Interpret 2-hour glucose tolerance test results: fasting glucose 85 mg/dL, 1-hour 76 mg/dL, 2-hour 99 mg/dL

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Last updated: February 18, 2025 • View editorial policy

From the Guidelines

Interpretation of 2-Hour Glucose Tolerance Test Results

This individual's 2-hour glucose tolerance test results, with a fasting glucose of 85 mg/dL, 1-hour glucose of 76 mg/dL, and 2-hour glucose of 99 mg/dL, indicate impaired glucose tolerance since the 2-hour glucose level is below the diagnostic threshold for diabetes (140 mg/dL or higher) but above normal (less than 140 mg/dL) 1.

Implications and Recommendations

Given these results, it is crucial to counsel the individual on lifestyle modifications to prevent the progression to diabetes, including:

  • A healthy diet low in added sugars and saturated fats
  • Regular physical activity, aiming for at least 150 minutes of moderate-intensity aerobic exercise per week
  • Weight management to maintain a healthy weight

Monitoring of glucose levels should also be considered, and a repeat test may be necessary in the future to assess for any changes in glucose tolerance 2.

Management Approach

No medication is currently recommended for impaired glucose tolerance. However, the individual should be encouraged to adopt and maintain a healthy lifestyle. Close follow-up with a healthcare provider is advised to monitor for any signs of diabetes or other metabolic disorders and to adjust the management plan as necessary. This approach is based on the criteria for diagnosing diabetes and impaired glucose tolerance outlined in studies such as 1 and 2, which emphasize the importance of early intervention and lifestyle changes in managing impaired glucose tolerance and preventing the onset of diabetes.

From the Research

Interpretation of 2-Hour Glucose Tolerance Test Results

The given 2-hour glucose tolerance test results are: fasting glucose 85 mg/dL, 1-hour 76 mg/dL, and 2-hour 99 mg/dL.

Normal and Impaired Glucose Tolerance

According to 3, impaired glucose tolerance is defined as two-hour glucose levels of 140 to 199 mg per dL on the 75-g oral glucose tolerance test. Since the 2-hour glucose level is 99 mg/dL, which is below 140 mg/dL, it does not meet the criteria for impaired glucose tolerance.

1-Hour Post-Load Glucose Level

Studies 4, 5, and 6 suggest that the 1-hour post-load glucose level during the oral glucose tolerance test can be a useful biomarker for detecting dysglycaemia. However, the 1-hour glucose level of 76 mg/dL in this case is below the threshold of 155 mg/dL proposed by 4 for identifying individuals with reduced β-cell function.

Comparison with Diagnostic Criteria

The results do not meet the criteria for impaired glucose tolerance or impaired fasting glucose as defined by 3. The 2-hour glucose level is below 140 mg/dL, and the fasting glucose level is below 100 mg/dL.

Risk of Metabolic Syndrome and Diabetes

Although the given glucose levels do not indicate impaired glucose tolerance, studies 7 and 6 suggest that even normal glucose levels can be associated with an increased risk of metabolic syndrome and diabetes if other risk factors are present. However, based on the provided information, it is not possible to assess the individual's risk without considering other factors such as family history, body mass index, and lifestyle.

Key Points

  • The 2-hour glucose tolerance test results do not indicate impaired glucose tolerance.
  • The 1-hour post-load glucose level is below the proposed threshold for identifying individuals with reduced β-cell function.
  • Other risk factors should be considered to assess the individual's risk of metabolic syndrome and diabetes.

Professional Medical Disclaimer

This information is intended for healthcare professionals. Any medical decision-making should rely on clinical judgment and independently verified information. The content provided herein does not replace professional discretion and should be considered supplementary to established clinical guidelines. Healthcare providers should verify all information against primary literature and current practice standards before application in patient care. Dr.Oracle assumes no liability for clinical decisions based on this content.