People with high blood pressure may be at increased risk of developing brain tumours, new research suggests.
Some 12 million people in the UK are diagnosed with high blood pressure while another 5.7 million are thought to have the condition but are unaware of it.
Experts analysed data for almost 580,000 people from Sweden, Austria and Norway, who were followed for around 10 years.
Data on brain tumours was obtained from national cancer registries and, during follow-up, 1,312 brain tumours were diagnosed.
People were typically aged 41 at the start of the study and the typical age of diagnosis was 56 for a brain tumour. The most common tumours diagnosed were meningioma and glioma, which each account for around one third of all brain tumours.
Writing in the Journal of Hypertension, the experts said those 20 per cent of participants with the highest blood pressure readings were more than twice as likely to later be diagnosed with meningioma or malignant glioma compared with the 20 per cent with the lowest readings.
But they said more research is needed before it is possible to be confident that high blood pressure really does increase risk of brain tumours.
Some 9,000 cases of brain tumour are diagnosed in the UK every year.
The study, by researchers from Austria, Norway and Sweden, was funded by World Cancer Research Fund.
Michael Edlinger, epidemiologist at the medical statistics department in Innsbruck, Austria, and lead researcher of the study, said: “These results are interesting because the large number of people in this study and the fact that more than 1,000 of them developed brain tumours mean it is unlikely that the findings are down to chance.
“But this does not mean we can be confident that it is the high blood pressure that has caused the increase in brain tumour risk, as there are some limitations to our study.
“More research is needed into whether high blood pressure increases risk of brain tumour.”