Initial Management Recommendations for Diabetes Mellitus
For patients with newly diagnosed diabetes mellitus, initial management should include lifestyle modifications with diabetes self-management education and support, individualized medical nutrition therapy, and at least 150 minutes of moderate-intensity aerobic activity per week, along with metformin as first-line pharmacological therapy for type 2 diabetes if not contraindicated. 1, 2
Type 2 Diabetes Initial Management
Lifestyle Modifications
- All patients should participate in diabetes self-management education and support to develop skills for diabetes self-care 1
- Physical activity recommendations include at least 150 minutes of moderate-intensity aerobic activity weekly, reduced sedentary time, and resistance training at least twice weekly 1, 2
- Individualized medical nutrition therapy, preferably provided by a registered dietitian, should focus on healthy eating patterns with nutrient-dense foods while reducing calorie-dense, nutrient-poor foods 1, 2
- For overweight or obese patients, counseling to lose at least 5% of body weight is recommended 1, 3
Pharmacological Therapy
- Metformin is the preferred initial pharmacological agent (A rating) for type 2 diabetes if not contraindicated 1
- Start metformin at a low dose and gradually increase to an ideal maximum dose of 2000 mg daily in divided doses 3, 4
- Metformin is recommended due to its efficacy, safety, low cost, and potential cardiovascular benefits 1, 2
- Metformin can be continued in patients with declining renal function down to a GFR of 30-45 mL/min, though the dose should be reduced 1
Special Circumstances Requiring Insulin First
- Insulin therapy should be initiated instead of metformin as first-line treatment in patients with:
Treatment Intensification
- When monotherapy with metformin at maximum tolerated dose does not achieve or maintain the HbA1c target over 3 months, a second agent should be added 1
- Options for second-line therapy include:
- Selection of second-line agent should be based on patient factors, disease characteristics, drug properties, and patient preferences 3
- Initial dual-regimen combination therapy should be considered when HbA1c is ≥9% to achieve glycemic control more quickly 1
Type 1 Diabetes Initial Management
- Most patients with type 1 diabetes should be treated with multiple-dose insulin injections (≥3 injections daily) or continuous subcutaneous insulin infusion 1
- Insulin analogs are recommended to reduce hypoglycemia risk 1
- Education on matching prandial insulin doses to carbohydrate intake, preprandial blood glucose levels, and anticipated activity level is essential 1
- Continuous glucose monitoring systems can significantly reduce severe hypoglycemia risk 1, 2
- Consider screening for autoimmune diseases (e.g., thyroid dysfunction, celiac disease) as appropriate 1
Monitoring and Follow-up
- HbA1c should be monitored every 3 months until target is reached, then at least twice yearly 2
- A reasonable HbA1c goal for most adults is <7%, with more stringent targets (such as <6.5%) for selected individuals if they can be achieved without significant hypoglycemia 1, 2
- For children and adolescents with type 2 diabetes, a reasonable A1c goal is <7%, with more stringent goals (<6.5%) appropriate for selected individuals 1
Common Pitfalls and Caveats
- Delaying treatment intensification when glycemic targets are not met (clinical inertia) should be avoided 3
- Metformin rarely causes hypoglycemia by itself, but hypoglycemia can occur if patients don't eat enough, drink alcohol, or take other glucose-lowering medications 4
- Patients with hypoglycemia unawareness should temporarily increase their glycemic targets to partially reverse this condition and reduce future risk 2
- Avoid aggressively targeting near-normal HbA1c levels in patients with advanced disease where such targets cannot be safely reached 2
- Medications should be adjusted during periods of acute illness or procedures 3