Cut point of fasting blood sugar level indicates Diabetic Mellitus?

Appeared in: NORCET 2 -2021 (Shift-2)

Explanation

The American Diabetes Association (ADA) and WHO define a fasting plasma glucose (FPG) level of 126 mg/dL or higher as a diagnostic criterion for diabetes mellitus.
Fasting is defined as no caloric intake for at least 8 hours before the blood sample is taken.
This criterion must be confirmed by a repeat test on a different day, unless the patient presents with unequivocal symptoms of hyperglycemia.

Option A: A value greater than 200 mg/dL is the diagnostic threshold for a random plasma glucose test (with symptoms) or a 2-hour oral glucose tolerance test (OGTT), not a fasting test.
Option B: A value of 180 mg/dL is not a primary diagnostic criterion. It represents the approximate renal threshold for glucose, where glucose starts appearing in the urine.
Option D: A value greater than 140 mg/dL is used in the context of a 2-hour OGTT to diagnose impaired glucose tolerance (prediabetes), not diabetes itself.

Clinical Relevance

Nursing practice connection: Knowing Diagnostic criteria for Diabetes Mellitus helps nurses interpret findings accurately and avoid errors in routine assessment, medication administration, and patient teaching.
Accurate diagnosis of diabetes is crucial for initiating timely management, including lifestyle modifications and pharmacotherapy, to prevent acute and long-term complications.
Nurses play a vital role in educating patients about preparing for diagnostic tests (e.g., fasting requirements) and interpreting the results.
What if? If a patient's fasting blood sugar is 115 mg/dL, they would not be diagnosed with diabetes but with prediabetes (impaired fasting glucose). The nursing intervention would focus on intensive lifestyle modification (diet, exercise) to prevent progression to type 2 diabetes.

How to Approach the Question

Identify the key term in the question: 'Fasting blood sugar'.
Recall the standard diagnostic criteria for Diabetes Mellitus as established by major health organizations like the ADA and WHO.
Differentiate the fasting glucose criterion from other criteria like the oral glucose tolerance test (OGTT) and random blood sugar.
Compare the given options to the recalled standard value for fasting glucose.
Select the option that matches the established diagnostic cut-off point (≥126 mg/dL).

Concept Tested & Keywords

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Practise the full NORCET 2 -2021 (Shift-2)

Attempt every question from this paper in a timed mock, then review the full solution for each one.