Resistant Hypertension in Chronic Kidney Disease

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Secondary Causes of Resistant Hypertension and their

Pertinent Features

• Primary hyperaldosteronism—Hypokalaemia, fatigue, low renin levels despite
  drug treatment that would be expected to elevate rennin levels (i.e. ACE inhibitor
  or angiotensin receptor blocker plus a calcium channel blocker and diuretic) and
  usually raised aldosterone levels


• Renal artery stenosis—Carotid, abdominal or femoral bruits; history of flash pul-
  monary oedema; young females (fibromuscular dysplasia); history of atheroscle-
  rotic disease


• Renal parenchymal disease—Albuminuria/proteinuria, or microscopic haematu-
  ria, reduced eGFR or formally measured renal function, nocturia and oedema
  
  
  • Renal cystic disease—classically ADPKD
  
  
  
  


• Obstructive sleep apnoea—Obesity, short neck, daytime somnolence, snoring,
  frequent night-time awakenings and witnessed apnoea


• Phaeochromocytoma—Episodic palpitations, labile BP, headaches and
  sweating.


• Thyroid diseases—Eye signs, weight loss or gain, heat or cold intolerance, heart
  failure, tachycardia, bradycardia and anxiety or fatigue.


• Cushing’s syndrome—Centripetal obesity, moon facies, abdominal striae and
  interscapular fat deposition


• Coarctation of the aorta—Radio-radial or radio-femoral delay, diminished femo-
  ral pulses and rib notching on chest radiograph


• Intracranial tumours—Early morning headache and family history
  
  
  • Porphyria
    In patients with true resistant hypertension, thiazide diuretics, particularly
    chlorthalidone, should be considered as one of the initial agents. The other two
    agents should include calcium channel blockers and angiotensin-converting enzyme
    inhibitors for cardiovascular protection. An increasing body of evidence has sug-
    gested benefits of mineralocorticoid receptor antagonists, such as spironolactone
    (grade 2B) and eplerenone, in improving blood pressure control in patients with
    resistant hypertension, regardless of circulating aldosterone levels. Thus, this class
    of drugs should be considered for patients whose blood pressure remains elevated
    after treatment with a three-drug regimen to maximal or near-maximal doses.
    Resistant hypertension may be associated with secondary causes of hypertension
    including obstructive sleep apnoea or primary aldosteronism. Treating these disor-
    ders can significantly improve blood pressure beyond medical therapy alone (4–6).
    A number of new interventions and devices might help target truly refractory
    patients—these include renal sympathetic denervation, formation of a large proxi-
    mal arteriovenous fistula, carotid sinus baroreflex stimulation and several other
    options (7–9).
  
  
  
  

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