“What is my blood sugar supposed to be?”
A client who was recently diagnosed with type 2 diabetes may ask a Registered Dietitian (RD) this question during a counseling session. The client’s health care provider might have given him or her a glucose monitor, demonstrated how to perform a blood sugar test, and discussed goals for glucose testing. However, because the client probably was overwhelmed with the new diabetes diagnosis, he or she might have been unable to understand or absorb all the information.
Type 2 diabetes is a complicated, labor-intensive chronic disease. Dietitians ask patients to change their eating habits, start an exercise program, monitor glucose, and learn a new medication regimen, and then write down all of this information in a diary. To manage diabetes optimally, RDs need to help clients interpret all this complex information and develop critical-thinking and problem-solving skills. Controlling diabetes becomes a balancing act between food intake, physical activity, and medications.
To achieve this balancing act, it’s important for RDs to teach clients and patients the value of self-monitoring their blood glucose, setting glucose goals before and after meals, and working with their health care providers to learn what medications they’re taking and to coordinate care.
Self-monitoring of blood glucose is a tool that can empower patients to take control of their disease. It provides valuable information to the health care team for timely adjustment of therapy, leading to better outcomes and quality of life. Type 2 diabetes is progressive and often requires ongoing assessment and adjustment of the treatment regimen, including repeated educational sessions about appropriate self-monitoring use and application.
Glucose Goal Setting
Every client and patient with type 2 diabetes is unique, and most have other health concerns such as hypertension, hypercholesterolemia, thyroid dysfunction, and perhaps early kidney disease at the time of diagnosis. So one size doesn’t fit all when setting glucose goals with patients. Therefore, it’s important to discuss individualized goals with the client’s health care provider.
Some issues to consider when setting glucose goals include the risk of hypoglycemia, age, health literacy, ability to comply with complex medication regimens, duration of diabetes, caregiver support, financial constraints, social and cultural issues, and avoiding the long-term complications of hyperglycemia. Evidence shows that early, aggressive control of newly diagnosed type 2 diabetes may help preserve beta-cell function. Less intense control is appropriate for older clients and those who already have significant vascular complications.
The American Diabetes Association guidelines for glucose goals in adults with type 2 diabetes include the following:
- fasting and premeal blood glucose of 70 to 130 mg/dL;
- one- to two-hour postprandial glucose of less than 180 mg/dL; and
- hemoglobin A1c level of less than 7% or a mean plasma glucose of 150 to 160 mg/dL
The American Association of Clinical Endocrinologists and the International Diabetes Federation agree on these recommendations:
- fasting blood glucose of less than 110 mg/dL;
- two-hour postprandial glucose of less than 140 mg/dL; and
- hemoglobin A1c level of 6.5% or less or mean plasma glucose of 140 mg/dL
Meal-Based Glucose Testing
The predominant focus of diabetes therapy has been on lowering hemoglobin A1c and controlling fasting plasma glucose levels to reduce microvascular complications (eg, neuropathy, nephropathy, retinopathy). There’s a growing body of evidence that suggests reducing postmeal glucose spikes is important for reaching hemoglobin A1c goals and preventing cardiovascular disease. Studies have linked high postprandial blood glucose and widely fluctuating glucose readings with increased inflammation, decreased blood vessel flexibility, increased oxidative damage, and decreased myocardial blood flow.
Clients may be testing only their fasting blood glucose, and those numbers may be in the desired range. But they spend up to eight or nine hours each day in the postprandial state. Studies presented in the International Diabetes Federation Guideline for Management of Postmeal Glucose have shown that postmeal glucose may represent 60% to 70% of the hemoglobin A1c value. Using creative testing patterns related to self-monitoring blood glucose can help identify how much carbohydrate to eat at meals and influence clients to make behavior changes.
Testing in Pairs
For example, testing glucose before a pancake-and-syrup breakfast, and then two hours afterward may show a much higher spike in glucose levels vs. a poached egg and toast meal. This is referred to as testing in pairs. This method of testing may be best used when a client is afraid to eat any carbohydrates or insists that a large serving of fries with lunch isn’t an issue.
Testing in pairs two or three times per week at different meal times can provide a wealth of information about the way each client responds to specific foods. When postprandial glucose is above the desired range, the RD can offer strategies to reduce carbohydrate intake at meals and discuss portion control.
Recent studies presented in the International Diabetes Federation Guideline for Management of Postmeal Glucose have shown that taking a 10- to 15-minute walk about one hour after each meal can reduce postmeal glucose and help those with type 2 diabetes meet their two-hour postprandial goals. It is good practice for clients to test their glucose levels before and after exercise, which gives them immediate positive feedback about the benefits of activity. After a month of testing in pairs, dietitians can help clients identify patterns and develop problem-solving skills. Clients with diabetes can use this information to adjust behavior and set realistic goals.
A Word About Medications
An RD may determine that clients are controlling carbohydrate intake at meals but still are experiencing high postmeal glucose levels. At this point, it’s important to communicate with their health care provider who manages and prescribes medication. Because diabetes is a progressive disease, clients may have lost some pancreatic function and need a new medication to meet glucose goals.
The food, physical activity, and blood glucose diary can provide valuable data for practitioners when choosing new medications or adjusting current therapy. The RD can help identify problematic hypoglycemia as well as postprandial hyperglycemia.
Importance of Examining the Numbers
Understandably, clients with diabetes don’t enjoy pricking themselves for the purpose of monitoring glucose if no one looks at the numbers. If RD’s show them the value and practical application of those important glucose readings, they likely will better appreciate the benefits of testing.