Secondary Hypertension

A blood pressure which is measured as 120/80 mmHg is said to be a normal reading. If the reading is above the normal levels, it is termed as high blood pressure. In majority of people, high blood pressure is caused by any other underlying diseases, such as kidney damage, damage to arteries or heart problems. This kind of blood pressure is called secondary hypertension. On the other hand, if the cause of hypertension is idiopathic (of unknown cause), then it is called as primary hypertension

The incidence of secondary hypertension is less when compared to primary hypertension.

Causes

Many causes contribute in the development of secondary hypertension which includes:

Kidney disease: Damage to the kidneys result in narrowing of renal arteries causing an increase in blood pressure.

Abnormalities of the adrenal gland: Adrenal glands secrete various hormones that regulate blood pressure. Adrenal diseases such as pheochromocytoma, hyperaldosteronism, and hypercortisolism can alter blood pressure.

Diabetes complications: In the case of diabetic nephropathy, damage to kidneys occur leading to secondary hypertension.

Hyperparathyroidism: Parathyroid hormone regulates calcium and phosphorous levels in the body. If the hormone levels in the body increase, calcium level also raises triggering high blood pressure.

Sleep apnea: In this condition, inhalation of oxygen decreases leading to damage of blood vessel linings. This damage ultimately causes a rise in blood pressure.

Obesity: The amount of blood circulation increases putting pressure on the arteries. This causes a rise in blood pressure leading to secondary hypertension.

Pregnancy: Women during pregnancy are also at risk of secondary hypertension.

Symptoms of secondary hypertension include:

  • Persistent rise in blood pressure (systolic blood pressure > 180 mmHg; diastolic blood pressure >120 mmHg) even after using medications
  • Sudden onset of high blood pressure before the age of 30 and after 55
  • No family history of hypertension

The complications of secondary hypertension are damage to the arteries, formation of an aneurysm, weakened blood vessels in eyes and kidneys, heart failure, and impairment of memory, and metabolic syndrome.

Your doctor initially measures your blood pressure for six to seven times at different visits. If the blood pressure is persistently high during all the measurements, your doctor may give the provisional diagnosis as secondary hypertension. Your doctor may also recommend following tests to confirm the diagnosis.

  • Blood test – to check levels of electrolytes (sodium, potassium, calcium, and chloride), creatinine, blood urea nitrogen (BUN), blood glucose, cholesterol
  • Urine test - to check for the markers of high blood pressure
  • Ultrasound of kidneys – to know whether the underlying cause is kidney damage
  • Electrocardiogram – to evaluate whether the underlying cause is a heart problem
  • Magnetic resonance angiography – in cases of renal stenosis

The primary goal of the treatment of secondary hypertension is to treat the underlying cause. After diagnosis, your doctor recommends appropriate treatment for the cause (may be adrenal gland abnormalities, kidney disease, diabetes, or sleep apnea). Your doctor also prescribes antihypertensive medications such as diuretics, beta blockers, angiotensin-converting enzyme (ACE) inhibitors, or calcium channel blockers.

If there is damage or narrowing of the arteries, your doctor may recommend surgery to correct the problem. If the secondary hypertension is drug-induced (caused by use of any medication), then your doctor suggests to stop taking the medication or decreasing the dose of the medication or tries to give any alternative medication.

To keep your blood pressure, adopt some measures:

  • Eat healthy foods.
  • Maintain a healthy weight.
  • Perform regular physical activity.
  • Reduce the intake of sodium in diet.
  • Stop smoking and alcohol consumption.
  • Take blood pressure medication as prescribed.