Treating Hypertension Part I: The Silent Killer

Hypertension, commonly referred to as a “silent killer,” remains a major figure in the long list of clinical issues facing patients and clinicians. According to the Centers for Disease Control and Prevention, approximately one in three adults in the US has the condition, with the risk increasing with age so that upwards of three quarters of individuals over the age of 70 are affected by it. Of those who have high blood pressure, more than one in five is unaware, and of those receiving treatment, 30% are not adequately controlled. Untreated or uncontrolled hypertension can increase the risk of stroke fourfold to sixfold and the risk of heart failure twofold in men and threefold in women. It can also lead to heart attack, kidney disease, and retinopathy.

Given the high prevalence of hypertension as well as the varied mechanism of action of the available anti-hypertensive agents, individualized treatment of the condition is imperative in order to obtain optimal outcomes. Continuing education of both the provider and the patient is necessary to ensure that appropriate care is achieved. Among the questions that arise for primary care physicians in treating hypertension are:

• How can clinicians and patients be encouraged to produce better results in treating hypertension?
• Should blood pressure goals be more ambitious for those most susceptible to hypertension, such as African Americans, or those with significant comorbidities?
• How are guidelines for treating hypertension likely to change in the near future?
• Which class of anti-hypertensive drugs (and which drug within a given class) should be used first and when should combination therapy be instituted?

To answer these questions and more, MD Magazine: Peers & Perspectives recently convened an expert discussion on managing hypertension featuring three of the nation’s leading hypertension specialists: Jan Basile, MD, professor of medicine in the division of general internal medicine/geriatrics at the Medical University of South Carolina;  eith C. Ferdinand, MD, adjunct clinical professor at the Morehouse School of Medicine; and Karol E. Watson, MD, associate professor of medicine in the division of cardiology at UCLA. The panel was moderated by Peter Salgo, MD, professor of anesthesiology and internal medicine at Columbia University.


Current Standards of Hypertension Treatment

Salgo opened the discussion by asking whether it is correct to assume that clinicians generally recognize that hypertension is a key risk factor for cardiovascular and  metabolic disease.

Awareness of the dangers of hypertension is not the problem, replied Basile; dealing with the condition effectively is. “Clinicians have been educated in medical school  and throughout their careers on the ravages of hypertension,” he said. “A lot of the issues have to do with the difficulty in getting blood pressure effectively controlled, and a lot of that has to do with the systems that are in place to effectively control it.”

Watson agreed that the threat of hypertension has been impressed upon both medical professionals and patients. “I really do think the public health messages are  getting out,” she said. “By now, pretty much everyone knows that hypertension is bad.”

However, Ferdinand countered that not everyone fully appreciates the urgency of treating high blood pressure. “Although it’s really easy to diagnose and often easy to treat, we still are not doing all that we can to control hypertension,” he argued. “Sometimes there is a laissez-faire attitude in both the public and physicians about hypertension since we presume that the message has been delivered so effectively.”
 

“One out of five people in this country are unaware they have hypertension, and lots of people with the diagnosis are not well controlled,” noted Salgo. “What’s missing? What are we doing wrong?”

The numbers have improved a great deal since 1988 when NHANES (National Health and Nutrition Examination Survey) data was first published, pointed out Basile, so that 69% of those who are being treated for hypertension have gotten their blood pressure under 140/90. The obstacles to greater success, he added, have to do with the systems designed to treat hypertension.

Among the changes Basile recommended were involving family members to help ensure that patients stick to their treatment; providing home blood pressure monitors to patients; keeping track of whether patients have filled their prescriptions via e-script writing; and using non-physician providers so patients can be monitored more  frequently. “Care of people with hypertension is far more than just a face-to-face interaction the day of the appointment,” he said.

Salgo asked, how accurate a sense do physicians have of their success at treating patients with hypertension?

“There’s evidence that as clinicians we have an inflated opinion of how well we are controlling blood pressure,” said Basile, pointing to a study in the American Journal of Medicine that found that physicians at three VA hospitals estimated that 68% of their patients with hypertension were under control, whereas electronic medical records  showed that just 43% were under control.¹

To establish some context for the discussion, Salgo asked for a definition of hypertension and pre-hypertension, as well as an explanation of what it means to give a diagnosis of “pre-hypertension.”

Watson explained that, according to JNC 7 (The Seventh Report of the Joint National Committee on Prevention, Detection, Evaluation, and Treatment of High Blood  Pressure), hypertension is defined as systolic blood pressure over 140 mm Hg and diastolic blood pressure over 90 mm Hg, and pre-hypertension is defined as systolic between 120 and 139 mm Hg and diastolic between 80 and 89 mm Hg.

“With pre-hypertension, we are looking at someone who is going to progress to hypertension unless we do something,” Watson said. “What we need to get patients and providers to understand is that this can be managed before it gets to the point of frank hypertension, which then leads to heart failure or renal failure or something very dire down the road.”

Different Goals for Different Patients? 

Given that African Americans are at particular risk for hypertension and cardiovascular disease, Salgo asked whether blood pressure goals should be different for them. “The ISHIB [International Society on Hypertension in Blacks] Working Group, of which I was a member, does suggest reducing blood pressure to lower numbers in African Americans, but that was not embraced by the JNC 7 and probably will not be embraced by JNC 8,” said Ferdinand, explaining that the group felt the more ambitious goals were warranted due to the heavy toll hypertension takes on African Americans. This includes dialysis rates three times the average, a 40% greater risk of stroke, and  increased rate of death from heart failure. “We suggested, ‘Why wait until we have more death and disability in African Americans? Let’s treat them more intensively.’”

“For somebody with other comorbidities, would you aggressively treat prehypertension, whereas with somebody who’s got no other risk factors, you might just watch it?” asked Salgo.

“You’ve actually hit on what’s going to be a very controversial area of discussion going forward and may actually change from JNC 8 versus JNC 7,” said Ferdinand. He  pointed out that JNC 7 set a goal of lowering blood pressure to under 130/80 for patients with diabetes and kidney disease, but that subsequent trial results have failed to demonstrate a significant benefit from reaching this goal. “The ACCORD [Action to Control Cardiovascular Risk in Diabetes] hypertension trial, which lowered blood  pressure intensively in patients with diabetes, was unable to show in the primary end point of combined cardiovascular disease a benefit from getting the systolic blood  pressure down to approximately 119 mm Hg versus 133 mm Hg from a starting baseline of 139.”

The ACCORD blood pressure trial included 4,733 people aged 40 to 79 with type 2 diabetes mellitus and high cardiovascular risk who were randomly assigned to  receive intensive blood pressure control (with a systolic blood pressure goal of under 120) or standard blood pressure control (with a systolic blood pressure goal of  under 140).

Participants started with an average systolic blood pressure of 139.2. At the end of the trial’s first year, those receiving intensive therapy were down to 119.3,  and those receiving standard therapy were down to 133.5 At the end of the nonblinded trial, in June 2009, the mean duration of follow-up for the primary outcome of  combined nonfatal myocardial infarction, nonfatal stroke, or cardiovascular death was 4.7 years. Compared with those in the standard-therapy group, those in the intensive-therapy group did not have a statistically significant difference in primary outcome, but they did have a significantly higher rate of serious adverse events attributed to anti-hypertensive treatment.²

Nonetheless, Watson pointed out that the ACCORD trial did find some specific benefits from getting systolic blood pressure below 120 compared with getting it below  140. “They found that the overall composite cardiovascular outcome was not significantly reduced, but there was a statistically significant reduction of almost 40% in the  pre-specified secondary outcome of stroke,” she said. “In all patients, stroke is a very important outcome we are trying to prevent, and in some patient populations, such as  African Americans, stroke is even more prevelant. So there are definitely some clinical situations where targeting a blood pressure to a lower goal would make sense.”

References
1. Steinman MA, Fischer MA, Shlipak MG, et al. Clinician awareness of adherence to hypertension guidelines. Am J Med. 2004;117(10):747-754.
2. The ACCORD study group. Effects of intensive blood-pressure control in type 2 diabetes mellitus. N Engl J Med. 2010;362(17):1575-1585.

To read the second part of this expert discussion, "Lifestyle Modification and Treatment Guidelines," click here. To read the third part, "Pharmacologic Management of Hypertension," click here.