MEDLINE Abstracts: Diabetes and Cardiovascular Disease
MEDLINE Abstracts: Diabetes and Cardiovascular Disease
Heart Outcomes Prevention Evaluation Study Investigators.
Lancet 2000 Jan 22;355(9200):253-9
Background: Diabetes mellitus is a strong risk factor for cardiovascular and renal disease. We investigated whether the angiotensin-converting-enzyme (ACE) inhibitor ramipril can lower these risks in patients with diabetes.
Methods: 3577 people with diabetes included in the Heart Outcomes Prevention Evaluation study, aged 55 years or older, who had a previous cardiovascular event or at least one other cardiovascular risk factor, no clinical proteinuria, heart failure, or low ejection fraction, and who were not taking ACE inhibitors, were randomly assigned ramipril (10 mg/day) or placebo, and vitamin E or placebo, according to a two-by-two factorial design. The combined primary outcome was myocardial infarction, stroke, or cardiovascular death. Overt nephropathy was a main outcome in a substudy.
Findings: The study was stopped 6 months early (after 4.5 years) by the independent data safety and monitoring board because of a consistent benefit of ramipril compared with placebo. Ramipril lowered the risk of the combined primary outcome by 25% (95% CI 12-36, p=0.0004), myocardial infarction by 22% (6-36), stroke by 33% (10-50), cardiovascular death by 37% (21-51), total mortality by 24% (8-37), revascularisation by 17% (2-30), and overt nephropathy by 24% (3-40, p=0.027). After adjustment for the changes in systolic (2.4 mm Hg) and diastolic (1.0 mm Hg) blood pressures, ramipril still lowered the risk of the combined primary outcome by 25% (12-36, p=0.0004).
Interpretation: Ramipril was beneficial for cardiovascular events and overt nephropathy in people with diabetes. The cardiovascular benefit was greater than that attributable to the decrease in blood pressure. This treatment represents a vasculoprotective and renoprotective effect for people with diabetes.
Devaraj S, Jialal I
Circulation 2000 Jul 11;102(2):191-6
Background: Although diabetes confers an increased propensity toward accelerated atherogenesis, data are lacking on monocyte activity in type 2 diabetic patients with (DM2-MV) and without (DM2) macrovascular disease compared with control subjects. Thus, we tested whether (1) postsecretory modifications of LDL (glycation and oxidation), monocyte proatherogenic activity, and circulating levels of soluble cell adhesion molecules (sCAMs) are more pronounced in DM2-MV than in DM2 and control subjects and (2) RRR-alpha-tocopherol (AT) therapy, 1200 IU/d for 3 months, has a similar effect in the 3 groups (n=25 per group).
Methods and Results: Although LDL glycation was increased in both diabetic groups compared with control subjects, AT therapy had no significant effect on glycation. AT therapy significantly decreased LDL oxidizability in all 3 groups. Diabetic monocytes released significantly more superoxide anion (O(2)(-)) and interleukin-1beta (IL-1beta) and exhibited greater adhesion to endothelium than control subjects. AT therapy significantly decreased the release of O(2)(-), IL-1beta, tumor necrosis factor-alpha, and monocyte-endothelium adhesion in all 3 groups. There was no significant difference between the 2 diabetic groups for any of the above parameters. sICAM levels were significantly elevated in both diabetic groups compared with controls. AT therapy resulted in a significant decrease in sCAMs.
Conclusions: This is the first demonstration of increased IL-1beta secretion and increased adhesion of monocytes to endothelium from normotriglyceridemic diabetic subjects and of decreased monocyte activity and sCAMs with AT therapy in diabetic subjects with and without macrovasculopathy.
Valmadrid CT, Klein R, Moss SE, Klein BE
Arch Intern Med 2000 Apr 24;160(8):1093-100
Background: Despite the numerous studies on the relation of albuminuria with increased risk of all-cause mortality in type 2 diabetes mellitus, it remains uncertain whether microalbuminuria and/or gross proteinuria are independent risk factors for cardiovascular mortality. Moreover, the association of albuminuria with cardiovascular mortality in people with type 2 diabetes mellitus has not been well described in US populations.
Objective: To estimate the relative risks (RRs) for the associations of microalbuminuria and gross proteinuria with cardiovascular disease mortality among persons with older-onset diabetes mellitus.
Methods: We conducted a prospective cohort study of 840 people with older-onset diabetes mellitus who provided urine samples in the 1984-1986 examination of a population-based study of diabetic persons. The presence of microalbuminuria was determined by an agglutination inhibition assay and gross proteinuria by a reagent strip. The main outcome was time to mortality from cardiovascular disease, as determined from death certificates.
Results: Of the 840 older-onset diabetic persons, 54.8% had normoalbuminuria, while 24.8% had microalbuminuria and 20.5% had gross proteinuria. During the 12-year follow-up (6127 person-years), we identified 364 deaths from cardiovascular disease. Compared with persons with normoalbuminuria, those with microalbuminuria and gross proteinuria had significantly higher risks of cardiovascular mortality. The RR as controlled for age, sex, glycemic control, insulin use, alcohol intake, physical activity, cardiovascular disease history, antihypertensive use, and retinopathy severity, was 1.84 (95% confidence interval [CI], 1.42-2.40) for those with microalbuminuria and 2.61 (95% CI, 1.99-3.43) for those with gross proteinuria. Further adjustment for other factors did not change the relations we found. When the end point used was mortality from coronary heart disease, stroke, or all causes, the increased risks were significant for both microalbuminuria (adjusted RRs [95% CIs], 1.96 [1.42-2.72], 2.20 [1.29-3.75], and 1.68 [1.35-2.09], respectively) and gross proteinuria (adjusted RRs [95% CIs], 2.73 [1.95-3.81], 2.33 [1.28-4.24], and 2.47 [1.97-3.10], respectively).
Conclusions: Results from our population-based study strongly suggest that both microalbuminuria and gross proteinuria were significantly associated with subsequent mortality from all causes and from cardiovascular, cerebrovascular, and coronary heart diseases. These associations were independent of known cardiovascular risk factors and diabetes-related variables.
Takemoto M, Yokote K, Nishimura M, et al
Arterioscler Thromb Vasc Biol 2000 Mar;20(3):624-8
We have previously reported that high glucose stimulates osteopontin (OPN) expression through protein kinase C-dependent pathways as well as hexosamine pathways in cultured rat aortic smooth muscle cells. The finding prompted us to study in vivo expression of OPN in diabetes mellitus. In the present study, we found by immunohistochemistry that medial layers of the carotid arteries of streptozotocin-induced diabetic rats and the forearm arteries of diabetic patients stained positively for OPN antibodies, whereas the staining from arteries of control rats and nondiabetic patients was negative. We also found that OPN stimulated the migration and enhanced platelet-derived growth factor (PDGF)-mediated DNA synthesis of cultured rat aortic smooth muscle cells. OPN and PDGF synergistically activated focal adhesion kinase as well as extracellular signal-regulated kinase; this finding seems to explain the OPN-induced enhancement of PDGF-mediated DNA synthesis. Taken together, our present results raise a possibility that OPN plays a role in the development of diabetic vascular complications.
MEDLINE Abstracts: Diabetes and Cardiovascular Disease
Effects of Ramipril on Cardiovascular and Microvascular Outcomes in People with Diabetes Mellitus: Results of the HOPE Study and MICRO-HOPE Substudy.
Heart Outcomes Prevention Evaluation Study Investigators.
Lancet 2000 Jan 22;355(9200):253-9
Background: Diabetes mellitus is a strong risk factor for cardiovascular and renal disease. We investigated whether the angiotensin-converting-enzyme (ACE) inhibitor ramipril can lower these risks in patients with diabetes.
Methods: 3577 people with diabetes included in the Heart Outcomes Prevention Evaluation study, aged 55 years or older, who had a previous cardiovascular event or at least one other cardiovascular risk factor, no clinical proteinuria, heart failure, or low ejection fraction, and who were not taking ACE inhibitors, were randomly assigned ramipril (10 mg/day) or placebo, and vitamin E or placebo, according to a two-by-two factorial design. The combined primary outcome was myocardial infarction, stroke, or cardiovascular death. Overt nephropathy was a main outcome in a substudy.
Findings: The study was stopped 6 months early (after 4.5 years) by the independent data safety and monitoring board because of a consistent benefit of ramipril compared with placebo. Ramipril lowered the risk of the combined primary outcome by 25% (95% CI 12-36, p=0.0004), myocardial infarction by 22% (6-36), stroke by 33% (10-50), cardiovascular death by 37% (21-51), total mortality by 24% (8-37), revascularisation by 17% (2-30), and overt nephropathy by 24% (3-40, p=0.027). After adjustment for the changes in systolic (2.4 mm Hg) and diastolic (1.0 mm Hg) blood pressures, ramipril still lowered the risk of the combined primary outcome by 25% (12-36, p=0.0004).
Interpretation: Ramipril was beneficial for cardiovascular events and overt nephropathy in people with diabetes. The cardiovascular benefit was greater than that attributable to the decrease in blood pressure. This treatment represents a vasculoprotective and renoprotective effect for people with diabetes.
Low-Density Lipoprotein Postsecretory Modification, Monocyte Function, and Circulating Adhesion Molecules in Type 2 Diabetic Patients with and without Macrovascular Complications: The Effect of Alpha-tocopherol Supplementation.
Devaraj S, Jialal I
Circulation 2000 Jul 11;102(2):191-6
Background: Although diabetes confers an increased propensity toward accelerated atherogenesis, data are lacking on monocyte activity in type 2 diabetic patients with (DM2-MV) and without (DM2) macrovascular disease compared with control subjects. Thus, we tested whether (1) postsecretory modifications of LDL (glycation and oxidation), monocyte proatherogenic activity, and circulating levels of soluble cell adhesion molecules (sCAMs) are more pronounced in DM2-MV than in DM2 and control subjects and (2) RRR-alpha-tocopherol (AT) therapy, 1200 IU/d for 3 months, has a similar effect in the 3 groups (n=25 per group).
Methods and Results: Although LDL glycation was increased in both diabetic groups compared with control subjects, AT therapy had no significant effect on glycation. AT therapy significantly decreased LDL oxidizability in all 3 groups. Diabetic monocytes released significantly more superoxide anion (O(2)(-)) and interleukin-1beta (IL-1beta) and exhibited greater adhesion to endothelium than control subjects. AT therapy significantly decreased the release of O(2)(-), IL-1beta, tumor necrosis factor-alpha, and monocyte-endothelium adhesion in all 3 groups. There was no significant difference between the 2 diabetic groups for any of the above parameters. sICAM levels were significantly elevated in both diabetic groups compared with controls. AT therapy resulted in a significant decrease in sCAMs.
Conclusions: This is the first demonstration of increased IL-1beta secretion and increased adhesion of monocytes to endothelium from normotriglyceridemic diabetic subjects and of decreased monocyte activity and sCAMs with AT therapy in diabetic subjects with and without macrovasculopathy.
The Risk of Cardiovascular Disease Mortality Associated with Microalbuminuria and Gross Proteinuria in Persons with Older-Onset Diabetes Mellitus.
Valmadrid CT, Klein R, Moss SE, Klein BE
Arch Intern Med 2000 Apr 24;160(8):1093-100
Background: Despite the numerous studies on the relation of albuminuria with increased risk of all-cause mortality in type 2 diabetes mellitus, it remains uncertain whether microalbuminuria and/or gross proteinuria are independent risk factors for cardiovascular mortality. Moreover, the association of albuminuria with cardiovascular mortality in people with type 2 diabetes mellitus has not been well described in US populations.
Objective: To estimate the relative risks (RRs) for the associations of microalbuminuria and gross proteinuria with cardiovascular disease mortality among persons with older-onset diabetes mellitus.
Methods: We conducted a prospective cohort study of 840 people with older-onset diabetes mellitus who provided urine samples in the 1984-1986 examination of a population-based study of diabetic persons. The presence of microalbuminuria was determined by an agglutination inhibition assay and gross proteinuria by a reagent strip. The main outcome was time to mortality from cardiovascular disease, as determined from death certificates.
Results: Of the 840 older-onset diabetic persons, 54.8% had normoalbuminuria, while 24.8% had microalbuminuria and 20.5% had gross proteinuria. During the 12-year follow-up (6127 person-years), we identified 364 deaths from cardiovascular disease. Compared with persons with normoalbuminuria, those with microalbuminuria and gross proteinuria had significantly higher risks of cardiovascular mortality. The RR as controlled for age, sex, glycemic control, insulin use, alcohol intake, physical activity, cardiovascular disease history, antihypertensive use, and retinopathy severity, was 1.84 (95% confidence interval [CI], 1.42-2.40) for those with microalbuminuria and 2.61 (95% CI, 1.99-3.43) for those with gross proteinuria. Further adjustment for other factors did not change the relations we found. When the end point used was mortality from coronary heart disease, stroke, or all causes, the increased risks were significant for both microalbuminuria (adjusted RRs [95% CIs], 1.96 [1.42-2.72], 2.20 [1.29-3.75], and 1.68 [1.35-2.09], respectively) and gross proteinuria (adjusted RRs [95% CIs], 2.73 [1.95-3.81], 2.33 [1.28-4.24], and 2.47 [1.97-3.10], respectively).
Conclusions: Results from our population-based study strongly suggest that both microalbuminuria and gross proteinuria were significantly associated with subsequent mortality from all causes and from cardiovascular, cerebrovascular, and coronary heart diseases. These associations were independent of known cardiovascular risk factors and diabetes-related variables.
Enhanced Expression of Osteopontin in Human Diabetic Artery and Analysis of its Functional Role in Accelerated Atherogenesis.
Takemoto M, Yokote K, Nishimura M, et al
Arterioscler Thromb Vasc Biol 2000 Mar;20(3):624-8
We have previously reported that high glucose stimulates osteopontin (OPN) expression through protein kinase C-dependent pathways as well as hexosamine pathways in cultured rat aortic smooth muscle cells. The finding prompted us to study in vivo expression of OPN in diabetes mellitus. In the present study, we found by immunohistochemistry that medial layers of the carotid arteries of streptozotocin-induced diabetic rats and the forearm arteries of diabetic patients stained positively for OPN antibodies, whereas the staining from arteries of control rats and nondiabetic patients was negative. We also found that OPN stimulated the migration and enhanced platelet-derived growth factor (PDGF)-mediated DNA synthesis of cultured rat aortic smooth muscle cells. OPN and PDGF synergistically activated focal adhesion kinase as well as extracellular signal-regulated kinase; this finding seems to explain the OPN-induced enhancement of PDGF-mediated DNA synthesis. Taken together, our present results raise a possibility that OPN plays a role in the development of diabetic vascular complications.