Tag Archives: Blood Pressure

Salt Talks Two

The skeptical cardiologist found himself reading a cookbook the other day, something he heretofore had avoided. Cookbooks somehow seem archaic and, I presumed, exclusively the domain of the women in my life.  My mother had loads of them, hiding their food-stained bindings behind a cabinet door in my childhood kitchen. Whereas I can stare longingly at all manner of books on  bookstore shelves, I scrupulously avoid the cooking section, finding nothing that intrigues or attracts me in their heavily illustrated contents.

The eternal fiancee’ of the skeptical cardiologist (EFOSC), I believe, had requested I find the recipes for several dishes we (more accurately, she) could prepare the next week and had headed off to Whole Foods or Nordstrom Rack or Pier 1 (all of which, strangely and conveniently sit side by side).

IMG_6880 copyAfter receiving directions on where these mysterious tomes resided, I grabbed the cookbook that looked the most interesting: Ruhlman’s TWENTY: 20 Techniques, 100 Recipes, A Cook’s Manifesto. Instead of searching for recipes I ended up being distracted by Chapter 2: Salt: Your Most Important Tool.

In Chapter 2, Ruhlman makes the bold statement that “if you don’t have a preexisting problem with high blood pressure and if you eat natural foods-foods that aren’t heavily processed-you can salt your food to whatever level tastes good to you without worrying about health concerns.”

As I’ve written previously, I agree with him, and a recent article published in The Lancet casts further doubt on recommendations for the general population to limit sodium consumption drastically.

In the Lancet article, the authors did a pooled analysis of four large prospective studies involving 133118 patients in 49 countries. They studied the relationship between salt consumption, measured by 24 hour urine excretion of sodium (because what goes in must come out) and the incidence of cardiovascular disease and death over about 4 years.

The findings:

  1. Patients without hypertension who excreted more than 7 grams/day of sodium were no more likely to have cardiovascular disease or death than those excreting  4-5 grams/day.
  2. In fact, in both normotensive and hypertensive groups, sodium excretion of < 3 g/day was associated with a significantly (26% higher in normotensives, 34% in hypertensives) increased risk of cardiovascular disease and death.
  3. The only group that would appear to benefit from lower sodium consumption was the hypertensive group which excreted 7 g/day of sodium and when compared to the hypertensive group that excreted 4-5 g/day of sodium had a 23% higher risk of CV death and disease.

If we have to worry about anything with salt consumption, this study (and others) suggests that it is consuming too little salt.

The only group that need worry about too much salt consumption is those who have hypertension and who consume a really large amount of salt.  Since the average American Average consumes 3.4 grams per day of salt, very few of us are consuming over 7 g/day.  Despite this, The American Heart Association continues to stick by its totally unjustified recommendation that sodium levels be no higher than 1,500 mg/day, and other organizations recommend sodium levels below 2,300 mg/day.

What Kind of Salt Should We Consume

Ruhlman recommends coarse kosher salt, preferably Diamond Crystal or, if that’s not available, Morton’s.

Why? Because “salt is best measured with your fingers and eyes, not with measuring spoons.”

“Coarse salt is easier to hold and easier to control than fine salt.”

He feels that salting is an inexact skill and one should always salt to taste.

“When  recipe includes a precise measure of salt, a teaspoon, say, this is only a general reference, or an order of magnitude–a teaspoon, not a tablespoon. You may need to add more. How do you know? Taste the food.”

IMG_6874
The skeptical cardiologist’s frittata.

These words were music to my ears as I am an advocate of serendipity, chaos and creativeness in the kitchen.  When I make a frittata, as I did this morning, I measure nothing precisely; not the butter and olive oil used to sauté, the bell peppers, onions and garlic; not the milk mixed with the eggs; not the cheese sprinkled on top; not the time spent in the oven or even the heat; and most assuredly, not the salt and pepper.

IMG_6876At the end of the frittata creation process I took a bite. It was delicious but it needed something: a touch more salt. I sprinkled some David’s kosher salt on top and tried again, Perfection!

Although I have hypertension, I know (see discussion here) that my salt consumption is way below 7 grams/day and, if anything, based on the most recent studies, I should be worrying about too little sodium in my diet.

saltatorily yours,

-ACP

PS>

As I outlined in one of my previous posts on salt, here is what I tell my patients:

  • Spend a day or two accurately tracking your consumption of salt to educate yourself. I found this app to be really helpful. I’ll expand on this in a future post.
  • Recognize that not everybody needs to follow a low salt diet. If your blood pressure is not elevated and you have no heart failure you don’t need to change your salt consumption.
  • If your blood pressure is on the low side and especially if you get periodic dizzy spells, often associated with standing quickly liberalize your salt intake, you will feel better.
  • If you have high blood pressure, you are the best judge of how salt effects your blood pressure. In the example I gave in a previous post, my patient realized that all the salt he was sprinkling on his tomatoes was the major factor causing his blood pressure to spike.
  • The kidneys do a great job of balancing sodium intake and sodium excretion if they are working normally. If you have kidney dysfunction you will  be more sensitive to the effects of salt consumption on your blood pressure and fluid retention.
  • If you are following a Mediterranean diet with plenty of fresh fruits and vegetables you are going to be in the ideal range for both potassium and sodium consumption.

Home Versus Office Blood Pressure and the “Landmark” NIH Blood Pressure Trial

The NIH yesterday announced that they had prematurely ended a large trial looking at outcomes when hypertensive patients (aged >50 years) were treated to lower versus higher blood pressure goals.

The data showing a benefit in those treated to the lower goal were apparently so compelling the scientists tasked with monitoring them felt they needed to be published as soon as possible.

According to the NIH press release

“the intervention in this trial, which carefully adjusts the amount or type of blood pressure medication to achieve a target systolic pressure of 120 millimeters of mercury (mm Hg), reduced rates of cardiovascular events, such as heart attack and heart failure, as well as stroke, by almost a third and the risk of death by almost a quarter, as compared to the target systolic pressure of 140 mm Hg”

These data won’t be published for several months but if they hold up under close scientific scrutiny it will change the way I and other physicians treat hypertension dramatically.

The lower BP goal patients in this study were on three BP meds versus two for the higher goal. To achieve a goal of 120 mm Hg I think it is highly likely that I will have to add an additional BP med to all of my patients.

With more stringent BP goals it will become crucial to make sure that we are getting accurate BP data on our patients. But what kind of BP data should we be looking at and what technique for obtaining the BP should be employed?

Home Versus Office Blood Pressure

Every patient I see in my office gets a BP check. This is typically done by one of the office assistants who is “rooming” the patient using the classic method with , listening with stethoscope for Korotkov sounds. If the BP seems unexpectedly high or low I will recheck it myself.

Often the BP we record is significantly higher than what the patient has been getting at home or at other physician offices.

There are multiple factors that could be raising the office BP: mental stress from driving to the doctor or being hurried or physical stress from walking from the parking lot.

Conscious or subconscious anxiety about what the doctor may find is thought to  play a role, so-called “white coat” effects.

Consequently I rely more on home BP monitoring when making decisions on treatment initiation or change

bpcuff
The skeptical cardiologist’s home BP cuff. Note the early AM systolic BP which is acceptable under current BP guidelines but would be unacceptable if goal becomes <120 mm Hg. Also note that music is about to be played which will lower BP. There are 3 directions in the graphic. 1. Position cuff 0.8-1.2″ above elbow 2. Center tuber over middle of arm 3. Allow room for two fingers to fit between the cuff and your arm.

Accurate automatic BP devices can be purchased from Walgreen’s or CVS for around $40.

I recommend devices that have a cuff that goes around the upper arm and have as few frills as possible.

I usually ask patients to take a BP in the morning and evening daily for two weeks and report the values to me.

The SPRINT study likely, however, used in office BP measurements and followed the BP taking recommendations on their website as follows:

  • Don’t drink coffee or smoke cigarettes for 30 minutes prior to the test.
  • Go to the bathroom before the test.
  • Sit for 5 minutes before the test.

The Harvard Health website adds even more requirements for taking BP

  • Avoid caffeinated or alcoholic beverages, and don’t smoke, during the 30 minutes before the test.
  • Sit quietly for five minutes with your back supported and feet on the floor.
  • When making the measurement, support your arm so your elbow is at the level of your heart.
  • Push your sleeves out of the way and wrap the cuff over bare skin.
  • Measure your blood pressure according to the machine’s instructions. Leave the deflated cuff in place, wait a minute, then take a second reading. If the readings are close, average them. If not, repeat again and average the three readings.
  • Don’t be too concerned if a reading is high. Relax for a few minutes and try again.

What is the True Blood Pressure?

It seems to me that the most important thing in blood pressure control is what the blood pressure is the majority of the time. Consequently I have always questioned the advice to throw out high readings and to only utilize BP measurements obtained after sitting quietly for 5 minutes.

After all, if you are active most of the day as you should be, it would be rare for you to be sitting quietly doing nothing for 5 minutes. The BP  you first take, although higher than one 5 minutes later, might be a more accurate reflection of your average BP during the day.

Most days you are exposed to a variety of stressors related to work or personal and family situations and your BP is likely reacting to these stressors. The “sitting quietly for 5 minutes” BP is not reflective of these higher readings.

In addition, if you only take your BP when your bladder has just been emptied and you have not had any caffeine it is likely an underestimate of the average daily BP which includes full bladders and cups of coffee.

For these reasons I only tell my patients to take the BP twice a day. I don’t instruct them to sit quietly or throw out the high readings or avoid caffeine. I want BPSs that truly represent the normal daily fluctuations. I don’t want to cherry pick “good” BPs.

I am eagerly awaiting the publication of the SPRINT data which may alter BP treatment dramatically.

Until then I’m sticking to the guidelines published two years ago (and which I wrote about here) which aimed for SBP <140 mm Hg for patients less than 60 years and <150 mm Hg for those older than 60.

diastolically yours

-ACP