Key Points
- Individuals should be screened for metabolic risk, in five categories:
- Elevated waist circumference
- Decreased high density lipoprotein (HDL) cholesterol
- Elevated serum triglycerides
- Elevated blood pressure
- Elevated blood glucose
- Three or more categories being abnormal should alert the clinician to a patient’s increased risk for atherosclerotic cardiovascular disease (ASCVD) and type 2 diabetes mellitus (T2DM) (i.e., metabolic risk).
- Endocrine Society (ES) recommends that providers measure waist circumference as part of the initial evaluation. (Note, however, that this does not replace the measurement of weight.)
- Behavioral change should be the first-line therapy for prevention and should include changes to diet, increased exercise, and weight loss.
- Persons identified as having metabolic risk should undergo risk scoring to identify the 10-year risk for ASCVD.
Diagnosis
Definitions and Diagnosis
- 1.1: In individuals aged 40–75 years in the office setting, ES suggests providers screen for all five components of metabolic risk at the clinical visit. The finding of at least three components should specifically alert the clinician to a patient at metabolic risk (at higher risk for ASCVD and T2DM). (2|⊕◯◯◯).
Technical Remarks:
- The main components of metabolic risk as defined in this guideline are 1) elevated blood pressure, 2) increased waist circumference, 3) elevated fasting triglycerides, 4) low high-density lipoprotein-cholesterol (HDL-C), and 5) elevated glycemia.
- Elevated glycemia should be determined either by hemoglobin A1c, fasting glucose, or 2-hour glucose with a second test for confirmation using a new blood sample.
- Testing for additional biological markers (e.g., high-sensitivity C-reactive protein) associated with metabolic risk should be limited to subpopulations.
- This recommendation is specifically for adults aged 40–75 years, those for whom the interventions have the greatest impact and evidence for efficacy. This does not restrict screening for appropriate individuals outside of this age range, especially those who are younger.
- 1.2: In individuals aged 40–75 years in the office setting who do not yet have ASCVD or T2DM and already have at least one risk factor, we advise screening every 3 years for all five components of metabolic risk as part of the routine clinical examination. (Ungraded Good Practice Statement)
- 1.3: To establish metabolic risk in the general population, ES recommends that clinicians measure waist circumference as a routine part of the clinical examination. (1|⊕⊕⊕◯)
Technical Remarks:
- This measurement does not replace the routine measurement of weight or calculation of body mass index but can provide more focused information regarding risk for ASCVD and T2DM.
- The writing committee agrees that the cutoffs for elevated waist circumference should be ≥102 cm for men and ≥88 cm for women in Caucasian, African, Hispanic, and Native American populations.
- The writing committee agrees that the cutoffs for waist circumference in Asian populations (both East Asian and South Asian) should be ≥90 cm for men and ≥80 cm for women.
- 1.4: In individuals previously diagnosed with prediabetes, ES suggests testing at least annually for the presence of overt T2DM. (2|⊕⊕⊕◯)
Technical Remark:
- Prediabetes is defined in a variety of ways ( fasting plasma glucose, 2-hour plasma glucose following a 75-g oral glucose tolerance test, or hemoglobin A1c) by different organizations in different countries, and the writing committee does not endorse preferential use of one definition over another.
- 1.5: ES recommends that all individuals at metabolic risk in the office setting have their blood pressure measured annually and, if elevated, at each subsequent visit. (1|⊕⊕⊕⊕)
Technical Remarks:
- Blood pressure should be measured after five minutes of rest.
- Ambulatory and/or home blood pressure monitoring, if performed correctly, is recommended to confirm a diagnosis of hypertension after initial screening.
- 1.6: For individuals with elevated blood pressure >130 mmHg systolic and/or 80 mmHg diastolic who are not documented as having a history of hypertension, ES recommends confirmation of elevated blood pressure on a separate day within a few weeks or with a home blood pressure monitor.(1|⊕⊕⊕⊕)
Table 1. Criteria Proposed for Clinical Diagnosis of the Metabolic Syndrome or Metabolic Risk
| Clinical measure | AHA/NHLBIa Revised NCEP-ATPIII | Original International Diabetes Federationb | Harmonized Definitionc | Metabolic Risk (as defined in this guideline) |
|---|---|---|---|---|
| Age Range | None | None | None | 40–75 years |
| Selection criteria | 3 of the 5 below | Start with elevated waist circumference as below | 3 of the 5 below | 3 of the 5 below |
| Body weight/waist circumference (WC) | WC ≥102 cm in men or ≥88 cm in women (non-Asian origin) WC ≥90 cm in men or ≥80 cm in women (both East Asians and South Asians) | WC ≥94 cm in men or ≥80 cm in women (Europids, Sub-Saharan Africans, and Middle Eastern) WC ≥90 cm in men or ≥80 cm in women (both East Asians and South Asians; South and Central Americans) WC ≥85 cm in men or ≥90 cm in women (Japanese) plus any 2 of the following | Population and country-specific definitions determined by local organizations | WC ≥102 cm in men or ≥88 cm in women (non-Asian origin) WC ≥90 cm in men or ≥80 cm in women (both East Asians and South Asians) |
| Triglycerides (TGL) (fasting) | TGL ≥150 mg/dL (≥1.7 mmol/L) or on TGL Rx | TGL ≥150 mg/dL (≥1.7 mmol/L) or on TGL Rx | TGL ≥150 mg/dL (≥1.7 mmol/L) or on TGL Rx | TGL ≥150 mg/dL (≥1.7 mmol/L) or on TGL Rx |
| HDL cholesterol | HDL-C <40 mg/dL (<1.0 mmol/L) in men or <50 mg/dL (<1.3 mmol/L) in women or on HDL-C Rx | HDL-C <40 mg/dL (<1.0 mmol/L) in men or <50 mg/dL (<1.3 mmol/L) in women or on HDL-C Rx | HDL-C <40 mg/dL (<1.0 mmol/L) in men or <50 mg/dL (<1.3 mmol/L) in women or on HDL-C Rx | HDL-C <40 mg/dL (<1.0 mmol/L) in men or <50 mg/dL (<1.3 mmol/L) in women or on HDL-C Rx |
| Blood pressure | ≥130 mmHg systolic or ≥85 diastolic or on hypertension Rx | ≥130 mmHg systolic or ≥85 diastolic or on hypertension Rx | ≥130 mmHg systolic or ≥85 diastolic or on hypertension Rx | ≥130 mmHg systolic or ≥80 diastolic or on hypertension Rx |
| Glycemia | Fasting glucose ≥100 mg/dL (5.6 mmol/L) or drug treatment for elevated glucose | Fasting glucose ≥100 mg/dL (5.6 mmol/L) (includes diabetes) | Fasting glucose >100 mg/dL (5.6 mmol/L) or on drug treatment for elevated glucose | Fasting glucose ≥100 mg/dL (≥5.6 mmol/L) and <126 mg/dL (<7.0 mmol/L), OR 2 hr. OGTT ≥140 mg/dL (≥7.8 mmol/L), and <200 mg/dL (<11.0 mmol/L), OR HbA1c ≥5.7%–6.4% OR on drug treatment for elevated glucose without diagnosis of DM |
b Alberti KG, Zimmet P, Shaw J, International Diabetes Federation Epidemiology Task Force Consensus Group. The metabolic syndrome–a new worldwide definition. Lancet. 2005;366(9491):1059-1062.
c Alberti KG, Eckel RH, Grundy SM, et al. Harmonizing the metabolic syndrome: a joint interim statement of the International Diabetes Federation Task Force on Epidemiology and Prevention; National Heart, Lung, and Blood Institute; American Heart Association; World Heart Federation; International Atherosclerosis Society; and International Association for the Study of Obesity. Circulation. 2009;120(16):1640-1645.
Figure 1. Flow Chart for the Assessment and Treatment of Metabolic Risk
Figure 2. Measuring Waist Circumference According to NHANES III Protocol
Reproduced from NHLBI Obesity Education Initiative Expert Panel on the Identification, Evaluation, and Treatment of Obesity in Adults (US). Clinical Guidelines on the Identification, Evaluation, and Treatment of Overweight and Obesity in Adults: The Evidence Report. Bethesda (MD): National Heart, Lung, and Blood Institute; 1998 Sep. Available at: https://www.ncbi.nlm.nih.gov/books/NBK2004/figure/A237/ Table 2. Recommended Waist Thresholds to Define Abdominal Obesity
| Region/ethnicitya | Recommending organization | Waist circumference threshold for abdominal obesity |
|---|---|---|
| United States | AHA/NHLBI | ≥102 cm in men; ≥88 cm in womena |
| Europe/Europids | IDF | ≥94 cm in men; ≥80 cm in women |
| Asia | AHA/NHLBI IDF | ≥90 cm in men; ≥80 cm in womenb |
a AHA/NHLBI guidelines indicate that waist circumference thresholds of ≥94 cm in men and ≥80 cm in women are optional in persons who show clinical evidence of insulin resistance.
b In Japan, national recommendations for waist circumference thresholds for abdominal obesity are ≥85 cm in men and ≥90 cm in women.
Data derived from Alberti, K. G., P. Zimmet, J. Shaw and I. D. F. Epidemiology Task Force Consensus Group (2005). "The metabolic syndrome–a new worldwide definition." Lancet 366(9491): 1059-1062; Grundy, S. M., J. I. Cleeman, C. N. Merz, H. B. Brewer, Jr., L. T. Clark, D. B. Hunninghake, R. C. Pasternak, S. C. Smith, Jr. and N. J. Stone (2004). "Implications of recent clinical trials for the National Cholesterol Education Program Adult Treatment Panel III guidelines." Circulation 110(2): 227-239; and Examination Committee of Criteria for 'Obesity Disease' in Japan; Japan Society for the Study of Obesity. (2002). "New criteria for 'obesity disease' in Japan." Circ J 66(11): 987-992.
Table 3. Definitions of Prediabetes (Intermediate Glycemia)
| Prediabetes Category | ||||
|---|---|---|---|---|
| IFG | IGT | High Risk for DM by A1c | ||
| Organization | Fasting Glucose | 2-hour OGTT | Hemoglobin A1c | Comments |
| ADAa | 100–125 mg/dL (5.6–6.9 mmol/L) | 140–199 mg/dL (7.8–11.0 mmol/L) | 5.7–6.4% (39–46 mmol/mol) | Any one of the three is sufficient. |
| WHO 2011b | 110–125 mg/dL (6.1–6.9 mmol/L) | 140–199 mg/dL (7.8–11.0 mmol/L) | A1c is not recommended for diagnosis of intermediate glycemia. | |
| IEC 2003c | 100-125 mg/dL (6.1–6.9 mmol/L) | FPG lower threshold was revised downward from previous 1997 report to include more individuals. | ||
| IEC 2009d | 6.0–6.4% (42–46 mmol/mol) | Restricted to higher risk group than ADA definition for T2DM prevention. | ||
b World Health Organization. Use of glycated haemoglobin (HbA1c) in the diagnosis of diabetes mellitus: abbreviated report of a WHO consultation. 2011 www.who.int/diabetes/publications/diagnosis_diabetes2011/en/index.html.
c The Expert Committee on the Diagnosis and Classification of Diabetes Mellitus. Follow-up Report on the Diagnosis of Diabetes Mellitus. Diabetes Care 2003 Nov; 26(11): 3160-3167. https://doi.org/10.2337/diacare.26.11.3160.
d The International Expert Committee. International Expert Committee report on the role of the A1C assay in the diagnosis of diabetes. Diabetes Care. 2009; 32(7):1327-34.
