Diabetes Mellitus

Diabetes Mellitus

• A chronic condition characterized by raised plasma glucose levels, resulting from the body's inability to produce or use insulin properly.
• Regulation of plasma glucose levels involves the balance between insulin and glucagon.

Types of Diabetes

• Type 1 Diabetes: Destruction of B-cells, leading to absolute insulin deficiency, with two subtypes:
  • Immune-mediated
  • Idiopathic
• Type 2 Diabetes: May range from predominantly insulin resistance with relative insulin deficiency to insulin deficiency with insulin resistance.

Risk Factors

• Type 1 Diabetes:
  • Genetic predisposition
  • Triggering event (e.g., virus or toxin)
• Type 2 Diabetes:
  • Family history
  • Obesity
  • Habitual physical inactivity
  • Previously identified impaired glucose tolerance (IGT) or impaired fasting glucose (IFG)
  • Hypertension
  • Hyperlipidemia

Other Causes of Diabetes

• Diseases of the Exocrine Pancreas:
  • Pancreatitis
  • Pancreatectomy
  • Neoplasia
  • Cystic Fibrosis
  • Hemochromatosis
• Endocrinopathies:
  • Acromegaly
  • Cushing's syndrome
  • Glucagonoma
  • Pheochromocytoma
  • Hyperthyroidism
• Drug- or Chemical-Induced Diabetes:
  • Glucocorticoids
  • Thyroid hormone
  • b-adrenergic agonists
  • Thiazides
  • a-interferon
  • Beta blockers

Gestational Diabetes Mellitus (GDM)

• First recognized during pregnancy
• Diagnostic criteria: any one test should be confirmed with a second test, most often fasting plasma glucose (FPG)

Signs and Symptoms

• Excessive thirst (polydipsia)
• Excessive urination (polyuria)
• Dehydration
• Excessive hunger (polyphagia)
• Tiredness
• Weight loss
• Blurred vision
• Muscle weakness
• Acne
• Erectile failure
• Fungal infections
• Diabetic foot

Diabetes Mellitus Complications

• Microvascular Complications:
  • Retinopathy
  • Nephropathy
  • Neuropathy
• Macrovascular Complications:
  • Coronary artery disease
  • Peripheral vascular disease
  • Cerebrovascular disease
  • Gastrointestinal disease
  • Genitourinary disease

Diabetic Retinopathy

• Microaneurysm
• Hemorrhage
• Exudates
• Retinal edema
• Other

Diabetic Nephropathy

• 30-40% of all type 1 DM patients develop nephropathy in 20 years
• 15-20% of type 2 DM patients develop nephropathy
• Manifested as:
  • Microalbuminuria
  • Progressive diabetic nephropathy leading to end-stage renal disease

Diabetic Neuropathy

• Autonomic Neuropathy:
  • Orthostatic hypotension
  • Diabetic diarrhea
  • Erectile dysfunction
  • Difficulty in urination

Peripheral Vascular Disease and Foot Ulcer

• Incidence of gangrene of the feet in DM is 20-fold higher than control group due to:
  • Ischemia
  • Peripheral neuropathy
  • Secondary infection

Diabetic Ketoacidosis

• A true emergency
• Usually results from omitting insulin in type 1 DM or increase insulin requirements in other illness (e.g., infection, trauma) in type 1 DM and type 2 DM
• Signs and symptoms:
  • Fatigue
  • Nausea
  • Vomiting
  • Evidence of dehydration
  • Rapid deep breathing
  • Fruity breath odor
  • Hypotension
  • Tachycardia

Management of Diabetic Ketoacidosis

• Fluid administration
• IV infusion of insulin
• Titrate the dose according to the blood glucose level
• Potassium and phosphate can be added to the fluid if needed
• Follow up:
  • Metabolic improvement is manifested by an increase in serum bicarbonate or pH

Treatment

• Desired Outcome:
  • Relieve symptoms
  • Reduce mortality
  • Improve quality of life
  • Reduce the risk of microvascular and macrovascular disease complications
• How to Achieve the Goals:
  • Near normal glycemic control
  • Control of traditional CV risk factors
  • Medications
  • Dietary and exercise modification
  • Regular complication monitoring
  • Self-monitoring of blood glucose

Treatment Options

• DPP4 Inhibitor:
  • Advantages: weight neutral, decreases postprandial glucose, once a day, well-tolerated
  • Disadvantages: heart failure (saxagliptin/alogliptin), arthritis, rare pancreatitis
• SGLT2 Inhibitor:
  • Advantages: weight loss, decreases heart failure, decreases renal dysfunction, no hypoglycemia
  • Disadvantages: urinary tract infections, genital mycotic infections, increased LDL, increased risk of DKA

Insulin

• Types of Insulin:
  • Rapid-acting insulin
  • Short-acting insulin
  • Intermediate-acting insulin
  • Long-acting insulin
  • Ultra-long-acting insulin
  • Remixed insulin
• Insulin Regimens:
  • Multiple daily injections
  • Basal-bolus insulin regimen
  • Premixed insulin regimen