Let's start by asking the question, "Who should have the capability of checking the blood pressure at home?" The simple answer is everyone, although yes, I will agree that some need it more than others.

          Why everyone? A few simple facts will help make this clear. High blood pressure, or what we call hypertension, is exceedingly common. The prevalence increases with each decade of life, so that if we look only at people age 60 or greater, the majority have high blood pressure.

          High blood pressure, especially if it is undetected and untreated, is clearly dangerous and significantly increases the chance of a heart attack, or stroke, or kidney failure in the years to come.

          Most people who have hypertension have no symptoms. Simply said, if you wait until you "feel something", you will be postponing what could be lifesaving treatment. Not a good idea.

          The average person going in to their primary care doctor's office or a Cardiologist's office will be found to have high blood pressure. Usually just the idea of going in starts to raise the blood pressure. Then the drive in, trying to arrive early or on time, sitting next to strangers in the waiting room, being rushed back into the room by the medical assistant, being told to "hop up" on the table, stay still and before you know it, out comes the elevated blood pressure reading. It's no wonder. A component of what we call "white coat hypertension" is very common, even if your provider is not wearing a white coat. Even people who come right out and announce that they are not nervous often have some degree of this.

          By being able to calmly check the BP (abbreviation for blood pressure) in the comfort of your home takes away most of these factors. You just have to know how to do it properly. It's really fairly simple, but there are some basic rules to follow.

          Before we get into the specifics, we should tackle a few concepts. First and foremost, BP is not a fixed or static number. It changes moment to moment throughout each day. Therefore, no one will have perfect BP numbers 100% of the time. I have always stressed to patients that the best approach is to look at the overall trend or average. Everyone has and is entitled to both good days and bad days. We all do. In order to look at the overall picture, you have to overlook some of the high readings, and some of the low readings and focus more on the big picture.

          I have had many patients try to "micro-manage" their BP on their own, taking an extra half pill some days, then dropping the dose of one of the BP medications another day. This is never a beneficial or useful plan and I would strongly advise against this. The cardiovascular system prefers consistency. If anything, too much data tends to make most people just worry more, and this then leads to checking the BP again, and again. I've actually been called during the night, through the answering service emergency line, from a patient declaring that the "ninth blood pressure reading was really high." I can't help but ask the patient, tactfully of course, why they checked the blood pressure 9 times, during the night ?

          Most blood pressure medications take a few days to kick in, when the dose is increased, sometimes longer. Intentionally skipping a dose, when the pressure is low, will lead to the blood pressure coming up over the next couple of days. The rise does not occur within hours. The end result will be more fluctuations of up and down. It is always better to be consistent, and if you are seeing a fair number of readings that seem to be too low (the top or systolic number hovering around 100 or less), or the numbers are running high (the systolic top number over 140 or diastolic over 90), then it might be time to reach out to your provider, let them know, and work with them to see if you would benefit from a lower or higher dose of medication. Most doctors do not like their patients adjusting medication doses without the doctor's input. 

          So how often should the blood pressure be checked? It depends on the person's history. If the patient is fairly young, has not been diagnosed with hypertension, is not taking any BP medication, maybe they are overweight or have a family history of high blood pressure, checking the BP once per month,  or even a few times per year is enough. If the person has been on BP medication using a stable regimen (no recent dose changes, same medications), then 1-2 times per week is likely sufficient.  If the person just started a new BP medication, or the dose was recently increased, or the BP was found to be quite abnormal at a recent doctor or ER visit, checking 1-3 times per day would be advisable.

          I usually recommend that the BP be checked at varying times of day, not the same time each day. This can help give a more accurate representation of the true readings. The average person's blood pressure rises from early morning peaking in mid-day, and is lower in the evening. But there are lots of exceptions, particularly in people who might be taking a medication that is starting to wear off.

          This next point is a critical one. The blood pressure is meant to be checked on a normal day, although some patients tell me that they never have a normal day. The important point here is that if your are having a really stressful day, you can bet that the BP will be high. I see little or no reason to check it that day. Time and time again, I hear about someone having a confrontation with a co-worker, or a fender bender driving home, or an argument with their spouse or partner. They then reach for the BP machine, find the reading to be inordinately high, and they then assume that the stressful situation has "affected my heart." That's usually not the case. The elevated reading is to be expected, does not translate into needing a stronger BP medication, and only adds to the already difficult day. In this situation, it is almost always better to do something healthy to unwind, perhaps a relaxing walk or some other gentle exercise, yoga, meditation, or something along those lines. Then recheck the BP after the stress has settled down.

          Just a few more details before we hit the actual protocol. Best to not drink a large caffeinated beverage (like coffee), or smoke a cigarette or cigar or vape, the 30 minutes prior to taking the blood pressure.  Also best to avoid exercise (you won't hear that one often from a Cardiologist) and avoid eating during the 30 minutes prior to the BP check. In other words, don't have your breakfast, 2 cups of coffee, then sit and check it. Do it on an empty stomach, before breakfast, or mid-afternoon, or before bed.

         We can now proceed with the proper protocol itself. I will split this into 3 parts:  the equipment, the method, and the results.

          The equipment issues, in my opinion, are fairly straightforward. For most patients, the best option is an electronic battery powered arm cuff. They are fairly accurate, they are easy to use, and are relatively inexpensive. Although a medical grade cuff with a stethoscope may be more accurate, it is not usually feasible to do alone on yourself. So if you happen to have a medical person at home (such as a nurse or medical assistant), that might be a good choice. I am also not a fan of wrist cuffs. I find them to generally be less accurate than arm for the average patient.

          A number of smartwatches do offer the ability to measure blood pressure. But once again, they are not accurate enough at this point to endorse their use. They are accurate at detecting heart rate, but not for BP.

          For most people, an arm cuff (the part that wraps around the arm) with the "standard or regular" size will be most appropriate. This works well for 8 out of 10 people. In theory, the size of the cuff should be matched to the size of the person's arm. If the arm circumference (the distance around the outer surface) at the level of the mid biceps area is considerably larger than the cuff's recommended range, using it could cause the cuff to "pop open" as it is inflated. It may also give a falsely elevated reading. If the cuff is too large for the arm, it could yield a falsely low BP reading.

          If your arm is fairly average in size, most people can just buy a standard cuff. If in doubt, find a cloth tape measure and measure the arm circumference. You can buy one online for less than 5 dollars (and you can also use it to measure your "waist circumference" for one of my other lessons). Use the arm circumference ranges below for reference:

• Small cuff:  22-26 cm arm circumference (roughly less than 10 inches)

• Standard adult:  27-34 cm (10-13 inches)

• Large arm cuff:  35-44 cm (14-17 inches)

• Extra large arm cuff:  45-52 cm (18 inches or greater)

Yes you can purchase a larger arm cuff for some BP machines, but usually the one in the box at the store will be a standard cuff, unless otherwise specified. If you buy the cuff separately, make sure it is "compatible" and can be plugged into your machine.

          I try not to recommend a specific brand of machine to patients. I do tell people that a basic model, usually found online or at most pharmacies or grocery stores for around 40-60 dollars is adequate. There is usually no reason to purchase a $150 dollar one that has fancy dials and alerts. Go with the basics. I also recommend keeping the receipt for at least 30 days. If possible, have it "checked" by bringing it in to your doctor's appointment and have the medical assistant check the blood pressure, then using the same arm just a few minutes later, recheck it with your new machine. If it is off by more than 10-15 points, I would consider returning it. 

          It is best to keep the BP machine out, and in the same place, for those that are checking BP on a regular basis. If you have to go searching for it in the pantry or closet, the chances are you won't use it. It is better at the kitchen table than in bed or on the sofa. The arm position will need to be "level" with the heart, and this is much easier if sitting in a chair at a table.

          Once you are ready, sit in the chair at the table, with a back supported chair, both feet flat on the ground, not crossed. I advise people to then sit quietly, without talking, or watching the news, or texting, or speaking. This should be done for at least 5-10 minutes. I always find it fascinating how many people immediately state that they believe it will be really difficult to sit quietly for that long of a period of time. How interesting. Best to concentrate on quiet slow and steady breathing. Eyes can be open or closed, but the goal is to find that inner peace type of feeling.

          Then, place the arm in front of you, on the table, palm up, with the arm totally relaxed or flaccid. Slide the cuff up to mid upper arm level with the bottom of the cuff just above the "crease." The cuff usually has Velcro, and it should be tight enough at baseline that it will stay in place when pulled "up", but loose enough that it can be "pulled off" without much difficulty. Adjust the Velcro tension to do this. Most have a small arrow or marker that is to be placed over the artery, basically between the inner and outer part of the elbow, on the top (front) surface. The artery is slightly more toward the inner elbow, if you want to be accurate. Push the inflate button, and let it do it's thing. Try not to tense up, as the cuff inflates and deflates. Then, after it is done, the numbers are displayed. All machines offer the 2 blood pressure numbers (the systolic and the diastolic) and the pulse rate.

          The top BP number is called the systolic, and this occurs as the heart pumps. The lower BP number is called the diastolic, and is present when the heart relaxes. Both are important and should be recorded into a legible "log" book or on paper along with the heart rate. Try to also document the date, and the time of day. Some experts recommend doing a second reading, 3-5 minutes after the first one, and then averaging the two. This is not a bad idea, but I would not consider it a requirement. For those who are prone to being anxious when checking it even at home, this may be prudent. I always like to see a legible "list" on paper, as a provider. Some patients like taking a "photo" of the display. I find this less useful, and cumbersome. Yes, many of the machines have a memory where the user can "skim through" the display readings. Again, I think a single page log of the readings, with date, time and the 3 numbers, is ideal. I can usually tell an engineer, from a distance. Not only do they have the log of the numbers, but they frequently plotted the numbers on a curve, using a graph, and calculated the mean (average) readings on a weekly basis. You don't really have to do this.

          I am often asked, "OK, now I have the numbers, what am I supposed to do with them?" The log can then be brought into the doctor's office at the time of your next visit, to be viewed by the provider and evaluated and discussed. Alternatively, if you use an electronic communication portal with your provider, you could either scan the results over, or type them out to send. If the numbers seem to be in range, it might be OK to keep them for a couple of months, before presenting them to your provider at the office visit. If the readings are severely out of range, either direction, then best to bring it to their attention much sooner.

         What do the numbers mean? Where should the numbers be? For years now, there has been a consensus on this. Several years ago, there was a national consensus opinion (from the top blood pressure experts in the country) that in the elderly, it was acceptable to let the systolic top BP number run higher, even up to 150. Although this was included in the national guidelines for providers to follow, the end result was a greater than expected rise in heart disease and mortality or death by allowing the number to be higher. Now, the same recommendations apply to all patients, regardless of age. So the current standard recommendations and definitions are listed below. Make sure you pay attention to the ANDs and the ORs.

Normal BP:  Systolic less than 120 mm Hg AND diastolic less than 80 mm Hg

Elevated BP:  Systolic 120-129 AND diastolic less than 80 mm Hg

Stage 1 hypertension: Systolic 130-139 mm Hg OR diastolic 80-89 mm Hg

Stage 2 hypertension:  Systolic greater than 140 mm Hg systolic OR diastolic greater than 90 mm Hg

In general, hypertension should be diagnosed based on at least 2 separate readings, carefully performed, on at least 2 occasions. Remember that "everyone can have a bad day" thing?

          The numbers above are for "defining" the groups. The actual goal of treating hypertension varies depending on the person's medical and cardiac conditions. It has been proven, in very large numbers of solid research studies, that treating hypertension helps reduce the risk of future heart attack, heart failure, cardiovascular death, stroke, dementia, kidney failure, and many other life threatening illnesses.

          How is hypertension treated? A substantial part of the treatment is in the hands of the patient. In someone who is overweight or obese, losing weight often has a large impact on blood pressure. Maintaining a regular and consistent exercise or physical activity program often helps lower blood pressure. Eating a low salt diet, avoiding alcoholic beverages, avoiding cigarette smoking or vaping, staying away from nonsteroidal anti-inflammatory drugs, diagnosing and treating sleep apnea, and developing healthy methods of stress relief can all help. Following this list may not cure you of hypertension, but it can have a large beneficial effect, and can often lead to either less medication or lower doses. 

          The mainstay of treatment for most patients with hypertension will be prescription medications. I know this makes many people cringe, but again when one looks at the benefits and the risks, the benefits of treating hypertension far outweigh the potential risks of the drugs. There is no debate on this. Unfortunately, the average patient with hypertension that is on prescription medication needs an average of two or more blood pressure medications daily, in order to achieve adequate control. The good news here is that there are now some wonderful blood pressure medications available to prescribe, with low risks of worrisome side effects.

         Who needs to be treated? This is where it gets a little tricky. In patients who have clinical cardiovascular disease, such as a prior heart attack, or stent, or bypass surgery, or heart failure, medications should be initiated to keep the systolic under 130 and the diastolic under 80. In patients without clinical cardiovascular disease, there are 3 additional factors that go into the formula and decision making. If the person is a diabetic, or the person has chronic kidney disease (kidney failure), or the person's estimated 10-year calculated risk of a cardiac event (I have a chapter on risk assessment tools, specifically the PREVENT tool) is at 7.5% or greater, medications should be initiated to keep the systolic BP under 130 and the diastolic under 80, and in many of these patients, we like to see the numbers even lower, with systolics under 120.

          If the person has no clinical cardiovascular disease, no diabetes, no chronic kidney disease, and their 10 year calculated risk is under 7.5%, then a 3-6 month trial of "lifestyle changes" is usually considered appropriate as a first step. That person would need to really work hard on diet, exercise, and the other choices I described. If the blood pressure does not improve, then medication would need to be started.

          Once again, the decisions on when to start treatment, what drugs to use, and where the BP should be kept are best left to a personalized discussion with your primary care person, or your Cardiologist if you have one. A skilled provider, knowing your blood pressure numbers, your cardiac history, your A1c level, your kidney function numbers and your 10 year calculated risk, will be able to offer you the best advice for you. At least now, you can go into the discussion armed with the proper tools to be an active participant in the discussion.    

           So to summarize the key points, best to have the proper equipment at home and know how to use it. Try not to overdo the BP checks. An appropriately fitted arm cuff is best. It is critical to sit and really relax before each reading and follow the proper protocol. Then record the numbers in a legible fashion to be reviewed later by your provider. Once the data is available for review, then a treatment plan can be made that is best for you. But realize, you don't need your doctor's approval to start working on heart healthy habits (and avoiding bad ones). You don't even have to memorize the blood pressure charts listed above. Even if you don't officially have hypertension, a heart healthy lifestyle can help "prevent" hypertension. The best time to start is now.