Assessment of Glycemic Status
How to Assess
A1C measurement- Continuous glucose monitoring (CGM) using appropriate metrics (e.g., time in range [TIR], time above range [TAR], and time below range [TBR])
When to Assess Glycemic Status With an A1C Test
Glucose Assessment via CGM: The Ambulatory Glucose Profile (AGP) Report
Correlation Between A1C and Estimated Average Glucose (eAG)
| A1C (%) | mg/dL | mmol/L |
|---|---|---|
| 5 | 97 (76–120) | 5.4 (4.2–6.7) |
| 6 | 126 (100–152) | 7.0 (5.5–8.5) |
| 7 | 154 (123–185) | 8.6 (6.8–10.3) |
| 8 | 183 (147–217) | 10.2 (8.1–12.1) |
| 9 | 212 (170–249) | 11.8 (9.4–13.9) |
| 10 | 240 (193–282) | 13.4 (10.7–15.7) |
| 11 | 269 (217–314) | 14.9 (12.0–17.5) |
| 12 | 298 (240–347) | 16.5 (13.3–19.3) |
| A1C (%) | mg/dL | mmol/L |
|---|---|---|
| 5 | 97 (76–120) | 5.4 (4.2–6.7) |
| 6 | 126 (100–152) | 7.0 (5.5–8.5) |
| 7 | 154 (123–185) | 8.6 (6.8–10.3) |
| 8 | 183 (147–217) | 10.2 (8.1–12.1) |
| 9 | 212 (170–249) | 11.8 (9.4–13.9) |
| 10 | 240 (193–282) | 13.4 (10.7–15.7) |
| 11 | 269 (217–314) | 14.9 (12.0–17.5) |
| 12 | 298 (240–347) | 16.5 (13.3–19.3) |
A calculator for converting A1C results into eAG, in either mg/dL or mmol/L, is available at professional.diabetes.org/eAG. Data in parentheses are a 95% CI. Adapted from Nathan DM, Kuenen J, Borg R, Zheng H, Schoenfeld D; A1c-Derived Average Glucose Study Group. Translating the A1C assay into estimated average glucose values. Diabetes Care 2008;31:1473–1478.
Setting and Modifying Glycemic Goals
Glycemic goals should be individualized and periodically reevaluated.
Individualized A1C Goals for Nonpregnant Adults
Modifying Factors
| Favor more stringent goal | Favor less stringent goal |
|---|---|
| Short diabetes duration | Long diabetes duration |
| Low hypoglycemia risk | High hypoglycemia risk |
| Low treatment risks and burdens | High treatment risks and burdens |
| Pharmacotherapy with cardiovascular, kidney, weight, or other benefits | Pharmacotherapy without nonglycemic benefits |
| No cardiovascular complications | Established cardiovascular complications |
| Few or minor comorbidities | Severe, life-limiting comorbidities |
| Favor more stringent goal | Favor less stringent goal |
|---|---|
| Short diabetes duration | Long diabetes duration |
| Low hypoglycemia risk | High hypoglycemia risk |
| Low treatment risks and burdens | High treatment risks and burdens |
| Pharmacotherapy with cardiovascular, kidney, weight, or other benefits | Pharmacotherapy without nonglycemic benefits |
| No cardiovascular complications | Established cardiovascular complications |
| Few or minor comorbidities | Severe, life-limiting comorbidities |
Select the glycemic goal based on individual health and function as described at the top of the figure.
Consider modifying to a more or less stringent goal according to the factors listed in the table. Older adults are classified as healthy (few coexisting chronic illnesses, intact cognitive and functional status), as having complex/intermediate health (multiple coexisting chronic illnesses, two or more instrumental impairments to activities of daily living, or mild to moderate cognitive impairment), or as having very complex/poor health (long-term care or end-stage chronic illnesses, moderate to severe cognitive impairment, or two or more impairments to activities of daily living). Select glycemic goals that avoid symptomatic hypoglycemia and hyperglycemia in all individuals. Consider individuals’ resources and support systems to safely achieve glycemic goals. Incorporate the preferences and goals of people with diabetes through shared decision-making.
Hyperglycemic Crises: Diagnosis, Management, and Prevention
Diabetic ketoacidosis (DKA) and the hyperglycemic hyperosmolar state (HHS) are serious, acute, and life-threatening hyperglycemic emergencies in individuals with diabetes that incur substantial morbidity, mortality, and costs.
Clinicians should review history of hyperglycemic crises (e.g., DKA and HHS) at every clinical encounter for all individuals with diabetes at risk for these events.
Provide structured education on the recognition, prevention, and management of hyperglycemic crisis. Individuals who have experienced DKA or HHS should be screened for social determinants of health and referred to appropriate health care and/or community services to mitigate these barriers to care.
Individuals at risk for DKA should be counseled on its early signs and symptoms and educated on timely self-management of hyperglycemia and ketonemia (“sick day advice”). Clinicians should provide detailed instructions on insulin dose adjustments in the setting of illness or fasting to prevent DKA occurrence and worsening.
Risk Factors for Hyperglycemic Crises
| Type 1 diabetes/absolute insulin deficiency |
| Presence of other chronic health conditions (particularly in people with type 2 diabetes) |
| Younger age |
| Presence of behavioral health conditions (e.g., depression, bipolar disorder, and eating disorders) |
| Prior history of hyperglycemic crises |
| Alcohol and/or substance use |
| Prior history of hypoglycemic crises |
| High A1C level |
| Presence of other diabetes complications |
| Social determinants of health |
| Type 1 diabetes/absolute insulin deficiency |
| Presence of other chronic health conditions (particularly in people with type 2 diabetes) |
| Younger age |
| Presence of behavioral health conditions (e.g., depression, bipolar disorder, and eating disorders) |
| Prior history of hyperglycemic crises |
| Alcohol and/or substance use |
| Prior history of hypoglycemic crises |
| High A1C level |
| Presence of other diabetes complications |
| Social determinants of health |
Data are from McCoy RG, Galindo RJ, Swarna KS, et al. Sociodemographic, clinical, and treatment-related factors associated with hyperglycemic crises among adults with type 1 or type 2 diabetes in the US From 2014 to 2020. JAMA Netw Open 2021;4:e2123471; Gibb FW, Teoh WL, Graham J, Lockman KA. Risk of death following admission to a UK hospital with diabetic ketoacidosis. Diabetologia 2016;59:2082–2087; Randall L, Begovic J, Hudson M, et al. Recurrent mental ketoacidosis in inner-city minority patients: behavioral, socioeconomic, and psychosocial factors. Diabetes Care 2011;34: 1891–1896; and Thomas M, Harjutsalo V, Feodoroff M, Forsblom C, Gordin D, Groop P-H. The long-term incidence of hospitalization for ketoacidosis in adults with established T1D—a prospective cohort study. J Clin Endocrinol Metab 2020;105:dgz003
Diagnostic Criteria for DKA and HHS
Hyperglycemic crisis should be considered in all individuals presenting with polyuria, polydipsia, weight loss, vomiting, dehydration, and change in cognitive state. All criteria must be met to establish these diagnoses. One-third of hyperglycemic emergencies have a hybrid DKA-HHS presentation.
| DKA | |
|---|---|
| Diabetes/hyperglycemia | Glucose ≥200 mg/dL (11.1 mmol/L) or prior history of diabetes |
| Ketosis | β-Hydroxybutyrate concentration ≥3.0 mmol/L or urine ketone strip 2+ or greater |
| Metabolic acidosis | pH <7.3 and/or bicarbonate concentration <18 mmol/L |
| DKA | |
|---|---|
| Diabetes/hyperglycemia | Glucose ≥200 mg/dL (11.1 mmol/L) or prior history of diabetes |
| Ketosis | β-Hydroxybutyrate concentration ≥3.0 mmol/L or urine ketone strip 2+ or greater |
| Metabolic acidosis | pH <7.3 and/or bicarbonate concentration <18 mmol/L |
| HHS | |
|---|---|
| Hyperglycemia | Plasma glucose ≥600 mg/dL (33.3 mmol/L) |
| Hyperosmolarity | Calculated effective serum osmolality >300 mOsm/kg (calculated as [2×Na+ (mmol/L) + glucose (mmol/L)] or total serum osmolality >320 mOsm/kg [2×Na+ (mmol/L) + glucose (mmol/L) + urea (mmol/L)] |
| Absence of significant ketonemia | β-Hydroxybutyrate concentration <3.0 mmol/L OR urine ketone strip less than 2+ |
| Absence of acidosis | pH ≥7.3 and bicarbonate concentration ≥15 mmol/L |
| HHS | |
|---|---|
| Hyperglycemia | Plasma glucose ≥600 mg/dL (33.3 mmol/L) |
| Hyperosmolarity | Calculated effective serum osmolality >300 mOsm/kg (calculated as [2×Na+ (mmol/L) + glucose (mmol/L)] or total serum osmolality >320 mOsm/kg [2×Na+ (mmol/L) + glucose (mmol/L) + urea (mmol/L)] |
| Absence of significant ketonemia | β-Hydroxybutyrate concentration <3.0 mmol/L OR urine ketone strip less than 2+ |
| Absence of acidosis | pH ≥7.3 and bicarbonate concentration ≥15 mmol/L |
Adapted from Umpierrez GE, Davis GM, ElSayed NA, et al. Hyperglycemic crises in adults with diabetes: a consensus report. Diabetes Care 2024;47:1257–1275
Hypoglycemia Assessment, Prevention, and Treatment
Hypoglycemia is categorized into three levels based on blood glucose concentrations and symptom severity. Level 1 is glucose <70 mg/dL (<3.9 mmol/L) but ≥54 mg/dL (≥3.0 mmol/L). Level 2 is glucose <54 mg/dL (<3.0 mmol/L). Level 3 is a severe event characterized by altered mental and/or physical status requiring assistance for treatment of hypoglycemia, irrespective of glucose level.
| Assessment and medication selection | |
|---|---|
| Review hypoglycemia history at every clinical encounter in all at-risk individuals. |
| Screen for impaired hypoglycemia awareness at least annually and when clinically appropriate in all at-risk individuals. |
| Consider hypoglycemia risk when selecting diabetes medications and setting glycemic goals. |
| Assessment and medication selection | |
|---|---|
| Review hypoglycemia history at every clinical encounter in all at-risk individuals. |
| Screen for impaired hypoglycemia awareness at least annually and when clinically appropriate in all at-risk individuals. |
| Consider hypoglycemia risk when selecting diabetes medications and setting glycemic goals. |
| Prevention and management of hypoglycemia | |
|---|---|
| Use CGM for individuals at high risk for hypoglycemia. |
| Glucose is the preferred treatment for hypoglycemia in conscious individuals with glucose levels <70 mg/dL (<3.9 mmol/L), although any form of glucose-containing carbohydrate can be used. Avoid using foods or beverages high in fat and/or protein for initial treatment. Re-test and re-treat, if needed, after 15 minutes. |
| Prescribe glucagon for all individuals taking insulin or at high risk for hypoglycemia and provide caregivers with education on its use and proper storage. |
| Offer structured education on hypoglycemia prevention and treatment to all individuals taking insulin or at high risk for hypoglycemia. |
| Upon occurrence of one or more episodes of level 2 or level 3 hypoglycemia, promptly reevaluate the treatment plan, including considering whether to deintensify or switch medications. |
| Refer individuals with impaired hypoglycemia awareness to a trained health care professional for evidence-based intervention to improve hypoglycemia awareness. |
| Conduct ongoing assessments of cognitive function, ensuring extra caution and support for hypoglycemia if impaired or declining cognition is identified. |
| Prevention and management of hypoglycemia | |
|---|---|
| Use CGM for individuals at high risk for hypoglycemia. |
| Glucose is the preferred treatment for hypoglycemia in conscious individuals with glucose levels <70 mg/dL (<3.9 mmol/L), although any form of glucose-containing carbohydrate can be used. Avoid using foods or beverages high in fat and/or protein for initial treatment. Re-test and re-treat, if needed, after 15 minutes. |
| Prescribe glucagon for all individuals taking insulin or at high risk for hypoglycemia and provide caregivers with education on its use and proper storage. |
| Offer structured education on hypoglycemia prevention and treatment to all individuals taking insulin or at high risk for hypoglycemia. |
| Upon occurrence of one or more episodes of level 2 or level 3 hypoglycemia, promptly reevaluate the treatment plan, including considering whether to deintensify or switch medications. |
| Refer individuals with impaired hypoglycemia awareness to a trained health care professional for evidence-based intervention to improve hypoglycemia awareness. |
| Conduct ongoing assessments of cognitive function, ensuring extra caution and support for hypoglycemia if impaired or declining cognition is identified. |
