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What is hypertension?


Hypertension and Blood Pressure

Blood pressure normally fluctuates throughout the day -- for example blood pressure is lowest at night while you're asleep and gradually climbs throughout the day, peaking in the mid-afternoon. Abnormal fluctuations such as high blood pressure readings at night could be caused by lifestyle factors such as too much stress, too much caffeine or too much tobacco but those fluctuations could also be indicators of uncontrolled high blood pressure, kidney disease, sleep apnea or adrenal gland tumors. Over time, consistently high blood pressure can contribute to atherosclerosis (hardening of the arteries) and heart failure.

Several factors contribute to the risk for developing hypertension. Some we can influence with lifestyle changes, some we cannot:

  • Smoking
  • Obesity
  • A diet high in fat and salt
  • Inactivity
  • Stress
  • Older age
  • Family history and genetics
  • Race and ethnicity
  • Gender
  • Disease or medical conditions, including chronic kidney disease, adrenal and thyroid disorders, sometimes even in pregnancy, may also cause high blood pressure. This is known as secondary hypertension.

While you can't change your genetics, you can work with what you've got. In a scientific statement published by the American Heart Association, successfully treating hypertension means it first needs to be diagnosed, which can be difficult due to its asymptomatic nature, and then healthy diet and exercise changes and drug treatment should begin -- usually a lifelong lifestyle and drug plan. Drugs to control blood pressure come in different flavors. One type, diuretics, removes extra water and salt from the body). Others, such as beta blockers, ACE inhibitors and nervous system inhibitors, work to relax and widen blood vessels.

Studies show that when you lower your blood pressure you lower your associated risk of myocardial infarction (heart attack) by 20 to 25 percent and your risk of stroke by 35 to 40 percent, according to a report published in the July 2008 issue of Journal of the American Society of Hypertension.

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