MKSAP quiz: Diabetes screening

This month's quiz asks readers to evaluate a 40-year-old man who is healthy and asymptomatic but has some risk factors for diabetes.

A 40-year-old man is evaluated during a routine examination. He is healthy and asymptomatic, although he leads a sedentary lifestyle. Family history is noncontributory. He takes no medications.

On physical examination, temperature is normal, blood pressure is 120/74 mm Hg, pulse rate is 68/min, and respiration rate is normal. BMI is 32. The remainder of the physical examination is unremarkable.

When should this patient be screened for diabetes mellitus?

A. At age 45 years
B. At this visit
C. If he develops an additional risk factor for diabetes
D. No screening is indicated

MKSAP Answer and Critique

The correct answer is B. At this visit. This item is available to MKSAP 18 subscribers as item 149 in the General Internal Medicine section. More information about MKSAP 18 is available online.

Screening for diabetes mellitus should occur at this visit. The U.S. Preventive Services Task Force (USPSTF) recommends routine screening for abnormal blood glucose and diabetes in asymptomatic adults aged 40 to 70 years with overweight or obesity. Clinicians should offer or refer patients with an abnormal blood glucose level to intensive behavioral counseling interventions to promote a healthful diet and physical activity. In contrast to the USPSTF, the American Diabetes Association (ADA) recommends that screening be performed in patients of any age with overweight or obesity and one or more additional risk factors for diabetes. Risk factors include a first-degree relative with diabetes; high-risk race or ethnicity (African American, Latino, Native American, Asian American, Pacific Islander); history of cardiovascular disease; hypertension; HDL cholesterol level less than 35 mg/dL (0.91 mmol/L) and/or triglyceride level greater than 250 mg/dL (2.82 mmol/L); polycystic ovary syndrome; physical inactivity; and other conditions associated with insulin resistance (such as acanthosis nigricans and severe obesity). In patients with normal results, the ADA recommends repeat screening at 3-year intervals. This 40-year old patient with obesity meets the screening criteria of both the USPSTF and the ADA and should be screened for diabetes now.

In the absence of risk factors for diabetes, the ADA recommends that all patients be screened for diabetes at age 45 years. The USPSTF recommends screening only in asymptomatic adults aged 40 to 70 years with overweight or obesity. This patient, who has risk factors for diabetes (age 40 years, sedentary lifestyle, obesity), should be screened now, not at age 45 years or upon development of an additional diabetes risk factor.

Key Point

  • Screening for diabetes mellitus is recommended for patients with overweight or obesity and other risk factors for diabetes.