At what levels of HDL (High-Density Lipoprotein), LDL (Low-Density Lipoprotein), triglycerides, blood pressure, and physical activity is screening for prediabetes and type 2 diabetes indicated?

From the Guidelines

Screening for prediabetes and type 2 diabetes is indicated for individuals with an HDL level less than 35 mg/dL, LDL greater than 130 mg/dL is not a specific indicator but those with high risk should be screened, triglycerides greater than 250 mg/dL, blood pressure of 140/90 mmHg or higher, or physical inactivity, as these factors are associated with an increased risk of developing insulin resistance and diabetes. According to the American Diabetes Association guidelines, as outlined in the 2018 standards of medical care in diabetes 1, testing for prediabetes and type 2 diabetes should be considered in overweight or obese adults who have one or more of the following risk factors:

• First-degree relative with diabetes
• High-risk race/ethnicity
• History of cardiovascular disease (CVD)
• Hypertension (≥140/90 mmHg or on therapy for hypertension)
• HDL cholesterol level <35 mg/dL and/or a triglyceride level >250 mg/dL
• Women with polycystic ovary syndrome
• Physical inactivity
• Other clinical conditions associated with insulin resistance The most recent guidelines from 2023 1 recommend screening for prediabetes and type 2 diabetes with an informal assessment of risk factors or validated risk calculator in asymptomatic adults, with testing beginning at age 35 years. Some key points to consider:
• Dyslipidemia, characterized by low HDL cholesterol and high triglycerides, is a significant risk factor for developing insulin resistance and type 2 diabetes.
• Hypertension, defined as a blood pressure of 140/90 mmHg or higher, is also a major risk factor for diabetes.
• Physical inactivity is another important risk factor, and individuals who engage in less than 150 minutes of moderate-intensity activity per week should be screened.
• Early detection and intervention can help prevent or delay the progression to diabetes and its complications. It's worth noting that while the provided evidence includes various studies and guidelines, the most recent and highest-quality study, which is the 2023 standards of medical care in diabetes 1, should be prioritized when making recommendations. Additionally, other evidence such as the 2014 standards of medical care in diabetes 1 and the primary prevention of ischemic stroke guideline 1 provide further insights into the risk factors and screening recommendations for prediabetes and type 2 diabetes. However, the 2023 guidelines 1 take precedence due to their recency and relevance to current clinical practice.

From the Research

Screening Indications for Prediabetes and Type 2 Diabetes

According to the American Diabetes Association guidelines, screening for prediabetes and type 2 diabetes is indicated in adults with certain risk factors. The provided evidence does not specify exact levels of HDL, LDL, triglycerides, blood pressure, and physical activity for screening indications. However, some studies suggest associations between lipid profiles and the risk of prediabetes and type 2 diabetes:

• A study published in 2022 found that elevated non-traditional lipid parameters, including the triglyceride-to-high-density lipoprotein cholesterol ratio (TG/HDL-C), were significantly associated with prediabetes and type 2 diabetes in patients with coronary heart disease 2.
• Another study published in 2014 found that subjects with HbA1c-defined prediabetes and type 2 diabetes had abnormalities in lipid profiles, including lower HDL cholesterol levels and higher triglycerides levels, compared to controls 3.

Risk Factors for Prediabetes and Type 2 Diabetes

The US Preventive Services Task Force recommends screening for prediabetes and type 2 diabetes in adults aged 35 to 70 years who have overweight or obesity 4. Other risk factors for prediabetes and type 2 diabetes include:

• Age: 45 years or older 5
• Family history of diabetes
• Physical inactivity
• Certain ethnicities
• History of gestational diabetes or delivering a baby weighing over 4 kg

Diagnosis of Prediabetes and Type 2 Diabetes

The diagnosis of prediabetes and type 2 diabetes can be made using various tests, including:

• Fasting plasma glucose test
• Oral glucose tolerance test
• Hemoglobin A1c (HbA1c) test
• Random plasma glucose test 5, 6