cardiovascular-agents and Diabetic-Retinopathy

Inhibitors of the renin angiotensin aldosterone system (RAAS) represent some of the most widely prescribed, successful and well-tolerated therapeutics of recent times and are of proven worth in the management/prevention of cardiovascular disease and diabetic nephropathy. However, as knowledge has grown about the RAAS and its manifold alternate pathways, loci of action and dynamic response to inhibition, so has the clinical debate as how to best use existing therapeutics as well as how best to conceptualise and design RAAS inhibitors of the future.. To provide an overview of the several points of therapeutic anti-RAAS intervention, many of which have already been exploited from 'upstream' renin inhibition to 'midstream' ACE inhibition to 'downstream' angiotensin AT1 receptor blockade.. A search of patents for RAAS inhibitors recorded in 2008 was conducted along with a relevant literature search.. Each intervention has merits and demerits with implications for RAAS 'escape' phenomena, 'dual inhibition' therapy, long-term clinical efficacy and adverse drug reactions. Renin inhibitors offer the most complete RAAS inhibition, but more downstream interventions are likely to recruit supplementary anti-RAAS mediators and receptor signalling pathways. Furthermore, managing hyperkalaemia-stimulated aldosterone escape during combined ACE inhibitor and angiotensin receptor blocker treatment may realise the full clinical potential of dual inhibition therapy.

Topics: Cardiovascular Agents; Cardiovascular Diseases; Diabetic Retinopathy; Drug Delivery Systems; Drug Design; Humans; Patents as Topic; Renin-Angiotensin System

Most of the late diabetic complications such as retinopathy, nephropathy, and neuropathy, have their basis in disturbed microvascular function. Structural and functional changes in the micro-circulation are present in diabetes mellitus irrespective of the organ studied, and the pathogenesis is complex. Endothelial dysfunction, characterized by an imbalance between endothelium-derived vasodilator and vasoconstrictor substances, plays an important role in the pathogenesis of diabetic microangiopathy. Increased circulating levels of endothelin-1 (ET-1), a potent vasoconstrictor peptide, has been found in patients with diabetes, and a positive correlation between plasma ET-1 levels and microangiopathy in patients with type 2 diabetes has been demonstrated. In addition to its direct vasoconstrictor effects, enhanced levels of ET-1 may contribute to endothelial dysfunction through inhibitory effects on nitric oxide (NO) production. Vascular endothelial dysfunction may precede insulin resistance, although the feature of insulin resistance syndrome includes factors that have negative effects on endothelial function. Furthermore, ET-1 induces a reduction in insulin sensitivity and may take part in the development of the metabolic syndrome. In the following, the mechanisms by which ET-1 contributes to the development of diabetic microangiopathy and the potentially beneficial effect of selective ET(A) receptor antagonists are discussed.

Topics: Cardiovascular Agents; Diabetic Angiopathies; Diabetic Nephropathies; Diabetic Neuropathies; Diabetic Retinopathy; Endothelin Receptor Antagonists; Endothelin-1; Humans; Microcirculation; Receptors, Endothelin; Treatment Outcome; Up-Regulation

Stroke is an important cause of morbidity and mortality, and is an economic burden. Diabetes and obesity are two important modifiable risk factors for stroke. Patients with diabetes have a higher incidence of stroke and a poorer prognosis after stroke. Risk-factor modification is the most important aspect of prevention of stroke in diabetes and obesity. This includes lifestyle modifications and different therapeutic modalities to control conditions, such as diabetes, hypertension, dyslipidemia and arrhythmia. Recent landmark studies have shown the beneficial effects of statins in diabetic patients even with close to normal or normal low-density lipoprotein cholesterol. Obesity, which is a risk factor for diabetes, hypertension and hyperlipidemia has been shown to be an independent risk factor for stroke. Increased leptin, dysregulation of adipocyte proteins, increased insulin resistance and C-reactive protein may be factors involved in the increased incidence of cardiovascular morbidity and mortality directly related to obesity. Visceral fat is a much bigger health risk than subcutaneous fat. Lifestyle interventions and pharmacotherapeutic agents have been used to manage obesity. In morbidly obese patients, surgical intervention seems to be the best method of treatment with a long-lasting favorable metabolic outcome. In the 21st Century, with the advanced medical knowledge and the therapeutic modalities available, it should be possible to reduce the incidence of stroke associated with diabetes and obesity.

Topics: Anti-Inflammatory Agents, Non-Steroidal; Aspirin; Atrial Fibrillation; Blood Glucose; Cardiovascular Agents; Carotid Stenosis; Diabetes Mellitus; Diabetic Angiopathies; Diabetic Nephropathies; Diabetic Retinopathy; Dyslipidemias; Humans; Hypertension; Insulin Resistance; Ischemic Attack, Transient; Leptin; Life Style; Lipoproteins; Obesity; Plasminogen Activator Inhibitor 1; Risk Factors; Smoking; Stroke

Diabetic retinopathy (DR) is the most common microvascular complication of diabetes. Diabetic macroangiopathies, particularly cardiovascular (CV) diseases, seem closely related to diabetes microvascular complications. Aspirin represents the most prescribed compound in CV prevention. Aspirin impact on DR is still object of debate. As it is already recommended among diabetics at high CV risk, aim of this study was to assess a potential relationship between DR and aspirin therapy, in a type 2 diabetes cohort of patients screened through telemedicine.. NO Blind is a cross-sectional, multicenter, observational study, which involved nine Italian outpatient clinics. Primary endpoint was the assessment of the relationship between aspirin treatment and DR. 2068 patients were enrolled in the study, subsequently split in two subpopulations according to either the presence or absence of DR. Overall, 995 subjects were under aspirin therapy. After adjusting for most common potential confounders, age and gender, aspirin reveals significantly associated with DR (OR: 1.72, 95%CI: 1.58-2.89, p = 0.002) and proliferative DR (PDR) (OR: 1.89, 95%CI: 1.24-2.84, p = 0.003). Association comes lost further adjusting for MACEs (OR: 1.28, 95%CI: 0.85-1.42, p = 0.157) (Model 4) and eGFR (OR: 0.93; 95%CI: 0.71-1.22; p = 0.591) (Model 5).. In this multicenter cross-sectional study including a large sample of outpatients with T2DM, we showed that aspirin was not associated with DR after adjustment for several cardio-metabolic confounders. However, as partially confirmed by our findings, and related to the well-known pro-hemorrhagic effect of aspirin, its use should be individually tailored, even by telemedicine tools.

Topics: Aged; Aspirin; Cardiovascular Agents; Cardiovascular Diseases; Cross-Sectional Studies; Diabetes Mellitus, Type 2; Diabetic Retinopathy; Female; Humans; Italy; Male; Middle Aged; Risk Assessment; Risk Factors; Time Factors; Treatment Outcome

Previously, we had shown that a vasopeptidase inhibitor drug containing ACE and neprilysin inhibitors was an effective treatment for diabetic vascular and neural complications. However, side effects prevented further development. This led to the development of sacubitril/valsartan, a drug containing angiotensin II receptor blocker and neprilysin inhibitor that we hypothesized would be an effective treatment for diabetic peripheral neuropathy. Using early and late intervention protocols (4 and 12 weeks posthyperglycemia, respectively), type 2 diabetic rats were treated with valsartan or sacubitril/valsartan for 12 weeks followed by an extensive evaluation of vascular and neural end points. The results demonstrated efficacy of sacubitril/valsartan in improving vascular and neural function was superior to valsartan alone. In the early intervention protocol, sacubitril/valsartan treatment was found to slow progression of these deficits and, with late intervention treatment, was found to stimulate restoration of vascular reactivity, motor and sensory nerve conduction velocities, and sensitivity/regeneration of sensory nerves of the skin and cornea in a rat model of type 2 diabetes. These preclinical studies suggest that sacubitril/valsartan may be an effective treatment for diabetic peripheral neuropathy, but additional studies will be needed to investigate these effects further.

Topics: Aminobutyrates; Angiotensin II Type 1 Receptor Blockers; Angiotensin Receptor Antagonists; Animals; Biphenyl Compounds; Cardiovascular Agents; Diabetes Mellitus, Type 2; Diabetic Angiopathies; Diabetic Neuropathies; Diabetic Retinopathy; Diet, High-Fat; Disease Progression; Drug Combinations; Male; Neprilysin; Neural Conduction; Neuroprotective Agents; Protease Inhibitors; Rats, Sprague-Dawley; Tetrazoles; Valsartan; Vascular Resistance

Diabetic retinopathy is a microvascular complication of diabetes mellitus whose prevalence is closely related to the presence of nephropathy and hypertension. The aim was to study clinical and pharmacological factors that are associated with an increased need for laser photocoagulation in patients with diabetic nephropathy and retinopathy.. Cross sectional study of 63 patients followed in the Diabetic Nephropathy consultation. Patients were divided into 2 groups according to whether or not previously have received photocoagulation. In each subgroup were studied demographic variables, anthropometric, laboratory, cardiovascular risk factors and treatment received by each patient for the control of hypertension, diabetes and others diseases.. We observed that the group had received photocoagulation had more years of diabetes evolution, more history of cardiovascular disease and a lower creatinine clearance. Similarly, the percentage of patients treated with carvedilol was significantly higher in the subgroup who had not received photocoagulation while the percentage of patients treated with beta-blockers was significantly higher in the subgroup that received photocoagulation; no significant differences was observed in the degree of control blood pressure.. Clinical and pharmacological factors related to the requirements of laser photocoagulation were years of diabetes evolution, history of cardiovascular disease, the stage of kidney disease and the treatment with beta-blockers.

Topics: Aged; Antihypertensive Agents; Atherosclerosis; Cardiovascular Agents; Cardiovascular Diseases; Comorbidity; Cross-Sectional Studies; Diabetes Mellitus, Type 2; Diabetic Nephropathies; Diabetic Retinopathy; Female; Humans; Hyperlipidemias; Hypertension; Hypoglycemic Agents; Hypolipidemic Agents; Insulin; Laser Coagulation; Male; Middle Aged; Recurrence; Risk Factors; Smoking

To review the role of cardiovascular disease and therapy in the onset and recurrence of preretinal/vitreous haemorrhage in diabetic patients.. Retrospective case note analysis of diabetic patients with vitreous haemorrhage from the Diabetic Eye Clinic at Birmingham Heartlands Hospital.. In total, 54 patients (mean age 57.1, 37 males, 20 type I vs 34 type II diabetic patients) were included. The mean (SD) duration of diagnosed diabetes at first vitreous haemorrhage was significantly longer, 21.9 (7.6) years for type I and 14.8 (9.3) years for type II diabetic patients (P < 0.01, unpaired t-test, two-tailed).Aspirin administration was not associated with a significantly later onset of vitreous haemorrhage. Four episodes were associated with ACE-inhibitor cough. There was a trend towards HMGCoA reductase inhibitor (statin) use being associated with a delayed onset of vitreous haemorrhage: 21.4 years until vitreous haemorrhage (treatment group) vs 16.2 years (nontreatment group) (P = 0.09, two-tailed, unpaired t-test, not statistically significant). During follow-up 56 recurrences occurred, making a total of 110 episodes of vitreous haemorrhage in 79 eyes of 54 patients. The mean (range) follow-up post haemorrhage was 1067 (77-3842) days, with an average of 1.02 recurrences. Age, gender, diabetes type (I or II) or control, presence of hypertension or hypercholesterolaemia, and macrovascular complications were not associated with a significant effect on the 1-year recurrence rate. Aspirin (and other antiplatelet or anticoagulant agents) and ACE- inhibitors appeared to neither increase nor decrease the 1-year recurrence rate. However, statin use was significantly associated with a reduction in recurrence (Fisher exact P < 0.05; two-tailed) with an odds ratio (95% CI) of 0.25 (0.1-0.95).. In this retrospective analysis, the onset of preretinal/vitreous haemorrhage was not found to be accelerated by gender, hypertension, hypercholesterolaemia, evidence of macrovascular disease, or HbA1c. Neither aspirin nor ACE-inhibitor administration accelerated the onset or recurrence of first vitreous haemorrhage. Statins may have a protective role, both delaying and reducing the recurrence of haemorrhage.

Topics: Adult; Aged; Angiotensin-Converting Enzyme Inhibitors; Aspirin; Cardiovascular Agents; Cardiovascular Diseases; Diabetes Mellitus, Type 1; Diabetes Mellitus, Type 2; Diabetic Retinopathy; Female; Humans; Hydroxymethylglutaryl-CoA Reductase Inhibitors; Hypercholesterolemia; Male; Middle Aged; Platelet Aggregation Inhibitors; Recurrence; Retinal Hemorrhage; Retrospective Studies; Vitreous Hemorrhage