Around 4.2 million adults in England have undiagnosed hypertension, with younger people and those in otherwise good health among those most likely to be unaware they have the condition, figures showed.
Professor Bryan Williams, president of the International Society of Hypertension, described the figures as "shocking but alas, not surprising". Prof Williams, who is a hypertension specialist at University College London Hospitals NHS Foundation Trust, said: "They highlight an ongoing challenge we face in that many people do not get their blood pressure checked and are not aware they have hypertension."
The Office for National Statistics (ONS) estimated that 32% of adults living in private households had hypertension and that among those, 29% were undiagnosed.
The latest statistics revealed that prevalence increased with age for both sexes, with 7% of males and 4% of females aged 16-24 years having hypertension, rising to 66% of males and 71% of females among those aged 75 years and older.
Undiagnosed Younger Adults
However, the latest figures showed that 66% of males and 26% of females with hypertension who were aged 16-24 years were likely to be undiagnosed. Among those aged 25-34 years, the proportion was 55% of males and 44% of females, the ONS reported.
"Our analysis found that while the prevalence of hypertension increased with age and other known risk factors such as high BMI and poor general health, there are considerable numbers of younger, healthier people who are undiagnosed," commented Chris Shrine from the ONS's analytical hub.
Commenting on Twitter , Dr Pauline Swift from the charity Blood Pressure UK said: "In recent years we have seen an increase in younger patients with high blood pressure, often as a result of poor diet, consuming too much salt and lack of exercise leading to weight gain."
When applied across private households, the ONS estimated that 140,000 males and 30,000 females aged 16-24 years had undiagnosed hypertension, compared with 220,000 males and 380,000 females aged 75 years and over.
The ONS analysis estimated that men aged 55-64 years had the highest proportion of undiagnosed cases of hypertension, with around half-a-million cases, followed by women between the ages of 65-74, with around 460,000 cases going undiagnosed.
Prevalence of hypertension for men was highest in the North West of England and lowest in the South East and East of England whilst for women, prevalence was highest in the East Midlands and lowest in the South East.
Adults with hypertension were more likely to be undiagnosed if their self-reported general health was 'very good or good' (males 41%, females 28%) compared with 'fair' (males 21%, females 14%) or 'bad or very bad' (males 18%, females 14%).
Adults from a Black ethnic background, who had no educational qualifications, worked in semi-routine occupations, and were single were at particularly high risk of having hypertension. Other groups most likely to be undiagnosed included males living in rural areas, living in regions other than London, or who had never regularly smoked, and females who were married or in a civil partnership, had degree-level or equivalent qualifications, or who worked for small employers or were self-employed.
The estimate that 32% of the adult population living in private households had hypertension was higher than the 28% figure for 2019, but statisticians said there were differences in the way the condition was defined between the two years. Research published in January this year in the journal Nature Medicine found a decline in the number of antihypertensive medications dispensed during the COVID-19 pandemic between March 2020 and July 2021 in England, Scotland, and Wales, with 491,306 fewer individuals starting treatment than expected.
The ONS analysis, which was based on results from the Health Survey for England, was intended to inform health services, and "may also raise awareness among the general population, leading to more timely diagnoses in the future", said Mr Shine.
Commenting on the statistical analysis, Professor Bryan Williams, president of the International Society of Hypertension, tweeted : "If I have a simple message, it is: get your blood pressure checked and don't ignore it if it is high."