What are the steps for managing type 2 diabetes mellitus (T2DM)?

Type 2 Diabetes Mellitus Management: Step-by-Step Algorithm

Step 1: Initial Assessment and Immediate Treatment Decision

Start metformin 500 mg daily alongside comprehensive lifestyle modifications immediately at diagnosis for all newly diagnosed T2DM patients, unless severe hyperglycemia is present. 1, 2

Initiate insulin therapy immediately (0.5 units/kg/day) if ANY of the following criteria are met: 1, 2, 3

• Ketosis or diabetic ketoacidosis present 1, 3
• Random blood glucose ≥250 mg/dL 1, 2, 3
• HbA1c ≥8.5% (some guidelines use >9% threshold) 1, 2, 3
• Unclear distinction between Type 1 and Type 2 diabetes 1, 3

For patients requiring immediate insulin, start basal insulin (NPH, insulin glargine, or insulin detemir) with or without prandial coverage, then transition to metformin-based therapy once glucose stabilizes. 2

Step 2: Metformin Titration Protocol

Increase metformin by 500 mg every 1-2 weeks to reach the ideal dose of 2000 mg daily in divided doses. 3 This gradual titration minimizes gastrointestinal side effects while achieving therapeutic dosing. 3

Step 3: Comprehensive Lifestyle Modifications (Initiated Simultaneously)

Physical Activity Prescription

Prescribe at least 150 minutes per week of moderate-intensity OR 75 minutes per week of vigorous-intensity aerobic exercise, combined with resistance training. 1, 2, 4

• Break up sedentary time with 5-minute activity breaks every hour 2
• Combine aerobic exercise with resistance training for optimal glycemic control 1, 2, 3
• Use the "talk test" to gauge intensity: during moderate activity, patients can talk but not sing; during vigorous activity, they cannot talk without pausing to catch their breath 3
• Provide written prescription specifying duration, intensity, and frequency 3

For pediatric patients (children and adolescents): prescribe at least 60 minutes daily of moderate-to-vigorous exercise, including muscle and bone strengthening activities at least 3 days per week. 3

Nutrition Intervention

Refer to a registered dietitian nutritionist with diabetes expertise at diagnosis for individualized medical nutrition therapy. 1, 2, 3

Implement Mediterranean, DASH, or vegetarian/vegan dietary patterns with the following specifications: 1, 2

• Focus on fiber-rich whole grains and avoid refined carbohydrates 1, 2, 3
• Reduce red meat consumption 1, 3
• Completely eliminate sugar-added beverages 1, 3
• Dietary fat should account for 20-30% of total calorie intake 5
• Carbohydrates should account for 50-65% of total calorie intake 5
• Protein intake should be approximately 0.8 g/kg/day (15-20% of total calories) for patients with normal renal function 5

Screen Time Management (Pediatric Patients)

Limit non-academic screen time to less than 2 hours per day and remove video screens/TVs from children's bedrooms. 3

Smoking Cessation

Advise every diabetic smoker to stop smoking immediately, set a quit date, and prescribe medications if necessary to assist with cessation. 5 Smoking has synergistic risks with diabetes, particularly for cardiovascular disease. 5

Step 4: Monitoring Protocol

Check HbA1c every 3 months until target is achieved (<7% for most patients), then at least twice yearly. 1, 2, 3

Implement finger-stick blood glucose monitoring for patients who: 1, 3

• Are taking insulin or medications with hypoglycemia risk 1, 3
• Are initiating or changing diabetes treatment regimen 1, 3
• Have not met treatment goals 1, 3
• Have intercurrent illnesses 1, 3

Step 5: Treatment Intensification at 3 Months

If HbA1c target is not achieved after 3 months on metformin, add a second agent based on comorbidities: 1, 2

For Patients with Heart Failure or Chronic Kidney Disease:

Add SGLT-2 inhibitor (e.g., empagliflozin). 1, 2 Empagliflozin has demonstrated cardiovascular mortality reduction (hazard ratio 0.62,95% CI 0.49-0.77) in patients with established cardiovascular disease. 6

Common adverse effects to counsel patients about: 6

• Urinary tract infections and genital mycotic infections 6
• Risk of ketoacidosis (instruct patients to check ketones if symptoms occur even with normal blood glucose) 6
• Hypotension risk (ensure adequate hydration) 6
• Acute kidney injury risk (temporarily discontinue during acute illness, fasting, or excessive fluid losses) 6

For Patients with Established ASCVD or High Cardiovascular Risk:

Add GLP-1 receptor agonist. 1, 2, 3 GLP-1 receptor agonists provide 10-15% weight loss or more and are particularly effective for patients with obesity. 1, 3

Contraindication: Family history of medullary thyroid cancer 1, 3

Step 6: Triple Therapy

If dual therapy fails to achieve HbA1c targets after 3 months, add a third agent with a different mechanism of action. 5 The Chinese guidelines recommend metformin plus two drugs with different mechanisms of action. 5

Step 7: Insulin Therapy for Advanced Disease

When triple oral therapy fails to achieve targets, initiate basal insulin added to existing oral agents, titrating based on fasting glucose. 5, 2

Options include: 5

• Metformin + basal insulin + prandial insulin 5
• Multiple daily injections of premixed insulin 5

Many patients initially requiring insulin can be gradually weaned and subsequently managed with metformin and lifestyle modification once glucose stabilizes. 3

Step 8: Weight Management Strategy

Target at least 5% weight loss for clinical benefits, with substantial weight loss (>10%) early in disease course increasing chance of remission. 1

Consider metabolic surgery for patients without sufficient response to non-surgical weight loss interventions, particularly early in disease course, performed in high-volume centers with experienced multidisciplinary teams. 1

Step 9: Diabetes Self-Management Education

Provide comprehensive diabetes self-management education (DSMES) at diagnosis, annually, with changes in health status, and with transitions of care. 1, 3

Establish SMART goals (Specific, Measurable, Attainable, Relevant, Time-based) for behavior change rather than non-specific recommendations. 1

Step 10: Cardiovascular Risk Factor Management

Aggressively manage all cardiovascular risk factors concurrently with glucose control, including hypertension, dyslipidemia, and smoking cessation. 2

Initiate statin therapy for most patients >40 years and antiplatelet therapy when indicated. 2

Common Pitfalls to Avoid

• Do not delay insulin therapy in patients meeting criteria for immediate insulin initiation—this can lead to prolonged hyperglycemia and increased complications 1, 2
• Do not continue metformin monotherapy beyond 3 months if HbA1c targets are not met—early intensification improves long-term outcomes 1, 2
• Do not prescribe excessive protein intake (>1.3 g/kg/day) as this is associated with increased proteinuria, decreased renal function, and increased cardiovascular and mortality risk 5
• Do not overlook the importance of written exercise prescriptions—adherence improves when patients receive specific, individualized activity plans 3
• Do not forget to temporarily discontinue SGLT-2 inhibitors during acute illness, fasting, or excessive fluid losses to prevent acute kidney injury 6