Understanding Diabetes and Its Types

Diabetes

• Chronic metabolic disease characterized by elevated blood glucose levels.
• Can lead to serious damage to heart, blood vessels, eyes, kidneys, and nerves over time.

Type 1 Diabetes

• Juvenile diabetes or insulin-dependent diabetes.
• Body produces little or no insulin.
• Most common type is immune-mediated.
• Often diagnosed before the age of 30, but can occur at any age.

Type 2 Diabetes

• Adult-onset diabetes
• Body becomes resistant to insulin or doesn't produce enough.

Diabetes Statistics

• 537 million adults are living with diabetes.
• Projected to rise to 643 million by 2030 and 783 million by 2045.
• 3 in 4 adults with diabetes live in low- and middle-income countries.
• Over 90% of adults with diabetes have type 2.

The Pancreas

• Contains Islets of Langerhans cells.
• Produces hormones:
  • Insulin: Storage and anabolic hormone.
  • Glucagon: Hyperglycemic factor that raises blood glucose.

Insulin

• Secreted by beta-cells of Islets of Langerhans.
• Stimuli for release: Sugars, amino acids, GLP-1, GIP, glucagon, cholecystokinin, high concentrations of fatty acids, and beta-adrenergic sympathetic activity.
• Incretins (GIP and GLP-1) are hormones released from the gut in response to food, they increase insulin release.
• Dipeptidyl peptidase (DPP-4) terminates their action.

Insulin Release

• Continuous basal secretion with surges at feeding times.
• Beta-cells possess K+ channels regulated by intracellular ATP (KATP channels).
• Increase in blood glucose leads to increased ATP in beta-cells.
• ATP closes KATP channels.
• Depolarization of beta-cell initiates Ca2+ influx.
• Ca2+ influx triggers insulin release.

Type 1 Diabetes

• Severe or absolute insulin deficiency.
• Results in decreased glucose uptake by insulin-sensitive tissues.
• Leads to lipolysis and muscle proteolysis, causing weight loss and weakness.
• Increased levels of free fatty acids and glycerol.
• Acetyl-CoA is converted to ketone bodies, causing acidosis (ketoacidosis).

Type 2 Diabetes

• Tissue resistance to insulin and relative deficiency in insulin secretion.
• Initially, patients can be controlled with diet, exercise, and non-insulin glucose-lowering drugs.
• Some patients develop progressive beta cell failure and require insulin therapy.

Gestational Diabetes

• Abnormal glucose levels during pregnancy.
• Placenta and placental hormones create insulin resistance.

Other Specific Types of Diabetes

• Pancreatectomy, pancreatitis, non-pancreatic diseases, drug therapy, etc.

Laboratory Findings

• Plasma or serum glucose: ≥126 mg/dL (7 mmol/L) on more than one occasion after at least 8 hours of fasting is diagnostic.
• HbA1c measurements: Reflect glucose levels over the preceding 8-12 weeks.
  • Normal range: 4-6%
  • Elevated in people with diabetes.
• Oral Glucose Tolerance Test (OGTT)

Drugs Used in the Treatment of Diabetes

• Insulin:
  • Human Insulin: Rapid, short, intermediate, long-acting.
  • Insulin Analogs: Rapid (lispro, aspart, glulisine), short (regular), intermediate (NPH), long (glargine, detemir, degludec).
• Sulfonylureas:
  • Glipizide, glyburide, glimepiride.
• Meglitinides:
  • Repaglinide, nateglinide.
• Thiazolidinediones:
  • Pioglitazone, rosiglitazone.
• Alpha-glucosidase inhibitors:
  • Acarbose, miglitol.
• GLP-1 receptor agonists:
  • Exenatide, liraglutide, semaglutide, dulaglutide.
• DPP-4 inhibitors:
  • Sitagliptin, saxagliptin, linagliptin.
• Sodium-glucose co-transporter 2 (SGLT2) inhibitors:
  • Canagliflozin, dapagliflozin, empagliflozin.
• Other drugs:
  • Metformin, D-phenylalanine analogs.

Drug Interactions

• Beta-blockers:
  • Can worsen diabetes and dyslipidemia.
  • May increase the risk of hypoglycemia by blunting the symptoms.
  • Increase the risk of developing diabetes in patients with hypertension (except for diuretics).

Acute Complications of Diabetes

• Hypoglycemia:
  • Most common complication of insulin therapy and oral agents that stimulate insulin secretion.
  • Occurs more frequently with long-acting sulfonylureas.
  • Symptoms: Autonomic hyperactivity (sympathetic and parasympathetic), convulsions, coma.

Chronic Complications of Diabetes

• Microvascular complications:
  • Retinopathy, nephropathy, neuropathy.
• Macrovascular complications:
  • Myocardial infarction, stroke.
• End-stage chronic kidney disease:
  • Higher prevalence in patients with type 1 diabetes.

Tobacco Use

• Increases the risk of both microvascular and macrovascular complications in patients with diabetes.

This quiz explores the chronic metabolic disease known as diabetes, including its types, statistics, and the role of the pancreas. Test your knowledge about Type 1 and Type 2 diabetes, their effects on health, and the hormonal functions involved. Ideal for students and healthcare professionals alike.