What is the recommended work-up for suspected secondary hypertension?

From the Guidelines

The recommended work-up for suspected secondary hypertension should begin with a thorough clinical evaluation, including a detailed medical history and physical examination, followed by basic laboratory testing such as serum sodium, potassium, eGFR, TSH, and dipstick urine analysis, as suggested by the 2020 international society of hypertension global hypertension practice guidelines 1. The initial assessment should focus on identifying potential underlying causes of secondary hypertension, including medication use, family history of endocrine disorders, and symptoms suggesting specific conditions.

Key Components of the Work-up

• A detailed medical history focusing on medication use, including over-the-counter drugs, herbal supplements, and illicit substances
• Physical examination to assess for signs such as abdominal bruits, cushingoid features, or delayed femoral pulses
• Basic laboratory testing, including serum sodium, potassium, eGFR, TSH, and dipstick urine analysis
• Further investigations, such as additional biochemistry, imaging, or other tests, should be carefully chosen based on information from the history, physical examination, and basic clinical investigations, as recommended by the 2020 international society of hypertension global hypertension practice guidelines 1.

Importance of Targeted Testing

More targeted testing depends on clinical suspicion, and the 2024 ESC guidelines for the management of elevated blood pressure and hypertension suggest that patients with hypertension presenting with suggestive signs, symptoms, or medical history of secondary hypertension should be appropriately screened for secondary hypertension 1.

Coordination of Tests and Medication Adjustments

The timing of these tests should be coordinated with medication adjustments, as certain antihypertensives can affect test results, highlighting the importance of a systematic approach to identifying secondary causes of hypertension.

Specialist Referral

Consider referring patients with suspected secondary hypertension to a specialist center with access to appropriate expertise and resources, as recommended by the 2020 international society of hypertension global hypertension practice guidelines 1, to ensure comprehensive evaluation and management.

From the Research

Recommended Work-up for Suspected Secondary Hypertension

The work-up for suspected secondary hypertension involves a combination of clinical evaluation, laboratory tests, and specialist advice. The following steps are recommended:

• History taking and examination to look for clinical clues, such as early-onset, severe or resistant hypertension, suggestive family history, or clinical clues that point to a specific secondary cause 2
• Laboratory tests, including:
  • Electrolytes, urea, creatinine 2
  • Aldosterone:renin ratio, with consideration of potentially interfering antihypertensive drugs 2
  • Urinalysis and urine albumin:creatinine ratio 2
• Abnormal results should prompt further investigation, with specific testing available depending on the risk and cost of the workup and treatment 3
• 24 h ambulatory blood pressure (BP) monitoring may play a central role in the work up of patients with suspected secondary hypertension 4

Common Causes of Secondary Hypertension

The most common causes and associations of secondary hypertension include:

• Renal disease 2, 4
• Primary aldosteronism 2, 5
• Obstructive sleep apnoea 2, 4, 5
• Medicines, illicit substances, and alcohol 2
• Renovascular hypertension 5
• Drug-induced hypertension 5

Evaluation and Management

The evaluation and management of secondary hypertension involve:

• Identifying the underlying cause of hypertension 3, 5
• Targeted therapies to supplement first-line antihypertensive agents 5
• Specialist advice, if needed 2
• Early detection and treatment to minimize/prevent irreversible changes in the vasculature and target organs 4