What are the recommended treatments for diabetes?

Recommended Treatments for Diabetes

Metformin should be initiated at or soon after diagnosis as first-line therapy for type 2 diabetes, starting at 500 mg daily and titrating up to 2000 mg daily in divided doses, combined with structured lifestyle modifications including at least 150 minutes weekly of moderate-intensity physical activity and a 5-7% weight loss goal. 1, 2

Type 1 Diabetes Management

Insulin therapy is the cornerstone of type 1 diabetes treatment:

• Use multiple daily injections (3-4 injections per day of basal and prandial insulin) or continuous subcutaneous insulin infusion (pump therapy) 3
• Match prandial insulin doses to carbohydrate intake, premeal blood glucose levels, and anticipated physical activity 3
• Insulin analogs are preferred over human insulins because they reduce hypoglycemia risk while achieving equivalent glycemic control 3
• For patients with frequent nocturnal hypoglycemia or hypoglycemia unawareness, sensor-augmented pumps with low glucose threshold suspend features should be considered 3

Type 2 Diabetes Management Algorithm

Initial Treatment Approach

Start metformin immediately unless contraindicated:

• Begin at 500 mg daily, increase by 500 mg every 1-2 weeks up to maximum 2000 mg daily in divided doses 1, 2
• Metformin decreases hepatic glucose output and improves peripheral insulin sensitivity, and has demonstrated mortality reduction in type 2 diabetes 4
• Concurrent lifestyle modifications are mandatory, not optional 2

Exceptions Requiring Insulin First-Line

Bypass metformin and initiate insulin immediately in these situations:

• Ketosis or diabetic ketoacidosis present 1, 2
• Random blood glucose ≥250 mg/dL 1, 2
• HbA1c >9% (>75 mmol/mol) 1, 2
• Severe hyperglycemia with catabolism 1, 2
• Symptomatic diabetes with polyuria, polydipsia, and weight loss 1, 2

Treatment Intensification When Metformin Monotherapy Fails

Add a second agent if HbA1c target is not achieved after 3 months on maximum tolerated metformin dose:

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

• Add SGLT-2 inhibitor or GLP-1 receptor agonist as second-line therapy 1, 5
• These medications provide 12-26% cardiovascular risk reduction, 18-25% heart failure risk reduction, and 24-39% kidney disease risk reduction over 2-5 years 5

For patients without cardiovascular/kidney comorbidities, choose from:

• SGLT-2 inhibitors 1
• GLP-1 receptor agonists (high-potency agents produce >5% weight loss in most patients, often exceeding 10%) 1, 5
• DPP-4 inhibitors 1, 2
• Sulfonylureas 1, 2
• Thiazolidinediones 1, 2
• Basal insulin 1

Insulin Therapy for Type 2 Diabetes

When triple therapy fails to achieve glycemic targets:

• Initiate basal insulin at 0.5 units/kg/day 2
• Titrate every 2-3 days based on blood glucose monitoring 2
• If basal insulin alone is insufficient despite dose escalation, add prandial insulin 2
• Approximately one-third of type 2 diabetes patients require insulin during their lifetime 5

Lifestyle Modifications (Essential for All Diabetes Types)

Physical Activity Requirements

• Minimum 150 minutes per week of moderate-intensity aerobic activity 1, 4
• Reduce sedentary time throughout the day 1
• Resistance training at least twice weekly 1
• Physical activity reduces HbA1c by 0.4-1.0% and improves cardiovascular risk factors 5

Nutrition Therapy

• Focus on nutrient-dense, high-quality foods while decreasing calorie-dense, nutrient-poor foods 1
• Reduce saturated fat to <10% of energy intake, potentially <7% for those with elevated LDL cholesterol 1
• Limit sodium to 2,400 mg (100 mmol) daily, or 6,000 mg sodium chloride per day 1
• Include whole grains, fruits, vegetables, and low-fat milk 3
• Structured programs emphasizing these changes produce 5-7% long-term weight loss 3, 1

Glycemic Targets and Monitoring

Target HbA1c <7% for most adults, with more stringent targets (<6.5%) for selected individuals without significant hypoglycemia risk: 1

• Monitor HbA1c every 3 months until target achieved, then at least twice yearly 1, 2
• Adjust therapy when targets are not met—avoid clinical inertia 2
• Home blood glucose monitoring utility is questionable except for patients on multiple insulin injections 4
• Consider continuous glucose monitoring for patients requiring frequent blood glucose checks 2

Cardiovascular Risk Management

Lipid Management

Statin therapy is recommended for most patients with diabetes aged 40 years or older: 3

• Moderate-intensity statin for most patients 3
• High-intensity statin for those with established cardiovascular disease 3
• Ezetimibe can be added to moderate-intensity statin therapy for patients with recent acute coronary syndrome and LDL ≥50 mg/dL 3
• Combination statin plus fibrate is generally not recommended, though fenofibrate may be considered for men with triglycerides ≥204 mg/dL and HDL ≤34 mg/dL 3

Antiplatelet Therapy

• Aspirin 75-162 mg daily for primary prevention in patients with 10-year cardiovascular risk >10% 3
• Aspirin should not be used for primary prevention in low-risk patients (10-year risk <5%) 3
• Clopidogrel 75 mg daily for patients with documented aspirin allergy and established cardiovascular disease 3

Kidney Disease Screening

Annual screening for diabetic kidney disease is mandatory: 3

• Monitor serum creatinine/eGFR and serum potassium when ACE inhibitors or ARBs are used 3
• Intensive diabetes management delays onset and progression of albuminuria and reduced eGFR 3

Critical Pitfalls to Avoid

• Never delay treatment intensification when glycemic targets are not met—this clinical inertia worsens long-term outcomes 2
• Adjust medications during acute illness or procedures to prevent complications 2
• Educate patients on hypoglycemia risk factors: fasting for tests/procedures, during/after exercise, and during sleep 1
• Treat hypoglycemia with 15-20g rapid-acting glucose 1
• Monitor for metformin side effects: approximately 3% experience metallic taste initially; rarely causes hypoglycemia alone but risk increases with alcohol, inadequate food intake, or combination with other glucose-lowering agents 6

Long-Term Outcomes Evidence

Intensive glucose-lowering strategies (HbA1c <7%) demonstrate sustained benefits decades after initial treatment:

• 3.5% absolute reduction in microvascular disease (retinopathy, nephropathy) 5
• 3.3-6.2% absolute reduction in myocardial infarction 5
• 2.7-4.9% absolute reduction in mortality 20 years after trial completion 5