Full Guideline: Primary Prevention of ASCVD and T2DM in Patients at Metabolic Risk
JCEM | September 2019 (online July 2019)
James L. Rosenzweig (Chair), George L. Bakris, Lars F. Berglund, Marie-France Hivert, Edward S. Horton, Rita R. Kalyani, M. Hassan Murad, Bruno L. Vergès
The 2019 guideline on metabolic risk:
- Updates the previous recommendations on this topic from the 2008 guideline – particularly those on elevated lipids and blood pressure – to reflect more recent data.
- Emphasizes measures to identify and reduce the risk of ASCVD and T2DM, rather than defining the metabolic syndrome as a clinical entity.
- Focuses on adults between 40 and 75 years of age, for whom a higher quality of evidence exists than for other age groups, thus accruing the greatest impact.
Resources
Essential Points
- Individuals should be screened for metabolic risk, in five categories:
- Elevated waist circumference
- Decreased 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 ASCVD and DM (i.e., metabolic risk).
- We recommend 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.
List of Recommendations
+ 1.0 Definitions and Diagnosis
- 1.1 In individuals aged 40–75 years in the office setting, we suggest 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 atherosclerotic cardiovascular disease and type 2 diabetes mellitus). (2|⊕⚪⚪⚪)
Technical Remarks:
-
The main components of metabolic risk as defined in this guideline are:
- elevated blood pressure
- increased waist circumference
- elevated fasting triglycerides
- low high-density lipoprotein-cholesterol, and
- 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 atherosclerotic cardiovascular disease or type 2 diabetes mellitus 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, we recommend 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 atherosclerotic cardiovascular disease and type 2 diabetes mellitus.
- 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, we suggest testing at least annually for the presence of overt type 2 diabetes mellitus. (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 We recommend 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 above 130 mmHg systolic and/or 80 mmHg diastolic who are not documented as having a history of hypertension, we recommend confirmation of elevated blood pressure on a separate day within a few weeks or with a home blood pressure monitor. (1|⊕⊕⊕⊕)
+ 2.0 Lifestyle and Behavioral Therapy
- 2.1 In individuals at metabolic risk, we recommend that lifestyle modification be first-line therapy. (1|⊕⊕⊕⊕)
Technical Remark:
- The writing committee believes that primary care providers, endocrinologists, geriatricians and cardiologists should initiate discussions about the importance of adopting a healthy lifestyle with all individuals at metabolic risk. These and other relevant providers should encourage individuals to join comprehensive programs led by trained health professionals which support the adoption of healthy lifestyles, including diet and physical activity, aiming for moderate but sustained weight loss.
- 2.2 For individuals at metabolic risk with excess weight (defined by body mass index and/or waist circumference), we recommend that comprehensive programs to support the adoption of a healthy lifestyle should aim to achieve a weight loss of ≥5% of initial body weight over the first year. (1|⊕⊕⊕⊕)
Technical Remark:
- Maintenance of weight loss by adoption of sustainable healthy behaviors should be encouraged with continuing support of primary providers and/or extended programs.
- 2.3 In individuals at metabolic risk, we recommend prescribing a cardiovascular-healthy diet. (1|⊕⊕⊕⚪)
Technical Remarks:
- Providers can offer dietary recommendations based on common components of healthy cardiovascular dietary patterns to all individuals at metabolic risk.
- Specific dietary changes according to individual risk profiles could be supported with the help of a nutrition specialist in addition to the primary care provider.
- 2.4 In individuals at metabolic risk, we recommend prescribing daily physical activity, such as brisk walking, and reduction in sedentary time. (1|⊕⊕⊕⚪)
Technical Remark:
- Providers should encourage all individuals at metabolic risk to adopt an active lifestyle by walking and reducing the amount of time in sedentary activities. Structured activity programs may be added with the help of an exercise specialist for appropriate individuals.
+ 3.0 Medical and Pharmacological Therapy
Risk Assessment and Evaluation
- 3.1 In individuals identified as having metabolic risk, we recommend global assessment of 10-year risk for either coronary heart disease or atherosclerotic cardiovascular disease to guide the use of medical or pharmacological therapy. (1|⊕⊕⊕⚪)
Technical Remarks:
- Global risk assessment includes the use of one of the established cardiovascular risk equations.
- Elevated low-density lipoprotein is indicative of cardiovascular risk.
- 3.2 In individuals with low-density lipoprotein cholesterol ≥190 mg/dl (4.9 mmol/L) or triglycerides ≥500 mg/dl (<5.6 mmol/L), we recommend that, before considering the diagnosis of primary hyperlipidemia, practitioners should rule out secondary causes of hyperlipidemia. If a secondary cause can be excluded, primary hyperlipidemia should be suspected. (1|⊕⊕⊕⚪)
Technical Remarks:
- Examples of secondary causes of hyperlipidemia include untreated hypothyroidism, nephrotic syndrome, renal failure, cholestasis, acute pancreatitis, pregnancy, polycystic ovarian disease, excess alcohol use, treatment with estrogens/oral contraceptives, antipsychotic agents, glucocorticoids, cyclosporine, protease inhibitors, retinoids, and beta blockers.
- 3.3 In individuals 40–75 years of age with low-density lipoprotein-cholesterol ≥190 mg/dl (≥5.9 mmol/L), we recommend high-intensity statin therapy to achieve a low-density lipoprotein-cholesterol reduction of ≥50%. (1|⊕⊕⊕⚪)
- 3.4 In individuals 40–75 years of age with low-density lipoprotein-cholesterol 70–189 mg/dl (1.8-4.9 mmol/L) we recommend a 10-year risk for atherosclerotic cardiovascular disease should be calculated. (1|⊕⊕⊕o)
- 3.4.1 In individuals 40–75 years of age without diabetes and a 10-year risk ≥7.5%, we recommend high-intensity statin therapy either to achieve a low-density lipoprotein-cholesterol goal <100 mg/dl (<2.6 mmol/L) or a low-density lipoprotein-cholesterol reduction of ≥50%. (1|⊕⊕⊕⚪)
- 3.4.2 In individuals 40–75 years of age without diabetes and a 10-year risk of 5% to 7.5%, we recommend moderate statin therapy as an option after consideration of risk reduction, adverse events, drug interactions, and individual preferences to achieve either a low-density lipoprotein-cholesterol goal <130 mg/dl (<3.4 mmol/L) or a low-density lipoprotein-cholesterol reduction of 30-50%. (1|⊕⊕⊕⚪)
- 3.4.3 In individuals with metabolic risk, without diabetes, on statin therapy, we suggest monitoring glycemia at least annually to detect new-onset diabetes mellitus. (2|⊕⊕⊕⚪)
- 3.4.4 In individuals aged >75 years without diabetes and a 10-year risk ≥7.5%, we recommend discussing the benefits of statin therapy with the patient based on expected benefits versus possible risks/side effects. (1|⊕⊕⊕⚪)
Technical Remarks:
- Decisions should be made on a case-by-case basis depending on estimates of likely benefits vs. risks in individual patients.
- Statin therapy should be calibrated to reach the recommended low-density lipoprotein targets.
- 3.5 In individuals at metabolic risk who are taking statins with adequate low-density lipoprotein-cholesterol reduction, elevated triglyceride levels [≥200 mg/dl (2.3 mmol/L)], and reduced high-density lipoprotein levels [≤50 mg/dl (1.3 mmol/L) in females, or ≤40 mg/dl (1.0 mmol/L) in males], we suggest considering fenofibrate adjunct therapy. (2|⊕⊕⊕⚪)
Technical Remark:
- Avoid gemfibrozil in this situation.
- 3.6 In individuals aged 40 years and older at metabolic risk with low-density lipoprotein-cholesterol at target, an estimated 10-year atherosclerotic cardiovascular disease risk of >7.5% and without clinical atherosclerotic cardiovascular disease or other atherosclerotic cardiovascular disease risk factors, we suggest treatment with a moderate-intensity statin. (2|⊕⊕⊕⚪)
Blood Pressure Reduction
- 3.7 In individuals with blood pressure above 130/80 mmHg and a ten-year cardiovascular risk <10%, we suggest lifestyle management to lower blood pressure to <130/80 mmHg and to reduce the risk for atherosclerotic cardiovascular disease. (2|⊕⊕⊕⚪)
Technical Remarks:
- Since the 10-year risk is ≤10%, lifestyle intervention is appropriate and preferable to use of medications.
- Interventions include weight loss, healthy diet, sodium restriction, enhanced potassium intake, increased physical activity, and moderation of alcohol use.
- 3.8 In individuals without a history of atherosclerotic cardiovascular disease with metabolic risk who have a 10-year cardiovascular risk of <10% and blood pressure of <130/80 mmHg, we suggest the use of blood pressure-lowering medication in addition to lifestyle modifications for primary prevention of atherosclerotic cardiovascular disease only if lifestyle modification alone has failed. (2|⊕⊕⊕⚪)
Reducing Progression to Type 2 Diabetes
- 3.9 In individuals with prediabetes, we recommend prescribing lifestyle modification before drug therapy to reduce plasma glucose levels. (1|⊕⊕⊕⊕)
- 3.10 In individuals with prediabetes who have limitations to physical activity or are not responding to lifestyle modifications, we recommend metformin as a first pharmacologic approach to reduce plasma glucose levels. (1|⊕⊕⊕⚪)