Tag Archives: Blood Pressure

Does Hypertension Put You at a Higher Risk for Infection or Death From Covid-19?

Early news reports of fatalities in China from coronavirus strongly implied that hypertension was an independent risk factor for severe disease and death.

Bloomberg and many other seemingly reliable news sources relied on one Chinese doctor’s anecdotal statements along with a Lancet article to make this claim:

“A top Chinese intensive care doctor told Bloomberg that of 170 patients who died in January in Wuhan, nearly half had hypertension, and anecdotally he said that he and other doctors have noticed hypertension is prevalent in those who die.”

However the actual Lancet report on 191 patients published March 11, 2020 , entitled Clinical course and risk factors for mortality of adult inpatients with COVID-19 in Wuhan, China: a retrospective cohort study did not find hypertension or heart disease to be an independent risk factor for severe respiratory disease or death.

Of the 191 patients, 137 were discharged and 54 died in hospital. 91 (48%) patients had a comorbidity, with hypertension being the most common (58 [30%] patients), followed by diabetes (36 [19%] patients) and coronary heart disease (15 [8%] patients).

Although patients with hypertension were more likely to die than those without hypertension this does not prove hypertension is an independent risk factor

Age was by far the most significant risk  factor and the older patients also had more hypertension. When all variables were factored into an analysis, hypertension and heart disease were not significantly related to death:

Multivariable regression showed increasing odds of in-hospital death associated with older age (odds ratio 1·10, 95% CI 1·03–1·17, per year increase; p=0·0043), higher Sequential Organ Failure Assessment (SOFA) score (5·65, 2·61–12·23; p<0·0001), and d-dimer greater than 1 μg/mL (18·42, 2·64–128·55; p=0·0033) on admission

Heart disease and hypertension were not significant factors after accounting for age.

Nephrology Journal Club (NephJC) has an excellent discussion (frequently updated and well-reference)  on this topic here. After looking at all current publications in this area they agree with me that the current data do not support the idea that hypertension is an independent risk factor for either getting SARS-CoV2 or having a more serious illness from it.

Among the patients with COVID-19, it seems the prevalence of prior h/o HT is higher in those who develop severe disease than those who do not. Same applies for development of ARDS or death – but mostly in unadjusted analysis. See table below for more. The last two rows are the best quality data so far, and suggest the association between COVID-19 severity and hypertension is attenuated after adjustment.

updated HT table.JPG

Sources: Guan et al, NEJM; Huang et al, Lancet; Wang et al, JAMA; Zhang et al, Allergy; Zhou et al, Lancet; Wu et al, JAMA IM; Italian report (PDF); Chen et al, BMJ; Shi et al, JAMA Cardiol; McMichael et al, NEJM; Guo et al, JAMA Cardiol; Bean et al, MedRxiv 2020; Petrilli et al, MedRXiv 2020

As can be seen, most of the studies except the last two, did not adjust for age. Even age-stratified association of hypertension would have been a more useful way to see these data to understand this issue a bit better. We hope more data in coming days will clarify this relationship. Unlike what we stated earlier, the Zhou et al study did not adjust for hypertension.

Source: AHA website , using NHANES data

Source: AHA website, using NHANES data

As can be seen above, hypertension in the general population closely associates with increasing age, hence any association with hypertension may merely represent confounding due to age, and should be interpreted after careful analysis.

The Question Is Definitively Answered

The speed at which data and studies are being published on Covid-19 is so rapid that a study has been published since I began writing this post which I feel definitively answers my title question.
Using observational data on 8910 hospitalized patients in 169 hospitals in Asia, Europe, and North America, investigators examined cardiovascular factors that were associated with in-hospital death.
Surprisingly, in this database, although the average age of the 515 nonsurvivors was 56 years versus 49 years for the 8195 survivors, there was no difference in the prevalence of hypertension. In fact survivors had a slightly higher prevalence of hypertension (26.4% versus 25.2%) despite being younger than the nonsurvivors.
A multivariable logistic-regression model identified age>65 years, coronary artery disease, heart failure, arrhythmia, COPD and current smoking as independently associated with in-hospital death.
nejmoa2007621_f1
Hypertension was not independently associated with in-hospital death.
Interestingly, patients receiving ACE inhibitors and statins were substantially less likely to die.
In Summary
  1. Hypertension does not put you at a higher risk of serious illness or death due to Covid-19.
  2. As discussed in previous posts (see here and here), there is no reason to stop taking your ACE inhibitor or angiotensin receptor blocker (ARB) blood pressure medication during this pandemic. (Also don’t start demanding you be put on an ACE inhibitor-the protective association seen in one study does not prove causality, we need randomized trials to show drugs safety and effectiveness!)
  3. Be very skeptical of early anecdotal reports and small trials rushed to publication (especially “preprints” which have not been peer-reviewed) during Covid-19. The poorly substantiated claims that hypertension was a major risk factor for death and that ACE inhibitors increased patient’s risk during Covid-19 have proven false. As better data emerges regarding hydroxychloroquine, despite enthusiastic anecdotal reports from some physicians, this drug has not been proven safe and/or effective for Covid-19 treatment.

Skeptically Yours,

-ACP

 

Why I Encourage Self-Monitoring Of Blood Pressure In My Patients With High Blood Pressure

The skeptical cardiologist primarily makes decisions on blood pressure treatment these days based on patient self-monitoring. If high readings are obtained in the office I instruct patients to use an automatic BP cuff at home and make a measurement when they first get up and again 12 hours later. After two weeks they report the values to me.

I described in detail the recommended technique in my 2018 post entitled “Optimal Home Blood Pressure Monitoring: Must The Legs Be Uncrossed and The Feet Flat?

Although I’ve been recommending self-monitoring to my patients for decades it is only recently that guidelines have endorsed the approach and good scientific studies verified its superiority. I was pleased when the 2017 ACC/AHA guidelines for High Blood Pressure made home self-monitoring of BP a IA recommendation.

And last year a very good study, the TASMNH4 was published which demonstrated the superiority of self-monitoring compared to usual care.

TASMINH4 was a parallel randomised controlled trial done in 142 general practices in the UK, and included hypertensive patients older than 35 years, with blood pressure higher than 140/90 mm Hg, who were willing to self-monitor their blood pressure. Patients were randomly assigned (1:1:1) to self-monitoring blood pressure (self-montoring group), to self-monitoring blood pressure with telemonitoring (telemonitoring group), or to usual care (clinic blood pressure; usual care group).

The home BP goal was 135/85 mm Hg, 5 mm Hg lower than the office BP goal. At one year both home self-monitoring groups had significantly lower systolic blood pressure than the usual care group.

This trial was not powered to detect cardiovascular outcomes, but the differences between the interventions and control in systolic blood pressure would be expected to result in around a 20% reduction in stroke risk and 10% reduction in coronary heart disease risk. Although not significantly different from each other at 12 months, blood pressure in the group using telemonitoring for medication titration became lower more quickly (at 6 months) than those self-monitoring alone, an effect which is likely to further reduce cardiovascular events and might improve longer term control.

Advantages of Home Self-Monitored Blood Pressure-Limitations of Office BPs

I described why I switched to home BPs in a post about the landmark  SPRINT trial in 2015:

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.

In addition, I feel that multiple assessments of out of office BP over the course of the day and different days are more likely representative of the BP that we are consistently exposed to rather than one reading in the doctor’s office.

Accuracy and technique in the doctor’s office is also an issue.

Interestingly, we have assumed that manual office BP measurement is superior to automatic but this recent paper found the opposite:

Automated office blood pressure readings, only when recorded properly with the patient sitting alone in a quiet place, are more accurate than office BP readings in routine clinical practice and are similar to awake ambulatory BP readings, with mean AOBP being devoid of any white coat effect.

A patient left a comment to that paper which is quite insightful:

I had a high blood pressure event several years ago. Since then I have monitored my BP at home, sitting with both feet flat on the floor, not eating or drinking, not speaking or moving around, on a chair with a back, and without clothes on the arm being used for the measure. My BP remains normal.

I have never had my BP taken correctly in a doctor’s office. They will do it while I am speaking with the doctor, sitting on an exam table with my legs swinging, with the monitor band over my heavy winter sweater, right after I have sat down. They do not ensure that my arm is supported or at the right height. If I recommend that I take off my sweater, or move to a chair with a back, they tell me that is not needed. I have decided to refuse such measurements. How can they possibly be monitoring my health this way?

This patient’s observations are not unique and I suspect the majority of office BPs have most if not all of the limitations she describes.

Self Monitoring Improves Patient Engagement In BP Control

I have found self-monitoring of patient’s BP to substantially enhance patient engagement in the process. Self-monitoring patients are more empowered to understand the lifestyle factors which influence their BP and make positive changes.

Blood pressures are amazingly dynamic and as patient’s gain understanding of what influences their BP they are going to be able to take control of it.

I take my BP almost daily and adjust my BP medications based on the readings. After prolonged work or exercise in heat, for example, BPs will decline to a point where I’m light headed or fatigued. Less BP med at this time is indicated. Conversely, if I’ve been overly stressed BPs increase and upward titration of medication is warranted.

With some of my most engaged and enlightened patients we perform similar titrations depending on their circumstances. Sometimes patients perform these titrations on their own and tell me about them at the next office visit.

What’s The Best Way To Communicate Home BPs?

Many of my patients provide me with a hand-written record of their BPs over two weeks.  Some mail them to me, others bring them in to the office. We scan these into the EMR. I look at these and make an estimate of the average systolic blood pressure, the variation over time and the variation during the day. It’s not feasible for me or my staff to enter the numbers or precisely obtain an average.

Some patients send us the numbers through the internet-based patient portal into the EMR. This is preferable as I can view these and respond quickly and directly back to the patient with recommendations.

More and more patients are utilizing their smart phones to record and aggregate their health data and will bring them in for me to look at during an office visit. I’ve described one stylish and slick BP cuff, the QardioArm which has neither tubes nor wires and works through a smartphone app. Omron , also has multiple cuffs which communicate via BlueTooth to store data in a smartphone app.

Ideally, we would have a way for me to view those digitally recorded BPs with nicely calculated averages online and within the EMR. Unfortunately, such connectivity is not routinely available.

However, for my patients who are already monitoring their heart rhythms with a Kardia mobile ECG and are connected with me online through KardiaPro Remote I can view their BP recordings online.

I’ll discuss in detail in a subsequent post the Omron Evolv home automatic BP cuff (my current favorite) which is wireless and tubeless and connects seamlessly to KardiaPro allowing me to view both BP and heart rhythm (and weight) recordings in my patients

To me, this empowerment of patients to record, monitor and respond to their own physiologic parameters is the future of medicine.

Sphygmomanometrically Yours,

-ACP

From the 2017 ACC/AHA BP guidelines

and the proper technique for office BP measurement

 

 

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