May Measurement Month 2022: an analysis of blood pressure screening results from the UK and Republic of Ireland

Abstract

The May Measurement Month (MMM) campaign was carried out in the UK and Republic of Ireland (RoI) in 2022 with the aim of raising awareness of raised blood pressure (BP). Here, we report on the findings of the campaign. Adults aged ≥18 years were recruited opportunistically at hospitals, general practice surgeries, community pharmacies, universities, gyms, and various other public places. Three seated BP readings were taken on each participant, along with completion of a questionnaire on demographics, lifestyle factors, and comorbidities. Hypertension was defined as a systolic BP ≥ 140 mmHg and/or diastolic BP ≥ 90 mmHg or being on antihypertensive medication. Controlled BP was defined as being on antihypertensive medication with a BP < 140/90 mmHg. Multiple imputation was used to estimate any missing BP readings. In total, 3034 were screened, with a mean age of 55.2 (19.0) and 60.2% of whom were female. Of all participants, 1506 (49.6%) had hypertension, of whom 876 (58.2%) were aware, and 798 (53.0%) were on antihypertensive medication. Of those on antihypertensive medication, 382 (47.9%) had controlled BP, and of all participants with hypertension, 25.4% had controlled BP. The proportion of hypertension was similar between males and females, but females had better awareness, greater use of antihypertensive medication, and better medication-controlled BP than males. The MMM campaign in the UK and RoI identified significant numbers of participants with either untreated or inadequately treated hypertension. This evidence underscores the critical need for more effective strategies to improve BP detection and control in order to reduce the significant public health challenge and overall disease burden of hypertension.

Introduction

Raised blood pressure (BP) is one of the largest contributors to the global burden of disease.¹ In the UK, over 7.6 million individuals are living with cardiovascular disease (CVD) and each year this accounts for 27% of all deaths.² Raised BP is the leading modifiable risk factor for CVD and is associated with ∼40% of all cardiovascular events across the UK.² Alarmingly, the estimated prevalence of hypertension is currently 26% in the UK and 32% in the Republic of Ireland (RoI),³ with approximately half of these individuals either living with undiagnosed or uncontrolled hypertension.² Blood pressure awareness and surveillance systems across the UK and RoI are typically implemented through their respective healthcare services and national clinical databases. However, in 2019, only 14% of people registered with a UK general practice were diagnosed with hypertension,⁴ suggesting significant underdiagnosis, which indicates that these centralized approaches are insufficient to identify the true prevalence of hypertension across the wider communities, particularly in those who do not routinely access healthcare services. Accordingly, sub-optimal surveillance, lack of awareness, and inadequate control of BP to national targets present a significant public health problem and are key contributors to the overall disease burden of hypertension.

May Measurement Month (MMM) was initiated in 2017 by the International Society of Hypertension and has run annually since then, except for 2020 due to the COVID-19 pandemic. In 2022, the MMM campaign continued, with the aim of continuing to raise awareness of the dangers of raised BP and included 757 350 participants worldwide.⁵ The UK and RoI participated in MMM in 2017, 2018, 2019, and 2021 and successfully screened 7695, 5000, 10 194, and 1322 participants, respectively, of which 40.3, 34.3, 33.4, and 39.5% were found to have hypertension, with 21.9, 42.8, 29.7, and 41.6% of those individuals taking antihypertensive medications. From these four MMM campaigns, of those receiving antihypertensive treatment, only 59.5, 51.5, 38.2, and 45.7% of participants had controlled BP (<140/90 mmHg).^6-9 These data highlighted the inappropriately high proportion of undiagnosed and uncontrolled hypertension in the community. In this paper, we report on the findings of the MMM22 campaign in the UK and RoI.

Methods

MMM is a cross-sectional opportunistic survey of consenting adults aged 18 years or over. The programmes in the UK and RoI were coordinated by the UK and RoI MMM lead between the months of May and July. Screening sites were set up in hospitals, general practice surgeries, community pharmacies, gyms, workplaces, universities, and various other public places. Investigator-led training days for partners and volunteers taking part in BP screening were conducted prior to screening events. The campaign was promoted by governmental, celebrity, and public health endorsements via social media, national webpages, and newspaper articles.

In accordance with the standard MMM protocol, participants ideally had three seated BP readings measured at 1-min intervals.⁵ Omron devices were predominantly used to measure BP. A questionnaire was also completed, collecting information on demographics, comorbidities, lifestyle risk factors, and antihypertensive medication use. Hypertension was defined as a raised BP (a systolic BP ≥140 mmHg and/or diastolic BP ≥90 mmHg based on the mean of the second and third readings) or being on antihypertensive medication. Controlled BP was defined as being on medication with a BP <140/90 mmHg. Participants found to have raised BP were provided with diet and lifestyle advice and instructed to consult their local healthcare professional for further guidance and investigation.

Data were collected locally via the MMM app or Microsoft Excel spreadsheets. All data were processed locally by Croí (Ireland) and the MMM lead in Wales and then submitted to the central MMM team for cleaning and analysis. In cases where any BP reading was missing, to ensure comparability between participants, the average of the second and third readings was estimated by multiple imputation using chained equations, based on global data as described previously.⁵ For comparison with other countries participating in MMM, results are also presented after age and sex standardization using the World Health Organization (WHO) world standard population and assuming an equal gender split.¹⁰ The study received ethical approval from UK IRAS: 225418.

Results

In total, 3034 were screened during MMM22 in the UK and RoI. The mean (standard deviation) age was 55.2 (19.0) years, and 1825 (60.2%) were female. Data were collected across a range of ethnic groups, with 87.7% of those screened reported as White ethnicity (others included East/Southeast Asian, 2.6%; Black, 1.8%; South Asian, 4.7%; other, 0.6%; mixed, 0.8%; Middle Eastern, 1.5%; and unknown, 0.3%). Of all participants, 103 (3.4%) reported never having had a BP measured before.

Multiple imputation was used to estimate missing BP readings for 940 (31.0%) participants missing data on the second or third BP reading. Of all participants, 1506 (49.6%) were found to have hypertension, of whom 876 (58.2%) were aware, and 798 (53.0%) were on antihypertensive medication (Table 1). Of those on antihypertensive medication, 382 (47.9%) had controlled BP, and of all hypertensives, 25.4% had controlled BP. Of participants who were not taking antihypertensive medication, 708 (31.7%) were found to have raised BP. In total, 1124 (37.0%) were found to have either untreated or inadequately treated hypertension. After age and sex standardization, 1112 (36.7%) were found to have hypertension, of whom 449 (40.4%) were aware, 385 (34.6%) were on antihypertensive medication, and 179 (16.1%) were controlled (Table 1).

Table 1.

Total participants and numbers with hypertension, awareness, on medication, and with controlled blood pressure, before and after age and sex standardization

	Total participants	Number (%) with hypertension	Number (%) of hypertensives aware	Number (%) of hypertensives on medication	Number (%) of those on medication with controlled BP	Number (%) of all hypertensives with controlled BP
Actual	3304	1506 (49.6)	876 (58.2)	798 (53.0)	382 (47.9)	382 (25.4)
Standardized	3030	1112 (36.7)	449 (40.4)	385 (34.6)	179 (46.5)	179 (16.1)

The proportion of those with hypertension was similar among males (51.9%) and females (48.0%). However, females had better awareness (62.6% vs. 52.2%), greater use of antihypertensive medication (56.7% vs. 47.7%), and of those treated, were more likely to have controlled BP (51.3% vs. 41.8%) than males. Finally, those with >12 years of education displayed 17.8 mmHg lower systolic BP compared to those with <1 year of education (P = 0.020).

Discussion

The MMM22 programme identified a total of 1506 (49.6%) participants with hypertension, and 1124 (37.0%) participants with untreated or inadequately treated hypertension, highlighting the scale of hypertension in the UK and RoI. Alarmingly, nearly half of all hypertensives were unaware they had the condition and/or were not receiving antihypertensive medication. Accordingly, the lack of public awareness of raised BP and insufficient control of BP to target remains a major public health issue that needs to be urgently addressed. After age and sex standardization to the WHO population, the percentage with hypertension (36.7%) was more closely aligned to the global estimate (36.0%),⁵ suggesting that the higher percentage of hypertension in those screened in the UK and RoI reflects the high average age of participants and the high proportion of participants arising from medical facilities.

In this current 2022 data set, the proportion of individuals identified as hypertensive (prior to standardization for age and sex) was 49.6%, which is considerably larger than those reported in previous years (2017–21; mean average ∼37%). In addition, the proportion of hypertension awareness (2022: 58% vs. previous campaigns: ∼35%) and the percentage of individuals receiving antihypertensive medication (53% vs. ∼44%) was also higher than previous campaigns. Despite this, the proportion of hypertensives receiving medication with controlled BP remains comparable to the previous campaigns (48% vs. ∼49%). Taken together, the 2022 data indicate that despite a general improvement in both awareness and antihypertensive medication use compared to previous MMM campaigns, the proportion of untreated or inadequately controlled BP has not improved over the past 5 years. Accordingly, the implementation of more effective strategies to improve the detection and control of raised BP remains an urgent public health priority in the UK and RoI.

Interestingly, this year’s campaign revealed that the proportion of hypertension was similar among males and females; however, females had a better awareness, higher use of antihypertensive medication, and a greater proportion of controlled BP than males. Accordingly, further attention is needed to address this disparity in BP awareness and control between males and females. We also observed that a greater number of years in education were associated with lower systolic BP. This suggests that areas in the UK and RoI with lower education levels and/or socioeconomic status could be prioritized as screening sites for future MMM/community-based BP campaigns in order to raise early awareness and reduce longer-term prevalence of hypertension.

The 2022 NHS England Long Term Plan prioritizes detecting, monitoring, and treating ‘A-B-C conditions’ to reduce CVD-related mortality, with an emphasis on improving access to BP monitoring and raising public awareness of CVD.¹¹ Our data highlight that only 3.4% of individuals screened had never had their BP measured before the event, indicating that accessibility to BP measurement is not a major public health issue in the UK and RoI. However, a primary concern is the lack of awareness in those with raised BP and the inadequate control of BP in those with diagnosed hypertension. Similarly, the current data reiterate that UK and RoI primary healthcare BP surveillance databases likely underestimate the true extent of hypertension in the community, with the latest nation-specific registries estimating a prevalence between 26 and 32%.³ Indeed, based on our current data, these GP registration-based reports⁴ appear to underestimate the proportion of hypertension across the UK and RoI by ∼20%. These important findings emphasize the need for focused alignment between primary care and community-based initiatives in order to enhance detection management and monitoring of raised BP across the wider UK and RoI communities.

Strengths and limitations

A strength of the MMM campaign is the use of a standardized protocol across countries, which aids comparability of findings. Participants in MMM were recruited opportunistically using convenience sampling and as a result, prevalence estimates should not be interpreted as estimates of national prevalence. Hypertension was defined based on three BP readings at a single visit for pragmatic reasons, which is not the optimal method of diagnosis at the individual level as recommended in guidelines.¹² Consequently, the rate of hypertension detected is likely to represent an overestimate.

Conclusions

The current data contribute to the growing body of evidence highlighting that poor awareness and inadequate control of BP are significant public health issues across the UK and RoI. The MMM campaign continues to provide valuable insights into the ongoing public health challenges of hypertension and demonstrates that a pragmatic, low-cost, opportunistic screening method can effectively raise awareness and identify individuals at risk. The 2022 data indicate that despite improvements in awareness and antihypertensive medication use compared to previous MMM campaigns, the proportion of controlled BP has not improved over the past 5 years. This underscores the urgent need for more coordinated efforts from national public health authorities and policymakers to promote systematic screening initiatives and implement more effective BP management strategies in order to reduce the national risk and economic burden of hypertension.

Funding

This study was supported by Cardiff Metropolitan University, Manchester Medical School, and Croí, the West of Ireland Cardiac & Stroke Foundation (Ireland).

Data availability

Data are not publicly available but access can be requested with permission from the MMM Management Board, on request through the MMM website: maymeasure.org.