The concept of high blood pressure as a clinical diagnosis began to be accepted at the beginning of the last century, correlated with the invention of the blood pressure cuff. It turns out that the pressure of blood in the arteries, when elevated, can lead to heart attacks, strokes, aneurysms and kidney failure and can be an indication of other serious medical illnesses including tumors of the adrenal gland and pituitary as well as narrowing of the blood vessels to the kidneys. Controlling the blood pressure has been effective in reducing heart attack and stroke rates, historically. Blood pressure elevations are usually related to genetic factors as well as obesity, high salt diet, excessive alcohol intake. Lifestyle changes to reduce salt intake and obesity and increase activity significantly reduce blood pressure. The first consistently tolerable blood pressure medicine was produced in the late 1950's and that class of medications (thiazide diuretics) is still one of the most widely used and effective ones available.
There are many classifications of drugs that can lower blood pressure and the production of new ones has been a staple of the pharmaceutical industry for many years. Since blood pressure medications frequently have unpleasant side effects or don't lower the blood pressure very effectively, it was easy to produce new drugs that promised superior blood pressure lowering effects or less side effects or a more convenient dosing schedule. A pleasingly simple and mutually enjoyable office visit for a patient and primary care physician in my experience included measuring the blood pressure, finding it to be just a bit too high, going to the sample closet, finding an attractively packaged new blood pressure medication with the placebo effect still firmly attached to the brightly colored capsules, giving it to the patients with instructions to come back in two weeks to see how well it worked. Unfortunately the shiny new medications were ridiculously expensive and usually too new to have been extensively tested to determine if they actually worked to reduce the target issues, stuff like strokes, heart and kidney damage, as opposed to just lowering the blood pressure. Guidelines emerged from organizations such as the National Heart Lung and Blood Institute (NHLBI) to address which medicines to use and what blood pressure was too high and which patients to treat. There has been abundant research on blood pressure control and outcomes in different populations, fueled by both drug companies which wanted to prove their new blockbusters to be effective and experts in the field who wanted to find out what actually worked. Committees have attempted to digest this research, some good and some suspect, and come up with recommendations to guide practice.
This week the Journal of the American Medical Association published the Joint National Committee's eighth set of guidelines, ten years after the last set of guidelines came out. Guidelines are taken quite seriously by physicians and now by the people who pay us, who often scrutinize our adherence to them as a basis for performance based pay. These guidelines were 5 years in the making, I read, and were scrupulously discussed, based only on randomized controlled trials, and were delightfully succinct. There were three editorials in the same issue, generally approving them, though admitting that there is room for debate and improvement.
Briefly, and it is possible to be brief with these recommendations, the new guidelines recommend:
- Treat all patients over the age of 60 with lifestyle recommendations plus medications if their blood pressure is over 150 systolic or 90 diastolic, aiming for a blood pressure just below this goal. Previous guidelines recommended a goal of 140/90 in this group. Patients who feel fine and are on medications with blood pressure significantly below this goal may remain on the same medications.
- Patients between the ages of 18 and 60, start treatment with lifestyle measures and medications if the blood pressure is over 140 systolic or 90 diastolic, with a goal blood pressure of under 140/90. This same recommendation is true for patients in this age group with diabetes or kidney disease (which increase the risks associated with hypertension.)
- Use drugs in only 4 classes to start, including diuretics, angiotensin converting enzyme inhibitors or angiotensin receptor blockers or calcium channel blockers such as diltiazem and amlodipine. Beta blockers are absent from the list of recommended drugs because of one well done study which showed an increase in death for patients on beta blockers, primarily due to strokes. Drugs can be started singly or in combination. For African Americans use only thiazides or calcium channel blockers unless they have significant kidney disease, in which case angiotensin active medications are probably effective. Be sure to use doses of these drugs that are adequate but not toxic (there is a nice table.)
- For patients with blood pressure above the goal after starting initial therapy, add another of the drugs in one of the 4 classes, but do not combine angiotensin receptor blockers with angiotensin converting enzyme inhibitors. If blood pressure still is not controlled, drugs in another class may be added, though it is unclear from evidence that this will make a difference in outcome.
These recommendations are not meant to entirely squelch creativity and do not address control of blood pressure in patients who have established heart disease, who may take other medications that control issues other than just the blood pressure and may interact with blood pressure medications.
I am generally very happy with these new guidelines. The fact that blood pressure goals for patients over the age of 60 are looser will significantly reduce the burden of treatment for these people, and reduce the number of fruitless visits in which both patients and physicians feel like failures because a number refuses to climb as low as we would wish. The standardization of blood pressure goals for patients younger than this, returning to the historical 140/90 as a goal of treatment will also simplify things. The treatment of blood pressure with reduction of disabling strokes and heart attacks that has been associated with this is a major success of modern medicine and simplifying treatment will probably make both patients and physicians more motivated to do it right.