What scores are used to assess hypoglycemic encephalopathy?

Assessment Scores for Hypoglycemic Encephalopathy

The Clarke score, Gold score, and Pedersen-Bjergaard score are the validated tools recommended for assessing hypoglycemic encephalopathy, particularly for evaluating impaired hypoglycemia awareness in patients at risk. 1

Classification of Hypoglycemic Encephalopathy

Hypoglycemic encephalopathy is classified according to severity levels that guide clinical management:

1. Level 1 Hypoglycemia:

   • Glucose <70 mg/dL (3.9 mmol/L) and ≥54 mg/dL (3.0 mmol/L)
   • Represents threshold for neuroendocrine responses
   • Clinically important regardless of symptoms

2. Level 2 Hypoglycemia:

   • Glucose <54 mg/dL (3.0 mmol/L)
   • Threshold where neuroglycopenic symptoms begin
   • Requires immediate action

3. Level 3 Hypoglycemia:

   • Severe event with altered mental/physical status
   • Requires assistance for treatment
   • Independent of glucose level
   • Can progress to loss of consciousness, seizure, coma, or death

Validated Assessment Tools

Primary Assessment Tools

• Clarke Score: Evaluates hypoglycemia awareness through questionnaire-based assessment
• Gold Score: Quantifies impaired awareness of hypoglycemia
• Pedersen-Bjergaard Score: Assesses risk of severe hypoglycemia

Clinical Assessment Parameters

When evaluating patients with suspected hypoglycemic encephalopathy, these parameters should be assessed:

• Glasgow Coma Scale (GCS): Score <12 indicates hypoglycemic encephalopathy in the presence of severe hypoglycemia 2
• Duration of hypoglycemia: Prolonged hypoglycemia >480 minutes is associated with poor outcomes 3
• Body temperature: Higher body temperature correlates with prolonged encephalopathy 2

Diagnostic Imaging Findings

Neuroimaging is crucial for prognosis determination:

• MRI findings: Diffuse high-signal intensity on DWI in:

  • Cerebral cortex
  • Hippocampus
  • Head of caudate nucleus
  • Lentiform nucleus
  • Corpus callosum 4

• Normal brain imaging is significantly predictive of good outcomes (OR 7.1; 95% CI 1.1-44) 3

Risk Assessment for Hypoglycemic Encephalopathy

Regular screening is recommended for patients at risk:

• Screen individuals at risk for hypoglycemia for impaired awareness at least annually 1
• Screen high-risk individuals or those with severe/frequent hypoglycemia for fear of hypoglycemia at least annually 1

Prognostic Factors

Key factors affecting prognosis include:

• Blood glucose level: Lower glucose correlates with severity of altered consciousness 2
• Duration of hypoglycemia: All patients with hypoglycemia >480 minutes had poor outcomes 3
• Functional status prior to ICU admission: Lower pre-admission mRS predicts better outcomes (OR 2.6; 95% CI 1.1-6.3) 3
• Brain imaging findings: Widespread lesions in brain parenchyma or basal ganglia indicate poor prognosis 5

Common Pitfalls and Caveats

• Hypoglycemic encephalopathy can be misdiagnosed as acute cerebrovascular disease due to similar clinical presentation 4
• Patients who do not improve during the first 6 months typically do not recover consciousness 6
• Overall mortality is high (75% at 2 years in severe cases) 6
• Cognitive impairment at baseline increases risk for subsequent severe hypoglycemic episodes 1

Regular assessment of cognitive function with increased vigilance for hypoglycemia is recommended if impaired or declining cognition is found 1.