What laboratory tests are indicated for a patient presenting with hypertension (high blood pressure)?

From the Guidelines

For a patient with high blood pressure, I recommend ordering a comprehensive set of laboratory tests including fasting blood glucose, complete blood count, lipid profile, serum creatinine with eGFR, serum sodium, potassium, calcium, thyroid-stimulating hormone, urinalysis, and an electrocardiogram. These tests are essential for evaluating the patient's cardiovascular risk factors, assessing target organ damage, and screening for secondary causes of hypertension, as recommended by the 2017 ACC/AHA/AAPA/ABC/ACPM/AGS/APhA/ASH/ASPC/NMA/PCNA guideline for the prevention, detection, evaluation, and management of high blood pressure in adults 1. The guideline suggests that these basic laboratory tests should be obtained for all patients with a new diagnosis of hypertension to facilitate CVD risk factor profiling and establish a baseline for medication use.

• Key laboratory tests include:
  • Fasting blood glucose to assess for diabetes, a common comorbidity with hypertension
  • Complete blood count to screen for anemia or infection
  • Lipid profile to evaluate cardiovascular risk factors
  • Serum creatinine with eGFR to assess kidney function
  • Serum sodium, potassium, and calcium to evaluate electrolyte balance
  • Thyroid-stimulating hormone to screen for thyroid dysfunction
  • Urinalysis to detect protein or blood in the urine, indicating kidney damage
  • Electrocardiogram to assess for cardiac effects of hypertension Optional tests, such as echocardiogram, uric acid, and urinary albumin to creatinine ratio, may be considered to provide additional information on target organ damage, but are not universally recommended for all patients with hypertension 1.

From the Research

Laboratory Tests for Hypertension

To evaluate a patient with high blood pressure, the following laboratory tests are recommended:

• Accurate blood pressure measurement
• Focused history and physical examination
• Basic tests, such as:
  • Electrolyte panel
  • Renal function tests
  • Lipid profile
  • Urinalysis
  • Electrocardiogram (ECG) 2

Rationale for Test Selection

The selection of laboratory tests is based on the need to:

• Confirm the diagnosis of hypertension
• Identify potential secondary causes of hypertension
• Assess cardiovascular risk factors
• Evaluate for target organ damage 2

Treatment Implications

The choice of laboratory tests may also have implications for treatment, such as:

• Selection of antihypertensive medication, including calcium channel blockers, ACE inhibitors, and diuretics 3, 4
• Monitoring of treatment efficacy and potential side effects
• Adjustment of treatment regimen as needed to achieve blood pressure goals and minimize cardiovascular risk 3, 4