Ambulatory Blood Pressure Measurement (ABPM) has been used increasingly in clinical practice over the last 30 years. With the rise and adoption of low cost home blood pressure monitoring is it still an indispensable tool in the management of hypertensives in General Practice?
I first asked this question in an article I wrote for Practice Management magazine in 2010. I concluded that it was but in the intervening years is this still the case?
In the light of clinical developments and the publication of guidelines like NICE Guideline CG127 on Hypertension in 2011 and latest update in November 2016 is it still relevant?
Some background
In recognition of the importance of ABPM, the British Hypertension Society (now the British and Irish Hypertension Society), the European Society of Hypertension and NICE CG127 have all published guidelines for the use and interpretation of ABPM in clinical practice.
Traditionally, hypertensive patients had been assessed using clinic based blood pressure readings by a Nurse or Doctor. This changed in 2011 and recognition was formally given to the importance of using 24 hour ABPM monitoring.
The old “snapshot” approach to blood pressure measurement could give inconsistencies and over-estimate a patient’s blood pressure by anything up to 30mmHg.
The so called White Coat Hypertension, leading to elevated blood pressure is well documented and can lead to unnecessary prescription of hypertensive medicines. This has a profound clinical and financial relevance to Primary Care and can lead to inappropriate diagnosis and treatment. Ambulatory Blood Pressure Monitors provide much more consistent readings over a 24-hour period and give multiple measurements throughout the day and night.
CardioVisions NICE Software keeps it simple.
Modern ABPM software can produce a plethora of statistics and data which even for experienced clinicians can be overwhelming.
As a response to this and in view of the 2011 NICE guidelines we introduced our CardioVisions NICE software. This provided a meaningful textual analysis ensuring clinicians got reporting continuity to a recognised clinical standard as well as importantly saving Doctor and Nurse time. It’s compatible with the Meditech ABPMs and a typical report may read something like this.
“The ABPM was worn by the patient for 24 hours. During this period the average daytime blood pressure was 169/118 and the pulse rate was 88 beats per minute. According to NICE guidelines the patient exhibits stage 2 hypertension. The examination was divided into day 06:00-22:00, night 22:00-06:00. 64 successful readings were taken during the daytime period and the NICE key quality requirement for 14 has been met. During the daytime there were 64 readings (100.0%) above the NICE guideline figure of 135/85. The highest reading was 202/134 recorded at 9:15 22/05/1997. During the night time period 24 successful readings were taken and the average blood pressure was 135/87.”
The detailed stats, graphs and readings are still there for those that want them but the textual analysis summary can be copied and pasted into the patient notes and also attached to popular clinical management systems like EMIS Web and SystmOne. There is no annual licence fee and multiple copies can be installed.
What about home blood pressure monitoring?
The cost of clinically validated home blood pressure monitors has fallen since 2010 and a number of GP Practices have been loaning monitors like the UA-767S-W to patients. Home monitoring is great for the small number of patients that find ambulatory blood pressure monitoring inconvenient or difficult tolerate but it’s not ideal for everyone and can be difficult to manage in practice.
For home blood pressure monitoring NICE recommend patients should measure their blood pressure twice a day, ideally once in the morning and once in the evening, while sitting down. Each time they do this, they should take two readings, 1 minute apart. They should continue to measure their blood pressure twice daily for at least 4 days and ideally for 7 days. Some patients may find this onerous and patient compliance can vary. A 24 hour monitor is only worn for 24 hours!
All the measurements taken after the first day are used to work out average day time blood pressure but again this can be time consuming and may be subject to error.
Whilst home blood pressure monitoring gives multiple readings, it relies on proper patient technique, patient training and compliance for up to seven days to give meaningful results.
As a complementary technique to 24 hour ABPM it can be useful to monitor patients with long term chronic conditions such as diabetes and coronary heart disease.
On the flip side the detail, automatic analysis and reporting, 24 hour ABPM provides with very little user or patient input just isn’t available with home blood pressure monitoring.
Night time readings cannot be recorded and for many 24 hour ABPM remains the “Gold Standard”.
So why doesn’t everyone use 24 hour ABPM?
For some the initial cost is off putting but the cost of 24 hour ABPM monitors has fallen since 2010.
The latest 24 hour BP monitors like the Meditech ABPM-04 and ABPM-05 are reliable with low running costs, long warranties and a low overall cost of ownership.
PMS Instruments now offer a flexible rental ABPM service which means cost can be spread over several months and for a low monthly fee service and calibration is covered.
“Is 24 Hour ABPM Still An Indispensable Tool In Management Of Hypertension?” my answer would still be yes.
To arrange a free trial of one of our latest ABPM monitors and find out for yourself please contact us on 01628 773233.
