What lab test should a home health nurse evaluate to determine long-term management of blood glucose levels in a client with diabetes mellitus?

The measurement of HbA1C, or glycated hemoglobin, is essential for monitoring long-term blood glucose levels in individuals with diabetes mellitus. This test provides an average of a person's blood glucose levels over the past two to three months, reflecting how well the blood sugar has been managed during that period. It is a crucial indicator because it incorporates fluctuations in daily glucose readings and provides a more stable picture of diabetes control, allowing healthcare providers to assess the effectiveness of treatment plans and make necessary adjustments.

In contrast, other tests like fasting blood glucose and random blood glucose are snapshots of glucose levels at specific times but do not provide insight into overall blood sugar control over an extended period. Postprandial blood glucose, which measures blood sugar levels after eating, also lacks the long-term perspective achieved by the HbA1C test. Therefore, when evaluating long-term management of blood glucose levels, the HbA1C is the most informative and reliable choice.