What are the expected symptoms if hyperglycemia is caused by diabetes versus stress?

Symptoms of Hyperglycemia: Diabetes vs. Stress-Induced

Hyperglycemia caused by diabetes presents with classic symptoms of polydipsia (increased thirst), polyuria (frequent urination), and blurred vision, while stress-induced hyperglycemia typically presents with milder, transient symptoms that resolve when the stressor is removed. 1, 2

Diabetes-Induced Hyperglycemia

Primary Symptoms

• Persistent symptoms that develop gradually over time:
  • Increased thirst (polydipsia)
  • Frequent urination (polyuria)
  • Blurred vision
  • Unexplained weight loss (especially in type 1 diabetes)
  • Fatigue/drowsiness
  • Slow-healing wounds 1, 3

Severity Indicators

• Symptoms typically appear when blood glucose exceeds the renal threshold (approximately 180 mg/dL) 2
• HbA1c thresholds for symptom manifestation:
  • Type 1 diabetes: HbA1c > 10.05%
  • Type 2 diabetes: HbA1c > 8.9% 4

Progression and Complications

• If untreated, can progress to diabetic ketoacidosis (DKA), particularly in type 1 diabetes, with:
  • Nausea and vomiting
  • Abdominal pain
  • Fruity breath odor
  • High ketone levels in blood/urine
  • Confusion or altered mental status 1, 2
• Type 2 diabetes may progress to hyperosmolar hyperglycemic state (HHS) rather than DKA 1

Stress-Induced Hyperglycemia

Key Characteristics

• Temporary elevation in blood glucose due to:
  • Acute illness
  • Physical trauma
  • Surgery
  • Emotional stress
  • Medications (e.g., glucocorticoids) 1

Primary Symptoms

• Often milder and transient
• May be asymptomatic or present with:
  • Mild thirst
  • Slightly increased urination
  • Fatigue
• Symptoms resolve when the stressor is removed 1

Important Distinctions

• DKA rarely occurs spontaneously in stress-induced hyperglycemia unless:
  • The person already has undiagnosed diabetes
  • There's a severe illness like infection or myocardial infarction
  • The person is taking certain medications (glucocorticoids, second-generation antipsychotics, SGLT2 inhibitors) 1

Differential Diagnostic Features

Persistence of Symptoms

• Diabetes: Symptoms persist or worsen over time without treatment
• Stress-induced: Symptoms improve when stress resolves 1

Glucose Pattern

• Diabetes: Consistently elevated glucose levels, even during fasting
• Stress-induced: Glucose levels normalize after resolution of stressor 1

Risk Factors

• Diabetes: Family history, obesity, physical inactivity, history of gestational diabetes, certain ethnicities 1, 3
• Stress-induced: Acute illness, trauma, surgery, emotional distress 1

Clinical Pitfalls to Avoid

1. Misattribution: Don't assume hyperglycemia is stress-induced without ruling out underlying diabetes, especially in patients with risk factors
2. Delayed diagnosis: Stress can unmask previously undiagnosed diabetes or prediabetes
3. Inadequate follow-up: Always recheck glucose levels after stress resolution to confirm normalization
4. Overlooking type 1 diabetes: Remember that DKA can develop rapidly in type 1 diabetes, especially in those using insulin pumps 1, 2

Monitoring Recommendations

• For suspected stress-induced hyperglycemia:

  • Monitor glucose levels during and after resolution of stressor
  • Consider HbA1c testing to assess for chronic hyperglycemia
  • Follow up with fasting glucose after stress resolution 1

• For suspected diabetes:

  • Formal diagnostic testing (fasting glucose ≥126 mg/dL, HbA1c ≥6.5%, or 2-hour glucose ≥200 mg/dL during oral glucose tolerance test) 3
  • Assess for complications if diagnosis is confirmed