Insulin, Fasting
CPT Code(s):
83525
Turnaround Time:
4 hours
Specimen Requirements
Preferred Specimen:
Serum
Minimum Volume:
1.0 mL
Transport Container:
Serum Separator Tube (SST) or Red Top Tube
Transport Temperature:
Room Temperature
Collection Instructions:
Collect first fasting specimen before adminstering 75 gram Glucola. Draw second specimen 2 hours post Glucola. Allow blood to clot completely prior to centrifugation. Separate serum from cells within 45 minutes of collection.
Rejection Criteria:
Gross hemolysis; lipemia; improper labeling
Stability Criteria
Room Temperature:
2 hours
Refrigerated:
24 hours
Frozen:
30 days
Clinical Significance
The Insulin, Fasting test holds specific clinical significance and diagnostic use in measuring insulin levels in a patient's blood after an overnight fast. It plays a crucial role in evaluating insulin production, insulin resistance, and glucose metabolism in various clinical scenarios.
The specific clinical significance and diagnostic use of the Insulin, Fasting test include:
1. Diabetes Diagnosis: The test aids in diagnosing diabetes by assessing fasting insulin levels. Low insulin levels may indicate impaired insulin secretion and are commonly observed in type 1 diabetes. Elevated insulin levels in the presence of high blood glucose levels may suggest insulin resistance, a characteristic feature of type 2 diabetes.
2. Insulin Resistance Assessment: Insulin resistance occurs when the body's cells do not respond effectively to insulin's actions. Measuring fasting insulin levels helps evaluate insulin resistance, particularly in patients at risk of metabolic disorders, such as obesity, polycystic ovary syndrome (PCOS), and metabolic syndrome.
3. Monitoring Diabetes Management: For individuals with diabetes, the Insulin, Fasting test helps assess the efficacy of insulin therapy or other glucose-lowering medications. Monitoring fasting insulin levels can guide treatment adjustments, ensuring optimal glycemic control and reducing the risk of long-term complications.
4. Research and Clinical Trials: The Insulin, Fasting test is employed in research studies and clinical trials to investigate insulin-related mechanisms, insulin sensitivity, and therapeutic interventions targeting insulin regulation and glucose metabolism.
Interpretation of the Insulin, Fasting test results should consider the patient's clinical context, including concurrent fasting blood glucose levels and other metabolic parameters. The test is often used in conjunction with other assessments, such as fasting plasma glucose or glycated hemoglobin (HbA1c), to provide a comprehensive evaluation of glucose and insulin regulation.
In summary, the Insulin, Fasting test is specifically used for diabetes diagnosis, assessing insulin resistance, monitoring diabetes management, and supporting research and clinical trials focused on insulin-related mechanisms. It provides valuable information about insulin production, insulin sensitivity, and glucose metabolism, aiding in the understanding and management of metabolic disorders. Close collaboration between healthcare providers and patients is crucial to interpret the test results accurately and implement appropriate treatment plans.