What Are the Causes of Sudden Hypertension in an Elderly Diabetic?

Hypertension, or high blood pressure, is a common medical condition that is associated with a high rate of morbidity. Hypertension can develop gradually or be sudden in onset. When high blood pressure occurs suddenly in an elderly person who has diabetes, it can be dangerous.

Background Physiology

• Blood pressure control, even in a healthy individual, is a complicated process, because it involves a combination of cardiac output and peripheral vascular resistance (PVR), each of which can be influenced by a variety of factors.

Abnormal Physiology

• In the elderly person, an abnormal increase in blood pressure can be caused by an increase in blood volume; electrolyte disturbances; kidney problems; pheochromocytoma (a tumor of the adrenal gland which secretes the hormone epinephrine); Cushing's disease (a tumor of the pituitary gland); and blood vessel disease. Often, disease of the blood vessels is a complication of diabetes mellitus.

Risk Factors

• Risk factors that contribute to the development of hypertension as a person ages are: smoking; obesity; high salt consumption in the diet; low potassium, calcium and magnesium in the diet; and high alcohol intake. Furthermore, because hypertension damages blood vessels, diabetes mellitus increases the chances of the development of hypertension. This in turn puts the individual at risk for a sudden rise in blood pressure.

Role of Diabetes in Hypertension

• Diabetes mellitus is one of the major risk factors for the development of atherosclerosis, a condition in which the artery walls thicken, thus interfering with blood flow. When this happens in the renal arteries (the arteries that supply the kidneys and adrenal glands), it causes a narrowing in the blood vessels, known as renal stenosis. The resulting decrease in circulation can be sudden, and when this happens, the system of hormones that regulates blood pressure (known as the renin-angiotensin system) is fooled, in a sense, into "thinking" that the blood pressure is too low. Thus, hormones are released from the adrenal glands and kidneys, which raise the blood pressure. This causes a type of viscous cycle known as a positive feedback mechanism, resulting in the blood pressure continuing to increase until life-threatening levels are reached.

Treatment

• When an elderly diabetic suffers from sudden hypertension, the blood pressure must be lowered immediately through the administration of diuretic medications. Later, other blood pressure-lowering drugs can be given to maintain blood pressure at safe levels. At the same time, the diabetes must be treated through monitoring of sugar levels in blood and urine and through the administration of sugar-lowering oral medications and/or injected insulin. To treat both diabetes and hypertension, patients must also be encouraged to exercise, stop smoking (if they smoke), keep alcohol consumption low, and eat a healthy diet.