Subclinical atherosclerosis and silent myocardial ischaemia in patients with type 2 diabetes: a protocol of a clinico-observational study

Prevalence and RIsk factors for Silent Myocardial ischemia (PRISM): A clinico observational study in patients of type 2 diabetes

Objectives

To estimate the prevalence and to identify potential risk factors of silent myocardial ischemia in a cohort of patients with asymptomatic type 2 Diabetes (diabetes) for early detection of coronary risk by employing objective noninvasive clinical screening tools for Subclinical Atherosclerosis.

Methods

The study is a clinic-based observational study on 338 consecutive diabetes patients attending an urban health center from Eastern India. The response rate was 96.57% out of 350 eligible subjects, comprising 176 (52.1%) males and 162 (47.9%) females. Clinical, anthropometric, biochemical parameters were collected in all participants. Both tools, i.e., treadmill test (TMT) to identify subjects with silent myocardial ischemia, and carotid imaging to detect subclinical atherosclerosis by evaluating carotid intima-media thickness (CIMT), were assessed. Significant determinants were predicted by multivariable logistic regression.

Results

The study group was divided into a TMT negative (n = 260), and a TMT positive group (n = 78). These 78 TMT positive subjects (23.1%) were identified to have silent myocardial ischemia. The prevalence of silent myocardial ischemia was more common in males (28.4%) than in females (17.3%). The mean CIMT in our study group was 0.6741 ± 0.034 mm (males – 0.684 ± 0.034 mm and females – 0.663 ± 0.032 mm). Age ≥50 years, CIMT ≥0.70 mm, hypercholesterolemia, and hypertriglyceridemia were significant determinants for identifying asymptomatic diabetics at risk for silent myocardial ischemia.

Conclusion

Silent myocardial ischemia is highly prevalent at about one in four asymptomatic diabetic patients. An increased CIMT can be a surrogate marker of higher coronary risk amongst these asymptomatic diabetics.

Chronic administration of antioxidant resin from Virola oleifera attenuates atherogenesis in LDLr -/- mice

ETHNOPHARMACOLOGICAL RELEVANCE

Virola oleifera (Schott) A. C. Smith, Myristicaceae has been largely used in traditional folk medicine in Brazil as an anti-inflammatory agent and our previous data indicated the antioxidant properties in other oxidative stress-related models. However, its effects on atherosclerosis (AT) are not yet investigated.

AIMS OF THE STUDY

To evaluate the influence of resin from Virola oleifera (RV) on progression of AT in LDLr^-/- mice.

MATERIALS AND METHODS

LDLr^-/- mice were divided into 4 groups: 1) The ND group received a normal diet without treatment. 2) The HD group received a high-fat diet without treatment. 3) The HD-V50 received a high-fat diet and was orally treated with RV at 50mg/Kg. 4) The HD-V300 received a high-fat diet and was orally treated with RV at 300mg/Kg. After 4 weeks, blood was collected to quantify biochemical parameters and ROS total and the aorta was removed to measure the lipid deposition by en face analysis. The liver was also collected to determine total lipids and lipid and protein oxidation. In order to investigate in more detail the contributions of RV in the vascular structure, we carried out the in vitro tests using four cellular types: macrophages, fibroblasts, vascular smooth muscle and endothelial cells.

RESULTS

We showed that the chronic treatment of RV at both doses reduced vascular lipid accumulation (~50%, p<0.05), probably through systemic and hepatic antioxidant effects, independent of dyslipidemia. Moreover, the in vitro assay results demonstrated that RV develops antioxidant properties on the vascular smooth muscle and endothelial cells, reinforcing the protective role of RV in progression of AT. LPS-stimulated macrophages treated with RV resulted in a significant reduction of NO production in a concentration-dependent manner.

CONCLUSIONS

Chronic treatment with RV diminishes lipid deposition in atherosclerotic mice, which may be justified, at least in part, by antioxidant systemic and local mechanisms, reinforcing the protective role this resin in the setting of vascular lipid deposition, independent of hypercholesterolemia.

Erectile dysfunction and its management in patients with diabetes mellitus

Diabetes can be described as a syndrome of multiple closely related conditions induced by a chronic state of hyperglycaemia resulting from defective insulin secretion, insulin action or both. Chronic complications associated with diabetes (including neuropathy, vascular disease, nephropathy and retinopathy) are common, and of these, erectile dysfunction (ED) deserves special attention. ED and its correlation with cardiovascular disease require careful evaluation and appropriate treatment. PDE5 inhibitors (PDE5is) are an important tool for the treatment of ED, with new drugs coming onto the market since the late 90s. This review offers an overview of PDE5is and their use in treating ED in diabetes. We underline the differences between different types of PDE5i, focusing on available doses, duration of action, T ½, side effects and selectivity profiles in relation to patients with diabetes. We also discuss the link between diabetes and ED in presence of various associated cofactors (obesity, hypertension and its pharmacological treatments, atherosclerosis, hyperhomocysteinaemia, neuropathy, nephropathy, hypogonadism and depression). Finally a number of past and ongoing clinical trials on the use of PDE5is in patients with diabetes are presented to offer an overview of the appropriate treatment of ED in this condition.