Approach to Hypertension

Differential diagnosis

• Endocrine
  • Adrenal
    • Phaeochromocytoma
    • Conn’s syndrome
  • Cushing’s syndrome
    • Cushing’s disease: ACTH-producing pituitary adenoma
  • Acromegaly
  • Hyperthyroidism
• Renal
  • Renal artery stenosis
  • Autosomal-dominant polycystic kidney disease
  • Chronic glomerulonephritis
  • Diabetic nephropathy
• Obstructive sleep apnoea
• Inflammatory
  • Systemic sclerosis
  • Systemic lupus erythematosus
  • Wegner’s granulomatosis
• Drug-induced
  • Non-steroidal anti-inflammatory drugs
  • Erythropoietin
  • Cyclosporine / tacrolimus
  • Exogenous steroids
  • Oral contraceptive pill
  • Β-agonists
  • Liquorice
  • Excessive alcohol intake
  • Traditional Chinese medicines
• Metabolic
  • Obesity
  • Diabetes mellitus
  • Old age
  • Excessive salt intake
• Neoplastic
  • Intracranial tumours
• Congenital
  • Coarctation of the aorta
• Pregnancy

Relevant points in the history

• Hypertension
  • How long have you had high blood pressure for?
  • Does anyone in the family have high blood pressure?
  • Has the control been getting worse?
  • Do you have any headaches?
  • Have you noticed any blurred vision?
  • Have you ever felt like you are about to faint?
  • Do you have any chest pain?
  • Have you ever noticed any blood in your urine?
• Endocrine
  • Phaeochromocytoma
    • Do you ever notice your heart beating very quickly?
    • Do you have any unusual episodes of sweating?
    • Do you have any headaches which come on suddenly?
  • Cushing’s syndrome
    • Have you gained any weight?
    • Do you find that you bruise easily if you knock into things?
    • Do you have any difficulty getting up from a sitting position?
    • Do you have any stretch marks?
    • Have you ever fractured a bone from a fall?
  • Acromegaly
    • Has your appearance changed?
    • Do you feel like your shoe size has increased?
  • Hyperthyroidism
    • Are you unusually intolerant of the hot or the cold?
    • Have you noticed a tremor?
    • Have you noticed any double vision?
    • Are your periods unusually heavy?
    • Do you have any diarrhoea?
• Obstructive sleep apnoea
  • Do you feel very sleepy in the day?
  • Have you ever fallen asleep while driving?
  • Do you snore loudly at night?
• Renal parenchymal disease
  • Have you ever been tested for kidney disease?
  • Have you ever noticed any bubbles in your urine?
  • Are you passing a normal amount of urine for yourself?
• Intracranial tumour
  • Have you been troubled by a headache which is worse in the morning?
  • Do you have any weakness?
  • Do you have any tingling on one side of the body?
• Drug history
  • What medication do you take for your blood pressure?
  • Do you take all your medication as prescribed?
  • Have the doses of any of these changed recently?
  • Do you take any over the counter medicines?
  • Do you take any traditional or over-the-counter medicines?
  • Do you use the oral contraceptive pill?

Examination

• General
  • Appearance: acromegalic, Cushingoid
  • Graves’ ophthalmopathy
  • Pallor (chronic renal disease)
  • Obesity (OSA, difficult to control hypertension)
• Cardiovascular
  • Displaced apex beat (malignant hypertension)
  • Ejection systolic murmur (coarctation of the aorta)
    • Radio-femoral delay
  • Carotid bruits
  • Renal artery bruits (renovascular disease)
  • Femoral pulses (may be diminished in coarctation of the aorta)
  • Signs of cardiac failure (hypertensive end-organ damage, hyperthyroidism, acromegaly)
• Thyroid status
  • Pulse
  • Lid lag
  • Goitre
  • Pre-tibial myxoedema
  • Tremor
• Cushing’s
  • Abdominal striae
  • Proximal myopathy
  • Cataracts
  • Interscapular fat deposition
• Acromegaly
  • Prognathism
  • Prominent maxilla
  • Spade-like hands
• Offer fundoscopy to look for hypertensive retinopathy

Investigations

• Renal function to look for chronic kidney disease, potassium to look for hypokalaemia (endocrine causes)
• Morning serum renin : aldosterone ratio (high in Conn’s syndrome)
• Cushing’s syndrome
  • Overnight dexamethasone suppression test
  • 24 hour urine cortisol collection
• Phaeochromocytoma
  • 24 hour urine metanephrines
  • Plasma metanephrines
• Consider Doppler or magnetic resonance angiography of renal arteries to look for RAS
• Consider CT brain to look for intracranial tumour

Management

• Multidisciplinary team approach
• Patient education: weight reduction, reduction in dietary salt intake, increase in physical activity, moderate alcohol intake, compliance to medication
• Blood pressure targets (Joint National Committee 8, 2014)
  • Age < 60, diabetes or CKD – keep BP < 140/90
  • Age ≥ 60 – keep BP < 150/90
• Pharmacological management
  • Step 1
    • Age < 55, or patients with CKD – start with ACE inhibitor / angiotensin receptor blocker
    • Age ≥ 55, or Afro-Caribbean of any age – start with calcium channel blocker
  • Step 2: ACE inhibitor + calcium channel blocker
  • Step 3: ACE inhibitor + calcium channel blocker + thiazide-like diuretic
  • Step 4: consider adding β-blocker (may add earlier if the patient has ischaemic heart disease)
• Secondary hypertension
  • Phaeochromocytoma: α blockade (phenoxybenzamine) → β blockade, then definitive surgery
  • Cushing’s syndrome: stop offending medication, surgical tumour resection
    • Medical management: ketoconazole or etomidate if tumour not amenable to resection
  • Conn’s syndrome: spironolactone/eplerenone, definitive surgery
  • Hyperthyroidism: carbimazole, consider radioactive iodine, thyroidectomy
  • OSA: nocturnal continuous positive airways pressure
  • Renal artery stenosis: consider stenting for refractory patients / recurrent flash pulmonary oedema
    • RCTs: no difference in cardiovascular mortality between angioplasty and medical therapy