Diabetes Mellitus Lecture Notes

Definitions and Overview

• Diabetes Mellitus: Describes diseases of abnormal carbohydrate metabolism characterized by hypoglycemia and elevated blood glucose levels.
• Uncontrolled Diabetes: Increases the risk of cardiovascular disease, kidney disease, and nerve damage.

Normal Carbohydrate Metabolism

• Carbohydrates (e.g., bread) are broken down into glucose.
• Insulin: Secreted by beta cells in the pancreas in response to increased blood glucose levels.
• Insulin Function:
  • Promotes glucose storage in tissues by binding to insulin receptors.
  • Allows glucose uptake into cells (e.g., liver, heart, kidney, nerves).
  • Stimulates glycolysis and energy production.
  • Promotes glucose storage as glycogen.

Diabetes Pathophysiology

• Insulin Issues: Problems in insulin secretion or resistance can lead to hypoglycemia.
• Associated complications: cardiovascular disease, chronic kidney disease, neuropathy.

Types of Diabetes

• Type 1 Diabetes:
  • Autoimmune destruction of pancreatic beta cells.
  • Leads to absolute insulin deficiency and increased blood glucose levels.
  • Typically diagnosed in childhood.
  • Can present with diabetic ketoacidosis.
• Type 2 Diabetes:
  • Most common in adults.
  • Characterized by insulin resistance and defective insulin secretion.
  • Often asymptomatic at presentation.
  • Influenced by environmental factors, aging, and genetics.

Complications

• Microvascular Complications:
  • Retinopathy and cataracts.
  • Neuropathies: Peripheral (sensory loss, risk of foot ulcers), Autonomic (erectile dysfunction, postural hypotension, gastroparesis).
  • Nephropathy leading to proteinuria and end-stage renal failure.
• Macrovascular Complications:
  • Peripheral vascular disease (causes pain in the calf when walking).
  • Cardiovascular disease (risk of myocardial infarction).
  • Cerebral vascular disease (risk of stroke).

Management of Diabetes

• General Recommendations:
  • Patient education.
  • Aim for HbA1c < 7 (indicates average blood glucose levels over 3 months).
  • Maintain normal blood pressure and cholesterol levels.
  • Smoking cessation, exercise, and diet.
  • Monitoring for complications.
• Pharmacological Management:
  • Type 1 Diabetes: Insulin therapy due to absolute insulin deficiency.
  • Type 2 Diabetes: Starts with oral or subcutaneous hypoglycemic agents, may progress to insulin.

Summary

• Discussed type 1 and type 2 diabetes mellitus.
• Covered chronic complications (microvascular and macrovascular).
• Reviewed general management strategies for diabetes mellitus.