Diabetes mellitus as a risk factor for acute myocardial infarction in Asians and Europeans

Expression and function of lncRNA ANRIL in a mouse model of acute myocardial infarction combined with type 2 diabetes mellitus

BACKGROUND

This study intends to explore whether lncRNA ANRIL has an influence on type 2 diabetes mellitus (T2DM) complicated with acute myocardial infarction (MI) and to further investigate the underlying mechanism.

METHODS

The ANRIL level in peripheral blood from patients was detected by qRT-PCR. A T2DM mouse model was established by intraperitoneal injection of streptozocin (STZ). MI was induced by ligation of the left anterior descending coronary artery. Cardiac function parameters were measured using echocardiography. Triphenyltetrazolium chloride (TTC) staining was performed to determine the infarct size, and Masson staining was conducted to delineate the area of fibrosis in the myocardium. TUNEL staining was used to detect myocardial cell apoptosis. The expression of the myocardial fibrosis-related proteins TGF-β1, collagen I and collagen III was analysed using Western blot.

RESULTS

ANRIL was upregulated in peripheral venous blood from patients with T2DM-MI and in myocardial tissues from the established T2DM-MI model mice. Furthermore, ANRIL overexpression caused cardiac dysfunction and increased the heart/body weight rate and infarct size in the T2DM-MI mice. Moreover, ANRIL overexpression caused myocardial fibrosis and myocardial cell apoptosis, and it increased the expression of the myocardial fibrosis-related proteins TGF-β1, collagen I and collagen III in the T2DM-MI mice. However, ANRIL knockdown exerted the opposite effects.

CONCLUSION

ANRIL may be involved in the progression and development of T2DM-MI, which might provide novel ideas for the prevention and treatment of cardiovascular diseases.

Determination of risk factors affecting the in-hospital prognosis of patients with acute ST segment elevation myocardial infarction after percutaneous coronary intervention

BACKGROUND

To determine the factors affecting the in-hospital prognosis of patients with acute ST segment elevation myocardial infarction (STEMI) after percutaneous coronary intervention (PCI), and to establish its prognostic discriminant model.

METHODS

A total of 701 consecutive STEMI patients undergoing PCI were enrolled in this study. The patients were divided into two groups, good prognosis and poor prognosis, based on whether the patient had adverse outcomes (death or heart function ≥ grade III) at discharge. Demographic and basic clinical characteristics, diagnosis at admission (e.g., ventricular function, complications, or hyperlipidemia), and biomedical indicators (e.g., blood count, basal metabolism and biochemical composition, blood lipid and glucose levels, myocardial biomarkers, and coagulation) were collected and analyzed.

RESULTS

We determined 22 factors as risk factors for the in-hospital prognosis of STEMI patients after PCI: age, cardiac function during hospitalization, complications, history of diabetes mellitus, et al., among which the history of diabetes, uric acid, urea nitrogen, and activated partial thromboplastin time (APTT) were independent risk factors.

CONCLUSION

We identified four independent risk factors for the in-hospital prognosis of STEMI patients after PCI and generated a prognostic model to predict the adverse outcomes of these patients.

A clinical scoring system in undifferentiated chest pain predicting undetectable troponin concentration

BACKGROUND

Chest pain is the most common reason for emergency admission to hospital, but the majority of these are due to non-cardiac pain. We sought to determine which combination of clinical features is more likely to predict an undetectable troponin level in patients presenting with chest pain.

METHODS

We collected data over a two-month period on consecutive patients presenting acutely to hospital with chest pain and who had a troponin I measured. We recorded basic demographics, risk factors, pain distribution, associated symptoms, physical findings and ECG changes. The parameters significantly associated with troponin positivity were entered into a stepwise logistic regression analysis and the resulting model's coefficients were used to construct a simple clinical score to categorise patients into low, medium or high probability of having a positive troponin.

RESULTS

26 of 157 (16.6%) patients had a positive troponin. The variables retained in the regression model were: age >65, heart rate >80, previous myocardial infarction, diabetes and pain radiating to either arm. The model showed good discrimination (area under ROC curve 0.869, 95% CI 0.806 - 0.917). Using the regression model's coefficients, patients were grouped into low, intermediate or high probability groups. Being in the low probability group had a negative predictive value of 97.8% and being in the high probability group had a positive predictive value of 65.2%. The majority (73.9%) of patients could be categorised as either low or high probability.

DISCUSSION

This simple scoring system, if prospectively validated, may be useful in identifying low risk patients with chest pain who are unlikely to have elevation of serum troponin concentration.

More than skin deep: atherosclerosis as a systemic manifestation of psoriasis

There is now growing evidence that psoriasis, like other inflammatory diseases such as rheumatoid arthritis and systemic lupus erythematosus, is a systemic disorder that is associated with enhanced atherosclerosis and risk of coronary artery disease. Here we summarize the available epidemiological evidence for this association and analyse pathogenic features that are common to psoriasis and atherosclerosis. Further prospective studies are urgently needed to extend knowledge of the risk of cardiovascular morbidity and mortality in patients with psoriasis and to confirm the degree to which treatment of psoriasis reduces this risk. Nevertheless, existing data are sufficient to indicate that severe psoriasis should be more widely recognized as a potential risk factor for cardiovascular disease and should be considered with the established factors when formulating strategies for the management of cardiovascular risk.

The epidemiology of central fat distribution in relation to disease

The effect of fat distribution on disease risk is a subject of great interest. Central fat has been measured anthropometrically, by computed tomography, and by magnetic resonance imaging. Both cross-sectional and longitudinal studies have related central fat to type 2 diabetes mellitus and cardiovascular disease, independent of body mass index. The mechanism may relate to increased lipolysis causing the liver to increase glucose and very low density lipoprotein output, while muscle uses less. This leads to a rise in blood glucose and triglycerides, a drop in HDL cholesterol, and an increase in small, dense LDL particles. There is also an increase in blood pressure and inflammatory markers. Certain populations put on excess fat more centrally than others. These include Asian populations. It is likely that with better differentiation of abdominal fat into visceral and subcutaneous depots, clearer data will accrue on their impact on disease risk.

Mortality of South Asian patients with insulin-treated diabetes mellitus in the United Kingdom: a cohort study

AIMS

To investigate mortality in South Asian patients with insulin-treated diabetes and compare it with mortality in non South Asian patients and in the general population.

METHODS

A prospective cohort study was conducted of 828 South Asian and 27 962 non South Asian patients in the UK with insulin-treated diabetes diagnosed at ages under 50 years. The patients were followed for up to 28 years. Ethnicity was determined by analysis of names. Standardized mortality ratios (SMRs) were calculated, comparing mortality in the cohort with expectations from the mortality experience of the general population.

RESULTS

SMRs were significantly raised in both groups of patients, particularly the South Asians, and especially in women and subjects with diabetes onset at a young age. The SMRs for South Asian patients diagnosed under age 30 years were 3.9 (95% CI 2.0-6.9) in men and 10.1 (5.6-16.6) in women, and in the corresponding non South Asians were 2.7 (2.6-2.9) and 4.0 (3.6-4.3), respectively. The SMR in women was highly significantly greater in South Asians than non South Asians. The mortality in the young-onset patients was due to several causes, while that in the patients diagnosed at ages 30-49 was largely due to cardiovascular disease, which accounted for 70% of deaths in South Asian males and 73% in females.

CONCLUSIONS

South Asian patients with insulin-treated diabetes suffer an exceptionally high mortality. Clarification of the full reasons for this mortality are needed, as are measures to reduce levels of known cardiovascular disease risk factors in these patients.

Diabetes mellitus and coronary heart disease

Diabetes mellitus, especially type 2 diabetes, is a growing concern in America. Longitudinal trends show that obesity is more prevalent than in the past, and the incidence of type 2 diabetes is also increasing. Type 2 diabetes typically doubles the CHD risk in men and triples the risk in women. Intervening to control lipid levels and blood pressure has been shown to be especially helpful in preventing CHD, but the impact of better glycemic control on CHD risk is less convincing, especially in clinical trials. Revascularization studies in diabetics show that coronary bypass surgery is related to better outcomes than angioplasty procedures.

The plasma levels of dehydroepiandrosterone sulfate are decreased in patients with chronic heart failure in proportion to the severity

Dehydroepiandrosterone sulfate (DHEAS) is the major secretory steroid of the human adrenal glands. The secretion of DHEAS decreases with aging. The incidence of heart failure also rises in the elderly population. We measured the plasma levels of DHEAS and cortisol in 49 patients with chronic heart failure (CHF) and 32 age-matched controls and assessed its relation to plasma levels of A-type natriuretic peptide and B-type natriuretic peptide, biochemical markers of heart failure. Plasma levels of DHEAS were significantly lower in patients with CHF than in controls, whereas there was no significant difference in plasma levels of cortisol between the two groups. In stepwise regression analysis, the plasma level of DHEAS was significantly and independently correlated with age (beta = -0.451; P < 0.0001) and the plasma level of B-type natriuretic peptide (beta = -0.338; P < 0.001), and the plasma cortisol/DHEAS ratio was significantly and independently correlated with the plasma levels of A-type natriuretic peptide (beta = 0.598; P < 0.0001) and thiobarbituric acid-reactive substances (a marker of oxidative stress; beta = 0.252; P < 0.01) and age (beta = 0.171; P < 0.05). These results indicate that the plasma levels of DHEAS are decreased in patients with CHF in proportion to its severity and that oxidative stress is associated with decreased levels of DHEAS in patients with CHF.

Computed tomography-determined body composition in relation to cardiovascular risk factors in Indian and matched Swedish males

Relationships between cardiovascular risk factors, body composition, and tissue distributions were examined in 10 Indian and 10 Swedish males matched by age, height, and weight. The body was divided into 29 compartments by means of a multiscan computed tomography (CT) technique. Fasting glucose, insulin, and triglycerides (TG) were higher in Indians than in Swedes. During the oral glucose tolerance test (OGTT), the glucose area was similar in both groups, whereas the insulin area was 80% larger in Indians. Adipose tissue (AT) and skin volumes were larger and remaining lean tissues were smaller in Indians. Indians had proportionally less muscle and more skeleton in the legs, but no ethnic difference could be demonstrated with respect to AT distribution. The visceral AT to total AT volume ratio was positively related to insulin and TG, and with higher risk factors for Indians at any given ratio. TG and glucose were negatively related to the leg muscle to total muscle volume ratio, and this ratio was smaller in Indians. It is concluded that the metabolic disturbances of Indians are not necessarily dependent on a preponderance of visceral AT, and also that an upper-body muscle distribution-recognized as a new phenotypic companion to the metabolic syndrome-is statistically related to cardiovascular risk factors.

Platelets from patients with diabetes mellitus have impaired ability to mediate vasodilation

OBJECTIVES

The purpose of this study was to examine vasomotor responses mediated by platelets from patients with diabetes mellitus.

BACKGROUND

Diabetes mellitus is associated with increased cardiovascular morbidity and mortality, which in part may be due to a variety of abnormalities reported in diabetic platelets. However, the effects of diabetic platelets on vasomotor tone have not been characterized.

METHODS

We compared platelet-mediated vasodilation elicited by platelets isolated from 30 healthy volunteers and 29 patients with diabetes mellitus as they were perfused through a preconstricted normal rabbit carotid artery.

RESULTS

Platelets from the diabetic patients mediated an impaired dilatory response in comparison with normal platelets: 2.7 +/- 2% versus 15.8 +/- 3.4% (p < 0.001) and 4.1 +/- 2.7% versus 32.7 +/- 3.3% (p < 0.001) (mean +/- SEM) increase in vessel diameter, for 5 X 10(7) and 1 X 10(8) platelets per milliliter perfused, respectively. The degree of impairment was similar for type I (insulin-dependent) and type II (non-insulin-dependent) diabetes mellitus. Normal platelets incubated in high D-glucose concentrations lost their ability to mediate dilation in a concentration-dependent and time-dependent manner. This was not true for incubation of normal platelets in high concentrations of L-glucose or insulin. However, there was not a significant correlation between glucose control in the diabetic patients and the ability of their platelets to mediate vasodilation.

CONCLUSIONS

Platelets from patients with diabetes mellitus have an impaired ability to mediate vasodilation. This impairment appears to be mediated by high glucose concentration. Further work is needed to elucidate the mechanisms for this abnormality in diabetic platelets.

Diabetes care in South Asian and white European patients with type 2 diabetes

Aspects of diabetes care in South Asian and white European patients with Type 2 diabetes attending a hospital review clinic were explored. Among the clinic population of 1710 patients, 258 (15%) were of South Asian origin. A significantly greater proportion (95% CI for difference in proportions 8-22%) of these patients was treated with oral hypoglycaemic drugs than in white Europeans, in whom there was a correspondingly greater proportion receiving insulin treatment. In a case-control study, where 154 patients in each racial group were stratified according to treatment regimen, significantly more South Asian patients (13/30 vs 6/30, p < 0.05) on insulin were treated with a once-daily regimen. Despite these observed differences in treatment of diabetes, glycaemic control was no worse in South Asian patients when compared to their white European counterparts. South Asian diabetic patients attending hospital diabetes clinics in the UK can experience similar levels of glycaemic control to white Europeans.

Does a history of hypertension influence the prognosis among diabetics with acute chest pain?

The purpose of this study was to relate the 1-year risk of death and development of acute myocardial infarction among diabetics with acute chest pain to whether they had a history of hypertension or not. All patients with a history of diabetes mellitus who, during 21 months, were admitted to the Emergency Room in Sahlgrenska Hospital, Göteborg, due to chest pain or other symptoms suggestive of acute myocardial infarction, were included. Among the 427 patients with a history of diabetes mellitus 44% also had a history of hypertension. These hypertensives had a 1-year mortality rate of 22% as compared with 26% in diabetics without such a history (p > 0.2). The corresponding values for development of myocardial infarction during 1 year were 33 and 30%, respectively (p > 0.2). We did not find a history of hypertension to adversely affect the prognosis among diabetics with acute chest pain.

Natural micronutrients as controlling factors in Western diseases--a lesson in nature-programming

Micronutrients, essential for approximately 65% of all known enzymes, have during this century been considerably reduced in modern Western diets, due to food refinement, canning, refrigeration and additives. This reduction coincided with a phenomenal increase of Western and industrial diseases, many of them with genetic associations. Different basic diets in genetic races over thousands of years have led to a high percentage of enzyme polymorphisms, suggesting different basic diets necessary for different genetic races. These basic diets, with or without micronutrient supplementation, should be a necessary component of Western diseases prevention and therapy.

The prevalence of macrovascular disease and lipid abnormalities amongst diabetic patients in Sri Lanka

The prevalence of macrovascular disease and hyperlipidaemia was examined in 500 patients with non-insulin-dependent diabetes mellitus attending a diabetic clinic in a Sri Lankan teaching hospital and 250 controls matched for age and gender. Macrovascular disease was assessed using a modified World Health Organisation questionnaire and modified Minnesota coding of electrocardiogram recordings. Twenty-one per cent of diabetic patients and 14.3% of controls had hypercholesterolaemia (P < 0.05). Macrovascular disease was present in 13.4% of diabetic patients and 8.2% of controls. Significant differences were seen in the prevalence of hypertension (15.6% vs 4.8%, P < 0.05), obesity (16.2% vs 9.7%, P < 0.05), peripheral vascular disease (5.6% vs 2%, P < 0.05) and electrocardiographic abnormalities (12% vs 6%, P < 0.05) in diabetic patients when compared to controls. Hyperlipidaemia and macrovascular disease is common in non-insulin-dependent diabetic patients in Sri Lanka and accounts for significant morbidity.

Central rather than generalized obesity is related to hyperglycaemia in Asian Indian subjects

The relationship of body mass index and waist-hip ratio with plasma glucose concentrations during an oral glucose tolerance test (OGTT) was studied in native Indian (Asian) subjects. A total of 389 subjects (131 non-diabetic, 74 impaired glucose tolerant (IGT) and 184 Type 2 diabetic (newly diagnosed and untreated] were studied. Prevalence of obesity (BMI greater than or equal to 27.0 kg m-2 in men and greater than or equal to 25.0 kg m-2 in women, 21% and 47%, respectively) was lower in people with Type 2 diabetes than that reported in white Caucasian and migrant Asian populations. Body mass index was highest in IGT subjects (26.1 (19.7-34.3) kg m-2, median (5-95th centile] and was higher in diabetic subjects (24.2 (19.3-32.2) kg m-2) than in non-diabetic control subjects (23.5 (17.1-30.0) kg m-2). However, waist-hip ratio was higher in both IGT (0.88 (0.75-0.98)) and diabetic subjects (0.88 (0.75-1.00)) than in non-diabetic control subjects (0.83 (0.70-0.97)), with no difference between the hyperglycaemic groups. On multivariate analysis, fasting as well as 2-h plasma glucose concentrations during OGTT were found to be related to waist-hip ratio (p less than 0.01) and subscapular fat thickness (p less than 0.01) but not to body mass index (or triceps fat thickness). Thus, in native Indians central obesity seems to be a more important association of hyperglycaemia than generalized obesity.