The vast majority of hypertension, or high blood pressure, is termed essential. It has no single, reversible cause, notes MayoClinic.com. Conversely, secondary hypertension stems from a separate, treatable medical problem. The first test for hypertension must accurately make the diagnosis. A battery of tests may then be performed to evaluate damage the blood pressure may have caused and identify other health risks. Testing for secondary hypertension is performed when it is suspected, such as in younger people with high blood pressure.
Diagnosis
A quality assessment of blood pressure is important when making a diagnosis of hypertension. The cuff must fit well and be properly calibrated. The Seventh Report of the Joint National Committee on Prevention, Detection, Evaluation and Treatment of High Blood Pressure recommends that the patient be seated for at least five minutes before the test is performed, and two readings should be obtained. Often, blood pressure measurement will be followed over time to identify the trend.
Organ Damage
Elevated blood pressure may damage the heart, kidneys or eyes. An electrocardiogram may be done to evaluate the electrical activity of the heart. This may reveal an enlarged heart or a previous heart attack. An analysis of urine is done looking for clues about kidney abnormalities. Blood tests for blood urea nitrogen and creatinine also reflect kidney health, as do the measurement of potassium, sodium and calcium. An eye care professional may be consulted to evaluate the condition of the retinas.
Cardiovascular Risks
Hypertension is well known to increase the risk of heart attack and stroke. This risk is increased if other factors are also present. A fasting blood sugar test may be done to screen for diabetes. Measurement of the cholesterol panel can identify those people with lipid abnormalities.
Secondary Hypertension
Numerous disorders may lead to hypertension, as discussed in "American Family Physician". A thorough investigation should be undertaken when a secondary cause is suspected. A sleep study may identify patients with obstructive sleep apnea. The hormone aldosterone regulates sodium and water balance in the body, and abnormalities in this system may be detected through blood tests. Abnormalities in growth hormone or the thyroid or parathyroid systems can also be detected through blood work. Kidney problems may lead to high blood pressure. The kidneys may be evaluated through ultrasound, studies of the urine and blood and specialized radiography examinations. A narrowing of the aorta can be seen on CT scan. Cushing's disease is associated with hypertension, weight gain, fatigue and skin abnormalities. It may be diagnosed through a blood test. Pheochromocytoma is a rare tumor that produces excess amounts of adrenaline. It may be discovered by testing for the presence of chemicals passed through the urine.
