Disparities in Hypertension: Let's Get Genes Out of the Way and Talk Social Determinants

Henry R. Black, MD; Keith C. Ferdinand, MD


May 18, 2010

This feature requires the newest version of Flash. You can download it here.

Henry R. Black, MD: Hi, I'm Dr. Henry Black. I'm the immediate past president of the American Society of Hypertension [ASH], a clinical professor of internal medicine at the New York University School of Medicine, and member of the Center for the Prevention of Cardiovascular Disease at the institution.

I'm talking to you today from the 25th anniversary annual meeting of the American Society of Hypertension in New York City in May. I'm here today with Dr. Keith Ferdinand, my colleague on JNC6 [Sixth Report of the Joint National Committee on Prevention, Detection, Evaluation, and Treatment of High Blood Pressure], a member of the ASH Board of Directors, clinical professor of medicine at Emory, and the Chief Scientific Officer of the Association of Black Cardiologists.

Keith, you've been one of the leaders in pointing out diversity and disparities in treatment of different groups. Do you care to talk a little bit about what you meant by that and what's going on?

Keith Ferdinand, MD: Well, it's reasonable to look at how different subpopulations act in terms of the prevalence, severity, and response to treatment. Now we know there's only one human race, Homo sapiens. We're all basically the same, but there may be some nuances in how people eat, live, and respond to medications, and that's what we usually are looking at.

Dr. Black: What do you think is the major reason for that? Is it environment? Is it care? Is it biological things?

Dr. Ferdinand: Let's get genes out of the way. I don't think genes explain much of the disparities because there are too many diseases -- from infant mortality to certain cancers to hypertension, stroke, diabetes. It's just a wide range of conditions that are disparate within our society. There may be some genetic factors. There are some polymorphisms related to self-preservation that say that certain people of African descent may respond more to a higher-salt diet or sodium load. And that may explain some of the response to diuretics. There are even some studies looking at amiloride, which is a spironolactone-type active agent, and it seems to be more responsive in the black population. With that being said, the main reason you see in the African American population more cardiovascular disease, more stroke, more kidney disease is because you have hypertension that starts earlier in life. It's poorly controlled with more target organ damage, and that's related to what we call the social determinants of health. It's a term that some of the people in public health use. It means living in a poor neighborhood, eating a high-sodium diet, less potassium in your diet, more obesity, less physical activity, more psychosocial stress, less access to healthcare. And some of those determinants override any genetic differences across populations.

Dr. Black: Have we made any progress?

Dr. Ferdinand: We've made some progress. As you know with the National High Blood Pressure Education Program starting in 1972, we've seen a gradual decline in coronary heart disease and stroke and increase in control in blood pressure. But there still remain gaps, and the gaps are not necessarily just in awareness, and they may not even be in treatment, but they're in response.

Now how would that be? If a person has hypertension that starts earlier in life and that person does not control the blood pressure, you actually have remodeling of the vessels with smooth muscle hypertrophy. You could have stiffening of the major arteries of the vessels, such that when that person responds to medications it may be less than a person who has newly diagnosed hypertension. So blood pressure begets blood pressure, hypertension begets hypertension, people who have hypertension and don't treat it become more difficult to treat later in that process.

Dr. Black: You've been a major leader in the ASH Outreach Program, which we just had, I think, a very successful experience [with] in New York City. Tell us about that.

Dr. Ferdinand: Well, it's been a wonderful experience, in your presidency and prior to that, Suzanne Oparil['s], and I'm sure George Bakris is going to continue as part of our mission. We are here as a professional society to educate physicians, clinicians, and others and hypertension specialists, but part of our mission is to educate the population. We want patients to be a partner in their care, starting in New Orleans in 2008. In that hurricane-ravaged city we were one of the first major organizations to go back to New Orleans, and it was somewhat adverse to the organization because many people didn't want to go to that environment, but we felt it was important to not only educate ourselves but to educate the population. We went to the clinics, we went to senior citizen centers, we had a major screening. People lined up for blocks to get their blood pressures checked, their glucose checked. We repeated this in San Francisco in 2009 and presently in New York City, where we're going to be for the next 3 years, and this is the ASH headquarters.

We've actually gone to the Hispanic populations, African American populations, and even at our host hotel, the Hilton Hotel, and screened, educated, and intervened. I don't like to just say "screened” because that's a little superficial. We had a wonderful brochure that we handed out that talked about hypertension in a very sensitive manner at a literacy level which most people can accept, about sixth- to eighth-grade level. It sounds low but that's where many people read. We often look at hypertension as a disease which is very complex, and we as hypertension specialists know that the nuances of it are difficult at times to comprehend, but the basic things, know your numbers. What is prehypertension? What is stage 1, what is stage 2? What lifestyle modifications are beneficial? That's what we try to teach in the booklet. We don't want people to become mini-doctors, M-I-N-I, small doctors. We want them to become partners in their care. So the ASH Outreach has been a successful means, but ASH has used its mission not just to educate professionals but to educate the community.

Dr. Black: Do you agree that hypertension is a neglected disease?

Dr. Ferdinand: That's a wonderful concept. The Institute of Medicine [IOM] actually published that in February of this year, 2010. By neglected disease they meant it's similar to some of the diseases endemic in tropical countries, where you have a disease like Chagas disease, which is readily identifiable, easy to treat, but often overlooked and not done because of social and poverty-related problems. So hypertension to some extent -- not by ASH and certainly not by you with the programming that you've been doing -- but by many clinicians is overlooked. They kind of take it for granted. "Oh, your pressure is a little bit up," you say, "Well, Mrs. Brown, your blood pressure is 160 over 95." "Oh baby, that's just my pressure. It's been like that for years." That is a neglected disease. That is a condition in which you have what's called clinician inertia, where the doctor, because the patient is relatively asymptomatic -- they may actually have some fatigue or headaches or something but relatively asymptomatic -- starts to accept poorly controlled blood pressure as the norm and does not do anything to change in terms of increase in medicines, adding a diuretic, adding a long-acting calcium-channel blocker that may actually control blood pressure.

Fortunately ASH was ahead of the curve. Before the IOM report that talked about the need for public health to address hypertension, we've been doing that. The New Orleans effort was 2008, that was 2 years. San Francisco was 2009. So we had already made the decision as an organization that the public health approach to hypertension was the right way.

Dr. Black: One of the recent interpretations of the ACCORD [Action to Control Cardiovascular Risk in Diabetes] study, which I'm sure you're very familiar with, was that we don't have to treat hypertension aggressively. It's not going to matter.

Dr. Ferdinand: That was terrible! And if you were at ACC [American College of Cardiology meeting], and I was with you at that time, the message came out in all of the leading journals, like USA Today and New York Times, that treatment of blood pressure doesn't make a difference. That wasn't the right message. Those persons who got to more rigorous levels of a blood pressure of 119 did have a benefit, and one of the benefits was a decrease in fatal and nonfatal stroke. Now that's not the primary endpoint and trialists like to make a big deal out of the primary endpoint, but if I was in the group that had less strokes I would be happy, and if I was in the group that had more strokes, I would consider that adverse. So there were some benefits.

The other thing is this: if you have a goal for blood pressure, that doesn't mean that you have to drive people down to the "normal" of less than 120, but it means you have a target -- something that you search for. If you keep that goal high, for instance for diabetics and people with kidney disease, and say let's move it back to 140, then most people are going to be above that goal. So I would keep the goal at 130 for diabetes and renal disease.

Dr. Black: I think it's a little behavioral trick we guideline writers sometimes play on the public and on the doctors, and we set a goal appropriately. If you set it too high no one is going to get there and they'll ignore you. If you set it too low, well, you can't. You're going to feel you've accomplished something when you really haven't. I think it's like sports. I'm sure Ted Williams, for those of you who remember him...

Dr. Ferdinand: I know about that.

Dr. Black: ... planned to get a hit every time he was up. The best he could ever do was 40.6%, but his goal was still 100%.

Dr. Ferdinand: Right.

Dr. Black: Michael Jordan planned to make every shot. He made about half of them, but the goal was appropriate.

Dr. Ferdinand: And people who really know sports know that Ted Williams could have been under 400 in his last year if he had not batted what he did. I think it was like 3 for 5 that day.

Dr. Black: That last day, right.

Dr. Ferdinand: And he felt strong enough about his commitment to doing the right thing as an athlete that he was going to play and he was going to play well and he was going to stay over 400.

Dr. Black: That's right.

Dr. Ferdinand: So that's what we need to do as clinicians. We can't look at these nuances and studies and then give these simple headlines to our patients [that] treating blood pressure doesn't make a difference. Boy, that's wrong!

Dr. Black: I think we -- it's our responsibility to counter that publicity, which is uneducated and potentially dangerous.

Dr. Ferdinand: It feeds into physician inertia. It also feeds into the culture. Let's look at some of the racial-ethnic populations. For instance, Mexican-Americans in NHANES [National Health and Nutrition Examination Survey] have the worst blood pressure control. Why is that? Less access, less insurance, Spanish speaking becomes a barrier. And, I should have mentioned that the ASH brochure has been translated into Spanish, and we're going to look at translating it into Chinese, because we think it's important for people to see a language that they understand. Now it's easy to say, well, we're all Americans. Everybody should speak English. Well that's true to some extent, but if you're going to reach a patient you need to reach that culture.

Dr. Black: Right.

Dr. Ferdinand: That environment, that language or it becomes a barrier.

Dr. Black: We have to be culturally sensitive. We've got to understand what people do.

Dr. Ferdinand: Sure.

Dr. Black: Patients have to be our partners.

Dr. Ferdinand: Absolutely.

Dr. Black: Industry has to be our partner.

Dr. Ferdinand: Absolutely.

Dr. Black: Societies have to cooperate. Hypertension is the most important of the risk factors we have, and we're not neglecting it, and I certainly hope people don't as well.

Dr. Ferdinand: I think for African Americans the important message is know your blood pressure, treat your blood pressure, but you also have to change your lifestyle. This love of high-salt, high-fat foods -- we need to get over that and need to embrace a more healthy lifestyle. In fact, as you know, the DASH [Dietary Approaches to Stop Hypertension] diet -- which was a clinical study, not an environmental study -- but [with]the DASH diet, which is high in fresh fruits and vegetables and low-fat dairy products, African Americans in the DASH trial did the best.

Dr. Black: Did extremely well. Thank you very much, Keith.

Dr. Ferdinand: My pleasure.