In Depth 7-Day Home Blood Pressure Monitoring Guide

High blood pressure shouldn’t be ignored, even if it’s just a one-off high reading. Untreated hypertension can cause slow internal damage, leading to serious health conditions. If you suspect that your blood pressure is abnormal, you should consider doing 7-day Home Blood Pressure Monitoring. This will provide you with an average reading, giving you greater insight into your blood pressure and whether you need to be concerned. 

You can view our previous blog “What is 7-Day Home Blood Pressure Monitoring?”, to find out what it is and why we should do it.  

 Follow the below steps every day for at least 4, but ideally 7 days in a row:

• Check your blood pressure twice daily, in the morning and the evening.
• When you check it, ensure you sit quietly and still for 3 minutes prior.
• After the first check, write your reading down (or enter it on mybloodpressure.co.uk), sit quietly and still for at least another 60 seconds, then check it a second time.
• At the end of the 7 days, ignore the readings from the first day and work out separate averages for the top and bottom numbers from the rest.

Note: if you have an irregular heartbeat, the most accurate way to measure your blood pressure is with a manual sphygmomanometer at your GP Surgery.

When looking at your average reading, keep in mind:

• Both blood pressure numbers are equally important

 If your top number (your systolic pressure) is in a different category than your bottom number (your diastolic pressure), your correct category is the most abnormal one.

• High Blood Pressure and other Medical Conditions

If you have other medical conditions such as diabetes, kidney disease, heart disease, or you’ve had a stroke, your blood pressure target may be lower than usual recommendations. This is because lowering your blood pressure more aggressively might give you greater benefits, like reducing your risk of complications.

If you’re in the pre-hypertension range and you have other medical conditions, you can speak to your GP, practice nurse or hospital consultant if you’re unsure what your blood pressure target is. 

Blood Pressure Chart

What you do next depends on where your average lies on the blood pressure chart:

Stage                                                      Systolic (mmHg)                 Diastolic (mmHg)

Low blood pressure

                                                                      < 90                                          < 60

Healthy blood pressure

                                                                      90 – 120                                   60 - 80

Pre-hypertension

                                                                      121 – 134                                 81 - 84

Stage 1 hypertension

                                                                      135 – 149                                 85 - 94

Stage 2 hypertension

                                                                      150 – 179                                 95 - 119

Hypertensive crisis

                                                                      ≥ 180                                        ≥ 120

Low Blood Pressure 

If your reading is newly within the Low blood pressure range and you feel well, but don’t usually have a blood pressure this low, book a non-urgent appointment with your GP. 

If you’re feeling newly unwell, seek prompt medical attention, e.g., by ringing your NHS GP in hours, or 111 out of hours. If you feel well (including not feeling lightheaded easily) and this is a typical reading for you, this could be due to athletic fitness, medication, certain medical conditions, or just how your body normally works.

Healthy Blood Pressure

Congratulations – this is great news for your cardiovascular system. Your risk of stroke, heart disease, (and more) will be lower. 

Keep up the good work with plenty of exercise, smart diet choices and other healthy lifestyle behaviours, as well as continuing to monitor your blood pressure occasionally.

Pre-hypertension

If you’re otherwise fit and well, you don’t necessarily need to book a GP appointment. I would still recommend trying to improve your blood pressure, as even slightly raised blood pressure can still increase your risk of serious complications. Why not give yourself 3 – 6 months to make lifestyle changes and then repeat the 7-day monitoring to see what impact your changes had on your blood pressure.

If you have other medical conditions that could affect your blood pressure and are in the pre-hypertension range, you should book a routine GP appointment to see if you should be aiming for a lower target.  

Stage 1 or Stage 2 Hypertension 

If your average reading is in the Stage 1 or Stage 2 hypertension range, it’s important to book a routine appointment with your GP as soon as possible. 

If you don’t act on this, your risk of serious conditions like strokes and heart attacks stays higher. Acting on this can bring it down to a safer level. 

Your GP might first suggest doing a trial period of lifestyle changes to see if your blood pressure can be lowered naturally without medication. It can be helpful to repeat the 7-day Home Blood Pressure Monitoring at the end of the trial and book a follow up to discuss next steps with your GP, including what to do if things haven’t improved.

Generally, GPs will want to start medication for people in the Stage 2 group. If you’re in Stage 1, you may need medication depending on the rest of your medical history.

Hypertensive Crisis

Those with an average blood pressure of >180/120 mmHg should have sought urgent medical attention during the monitoring process anytime their reading was this high, as described in the mybloodpressure.co.uk feedback. 

If your blood pressure is 180/120 mmHg or higher and you have life-threatening symptoms such as chest pain, shortness of breath, or severe confusion, ring 999 or have someone take you to A&E. Otherwise, please sit still and quietly for 5 minutes and repeat the reading. If it’s still in this range but you otherwise feel well, ring your NHS GP in hours, or ring 111 for urgent out of hours support.

For anyone taking part in the 7-day Home Blood Pressure Monitoring, thank you for taking an interest in your heart health and being proactive in improving this. About 5.5 million adults in England alone have high blood pressure without knowing it. This is partly due to it being asymptomatic, so it’s important to monitor your blood pressure regularly and act if your readings aren’t normal.

For more information, please visit Blood Pressure UK.