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DM: Prevention and Treatment of Cardiovascular Disease (2001)

Citation:
 
Study Design:
Class:
- Click here for explanation of classification scheme.
Quality Rating:
Research Purpose:
To examine the cardiovascular complications of diabetes mellitus and consider opportunities for their prevention.
Inclusion Criteria:
None specifically mentioned.
Exclusion Criteria:
None specifically mentioned.
Description of Study Protocol:

Recruitment

Not specified.

Design

Consensus Statement.

Blinding Used (if applicable)

Not applicable.

Intervention (if applicable)

Not applicable.

Statistical Analysis

Data not analyzed statistically.

Data Collection Summary:

Timing of Measurements

Not applicable - consensus report.

Dependent Variables

Not applicable - consensus report.

Independent Variables

Not applicable - consensus report.

Control Variables

Description of Actual Data Sample:

Initial N:  Not described

Attrition (Final N):  Not described

Age:  Not mentioned

Ethnicity:  Not mentioned

Other relevant demographics:

Anthropometrics:

Location:  Studies from all over the world

Summary of Results:
Clinical Presentations of Diabetes Mellitus
 
The metabolic causes of type 2 diabetes are a combination of impairment in insulin-mediated glucose disposal (insulin resistance) and defective secretion of insulin by the pancreas.
 
Insulin resistance typically precedes the onset of other CVD risk factors (dyslipidemia, hypertension, and prothrombotic factors).
 
The common clustering of these risk factors in a single individual has been called the metabolic syndrome. This syndrome commonly precedes the development of type 2 diabetes by many years. Impaired fasting glucose is often present as well.
 
Diabetes and Specific CVD Atherosclerotic CHD
Both type 1 and 2 diabetes are independent risk factors for CHD. Also, myocardial ischemia due to coronary atherosclerosis commonly occurs without symptoms in patients with diabetes.
 
Diabetic Cardiomyopathy
A reason for poor prognosis in patients with both diabetes and ischemic heart disease seems to be an enhanced myocardial dysfunction leading to accelerated heart failure (cardiomyopathy).
 
Several factors probably underlie diabetic cardiomyopathy: severe coronary atherosclerosis, prolonged hypertension, chronic hyperglycemia, microvascular disease, glycosylation of myocardial proteins, and autonomic neuropathy.
 
Stroke
Mortality from stroke is increased ~3 fold when patients with diabetes are matched with nondiabetics.
 
The most common site of cerebrovascular disease in diabetes is occlusion of small paramedical penetrating arteries; severe carotid atherosclerosis is also common.
 
Renal Disease
~35% of patients with type 1 diabetes of 18 years duration will have signs of diabetic renal involvement. Up to 35% of new patients beginning dialysis therapy have type 2 diabetes. When diabetes is present, CVD is the leading cause of death among patients with end stage renal disease.
 
Covariate Risk Factors
Predisposing Risk Factors
Predisposing factors, which simultaneously affect the development of both CVD and diabetes, are obesity, physical inactivity, heredity, sex, and advancing age. These predisposing factors exacerbate the major risk factors of dyslipidemia, hypertension and glucose intolerance.
 
Insulin Resistance and Metabolic Syndrome
Most individuals with type 2 diabetes have insulin resistance and insulin resistance predisposes to both CVD and type 2 diabetes.
 
Factors that contribute to insulin resistance are genetics, obesity, physical inactivity, and advancing age. Those with insulin resistance often have abdominal obesity. Metabolic risk factors that occur commonly in patients with insulin resistance are atherogenic dyslipidemia, hypertension, glucose intolerance, and a prothrombotic state.
 
Atherogenic Dyslipidemia
Atherogenic dyslipidemia is characterized by 3 lipoprotein abnormalities: increased VLDL, small LDL particles, and low HDL. Each of he lipoprotein abnormalities is independently atherogenic.
 
Hypertension
When hypertension coexists with overt diabetes, the risk for CVD, including nephropathy, is increased twofold.
 
Elevated Plasma Glucose
For several years after the onset of insulin resistance, fasting and postprandial glucose levels typically are normal. Eventually, however, insulin secretion diminishes. The first abnormality in plasma glucose is impaired glucose tolerance (IGT) and IGT is a risk factor for both CVD and type 2 diabetes mellitus.
 
Prothromobotic State
Those with insulin resistance frequently manifest several alterations in coagulation mechanisms that predispose to arterial thrombosis. These alterations include increased fibrinogen, increased plasminogen activator inhibitor-1, and various platelet abnormalities.
 
LDL Cholesterol and Atherogenesis in Diabetic Patients
Most persons with diabetes do not have marked elevations of LDL-chol, but the levels are higher enough to support the development of atherosclerosis. Statin trials have demonstrated that aggressive LDL lowering therapy reduced current CHD events in patients with diabetes.
 
Cigarette Smoking
Patients with diabetes who smoke double their risk of CVD.
 
Diabetic Nephropathy
Microalbuminuria (urine albumin 30 to 300 mg/d or <300 mg/g creatinine) is the first clinical sign of diabetic damage to the kidney and also reflects a higher risk for CVD.
 
The majority of patients with microalbuminuria also have hypertension; treating the hypertension slows the declines of GFR.
 
Risk Assessment in the Diabetic Patient
Risk assessment must take into account major risk factors (cigarette smoking, high blood pressure, abnormal serum lipids and lipoproteins, and hyperglycemia) and predisposing risk factors (excess body weight and abdominal obesity, physical inactivity, and family history of CVD).
 
Cardiovascular Clinical Management
Medical Management
Comprehensive medical intervention in patients with established atherosclerotic CVD has the following benefits:
  1. extends overall survival
  2. improves quality of life
  3. reduces need for intervention procedures (angioplasty and CABG)
  4. reduces the incidence of subsequent MI
 
Comprehensive Risk Reduction for Patients with Coronary or Other Vascular Disease Who Have Diabetes
Comprehensive risk reduction in patients with coronary and other vascular diseases who have diabetes:
  1. smoking cessation
  2. blood pressure control (<135/85 mmHg)
  3. lipid management
    1. LDL < 100 mg/dl
    2. HDL > 35 mg/dl
    3. TG <200 mg/dl
  4. glucose control HbA1c<1% above normal
  5. weight management
  6. antiplatelet agents/anticoagulants
  7. ace inhibitors (post MI)
  8. beta blockers

Management of Diabetic Nephropathy

Slowing the progression nephropathy in diabetes include the following interventions: 1. control of hyperglycemia 2. treatment of hypertension 3. sodium restriction to ~2,400 mg/d 4. protein restriction to 0.8 g/kg/d

Author Conclusion:
The Scientific Advisory and Coordinating Committee of the American Heart Association (AHA) came to the conclusion that diabetes is a major risk factor for CVD. The AHA is giving greater emphasis on diabetes as a risk factor in its scientific and educational programs.
 
Primary prevention of CVD in individuals with either type 1 or 2 diabetes is the same as for those without diabetes except that more aggressive management of cholesterol and other lipids is recommended for those with diabetes.

 

Funding Source:
Not-for-profit
Reviewer Comments:

The RD needs to monitor microalbuminuria and adjust dietary protein intake when urine albumin is >30 gm/d.

Quality Criteria Checklist: Review Articles
Relevance Questions
  1. Will the answer if true, have a direct bearing on the health of patients? Yes
  2. Is the outcome or topic something that patients/clients/population groups would care about? Yes
  3. Is the problem addressed in the review one that is relevant to dietetics practice? Yes
  4. Will the information, if true, require a change in practice? Yes
 
Validity Questions
  1. Was the question for the review clearly focused and appropriate? N/A
  2. Was the search strategy used to locate relevant studies comprehensive? Were the databases searched and the search termsused described? ???
  3. Were explicit methods used to select studies to include in the review? Were inclusion/exclusion criteria specified andappropriate? Wereselectionmethods unbiased? No
  4. Was there an appraisal of the quality and validity of studies included in the review? Were appraisal methodsspecified,appropriate, andreproducible? No
  5. Were specific treatments/interventions/exposures described? Were treatments similar enough to be combined? N/A
  6. Was the outcome of interest clearly indicated? Were other potential harms and benefits considered? N/A
  7. Were processes for data abstraction, synthesis, and analysis described? Were they applied consistently acrossstudies and groups? Was thereappropriate use of qualitative and/or quantitative synthesis? Was variation in findings among studies analyzed? Were heterogeneity issued considered? If data from studies were aggregated for meta-analysis, was the procedure described? No
  8. Are the results clearly presented in narrative and/or quantitative terms? If summary statistics are used, are levels ofsignificance and/or confidence intervals included? N/A
  9. Are conclusions supported by results with biases and limitations taken into consideration? Are limitations ofthe review identified anddiscussed? N/A
  10. Was bias due to the review's funding or sponsorship unlikely? Yes