Severe side effects possible for those taking strong medicine to curb high blood pressure, Hong Kong researchers say
Chinese University researchers warn about the consequences of those taking aggressive action to bring their blood pressure down to more normal levels
Stronger doses of medication for patients who experience big blood pressure swings might not cut the risk of developing cardiovascular diseases. Instead, they are more likely to suffer severe side effects such as fainting.
Chinese University of Hong Kong researchers, who analysed data on over 8,000 American patients, discovered that those with bigger blood pressure fluctuations and who tried to push it to a more normal level, were 26 per cent more likely to suffer from the side effects of drugs, compared to those who were less aggressive in controlling their blood pressure.
“[The result] could indicate how we should set treatment goals and who might not need [stronger treatment],” said Professor Samuel Wong Yeung-shan, associate director of the university’s school of public health and part of the research team.
The study also highlighted the importance of long-term monitoring of blood pressure.
“If we could monitor a patient’s data every day, we could more likely check health changes,” said Professor Kelvin Tsoi Kam-fai, also part of the team and an associate professor in the university’s Stanley Ho Big Data Decision Analytics Research Centre.
The research, which was part of a data analysis challenge organised by the top professional publication, The New England Journal of Medicine, and joined by about 140 global teams, attempted to deliver different interpretations of medical information from the same database of a blood pressure study available in the US National Institute of Health data-sharing repository.
By analysing the data set from 8,092 patients with high blood pressure, a high risk of developing cardiovascular diseases and who provided regular blood pressure readings over a period of 18 to 54 months, the Hong Kong team was able to determine that people with bigger blood pressure fluctuations possibly arising from inappropriate drug dosages or not taking drugs on time, were mostly smokers, women and those aged at least 80.
If blood pressure variation is large, it might not be appropriate to control it to a level that is too low
But there was no reduction in the possibility of developing cardiovascular diseases, even if they received intensive treatment to maintain their top blood pressure reading at or below 120 millimetres of mercury (mmHg), compared to those who had standard treatment that kept it at or below 140 mmHg, a figure defining high blood pressure. Instead they faced a higher risk of suffering side effects.
Separately, among patients with steadier blood pressure changes, cardiovascular risks were cut by 34 per cent for those adopting intensive treatment, compared to those on standard programmes.
“If blood pressure variation is large, it might not be appropriate to control it to a level that is too low,” Wong said, highlighting the importance of regular monitoring of blood pressure. Instead they faced a higher risk of suffering side effects.
Tsoi said their experience in using big data analysis provided insights into the development of a local blood pressure database through information collected from smartphones or smart watches, and this could be used to offer more personalised treatment in future.
