In the United States, about 1 in 3 adults has high blood pressure. About 25% of people with high blood pressure are unaware that they have it.
About 25% of American adults have prehypertension. People who are diagnosed with prehypertension (blood pressure ranges from 120 - 139/80 - 89 mm Hg) are at increased risk of developing high blood pressure.
Age and Gender
Age is the major risk factor of hypertension. Men over age 45 and women over age 55 are at increased risk for high blood pressure. Over half of Americans over age 60 have hypertension. Hypertension is also becoming more common in children and teenagers. Among younger people, boys are at higher risk for high blood pressure than girls.
Race and Ethnicity
Compared to Caucasians and other ethnic groups, African-Americans are much more likely to have high blood pressure. More than 40% of African-American men and women have hypertension. It may account for over 40% of all deaths in this group. High blood pressure tends to start at a younger age among African-Americans, is often more severe, and causes greater risks for premature death from heart attack, stroke, heart failure, and kidney failure.
People with parents or other close relatives who have high blood pressure have an increased risk of developing it themselves.
About a third of patients with high blood pressure are overweight. Even moderately obese adults have double the risk of hypertension than people with normal weights. Children and adolescents who are obese are at increased risk for high blood pressure when they reach adulthood.
Obstructive Sleep Apnea
Obstructive sleep apnea, a disorder in which breathing halts briefly but repeatedly during sleep, is present in many patients with hypertension. The relationship between sleep apnea and hypertension has been thought to be largely due to obesity, but studies are finding a higher rate of hypertension in people with sleep apnea regardless of their weight.
Smoking. Cigarette smoking is a major risk factor for high blood pressure.
Salt and Potassium. Eating too much salt (sodium) can increase the risk for developing high blood pressure. Similarly, a diet that is too low in potassium can make the body accumulate too much sodium. Sodium and potassium are important regulators of fluid balance in cells.
Alcohol. Chronic heavy alcohol use can increase blood pressure. Women may be more sensitive than men to the blood pressure effects of alcohol.
Physical Inactivity. A sedentary lifestyle and lack of physical activity can increase the risk of becoming overweight.
Stress. Mental and emotional stress can cause a temporary increase in blood pressure. Chronic stress can lead to engaging in unhealthy behaviors (overeating, smoking, alcohol use, lack of exercise) that contribute to high blood pressure.
Review Date: 04/06/2010
Reviewed By: Harvey Simon, MD, Associate Professor of Medicine, Harvard Medical School; Physician, Massachusetts General Hospital. Also reviewed by David Zieve, MD, MHA, Medical Director, A.D.A.M., Inc.