Resistant hypertension is common in clinic, but true resistance is less common than it first appears. A systematic approach finds the cause in many patients.
Confirm it is truly resistant
Resistant hypertension means blood pressure above target despite three drugs, including a diuretic, at optimal doses. Before labelling a patient, exclude pseudo-resistance:
- Incorrect measurement technique or cuff size
- Poor adherence to medicines
- White-coat effect, ideally excluded with home or ambulatory monitoring
Look for secondary causes
Primary aldosteronism is the most common secondary cause and is under-diagnosed. Screen with the aldosterone-to-renin ratio. Also consider sleep apnoea, chronic kidney disease, renal artery stenosis and interfering drugs such as NSAIDs.
The fourth drug
In the PATHWAY-2 trial, spironolactone was the most effective add-on drug for resistant hypertension. Monitor potassium and kidney function after starting it.
Treatment targets: the 2024 ESC guidelines recommend a systolic target of 120 to 129 mmHg for most adults, if tolerated.
When to refer
Refer patients with suspected secondary hypertension, those who remain uncontrolled on four drugs, and those who may benefit from renal denervation at an experienced centre.
References
- McEvoy JW, et al. 2024 ESC Guidelines for the management of elevated blood pressure and hypertension. Eur Heart J. 2024;45:3912-4018.
- Williams B, et al. Spironolactone versus placebo, bisoprolol, and doxazosin to determine the optimal treatment for drug-resistant hypertension (PATHWAY-2). Lancet. 2015;386:2059-2068.
Educational content for healthcare professionals. Always refer to the full guideline and use clinical judgement. Medical disclaimer
Written by Dr. Vikram Shah Interventional Cardiologist, Mumbai View profile
