, and L-NMMA. EPC number and function were measured by flow cytometry (CD34, CD133, and KDR positive cells), and CFU/migration assays. Traditional risk factors and anthropometric measurements were similar in the groups. South Asians had higher fasting insulin levels (6.01 versus 3.62 microU/mL; P = 0.02). South Asians had lower FMD (6.9 versus 8.5%; P = 0.003), L-NMMA response (0.8 versus 1.3 mL/min/100 mL; P = 0.03), mean SNP response (9.5+/-0.6 versus 11.6+/-0.6; P = 0.02), EPC number (0.046+/-0.005% versus 0.085+/-0.009%; P = < 0.001), and CFU ability (CFU 4.29+/-1.57 versus 18.86+/-4.00; P = 0.005). EPC number was the strongest predictor of FMD. Ethnicity was the strongest predictor of EPC number. CONCLUSIONS: Healthy South Asian men are more insulin resistant, and demonstrate endothelial dysfunction and reduced EPC number and function compared with Caucasians. These abnormalities may contribute to their increased CAD risk.

South Asian immigrant cardiovascular risk assessment in Houston, Texas 2005

Background. Heart disease is the leading cause of death and stroke is the third leading cause of deaths for all people in the United States. South Asian Americans have a higher risk of developing cardiovascular diseases than native United States residents. ^ Purpose. This study examines the cardiovascular risk factors in the South Asian immigrant community residing in Southwest Houston. This study also explores the level of health insurance available to the South Asian in Houston. ^ Methods. One hundred sixty-two South Asian patients aged 18 years and older received cardiovascular screening from January 1 st, 2005 to March 31st, 2005 at Ibn Sina Community Clinic; blood pressure was measured twice in both arms after resting five minutes. Height and weight were also recorded. Demographic data was collected through personal interview (questionnaire) and blood samples were drawn to collect laboratory data. ^ Results. There were 162 eligible South Asian patients, among whom 127 (78%) participated in the study. There were no significant differences between the responders and the non-responders in terms of demographics and clinical characteristics. Laboratory data revealed a mean total cholesterol of 201 ± 34 mg/dl, 54 percent had high total cholesterol above 200 mg/dl. The mean fasting glucose was 108 ± 43 mg/dl, and body mass index (BMI) was 28 ± 4 kg/m2. The prevalence of hypertension was comparable with the general U.S. population; 38 percent of the South Asian males and 29 percent of females had hypertension. The prevalence of diabetes was also compared; 21 percent of SA males (3% for white American males) and 7 percent of SA females (2% for white American females) were found to have undiagnosed diabetes. Of the sample 12 percent had both hypertension and diabetes; 21 percent had both hypertension and high BMI, and 19 percent had hypertension and high total cholesterol levels. ^ Conclusion. The present study shows that the South Asians in this sample are at greater risk of developing cardiovascular diseases than other ethnicities. The high prevalence of hypertension, type 2 diabetes, higher total cholesterol levels with overweight and obesity, and less leisure time physical activity are important cardiovascular risk factors for South Asians population. ^

The experiences of South Asian university students in the British education system and in their search for work

This research aimed to provide a comparative analysis of South Asian and White British students in their academic attainment at school and university and in their search for employment. Data were gathered by using a variety of methodological techniques. Completed postal questionnaires were received from 301 South Asian and White British undergraduates from 12 British universities, who were in their final year of study in 1985. In depth interviews were also conducted with 49 graduates who were a self selected group from the original sample. Additional information was also collected by using diary report forms and by administering a second postal questionnaire to selected South Asian and White British participants. It was found that while the pre-university qualifications of the White British and South Asian undergraduates did not differ considerably, many members in the latter group had travelled a more arduous path to academic success. For some South Asians, school experiences included the confrontation of racist attitudes and behaviour, both from teachers and peers. The South Asian respondents in this study were more likely than their White British counterparts, to have attempted some C.S.E. examinations, obtained some of their `O' levels in the Sixth Form and retaken their `A' levels. As a result the South Asians were on average older than their White British peers when entering university. A small sample of South Asians also found that the effects of racism were perpetuated in higher education where they faced difficulty both academically and socially. Overall, however, since going to university most South Asians felt further drawn towards their `cultural background', this often being their own unique view of `Asianess'. Regarding their plans after graduation, it was found that South Asians were more likely to opt for further study, believing that they needed to be better qualified than their White British counterparts. For those South Asians who were searching for work, it was noted that they were better qualified, willing to accept a lower minimum salary, had made more job applications and had started searching for work earlier than the comparable White British participants. Also, although generally they were not having difficulty in obtaining interviews, South Asian applicants were less likely to receive an offer of employment. In the final analysis examining their future plans, it was found that a large proportion of South Asian graduates were aspiring towards self employment.

Telomere length attrition, a marker of biological senescence, is inversely correlated with triglycerides and cholesterol in South Asian males with type 2 diabetes mellitus

South Asians have a higher risk of type 2 diabetes mellitus (T2DM) and cardiovascular disease (CVD) than white Caucasians, for a given BMI. Premature biological ageing, assessed by reduction in telomere length (TL), may be mediated by factors resulting from altered metabolic profiles associated with obesity. We hypothesise that ethnicity and metabolic status represent detrimental factors contributing to premature biological ageing. Therefore we assessed TL in two South Asian, age and BMI-matched cohorts [T2DM (n = 142) versus non-T2DM (n = 76)] to determine the effects of BMI, gender, lipid and CVD profile on biological ageing. Genomic DNA was obtained from the UKADS cohort; biochemical and anthropometric data was collected and TL was measured by quantitative real-time PCR. Our findings indicated a gender-specific effect with reduced TL in T2DM men compared with non-T2DM men (P = 0.006). Additionally, in T2DM men, TL was inversely correlated with triglycerides and total cholesterol (r = -0.419, P <0.01; r = -0.443, P <0.01). In summary, TL was reduced amongst South Asian T2DM men and correlated with triglycerides and total cholesterol. This study highlights enhanced biological ageing among South Asian, T2DM men, which appears to be tracked by changes in lipids and BMI, suggesting that raised lipids and BMI may directly contribute to premature ageing.

An FTO variant is associated with Type 2 diabetes in South Asian populations after accounting for body mass index and waist circumference

Aims - A common variant, rs9939609, in the FTO (fat mass and obesity) gene is associated with adiposity in Europeans, explaining its relationship with diabetes. However, data are inconsistent in South Asians. Our aim was to investigate the association of the FTO rs9939609 variant with obesity, obesity-related traits and Type 2 diabetes in South Asian individuals, and to use meta-analyses to attempt to clarify to what extent BMI influences the association of FTO variants with diabetes in South Asians. Methods - We analysed rs9939609 in two studies of Pakistani individuals: 1666 adults aged = 40 years from the Karachi population-based Control of Blood Pressure and Risk Attenuation (COBRA) study and 2745 individuals of Punjabi ancestry who were part of a Type 2 diabetes case–control study (UK Asian Diabetes Study/Diabetes Genetics in Pakistan; UKADS/DGP). The main outcomes were BMI, waist circumference and diabetes. Regression analyses were performed to determine associations between FTO alleles and outcomes. Summary estimates were combined in a meta-analysis of 8091 South Asian individuals (3919 patients with Type 2 diabetes and 4172 control subjects), including those from two previous studies. Results - In the 4411 Pakistani individuals from this study, the age-, sex- and diabetes-adjusted association of FTO variant rs9939609 with BMI was 0.45 (95% CI 0.24–0.67) kg/m2 per A-allele (P = 3.0 × 10-5) and with waist circumference was 0.88 (95% CI 0.36–1.41) cm per A-allele (P = 0.001). The A-allele (30% frequency) was also significantly associated with Type 2 diabetes [per A-allele odds ratio (95% CI) 1.18 (1.07–1.30); P = 0.0009]. A meta-analysis of four South Asian studies with 8091 subjects showed that the FTO A-allele predisposes to Type 2 diabetes [1.22 (95% CI 1.14–1.31); P = 1.07 × 10-8] even after adjusting for BMI [1.18 (95% CI 1.10–1.27); P = 1.02 × 10-5] or waist circumference [1.18 (95% CI 1.10–1.27); P = 3.97 × 10-5]. Conclusions - The strong association between FTO genotype and BMI and waist circumference in South Asians is similar to that observed in Europeans. In contrast, the strong association of FTO genotype with diabetes is only partly accounted for by BMI.

The promoter polymorphism -232C/G of the PCK1 gene is associated with type 2 diabetes in a UK-resident South Asian population

Background - The PCK1 gene, encoding cytosolic phosphoenolpyruvate carboxykinase (PEPCKC), has previously been implicated as a candidate gene for type 2 diabetes (T2D) susceptibility. Rodent models demonstrate that over-expression of Pck1 can result in T2D development and a single nucleotide polymorphism (SNP) in the promoter region of human PCK1 (-232C/G) has exhibited significant association with the disease in several cohorts. Within the UK-resident South Asian population, T2D is 4 to 6 times more common than in indigenous white Caucasians. Despite this, few studies have reported on the genetic susceptibility to T2D in this ethnic group and none of these has investigated the possible effect of PCK1 variants. We therefore aimed to investigate the association between common variants of the PCK1 gene and T2D in a UK-resident South Asian population of Punjabi ancestry, originating predominantly from the Mirpur area of Azad Kashmir, Pakistan. Methods - We used TaqMan assays to genotype five tagSNPs covering the PCK1 gene, including the -232C/G variant, in 903 subjects with T2D and 471 normoglycaemic controls. Results - Of the variants studied, only the minor allele (G) of the -232C/G SNP demonstrated a significant association with T2D, displaying an OR of 1.21 (95% CI: 1.03 - 1.42, p = 0.019). Conclusion - This study is the first to investigate the association between variants of the PCK1 gene and T2D in South Asians. Our results suggest that the -232C/G promoter polymorphism confers susceptibility to T2D in this ethnic group.

Macular pigment optical density in young adults of South Asian origin

Purpose: To assess the range of macular pigment optical density (MPOD) in a healthy group of young adults of South Asian origin; to investigate whether any dietary factors or personal characteristics were related to inter-subject variations in MPOD; and to compare the mean MPOD of the South Asian group with the mean MPOD of a white group. Methods: Heterochromatic flicker photometry was used to measure the MP levels of 169 healthy volunteers, of which 117 were Asian and 52 were white. In addition, the Asian participants completed a questionnaire pertaining to the various physical, ocular, lifestyle, dietary and environmental factors that may be associated with MPOD or age-related macular degeneration (AMD). Results: The mean MPOD of the Asian subjects was 0.43±0.14. The male participants had a higher mean MPOD than the females (0.47±0.13 vs 0.41±0.14, p<0.01). Possible associations also emerged between MPOD and form of refractive correction, and iris colour. No MPOD associations were found for the other variables examined in the questionnaire. The mean MPOD of the white subject group was 0.33±0.13, which was significantly lower than the Asian group (p<0.0005). Conclusions: This study adds to the currently limited information on MPOD in South Asians, and while a comparison between Asians and Whites was not the main focus here, highly significant differences between these two ethnicities were revealed. This provokes the possibility that South Asian individuals could have a lower risk for AMD, and it warrants further study.