Hypertension poses major health risk for patients in middle income countries

Many people diagnosed with hypertension in four of the world’s biggest middle-income countries stop treatment and most of these patients lose control of blood pressure – potentially leading to heart problems and death, a new study reveals.

Analysing patient data from China, Indonesia, Mexico, and South Africa, experts found that policies solely aimed at improving diagnosis or initiating treatment may not lead to long-term hypertension control improvements in these and similar countries.

Researchers investigating how people with hypertension move through care over time looked at adults aged 40 and over. They discovered that over a 5- to 9-year follow-up period, only around 30% of undiagnosed individuals became diagnosed, whilst 25% of untreated individuals became treated.

The most striking finding, however, was that among those that were on treatment and had controlled blood pressure, the majority lost blood pressure control and a substantial number stopped treatment over the 5- to -9-year period.

Publishing their findings in Science Translational Medicine, the international group of researchers – including the University of Birmingham and Technical University of Munich – observed that:

• South Africa had the lowest rates of undiagnosed hypertension, treatment discontinuation and blood pressure control loss, as well as the highest probabilities of individuals reaching blood pressure control.

• China had one of the lowest rates of reaching blood pressure control with just 9% of individuals likely to achieve this – regardless of treatment status.

• In Indonesia, 92% of individuals lost blood pressure control at follow-up, with the country also displaying the highest treatment discontinuation and lowest treatment initiation rates - suggesting substantial barriers in accessing and following up care.

• In Mexico, only 27% of people were likely to be diagnosed with hypertension, whilst 34% of individuals with a diagnosis later discontinued their treatment.

Professor Justine Davies from the University of Birmingham commented: “Hypertension affects one in four adults and is the world’s leading cause of cardiovascular disease and early death. Two-thirds of people with hypertension live in low- and middle-income countries and these countries in particular face considerable population ageing, which is likely to generate a surge in people requiring hypertension care. Treating hypertension substantially reduces deaths from cardiovascular disease mortality, yet many countries have crucial gaps in hypertension diagnosis and control.”

Nikkil Sudharsanan, Assistant Professor of Behavioral Science for Disease Prevention and Health Care at Technical University of Munich, commented: “Our analysis covered four large middle-income countries making up close to a quarter of the world’s population. We found that diagnosis and treatment initiation are major bottlenecks to achieving blood pressure control. Nonetheless, treatment discontinuation and loss of blood pressure control are equally problematic and reveal that we can’t expect long-term hypertension control from interventions that seek to improve diagnosis and treatment initiation without efforts to also keep people in care and their blood pressure controlled over time.”

Only 21 MICs out of 106 classified by the World Bank are on track to achieve Sustainable Development Goal target 3.4 of reducing premature mortality from noncommunicable diseases (NCDs) by one third by 2030.

ENDS

For more information, please contact Tony Moran, International Communications Manager, University of Birmingham on +44 (0)782 783 2312 or t.moran@bham.ac.uk. For out-of-hours enquiries, please call +44 (0) 7789 921 165. 

Notes for editors

• The University of Birmingham is ranked amongst the world’s top 100 institutions. Its work brings people from across the world to Birmingham, including researchers, teachers and more than 6,500 international students from over 150 countries.
• ‘Treatment discontinuation, adherence, and loss of 1 hypertension control. Longitudinal evidence from four middle-income countries’ - Nicole Mauer, Pascal Geldsetzer, Jennifer Manne-Goehler, Justine I. Davies, Andrew C. Stokes, Margaret McConnell, Mohammed K. Ali, Volker Winkler and Nikkil Sudharsanan is published in Science Translational Medicine.
• Participating institutions include:
  • University of Birmingham
  • Technical University of Munich, Germany
  • Heidelberg University, Germany
  • Stanford University, USA
  • Chan Zuckerberg Biohub, San Francisco, USA
  • Harvard T.H. Chan School of Public Health, Boston, USA
  • University of Witwatersrand, Johannesburg, South Africa
  • Boston University, USA
  • Emory University, Atlanta, USA
  • University of Munich, Germany
  • European Observatory on Health Systems and Policies, Brussels, Belgium