What are the symptoms and treatment of diabetes type 1?

Symptoms of Type 1 Diabetes

The classic symptoms of type 1 diabetes include polyuria (excessive urination), polydipsia (excessive thirst), weight loss, polyphagia (increased hunger), fatigue, and blurred vision, typically occurring for several days to a few weeks prior to diagnosis. 1

Clinical Presentation

Type 1 diabetes symptoms typically develop rapidly and can be categorized as follows:

Common Initial Symptoms

• Polyuria - Excessive urination due to osmotic diuresis from hyperglycemia
• Polydipsia - Extreme thirst resulting from fluid loss and dehydration
• Unexplained weight loss - Despite increased appetite
• Polyphagia - Increased hunger
• Fatigue - Due to inability to use glucose for energy
• Blurred vision - From lens swelling caused by osmotic effects of chronic hyperglycemia 1

Advanced or Severe Symptoms

• Diabetic ketoacidosis (DKA) symptoms:
  • Nausea and vomiting
  • Abdominal pain
  • Fruity breath odor (from ketones)
  • Rapid breathing
  • Confusion or altered mental status
  • Potential progression to loss of consciousness, seizure, or coma 1

Diagnostic Criteria

Type 1 diabetes can be diagnosed through the following criteria:

• Random plasma glucose ≥200 mg/dL (11.1 mmol/L) with classic symptoms of hyperglycemia 1
• Fasting plasma glucose ≥126 mg/dL (7.0 mmol/L) after no caloric intake for at least 8 hours
• 2-hour plasma glucose ≥200 mg/dL (11.1 mmol/L) during oral glucose tolerance test
• HbA1c ≥6.5% (48 mmol/mol) 1

Stages of Type 1 Diabetes Development

Type 1 diabetes develops in three distinct stages:

1. Stage 1: Presymptomatic with β-cell autoimmunity (≥2 islet autoantibodies) and normoglycemia
2. Stage 2: Presymptomatic with β-cell autoimmunity and dysglycemia
3. Stage 3: Symptomatic disease with insulin deficiency 1

Treatment Approach

The cornerstone of type 1 diabetes treatment is insulin replacement therapy:

Insulin Therapy

• Multiple daily injections (MDI) - 3-4 injections per day of basal and prandial insulin
• Continuous subcutaneous insulin infusion (CSII) via insulin pump 1
• Most patients should be educated to match prandial insulin doses to carbohydrate intake, pre-meal blood glucose levels, and anticipated activity 1

Insulin Types and Administration

• Basal insulin: Long-acting insulin analogs (e.g., insulin glargine) typically administered once daily at bedtime 2
• Bolus insulin: Rapid-acting insulin administered before meals
• Typical distribution: 50% basal insulin and 50% bolus insulin 3

Monitoring

• Self-monitoring of blood glucose (SMBG)
• Continuous glucose monitoring (CGM) - Particularly beneficial for patients with frequent hypoglycemia or hypoglycemia unawareness 4

Hypoglycemia Management

• For mild to moderate hypoglycemia (blood glucose <70 mg/dL): 15-20g of fast-acting carbohydrates, preferably glucose
• For severe hypoglycemia: Glucagon administration by caregivers or family members 4
• Patients should be advised to carry fast-acting carbohydrates at all times 4

Complications to Monitor

Untreated or poorly controlled type 1 diabetes can lead to:

Acute Complications

• Diabetic ketoacidosis (DKA) - Life-threatening condition requiring immediate medical attention
• Severe hypoglycemia - Can progress to loss of consciousness, seizure, coma, or death 1, 5

Chronic Complications

• Microvascular: Retinopathy, nephropathy, neuropathy
• Macrovascular: Coronary artery disease, peripheral vascular disease
• Regular screening for these complications is essential 5

Important Considerations

• Early diagnosis and treatment are critical - The metabolic state of untreated children with type 1 diabetes can deteriorate rapidly 1
• Delays in diagnosis and insulin therapy must be avoided to prevent progression to DKA 1
• Hypoglycemia awareness should be assessed regularly, as repeated episodes can lead to hypoglycemia unawareness 4
• Adjunctive therapies such as pramlintide may be considered in some patients but are not first-line treatments 1, 3

Type 1 diabetes requires lifelong insulin therapy, and proper education on insulin administration, carbohydrate counting, and hypoglycemia management is essential for optimal outcomes and quality of life.