Archive for the ‘Hypertension’ Category

team-based home blood pressure control

Wednesday, July 10th, 2013

I was reading the July 3, 2013 edition of JAMA and came across an article and an editorial on better ways to manage elevated blood pressure (BP). The basic concept stems from data reviewed by the CDC in a 2012 online publication: high BP, AKA hypertension, is a major risk factor for both stroke and cardiovascular disease which jointly are the number one causes of preventable death in the United States.

Check your blood pressure and let your healthcare team know the reading

Check your blood pressure and let your healthcare team know the reading

Do you know what your BP is? Let's start from scratch with the kind of numbers you might hear about when you see your doctor or have your BP checked in other settings (e.g., the grocery store we usually shop at has a free automated system for BP measurement).

My BP usually runs about 116/ 68, but, similar to yours and everyone else's, my BP varies from those numbers from minute to minute. The top number, called my systolic pressure is always higher than the lower (diastolic pressure) It measures pressure in my arteries when my heart contracts (beats) while the bottom number measures it between heart beats when that muscular organ is resting and refilling with blood about to be pumped out to the rest of my body. The American Heart Association has a nice webpage explaining BP.

I'd like to see BPs under 120/80 and that seems to be a reasonable consensus figure in articles I read. Hypertension (HTN) is conventionally defined as a BP higher than 140/90 and the National Heart, Lung and Blood Institute's website calls any BP between 120/80 and 140/90 prehypertension. That's new to me, as the designation used to be applied to those with BPs between 130 and 139 for the upper number and 85 to 90 for the lower one. But I retired in 1998 and the BP goals changed in 2003.

My 2006 copy of Kaplan's Clinical Hypertension, the ninth edition of this amazing, mostly one-person work by a senior professor in Dallas (I just ordered a used copy of the 2010 tenth edition), mentions that 120-129/80-84 used to be considered normal  and 130-139/85-89 was thought to be borderline. But the 2003 report of the Seventh Joint National Committee  put BPs anywhere over 120/80 into the new category saying it wasn't a disease, but a designation to identify those at high risk of developing hypertension.

So what if one of your numbers is in this range, but not the other? The Harvard Medical School's Family Health Guide article on prehypertension notes that BPs vary from time to time and from arm to arm. If you have BP numbers over 120/80, the classification will depend on your average/usual readings, not the extremes. They suggest you always use the systolic or diastolic number that puts you in a higher category (normal, prehypertension, hypertension).  So, for example, if your average is 124/76 or 118/83, you're in the prehypertensive group

The CDC paper and others say the overall prevalence (i.e., the proportion of a population having a disease) of HTN in America is ~30%, but that increases with age with many estimates stating it's 70% in those of us 65 and older. That group is more prone to systolic HTN with only the upper number being elevated. That's still high BP and dangerous.

Treatment of HTN with diet, weight control and meds is associated with considerable decreases in the dire consequences of uncontrolled HTN: strokes, heart attacks and congestive heart failure (a condition where your heart can't pump out enough blood to keep up with the needs of your body).

All of us should be screened for HTN, even if our BP is less than 120/80. Screening intervals should be at least every two years for those with normal BP and every year for people with prehypertension. Your physician will also consider your other risk factors (weight, age, gender, your blood lipid levels {e.g., total cholesterol, HDL and LDL levels} presence or absence of diabetes, heart disease or chronic kidney disease, exercise patterns) and may, in some case recommend drug therapy even if your BP is <140/80. That's especially likely for those with any of the three chronic diseases I just mentioned.

So do we all need to be on medications if our BP is >140/80 (no, your physician may start with non-pharmacologic modalities such as cutting our salt intake) and if we do start on BP meds how often do we need to see our doc? After all, they're really busy these days and we may not be able to get an appointment for several months.

Let me start with my own experience (in the "Dark Ages") and then come up to the present.

When I was in my first Air Force assignment at Langley AFB, VA from 1970 to 1972, I set up a HTN clinic run by a public health nurse, an RN with extras training who didn't want to be a ward nurse. My immediate boss was a cardiologist and, after I set up protocols (e.g., which meds to start with, appropriate followup intervals for various levels of BP, when to call for help), our nurse felt quite comfortable running the BP clinic.

She didn't see other kinds of patients, got very savvy about HTN, read a lot of the current medical literature on the subject, was entirely at ease with calling either of her two consultants whenever she had a question and our HTN patient population could easily get appointments in her clinic.

Fast forward ~forty years.

In 2011 a Veterans Administration group from Durham (coincidentally a place I worked when I was a resident and nephrology fellow at Duke) published an article in the Archives of Internal Medicine (now called JAMA Internal Medicine). Its title was "Home Blood Pressure Management and Improved Blood Pressure Control: Results From A Randomized Controlled Trial."

In brief they followed nearly 600 HTN patients who were randomized into one of four groups. The first had usual care, i.e., being seen in a primary care clinic at intervals. The other three groups involved nurses who administered behavioral management concepts, worked with docs on medication management or did both. The patients had their BPs monitored at home with data transmitted to the researchers. Incidentally 48% of the patients involved were African American.

Overall the research group felt the intervention effects were moderate, but those patients who started with the worst BP control had much better resultant effects.

there are a number of options for HTN meds

there are a number of options for HTN meds

Now there's the new JAMA article, "Effect of Home Blood pressure Telemonitoring and Pharmacist Management on Blood pressure Control: A Cluster Randomized Clinical Trial." Researchers associated with an integrated health system in Minnesota using electronic medical records, noting that typically only half of HTN patients have adequately controlled BPs, followed 450 patients, roughly half of whom got usual care. The other half got home BP telemonitoring and had PhD pharmacologists following their data and making changes in their BP meds by a protocol worked out with physicians.

BP control was better in the latter group at 6 and 12 months and was even better 6 months after the year-long study ended.

Lesson one: other healthcare professionals can manage HTN. Lesson: doing this via home BP measurements may be the path of the future.

More on salt, actually salts

Saturday, June 30th, 2012

What should we make with our CSA-supplied spinach today?

We're in the prime of our CSA delivery season; fresh vegetables started three weeks ago and fruits this week. Many of our meals consist of spinach, lettuce, beets, rhubarb, apricots & cherries, with milk and/or cheese or yogurt. We rarely, if ever, shop for any "prepared foods," always check labels for sodium content, and only eat out, other than our weekly Thai food splurge, for birthdays and other occasions. I'm firmly convinced that less sodium (often termed "table salt," but most typically found in processed foods and restaurant dishes) is better for us.

So when I started reading an article in the ACP Journal Club section of the January 2012 issues of the Annals of Internal Medicine that was titled "Review: Interventions to reduce dietary salt do not reduce mortality or morbidity," I was skeptical. The original article, published in England, was a meta-analysis, a statistical look at a group of research studies. In this case seven randomized controlled trials were lumped together, and according to the Journal Club, the conclusion was as in the article's title.

But the US and Canadian reviewers disagreed. In people with normal, borderline, or elevated blood pressure, 6 of the 7 studies showed variable results and the pooled data did not reveal statistically significant decreases in death rates or medical complications. I went to the original article and the authors actually say, "Despite collating more event data than previous systemic reviews...there is still insufficient power to exclude clinically important effects of reduced dietary salt..."

That translates, to me, as "we don't know yet what happens when millions of people lower their salt intake." The reviewers, being ultra cautious, say, "...we are unaware of compelling evidence showing that consuming less sodium in the general population is harmful."

A free-lance science writer wrote an article in Scientific American in 2011 with the title, "It's Time to End the War on Salt." She argues that the data linking increased salt intake and various diseases is not solid.

Should I believe those statistics?

Yet there are lots of studies showing a strong link between salt intake and blood pressure and others claiming a similar correlation between dietary sodium and cardiovascular disease.

One country that decided to act on these supposed connections was Finland. In the late 1970s a national-level campaign was started to include mass media education, monitoring of urinary sodium excretion and food-industry cooperation using salt substitutes. The average sodium intake was cut by nearly 30% and over the next ~24 years stoke and heart attack deaths went down by 60%. Was this cause and effect? I'm not sure, since other factors may have played a role and the initial average salt intake was quite high.

But a December, 2011, New York Times article, with the striking title, "Sodium-Saturated Diet Is a Threat for All" led me to find another kind of salt that plays a role. I found the July, 2011, Archives of Internal Medicine research report, "Sodium and Potassium Intake and Mortality Among US Adults" and realized I was on the right track with our diet.

It's not just too much sodium chloride, the kind of salt some use at their dining room tables, manufacturers add to processed foods and restaurants to their recipes to add flavor and preserve food. It's also how much potassium you eat (in fruits, juices, vegetables, fish, nuts and meat), that makes a difference. In this case, within reason and assuming you have normal kidney function, more is better.

I'm going downstairs and eat some fruit and perhaps a baked potato and yogurt, all high in potassium and relatively low in calories.

Beating the heat by using the new data:

Tuesday, August 23rd, 2011

Ready, set, eat well

A recent article in The Wall Street Journal described how the Houston Texans professional football team is using data I read in the Archieves of Internal Medicine online to improve player safety. The Texans are facing some of our worst summer heat and are going to extraordinary lengths to prevent heat-related injury.

I'm not at all sure I agree with their stategem, practicing in triple-digit weather outdoors in the full sun. Their theory is that doing so helps their players remain fresh in the heat of early-season games. Other teams have opted for temperature-controlled practice arenas or night-time workouts or cooler climes.

We'll wait and see the results, but at least they're using the latest medical research and some practical concepts.

Players are weighed pre-practice and afterwards (the team, collectively, lost an incredible average of 450 pounds per two-hour session one week). That's in spite of replacement fluids and ice to the tune of 100 gallons of water, 50 cases of Gatorade and three quarters of a ton of ice for ninety men. One three-hundred-plus tackle lost seven pounds and had to receive IV fluids.

The Archives  article and a subsequent Harvard Heart Letter detailed research and historical perspective. Our intake of sodium, in table salt and foods, is important, but the ratio of how much sodium to potassium in our diets may be even more crucial.

An older edition of the Harvard Heart Letter compared our modern diet to that of our primitive ancestors. Paleolithic man consumed sixteen times as much potassium (in milligrams) as sodium; today our typical diet has nearly five times as much sodium and less than a quarter of the potassium as the hunter-gatherers ate, so the ratio has marked changed.

lots of potassium in this bunch

So how do you return to a healthier diet, in those terms. Well, a banana, for instance has over 400 milligrams of potassium and almost no sodium (1 milligram). An orange has over 230 times as much potassium as sodium, steamed Brussels sprouts 35 times as much (I mean in milligrams in all cases, so scientifically my comparisons are ratios).

The Texan's head dietician and senior trainer are altering the team's diet, using lots (and I mean lots) of electrolyte-containing vegetables and fluids. They even formed a players' food committee to make sure the team members would have choices that they would like. Southerners want okra and potatoes, so that's what they get. The team members were concerned about blood pressure effects from all the salt they're getting; then they heard how the new research showed foods high in potassium and other electrolytes can balance out the effects of sodium.

The proof is in the pudding is the old saying; we'll see how the Houston team does when the season starts.

But I can certainly see the sense behind their approach.

 

Hypertension: some good news

Tuesday, May 31st, 2011

Let's check your BP

I was reading a blog post from May 2010 written by an unidentified cardiologist. Some of the underlying issues were worth following to better sources. The blog stated that high blood pressure is our most common chronic disease. It went on to mention the connection between BP and weight, saying, as a nation, America is one million tons overweight. It claimed that ten pounds of weight loss could normalize the BP of many Americans.

I initially got into today's data search because of a Wall Street Journal article (Personal Journal; May 31, 2010; pp.D1-2) titled "A Long-Awaited Advance in the War on Blood Pressure." I Googled the author, Ron Winslow and he is the deputy editor for health and science and a senior medical and health care writer for WSJ with over a thousand articles written.

He reported that the American Society for Hypertension (ASH) met in New York last week (May 21-24,2011) and Dr. Brent Eagan, the vice president of ASH, and Professor of Medicine at the University of South Carolina reported some real progress on the multi-state Hypertension Initiative he heads. It's working with ~500 primary care practitioners and over 110,000 hypertensive patients in the Southeast. Nearly 70% of their patient have controlled BPs now (vs. 40% a decade ago).

About as far away as you can get in the U.S., Kaiser Permanente's northern California branch follows >600,000 patients with hypertension and reported at the same ASH meeting that 80% of that group have controlled BP readings compared to 44% ten years back.

One of the Kaiser patients had a regular checkup in 2007 and had mildly elevated BPs then (145/74). Her own comment was, "Here in northern California, we believe in exercise and good nutrition and we're not into pills."

Yet her doctors started her on two medications for hypertension and early this year her BP was 117/74. She's walking three miles three times a week, eating fruits and vegetables and going to a strength-training class at a gym. I don't know if she lost weight also, but I wouldn't be surprised. I mentioned in an earlier post, that my own BP fell markedly after I lost ~25 pounds, and the dosage of the anti-hypertensive drug I've been on for years had to be cut in half.

Guess who's at higher risk for CV disease

So why am I writing about this in a blog devoted mostly to weight/diet/exercise?  First, there's an increased awareness of the association between excess weight, high BP and cardiovascular risk at all ages. An article in the Feb 3, 2009 edition of Circulation looked at the issue in children and adolescents. Concentrating on the Metabolic Syndrome (obesity, diabetes, hypertension, abnormal blood lipids), there was, even in these young people, a definite correlation between the degree of obesity and cardiovascular risk. They stated that strong evidence places obesity as the most significant risk factor

Can I tie all this together? Well I'd say bluntly that obesity is our major enemy, it's a major causal factor in hypertension which is being treated pharmacologically at earlier stages and that diet and exercise are extremely useful ways to combat both entities.