What is the recommended management plan for type 2 diabetes mellitus?

Management of Type 2 Diabetes Mellitus

Start metformin immediately at diagnosis alongside lifestyle modifications, then add an SGLT2 inhibitor for patients with cardiovascular disease, heart failure, or chronic kidney disease (eGFR ≥30), or add a GLP-1 receptor agonist for those needing additional glycemic control or weight loss. 1, 2

Initial Assessment and Glycemic Targets

• Measure HbA1c at diagnosis and target 7.0-8.0% for most adults, though individualize based on disease duration, life expectancy, and comorbidities 1, 2
• For patients with short disease duration, long life expectancy, and no significant cardiovascular disease, consider more stringent targets of 6.0-6.5% if achievable without hypoglycemia 1
• For patients with history of severe hypoglycemia, limited life expectancy, advanced complications, or extensive comorbidities, target 7.5-8.0% or slightly higher 1
• Monitor HbA1c every 3 months until target is achieved, then at least twice yearly 3

Lifestyle Interventions (Start Immediately)

Physical Activity

• Prescribe at least 150 minutes per week of moderate-intensity aerobic activity, spread over at least 3 days with no more than 2 consecutive days without exercise 1, 2
• Add resistance training at least twice weekly to improve insulin sensitivity 2
• Break up sedentary time with 5-minute activity breaks every hour 1, 2

Nutrition

• Refer for medical nutrition therapy with a registered dietitian to develop a personalized food plan 1
• Emphasize vegetables, fruits, whole grains, fiber, legumes, plant-based proteins, unsaturated fats, and nuts 1, 2
• Limit sodium intake to less than 2g per day 1, 2
• Avoid sugar-sweetened beverages including fruit juices 1
• For patients with chronic kidney disease not on dialysis, maintain protein intake at 0.8g/kg body weight/day 1, 2

Weight Management

• Target at least 5% weight loss for patients with overweight or obesity, as this produces meaningful improvements in glycemic control 1, 2
• Weight loss exceeding 10% early in disease course increases chance of remission 1, 3
• Achieve weight loss through 500-750 kcal/day energy deficit or provide 1,200-1,500 kcal/day for women and 1,500-1,800 kcal/day for men 1

Pharmacological Management Algorithm

First-Line Therapy (At Diagnosis)

• Start metformin immediately at diagnosis for all patients with eGFR ≥30 ml/min per 1.73 m² unless contraindicated 1, 2, 3
• Titrate to 1000mg twice daily or 850mg twice daily as tolerated 3
• For highly motivated patients with HbA1c <7.5%, lifestyle changes alone may be attempted for 3-6 months before starting metformin 1
• For patients with severe hyperglycemia (HbA1c ≥10-12%) or symptomatic hyperglycemia, consider starting insulin immediately 3, 4

Second-Line Therapy (Add to Metformin)

For patients with established cardiovascular disease, heart failure, or chronic kidney disease:

• Add SGLT2 inhibitor for patients with eGFR ≥30 ml/min per 1.73 m² (strong recommendation based on cardiovascular and renal benefits) 1, 2, 3, 5
• SGLT2 inhibitors reduce atherosclerotic cardiovascular disease by 12-26%, heart failure by 18-25%, and kidney disease progression by 24-39% over 2-5 years 5

For patients not at target with metformin and SGLT2i, or unable to use these medications:

• Add long-acting GLP-1 receptor agonist 1, 2, 3
• High-potency GLP-1 receptor agonists produce weight loss exceeding 5% in most patients, often exceeding 10% 1, 5
• Consider dual GIP/GLP-1 receptor agonists for enhanced weight loss (10-15% or more) 1, 3

Additional Therapy Options

• Dipeptidyl peptidase-4 inhibitors (DPP-4i) for patients unable to use GLP-1 receptor agonists 5
• Sulfonylureas for additional glycemic control, though associated with hypoglycemia risk and weight gain 1, 5
• Thiazolidinediones to improve insulin sensitivity, but monitor for fluid retention and heart failure 1, 5

Insulin Therapy

• Approximately one-third of patients with type 2 diabetes require insulin during their lifetime 5
• For patients not achieving targets with oral agents, start with basal insulin (insulin glargine) once daily at bedtime 1, 6
• Initial dosing: 10 units daily for insulin-naive patients, or 80% of previous NPH insulin dose for those switching 6
• Titrate basal insulin by 2-4 units every 3-4 days until fasting glucose consistently <130 mg/dL 4
• For severe hyperglycemia (HbA1c ≥10-12%), implement basal-bolus regimen with total daily insulin 0.8-1.0 units/kg/day 4

Diabetes Self-Management Education and Support (DSMES)

• Initiate DSMES at diagnosis with trained diabetes care and education specialists 1, 2, 3
• Provide DSMES annually, with changes in health status, and during transitions of care 1, 2, 3
• DSMES is as important as medication selection for achieving treatment goals 1

Cardiovascular Risk Management

• For patients with diabetes, hypertension, and albuminuria, initiate ACE inhibitor or ARB and titrate to highest approved tolerated dose 1
• Advise all patients who use tobacco to quit 1
• Comprehensive cardiovascular risk reduction must be a major focus of therapy 2

Monitoring and Follow-Up

• Check HbA1c every 3 months until target achieved, then at least twice yearly 3
• Monitor fasting and premeal glucose targeting <130 mg/dL and postprandial glucose <180 mg/dL 1
• Perform blood glucose monitoring at least 4 times daily (before meals and bedtime) for patients on intensive insulin regimens 4
• Follow up within 1-2 weeks after intensifying insulin therapy to assess response and adjust doses 4
• Screen for hypoglycemia, especially with intensified insulin regimens or in patients with renal/hepatic impairment 6

Common Pitfalls to Avoid

• Do not delay metformin initiation in patients with moderate hyperglycemia—start at diagnosis alongside lifestyle changes 1, 3
• Do not use sitagliptin (DPP-4i) in patients on multiple daily insulin injections—it provides minimal benefit in this setting 4
• Do not mix or dilute insulin glargine with any other insulin or solution 6
• Rotate injection sites to reduce risk of lipodystrophy and localized cutaneous amyloidosis 6
• Never share insulin pens or syringes between patients, even if needle is changed 6
• Monitor potassium levels in patients at risk when starting SGLT2 inhibitors or insulin 6
• Observe for fluid retention and heart failure when using thiazolidinediones, particularly in combination with insulin 6