If David Letterman were to make a Top Ten list called: "Things that Doctors do that Really Matter," treating hypertension would certainly make the cut. Hypertension is highly prevalent within our society, with about one in three U.S. adults affected. The relationship between blood pressure and cardiovascular risk is continuous and independent of other cardiovascular risk factors. Treatment of hypertension has been demonstrated to reduce risk of stroke by 35 to 40% and risk of myocardial infarction by 20 to 25%. If you are reading this thinking, "but I've always had low blood pressure," here's some cheerful news: 90% of adults who have normal blood pressure at age 55 will develop hypertension as they age. Thus, the detection and appropriate management of elevated blood pressure is one of the most important tasks in the practice of providing primary care to adult patients.
Those of us who treat hypertension hopefully have heard of the Joint National Committee (JNC) guidelines on hypertension. The latest set, "JNC 7," came out in 2003. Since 1978, when the National Heart, Lung and Blood Institute (NHLBI) formed its first multidisciplinary panel (JNC 1) to review the evidence and formulate its summary, these guidelines have been the major clinical practice rule set governing appropriate treatment of hypertension. It's been nearly a decade and JNC 8 is expected to be released in the spring of 2011.
Recently I had the pleasure of listening to a talk at the Georgia Chapter meeting of the American College of Cardiology by Dr. Keith Ferdinand, Clinical Professor of Medicine, Division of Cardiology at Emory and Chief Science Officer of the Association of Black Cardiologists. Dr. Ferdinand, who has served on previous NHLBI JNC committees reviewed the last decade of data that is likely to impact the newest set of hypertension guidelines.
Some of my take home points from this talk are listed below:
Evidence supports the treatment of hypertension in octogenarians. Patients treated with indapamide (a diuretic) with or without perindopril (an ACE inhibitor) had 30% reduced risk of stroke and a 21% reduced risk of death from any cause.
The blood pressure treatment goal for diabetic patients may be revised, based on the ACCORD intensive blood pressure lowering trial, to less than 140/90 (currently less than 130/80). ACCORD found no cardiovascular benefit for the primary endpoint with more aggressive lowering of blood pressure (to less than 120 systolic versus less than 140 systolic) in high risk hypertensive diabetic patients.
ACCORD did find a small reduction in a secondary endpoint, total stroke and non-fatal stroke, in study participants treated to the more aggressive blood pressure goal. In addition the placebo group in ACCORD was noted to have on average relatively well controlled blood pressure.
The ONTARGET trials found that there is not good evidence to support either renal or cardiovascular benefit from the combined use of ace inhibitors with ARBs for high risk patients. These randomized controlled trials looked at ramipril, telmasartan, and their combined use with respect to renal and cardiovascular outcomes.
In refractory hypertensive patients, spironolactone 25 mg should be considered as an additional agent.
Amongst the class of thiazide diuretics there may be differences amongst agents and their prescribed dosages in terms of efficacy for cardiovascular risk reduction. The longer acting chlorthalidone may be more effective than the shorter acting hydrochlorothiazide. Some of the most widely cited studies providing evidence for the use of thiazides as first line treatment for hypertension are based on study of chlorthalidone or using higher doses of HCTZ (50 mg) than those normally prescribed.
The combination of ACE inhibitor (benazepril) and dihydropyridine calcium channel blockers (amlodipine) may be superior to the ace inhibitor and diuretic (hydrochlorothiazide) combination for hypertension treatment (ACCOMPLISH).
Atenolol is falling out of favor, with a relative lack of evidence supporting its use as a first line therapy for hypertension. More attention is likely to be given to beta blocker selection on the basis of demonstrated cardiovascular outcomes (metoprolol, carvedilol) in JNC 8.
As a primary care physician I found it very useful to hear Dr. Ferdinand's opinion about what's to come with respect to JNC 8's hypertension guidelines. I already will be changing some of my practice based on this knowledge. I look forward to reading the guidelines and hearing the reaction of experts in the spring of 2011. It appears as though with hypertension, as with other fields of medicine, there will be a growing emphasis on specific drug and dose selection as opposed to class of drug selection.
Juliet K. Mavromatis, FACP, is a primary care physician in Atlanta, Ga. Previous to her primary care practice, she served on the general internal medicine faculty of Emory University, where she practiced clinical medicine and taught internal medicine residents for 12 years, and led initiatives to improve the quality of care for patients with diabetes. This work fostered an interest in innovative models of primary care delivery. Her blog, DrDialogue, acts as a conversation about health topics for patients and health professionals. This post originally appeared there.