Hypertension

Incidence

Hypertension affects nearly 1/4 of American adults, or nearly 50 million people in this country alone. Unfortunately most don't even know they have it.  It is a the major risk factor contributing to most strokes, heart attacks, congestive heart failure and kidney failure.  Because it causes no symptoms until one of these complications develops, it is often called the "silent killer". For reasons that are not completely understood, it is more common in the black population, but occurs commonly in all races. Hypertension also becomes more common as you get older. 

Definition

Hypertension is defined as having a Systolic ( top number) blood pressure of 140 or greater, or a Diastolic ( bottom number) of 90 or greater.  The top number represents the pressure when the heart contracts and the lower number is the pressure exerted when the heart is in its relaxed state

Usually a doctor will take your blood pressure on several different occasions before making the diagnosis of hypertension. If three separate readings show numbers consistent with hypertension then the diagnosis is made.

Borderline Hypertension is a somewhat recently described category.  Although Hypertension is defined as a BP 140/90 or greater the risk of cardiovascular disease actually starts to climb even before that point. For this reason we have created a new category called Pre-hypertension or Borderline Hypertension. If someone has a systolic blood pressure of 130-139, or a diastolic blood pressure of 80-89 they are said to be borderline hypertensive. While such individuals do not meet the classic criteria for hypertension they are a greater risk of developing high blood pressure than the average individual and need to focus on limiting risk factors which they can control ( see below).

Risk Factors

The two risk factors that contribute the most to the risk of developing hypertension are genetics and age. These two factors probably contribute more to hypertension risk than all other known risk factors combined. Unfortunately there's not much that can be done about either of these. You can't pick your parents and you can't stop getting older. Age is such an overwhelming risk factor that 2/3 of people over the age of 60 will have hypertension, and the overall risk of developing hypertension sometime during a person's lifetime is 90%.

The good news is that there are some risk factors that we can control. The following is a list of risk factors which have been associated with hypertension.

Treatment

Treatment for hypertension usually focuses first on lifestyle changes. If the blood pressure is very high or if lifestyle changes alone can not bring the blood pressure in to the goal range then medications may be added.

Lifestyle changes

 Initial treatment should focus on modifying as many of these lifestyle factors as possible.  
  • Increase your exercise. Ideally this should included 2.5 hours per week or more of moderate aerobic exercise.
  • Reduce salt intake
  • Eat a healthy diet. The DASH diet is a heart and BP healthy diet.
  • Increase intake of High Potassium Foods - See list HERE

Hypertensive Medications

If lifestyle changes don't control your blood pressure, treatment often requires the use of medications. There are now more than a half dozen major classes of blood pressure medications available. Each class uses a different method to control your blood pressure. Because they work differently, combining more than one medication can be more effective. Usually two or three medications are required in order to get adequate control. An additional benefit to using several medications, is that it allows the doctor to use lower doses of each medication and thereby reduce the chance of side effects.
There are several different types or classes of blood pressure medications and within each class there are several different medications . Below are some of the more common classes of medications used by doctors to treat high blood pressure.

Diuretics
Pros 
  • Long safety history
  • Inexpenisve
  • Once a day
Cons
  • Slight increase in urinary frequency
  • Can affect potassium levels
  • May raise sugar, uric acid and creatinine levels
Examples
  • Hydrochlorothiazide
  • Chlorthalidone
ACEI's (Angiotensin Converting Enzyme Inhibitors)
Pros
  • Good safety profile
  • Once a day
  • Inexpensive
  • Provides additional kidney protection for diabetics
Cons
  • Can cause a dry cough in about 19% of patients
  • Small risk of angioedema
Examples
  • Lisinopril
  • Enalapril
  • Captopril
  • Quinapril
ARB's (Angiotensin Receptor Blockers)
Pros
  • Once a day
  • Very good safety profile
  • Can protect kidneys from diabetes injury like ACEI's
  • Like ACEI's but without the risk of cough
Cons
  • Sometimes more expensive than ACEI's
  • Small risk of Angioedema
Examples
  • Valsartan
  • Olmesartan
  • Candesartan
CCB's (Calcium Channel Blockers)
Pros
Cons
Examples
Beta Blockers
Pros
Cons
Examples
  • Atenolol (Tenormin)
  • Metoprolol (Lopressor, Toprol XL)
  • Propranolol (Inderal LA)
  • Bisoprolol (Zebeta)

This is not a complete list but it is a list of the classes of drugs that are used most frequently.

Blood Pressure Myths

"I would know if I had high blood pressure because I would feel it"
Actually high blood pressure usually causes no symptoms at all. When people talk about feeling stressed or having a headache when their pressure is up, its usually the stress or the pain from the headache that's causing the blood pressure to go higher not the other way around. High blood pressure rarely causes any symptoms until you have a stroke or heart attack.
" I heard that once you start blood pressure medication you will be stuck on it for the rest of your life"
While it is true that treating blood pressure is usually a life long process, you do not become "addicted to" or "dependant on" blood pressure medication. The medications we use to treat high blood pressure can only control the pressure, they can't cure it. If you come off the medication your pressure will go right back to where it would have been if you had never taken anything. Sometimes lifestyle changes like exercise, losing weight and quitting smoking will improve your pressure to the point where you won't need medication, but most people do require some sort of treatment for the rest of their lives.
" I only have high blood pressure when I'm in the doctor's office. It's always fine at home so I don't have to worry about it, right?"
This condition is often called "white coat syndrome". In the past most doctors assumed that this was a harmless condition brought on by the stress of coming to the doctor. Recent studies have shown however, that many people diagnosed with white coat syndrome have the same risk of stroke and heart attack as people who always have high blood pressure.

Patients frequently assume that if their blood pressure is normal at home and high at the doctor's office, they were "just nervous". While this is certainly true for some people, many other people are hypertensive most of the time and only have normal blood pressure when they are relaxed at home on the couch. To determine which of these two explanations apply in your case your doctor may recommend that you undergo an Ambulatory Blood Pressure Monitor (ABPM). This is a device that you will wear for 24 hours. During that time the machine will take your blood pressure at regular intervals without warning. Usually it will do this every 1/2 hour during the day and once an hour at night. The readings are recorded on a built in memory chip. When the 24 hour period is over you will return the monitor to your doctor who will download the readings to a computer. The computer will then generate a report that shows every reading that was taken. The readings are plotted on a graph and the doctor can then see what percent of your readings are normal, borderline, or hypertensive. In addition the report shows the doctor what happens to your blood pressure at different times of the day. Based on these readings your doctor can determine whether your "white coat syndrome" requires further treatment or just future observation.

Blood Pressure  Apps

When is high blood pressure an emergency?

Ideally blood pressure should always be less than 140/90 and in a prefect world less than 120/70 would be even better, but what do you do when the numbers are higher than they should be? When is it time to sound the alarm?
With many patients now owning home BP machines its not uncommon to get a call from an alarmed patient when they find their BP is 180/100. Obviously that is higher than it should be but its not necessarily an emergency. In truth, its not usually the number that determines if BP needs to be treated as an emergency. The condition of the patient is far more important.

BP readings that are too high will increase the risk of stroke and heart attack but not usually in the short term. There is a general misconception among most people that high BP causes the blood vessels to rupture like an over-inflated balloon and that this is how it causes a heart attack or stroke. In fact this is not what usually happens. High BP causes damage to blood vessels over many years by causing increased inflammation in the vessel walls which increases development of plaques and weakens the walls. Because these changes take a long time to develop, elevated readings do not usually need to be treated as an emergency. That doesn't mean they should be ignored, but elevated readings without any associated symptoms ( discussed below) can be addressed non-urgently and medications or lifestyle changes should be used to gradually bring readings within the desired range.

In some cases poorly controlled BP is a true emergency. Again, this has far less to do with the  readings and much more to do with how the patient is doing. Patients who have sudden onset of chest pains, stroke like symptoms, or evidence of kidney failure need to be treated emergently with rapid reduction of BP to more normal values. Situations such as this should never be treated on an outpatient basis. Hypertensive emergencies require in-hospital treatment with close monitoring to avoid permanent damage.

The important message here is not to be alarmed by the numbers. A BP of 180/100 in a patient with no symptoms is of concern but not alarming, while a BP of 140/90 that is accompanied by chest pain or confusion merits an urgent trip to the emergency room.

If the reading on your home machine is higher than usual but you are otherwise feeling OK don't panic. Take several readings. If they are all higher than usual call your doctor and let them know so they can advise you on proper management and follow up. If on the other hand you are having chest pain or symptoms such as confusion, slurred speech, weakness or loss of function on one side of the body, blurred vision or loss of vision call EMS and go straight to the nearest emergency room.