Complications:

Hypertension places stress on several organs (called target organs), including the kidneys, eyes, and heart, causing them to deteriorate over time. High blood pressure contributes to 75% of all strokes and heart attacks. It is particularly deadly in African-Americans.

Risk of complications or rapid progression of hypertension become more likely in the presence of other risk factors, including significant elevation of blood pressure, increasing age (men over age 55 and women over age 65), smokers, abnormal cholesterol, family history of premature heart disease, obesity, diabetes, coronary artery disease, and other evidence of vascular disease.

Hypertension is a disorder characterized by chronically high blood pressure. It must be monitored, treated and controlled by medication, lifestyle changes, or a combination of both.

Emergency Conditions

Malignant hypertension, an emergency condition resulting from untreated primary hypertension, can be lethal. Most patients have significant elevation of their blood pressure and symptoms of acute heart, cerebrovascular, or kidney involvement.

Stroke

About two-thirds of people who suffer a first stroke have moderate elevated blood pressure (160/95 mm Hg or above). Hypertensive people have up to 10 times the normal risk of stroke, depending on the severity of the blood pressure in the presence of other risk factors. Hypertension is also an important cause of so-called silent cerebral infarcts, or blockages, in the blood vessels in the brain (mini-strokes) that may predict major stroke or progress to dementia over time.

Alzheimer's Dementia

Isolated systolic hypertension may pose a particular risk for dementia different than the dementia associated with multiple small strokes. However to date, there is no clear evidence that the use of antihypertensive medications reduce the occurrence of Alzheimer's disease.

Heart Disease

High blood pressure is a major risk factor for heart disease.

Heart Attack. About half of people who suffer their first heart attack have moderate hypertension (160/95 mm Hg) or greater. High blood pressure increases the risk for a heart attack by up to five times, depending on the severity of the hypertension.

Heart Failure. Uncontrolled high blood pressure (hypertension) is a major cause of heart failure even in the absence of a heart attack. In fact, about 75% of cases of heart failure start with hypertension. It generally develops as follows:

• The heart muscles thicken to make up for increased blood pressure.
• The force of heart muscle contractions weaken over time, and the muscles have difficulty relaxing. This prevents the normal filling of the heart with blood.

Diabetes and Kidney Disease

Diabetes. High blood pressure, and some of the medications used to treat it, can increase the risk for developing diabetes.

End-Stage Kidney Disease. High blood pressure causes 30% of all cases of end-stage kidney disease (medically referred to as end-stage renal disease, or ESRD). Only diabetes leads to more cases of kidney failure. Patients with diabetes and hypertension need to be monitored very closely for the development of kidney disease.

Effect on the Eyes

High blood pressure can injure the blood vessels in the eyes, causing a condition called retinopathy.

Sexual Dysfunction

Sexual dysfunction is more common and more severe in men with hypertension and in smokers than it is in the general population. Many of the drugs that treat hypertension are thought to cause impotence as a side effect. In these cases, it is reversible when the drugs are stopped. More recent evidence suggests, however, that the disease process that causes hypertension is itself the major cause of erectile dysfunction in these men.

Newer anti-hypertensive drugs, including angiotensin-converting enzyme (ACE) inhibitors and angiotensin-receptor blockers (ARBs), are much less likely to cause erectile dysfunction. Oral phosphodiesterase type 5 (PDE5) inhibitors, such as sildenafil (Viagra), do not appear to pose a risk for men who have both high blood pressure and erectile dysfunction.

Pregnancy, Hypertension, and Preeclampsia

Many women likely to develop hypertension when they are older have their first elevated blood pressure readings during pregnancy. Elevated blood pressure readings generally show up early in pregnancy, before 16 - 20 weeks. (This condition is different than preeclampsia, described just below.) These women often require antihypertensive medications during pregnancy and closer monitoring of themselves and the fetus. Continued hypertension after the pregnancy is also not uncommon.

Severe, sudden high blood pressure in pregnant women is one component of a condition called preeclampsia (commonly called toxemia) that can be very serious for both mother and child. Preeclampsia occurs in up to 10% of all pregnancies, usually in the third trimester of a first pregnancy, and resolves immediately after delivery. Other symptoms and signs of preeclampsia include protein in the urine, severe headaches, and swollen ankles.

The risk for preeclampsia is higher for first births, multiple births, and for very young women (teenagers) and those over age 35. Pre-existing high blood pressure, diabetes, and kidney disease also increase the risk for preeclampsia. There appears to be a genetic component for this condition, so women whose mothers experienced preeclampsia are also at higher risk.

The reduced supply of blood to the placenta can cause low birth weight and eye or brain damage in the fetus. Severe cases of preeclampsia can cause kidney damage, convulsion, and coma in the mother and can be lethal to both mother and child. Evidence also suggests that preeclampsia can lead to increased risks later in life for coronary heart disease and other heart problems.

Women at risk for preeclampsia (particularly those with existing hypertension) are monitored carefully for its presence. Both mother and fetus are monitored closely after a diagnosis. Blood pressure medications may be required. Delivery is the main cure for preeclampsia. In severe cases, the obstetrician will need to induce pre-term birth.

Outlook for Children with Hypertension

Children with high blood pressure should first be treated with lifestyle changes, including weight reduction, increased physical activity, and diet modification. If blood pressure is not controlled with lifestyle changes, drug treatment may be required. Although there are few clinical trials conducted in children, a 2005 study found that the angiotensin receptor blocker losartan was safe and effective in children. Results of studies evaluating outcomes of children with hypertension suggest that early abnormalities, including enlarged heart and abnormalities in the kidney and eyes, may occur even in children with mild hypertension. Children and adolescents with hypertension should be monitored and evaluated for any early organ damage. Secondary hypertension (high blood pressure due to another disease or drug) is more common in children than adults.