Diagnosis and Management of Diabetes

Diagnostic Criteria

The American Diabetes Association recommends diagnosing diabetes using any of the following criteria: fasting plasma glucose ≥126 mg/dL, HbA1c ≥6.5%, random plasma glucose ≥200 mg/dL with classic symptoms of hyperglycemia, or 2-hour plasma glucose ≥200 mg/dL during a 75-g oral glucose tolerance test 1, 2, 3
The American College of Physicians suggests that HbA1c testing has limitations in conditions affecting erythrocyte turnover and hemoglobin variants, which must be considered when interpreting results 4

The American Diabetes Association states that Type 1 diabetes accounts for approximately 5% of cases and is defined by the presence of one or more autoimmune markers 3, 5
The American Association of Clinical Endocrinologists notes that Type 2 diabetes accounts for 85-95% of cases and results from insulin resistance combined with inadequate insulin secretion 2, 6

The American Diabetes Association recommends that for patients with severe hyperglycemia or ketosis, initiate insulin therapy immediately 7, 8, 9
The American College of Physicians suggests that for all other newly diagnosed Type 2 diabetes patients, begin with lifestyle modifications plus metformin 10, 11, 9

The Academy of Nutrition and Dietetics recommends medical nutrition therapy, preferably provided by a registered dietitian, emphasizing nutrient-dense, high-quality foods while decreasing calorie-dense, nutrient-poor foods 11, 9
The American College of Sports Medicine suggests a physical activity plan of at least 150 minutes of moderate-intensity aerobic activity per week, reduced sedentary time, and resistance training at least twice per week 11, 9

The American Diabetes Association recommends a reasonable HbA1c goal for most adults is <7%, with more stringent targets for selected individuals 9
The American Association of Clinical Endocrinologists suggests HbA1c monitoring frequency of every 3 months until target is reached, then at least twice yearly if stable and meeting goals 3, 5, 4, 9

The American Diabetes Association recommends that if monotherapy with metformin at maximum tolerated dose does not achieve or maintain HbA1c target over 3 months, add a second agent 10, 9
The American College of Physicians suggests options for second-line therapy include SGLT-2 inhibitors, GLP-1 receptor agonists, thiazolidinediones, DPP-4 inhibitors, and basal insulin 7, 8

The American Diabetes Association recommends that most patients with Type 1 diabetes should be treated with multiple-dose insulin injections or continuous subcutaneous insulin infusion 10, 11, 9
The American Association of Clinical Endocrinologists suggests insulin analogues should be used to reduce hypoglycemia risk 10, 11

The American Diabetes Association recommends that hypoglycemia be treated with 15-20g of rapid-acting glucose, and confirm blood glucose reversal with SMBG after 15 minutes 11, 9
The American College of Physicians suggests that patients at risk for severe hypoglycemia should be prescribed glucagon, and close contacts should be instructed on administration 11