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
