People diagnosed with high blood pressure in their mid-thirties to mid-forties are more likely to develop dementia in later life than those with normal blood pressure, a study has shown.

The results of the study, published in the American Heart Association journal Hypertension, showed the risk of developing dementia was 61% higher in those diagnosed with high blood pressure between the ages of 35 to 44.

The study also identified a possible link between hypertension and changes to brain structure, as they found that those people with higher than normal blood pressure also had reduced total brain volume. 

The researchers analysed data from UK Biobank – a database containing anonymous health information from around 500,000 participants. They studied MRI scans of more than 22,000 people – half with high blood pressure, and half who did not have hypertension.

Senior author of the study, Professor Mingguang He of the University of Melbourne, said: “Hypertension is very common in middle-aged people (45-64 years), and early onset high blood pressure is becoming more common. 

“Although the association among hypertension, brain health and dementia in later life has been well-established, it was unknown how age at onset of hypertension may affect this association. 

“If this is proven, it would provide some important evidence to suggest earlier intervention to delay the onset of hypertension, which may, in turn, be beneficial in preventing dementia.”

The results highlight the importance of monitoring blood pressure at a younger age, and taking steps to control it, as well as maintain good brain health throughout life. This can be done through living a healthy lifestyle, by getting enough exercise, having good nutrition, reducing stress and more. 

What the researchers found

• The risk of dementia from any cause was significantly higher (61%) in people diagnosed with high blood pressure between the ages of 35 and 44 compared to participants who did not have high blood pressure
• The risk of vascular dementia (a common form of dementia caused by impaired blood flow to parts of the brain) was 45% higher in the adults diagnosed with hypertension between ages 45-54 and 69% higher in those diagnosed between ages 35-44, compared to participants of the same age without high blood pressure
• Although vascular dementia risk was 80% higher in those diagnosed with high blood pressure before age 35, there were fewer cases of dementia among the younger participants, and the association with high blood pressure was not statistically significant, whereas the risk association was meaningful for individuals ages 45-54 with high blood pressure
• In contrast to vascular dementia, no relationship was found between age at hypertension diagnosis and the risk of Alzheimer’s disease, a type of dementia linked to proteins that disrupt brain function