Earlier high blood pressure shrinks brain, may increase dementia risk

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In a new study from the University of Melbourne, researchers found people who are diagnosed with high blood pressure at ages 35-44 had smaller brain sizes and were more likely to develop dementia compared to people who had normal blood pressure.

The results raise the possibility that taking steps in young adulthood to control or delay the onset of high blood pressure may reduce the risk of dementia.

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.

In the study, the team analyzed data from participants in the UK Biobank.

They compared magnetic resonance imaging (MRI) results of brain volume between two large groups of adults: 11,399 people with high blood pressure diagnosed at different ages, and 11,399 participants who did not have high blood pressure.

The team found in each diagnostic age category (from 35 to 54), the total brain volume was smaller in people diagnosed with high blood pressure, and the brain volume of several regions was also smaller compared to the participants who did not have high blood pressure.

Hypertension diagnosed before age 35 was associated with the largest reductions in brain volume compared with healthy people.

The team also found the risk of dementia from any cause was much 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 resulting from impaired blood flow to parts of the brain, as might happen after one or more small strokes) was 45% higher in the adults diagnosed with hypertension between ages 45-54 and 69% higher in those diagnosed between ages 35-44.

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.

These results provide evidence to suggest an early age at onset of hypertension is associated with the occurrence of dementia and, more importantly, this association is supported by structural changes in brain volume.

The findings raise the possibility that better prevention and control of high blood pressure in early adulthood could help prevent dementia.

If you care about blood pressure, please read studies about how to keep high blood pressure in check, and findings of high blood pressure drug that may treat vascular dementia.

For more information about health, please see recent studies about Mediterranean diet that could strongly prevent dementia, and results showing this drug can block multiple COVID-19 variants

The study is published in Hypertension. One author of the study is Mingguang He, M.D., Ph.D.

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