What annual laboratory tests are recommended for a general adult population with no specific medical history?

Annual Laboratory Tests for General Adult Population

For healthy adults without specific medical conditions, annual laboratory testing should include diabetes screening starting at age 35 (or earlier if overweight/obese with risk factors), lipid profile assessment, and blood pressure measurement, with additional age-appropriate cancer screenings beginning at age 45.

Core Metabolic Screening

Diabetes Screening

• All adults aged 35 and older should undergo diabetes screening regardless of risk factors using fasting plasma glucose, 2-hour plasma glucose during 75-g oral glucose tolerance test, or A1C 1
• Adults under 35 with BMI ≥25 kg/m² (or ≥23 kg/m² for Asian Americans) who have additional risk factors require earlier screening 2, 1
• Additional risk factors include: first-degree relative with diabetes, high-risk ethnicity, history of gestational diabetes, hypertension (≥140/90 mmHg), HDL <35 mg/dL, triglycerides >250 mg/dL, polycystic ovary syndrome, physical inactivity, or history of cardiovascular disease 3, 2
• If results are normal, repeat testing every 3 years minimum 3, 2
• Individuals with prediabetes (A1C 5.7-6.4%, impaired fasting glucose, or impaired glucose tolerance) require annual testing 3, 2

Lipid Profile

• Lipid panel testing (total cholesterol, HDL, LDL, triglycerides) should be performed with repeat assessments every 2 years for low-risk values and annually for high-risk values 2
• Non-fasting samples are acceptable for initial screening in average-risk individuals 4

Blood Pressure

• Blood pressure measurement should occur at every clinical visit 1, 4
• Annual screening is recommended for all adults, with more frequent monitoring for those at increased risk (African American, high-normal blood pressure, obesity, age >40 years) 1

Age-Specific Cancer Screenings

Starting at Age 45

• Colorectal cancer screening begins at age 45 with options including: annual fecal immunochemical test (FIT), multitarget stool DNA test every 3 years, colonoscopy every 10 years, CT colonography every 5 years, or flexible sigmoidoscopy every 5 years 2, 4
• Women should begin annual mammography at age 45 (with option to start between ages 40-44) 2
• Cervical cancer screening every 3 years with Pap test alone, or every 5 years with HPV test plus Pap test for women aged 30-65 2

Younger Adults (Ages 20-39)

• Cancer-related checkup every 3 years including examination for thyroid, testicular (males), lymph nodes, oral cavity, and skin cancers 4
• Testicular self-examination should be part of routine care for men 4

Age 50 and Beyond

• Prostate cancer screening discussions using shared decision-making about PSA testing for average-risk men 4

Baseline Laboratory Assessment

While not universally required annually for all healthy adults, the following may be considered based on clinical context:

• Complete blood count (CBC) provides valuable information about anemia, infection, and blood disorders, though it is not typically part of routine annual screening for asymptomatic healthy adults 5, 6, 7
• Comprehensive metabolic panel assesses kidney function, liver function, and electrolyte balance when clinically indicated 4
• Urinalysis with albumin-to-creatinine ratio for kidney disease screening in at-risk populations 4

Critical Pitfalls to Avoid

Ethnicity-Specific Considerations

• Use BMI threshold of ≥23 kg/m² for Asian Americans (versus ≥25 kg/m² for other populations) when determining diabetes screening eligibility 2

Test Limitations

• A1C may be unreliable in conditions affecting red blood cell turnover including pregnancy (second and third trimesters), recent blood loss or transfusion, hemoglobinopathies (such as sickle cell trait), erythropoietin therapy, or hemolysis 3, 2
• In these situations, use only blood glucose criteria (fasting plasma glucose or oral glucose tolerance test) for diabetes diagnosis 3

Follow-Up Requirements

• All positive screening tests require appropriate diagnostic follow-up - particularly for colorectal cancer screening where positive non-colonoscopy tests must be followed with timely colonoscopy 2
• Abnormal results near diagnostic thresholds should be repeated in 3-6 months to confirm diagnosis 3

Risk-Based Intensification

• Women with history of gestational diabetes require lifelong testing at least every 3 years 2
• Individuals meeting criteria for prediabetes need annual (not every 3 years) diabetes screening 3, 2
• More frequent testing intervals should be considered based on initial results and evolving risk status 3