Secondary causes

It is thought that between 5-10% of patients diagnosed with hypertension have

primary hyperaldosteronism

, including Conn's syndrome. This makes it the single most common cause of secondary hypertension.

Renal disease accounts for a large percentage of the other cases of secondary hypertension. Conditions which may increase the blood pressure include:

• glomerulonephritis
• pyelonephritis
• adult polycystic kidney disease
• renal artery stenosis

Endocrine disorders (other than primary hyperaldosteronism) may also result in increased blood pressure:

• phaeochromocytoma
• Cushing's syndrome
• Liddle's syndrome
• congenital adrenal hyperplasia (11-beta hydroxylase deficiency)
• acromegaly

Drug causes:

• steroids
• monoamine oxidase inhibitors
• the combined oral contraceptive pill
• NSAIDs