Research has already linked high blood pressure with an increased risk of a severe case of COVID-19. Now, a new study out of the United Kingdom identifies at what level high blood pressure can help predict a life-threatening case of the virus.
The greatest risk is among people whose systolic blood pressure (SBP, or the top number in a blood pressure reading) was above 150, according to the study published Wednesday in the journal PLOS One.
“We found that in those with diagnosed hypertension, the risk of COVID-19 significantly increased once the high number exceeded 150 mmHg or the low number exceeded 90 mmHg compared to a target blood pressure (120-129/80-89 mmHg),” said lead author Holly Pavey, a doctoral student at the University of Cambridge, according to CNN.
The findings were based on data from 16,134 people in the United Kingdom who tested positive for COVID-19. Among them, 40% had high blood pressure and 22% got severe COVID-19.
The findings expand on a previous study, published in July, that showed that high blood pressure more than doubles the risk of a severe case of COVID-19, even among people who are vaccinated and boosted.
“Our study also suggests that there are further effects influencing the severity of COVID-19 beyond a dichotomous diagnosis of hypertension,” the authors wrote. “Individuals with a higher than target SBP, may be less healthy, less active, suffering more severe hypertension or have developed drug resistant hypertension, all suggesting that the effects of hypertension have already had detrimental physiological effects on the [cardiovascular] system, which in turn may offer some explanation for the higher risk of severe COVID-19 with uncontrolled SBP.”