Endocrine hypertension

Hypertension is an extremely common disorder, affecting 15% to 20% of the population.  More than 95% is of unknown etiology, termed primary or essential hypertension.

Patients who develop hypertension before the age of 30 who have a strong family history of hypertension, adrenal tumors, or develop a low potassium level (hypokalemia) should be screened for endocrine hypertension.

Various endocrine disorders may lead to the development of mild or severe hypertension and the elevation of blood pressure can be either permanent or only transient.

There are several causes of endocrine hypertension with the most common forms being renal artery stenosis, primary aldosteronism, and pheochromocytoma.

Pheochromocytoma are tumors from the chromaffin cells located in the adrenal medulla that produce catecholamines.

Pheochromocytoma can be detected with high sensitivity and specificity using urine and plasma catecholamine measurements.
Endocrine hypertension

Causes of secondary hypertension

Hypertension can be primary or secondary to a defined process. Secondary hypertension meaning the hypertension is secondary to a specific cause.

Secondary causes of hypertension are uncommon, and account for less than 5% of all cases of high blood pressure in and unselected hypertension population.

The rate of secondary forms of hypertension ranges between 4 and 8% in different patient populations (primary care, secondary care clinics, or specialized cardiovascular centers).

Secondary hypertension is usually associated with a specific organ and /or vascular abnormalities, a metabolic abnormality, or endocrine disorder.

The majority of secondary hypertension cases are due to chronic renal disease, and therapy often in includes antihypertensive medications.

Secondary hypertension must always be identified because treatment will be based on the specific underlying disorder. Its onset is often sudden, it may be more severe, a family history is frequently absent and it may occur in patients of all ages.

If left undiagnosed, secondary hypertension may lead to progressive target organ damage, as well as cardiovascular and renal complications.

Treatment usually differs from that of ordinary essential hypertension and with the right treatment, the amount of medication often can be reduced.
Secondary hypertension

Secondary hypertension

The majority of secondary hypertension cases are due to chronic renal disease and therapy often in includes antihypertensive medications. Secondary hypertension is uncommon. Over 95% of hypertensive patients have primary hypertension.

Only 1-2% of secondary hypertension cases can be cured by treatment of the underlying disease.

Causes of secondary hypertension includes: renovascular hypertension, pheochromocytoma, hyperthyroidism, Cushing’s syndrome, coartation of the aorta, and medications.

In addition, secondary hypertension can develop in association with comorbid conditions such as sleep apnea, panic disorders and/or depression.

Although infrequent, secondary of hypertension account for many cases of drug-resistance hypertension.

In secondary hypertension, the elevated blood pressure may be the major presenting manifestation of an underlying process, elevated blood pressure may simply be one component of a complex group of signs and symptoms in a patients with a systemic disease.

For some of the causes of secondary hypertension, simple interventions such as correction of renal arterial disease or removal of an offending medication can be curative.
Secondary hypertension

Etiology of Hypertension

Etiology of Hypertension
Hypertension observed in clinical practice is usually essential. That is, the hypertension is probably of genetic origin. Most data indicate that subtle disturbance in sodium handling by the kidney lead to increases in arterial pressure.

Approximately 10% of hypertension of secondary in nature, which can be attributed to either a kidneys or an endocrine cause. The most common secondary causes are renal parenchymal or vascular disease. Subtle degrees of kidney dysfunction are almost always associated with blood pressure elevation. Likewise renal artery disease can also occur at any age and can be associated with increased blood pressure.

Endocrine causes of hypertension are approximately 1% of the total and include diseases of the thyroid, parathyroid, or adrenal glands.

Clinical clues suggesting a secondary cause of hypertension include early onset hypertension (before age 30), sudden development of hypertension, or sudden loss of blood pressure control in patients whose blood pressure was previously well controlled.

Typically, most patients have essential hypertension and commonly have a parent or first degree relative with history of hypertension. The patient evaluation process helps discriminate between essential hypertension and secondary hypertension.

Evaluation should assess lifestyle and identify additional cardiovascular risk factors and concomitant disorders that could affect prognosis and treatment of hypertension.

One should identify possible secondary causes of hypertension such as chronic kidney disease, endocrinopathies, sleep apnea syndrome, or drug related hypertension and assess for the presence or absence of target organ damage.

Physical examination and thorough medical history are of the utmost importance. Routine laboratory tests and other diagnostic procedures may also be indicated.

Routine laboratory testing, including a comprehensive chemistry panel, complete blood count, and urinalysis, will provide important clues about estimated glomerular filtration rate and the presence or absence of abnormalities in the urinalysis such as red cells, white cells, or proteinuria, which could suggest kidney disease.

An ECG could give clues as to left ventricular hypertrophy. A lipoprotein profile can elucidate cardiovascular risks.
Etiology of Hypertension