Alcoholism: Hypertensive Effects of Heavy Drinking
Guest: Dr. Peter Miller – Psychiatry & Behavioral Sciences
Host: Dr. Linda Austin – Psychiatry
Dr. Linda Austin: I am Dr. Linda Austin. I am interviewing Dr. Peter Miller who is Professor of Psychiatry in the Behavioral Sciences here and a psychologist by discipline. Dr. Miller is a researcher in the area of substance abuse and, in particular, alcoholism.
For now, we are going to be focusing on the relationship between hypertension and alcoholism. Dr. Miller, welcome. Tell us what your studies have shown about that relationship.
Dr. Peter Miller: Certainly. Actually, a lot of people know a little bit about that. They know more about the fact that if you drink a little bit, it actually reduces your cardiovascular risk factors, and a little bit of drinking can also reduce blood pressure. But when people start to drink heavily, and what I mean by that is about three or more drinks a day, then we find that it has an increasing effect on blood pressure and it can really cause a problem.
Dr. Linda Austin: And is that three drinks whether it is men or women and regardless of your size?
Dr. Peter Miller: Well, we are not quite sure but what we recommend for women is that they try to drink no more than about seven drinks a week, or one drink a day. With men, it is 14 drinks a week, or two drinks a day. But it seems like three or more drinks a day for whoever is the magic number. When you get over that, we see increases in blood pressure.
Dr. Linda Austin: Now define a drink because certainly what is considered a drink is in the eye of the beholder, the gullet of the imbiber. What exactly is a drink?
Dr. Peter Miller: I think it is a little bit of both of those, depending on how heavy of a hand you have. A drink is normally defined as one can or bottle of beer, so 12 ounces of beer. In some bars they might serve you a pint, so that is 16 ounces, so that is a little more than one drink. About five ounces of wine, which is the amount of wine in a normal-sized wine glass, not one of the big goblet wine glasses, and one and a half ounces of hard liquor. But if somebody is pouring themselves a liquor drink in the night using a shot glass, or not measuring it out, they may actually be having two drinks instead of one. So, we have to ask people very carefully about that. And before we ask patients how many drinks they have, we always define that for them so they know what we are talking about.
Dr. Linda Austin: Let’s talk about subpopulations now. Who might be particularly vulnerable to the hypertensive effects of alcohol? Who do you worry about the most?
Dr. Peter Miller: Well, we worry about age as a factor. About 50 percent of people over 60 are diagnosed with hypertension, so it is a big group. There about 60 million people in the United States with high blood pressure and about 10 million of them drink too much. As people age, they are more sensitive to the effects of alcohol and they are more prone to hypertension, so we have to worry about that. We also worry about African-Americans because they are more prone to hypertension. But, on the other hand, with Caucasians, there is what we call a J-shaped curve with the relationship between alcohol and hypertension, so that a little bit of drinking actually helps you but then as you drink more, it increases your blood pressure. With African-Americans, it does not seem to work that way. A little to a moderate amount seems to increase their blood pressure, and heavy drinking does as well, so they tend to be more alcohol-sensitive. We are not quite sure why that is but it means that we need to talk to African-American patients a little bit more about their alcohol use when we are treating them for blood pressure.
Dr. Linda Austin: Is it fair to say then that it becomes one more risk factor that may not be an issue when you are 30 or 40? You may not even see the effect at 30 or 40 but then as you get older, the more susceptible you are to hypertension.
Dr. Peter Miller: That is definitely true, yes. Actually, if you look at somebody’s drinking, if they are a heavy drinker, say, in their 30s and 40s and we follow them up, we can almost predict that they are more prone to hypertension as they get older. So that is certainly a factor that we have to take into account.
Dr. Linda Austin: So then if a person is drinking and they have hypertension, does their hypertension become more difficult to control with medications, if they are drinking?
Dr. Peter Miller: Yes. That is a great question. We talk about what is called treatment resistant hypertension. That is somebody who is on, say, two or three anti-hypertensive medications and their blood pressure still is not under control. In fact, 70 percent of people in treatment for hypertension do not have their blood pressure under control. They have not reached goal for a variety of reasons. They may not be taking their medication properly, whatever. But one of the six major reasons for treatment resistant hypertension is heavy alcohol use. So, physicians are now getting used to asking patients about that, not only are you taking your medication, are you watching your salt intake, are you getting exercise, and maybe about their weight as well, but they are also asking about alcohol use.
Dr. Linda Austin: Just to review, why is hypertension such a problem? What are some of the really significant health events that it can lead to?
Dr. Peter Miller: Well, one of the main health events is stroke and that is a major problem we worry about: stroke, heart disease, those kinds of things. There is a lot of undiagnosed hypertension around because people do not have any symptoms when they have high blood pressure so they do not think about it. And that is a problem with medication as well. If a physician says your blood pressure is too high, take this medication, you take it but you do not really feel bad because of your hypertension so you may not take it like you are supposed to.
You know, it is partly genetic, partly lifestyle. It is related to smoking. It is related to alcohol use, as we have been talking about. It is related to obesity. Inactivity is another factor. And then if you have the genetic predisposition, it just adds to that.
Dr. Linda Austin: Are scientists beginning to understand what the mechanism of action is, that is, exactly how alcohol does lead to hypertension?
Dr. Peter Miller: Again, we really do not know the answer to that. There may be a number of factors. Some people seem to be more alcohol-sensitive and that may be due to genetics. Obviously alcohol affects physiological mechanisms so that your body is not as responsive to trying to lower your blood pressure. It affects what are called baroreceptors in your blood vessels so that they do not work like they are supposed to, to lower your blood pressure when it needs to be lowered. And even behavioral factors, because when someone drinks a lot, they are not as good about taking their medication properly and watching their salt intake; they do not take care of themselves as well. So it is a combination of factors.
Dr. Linda Austin: Dr. Miller, thank you so much for talking with us today.
Dr. Peter Miller: Thank you.
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