Could lowering blood pressure help protect your brain?

We often hear about blood pressure in relation to heart attacks and strokes. A new study adds another reason to pay attention to it: the health of the brain’s tiny blood vessels.

Researchers revisited brain scans from the SPRINT blood pressure trial. The people in this analysis were aged 50 or older and had high blood pressure. One group had been assigned a more intensive systolic blood pressure target of below 120 mmHg; the other had a target of below 140 mmHg. Systolic pressure is the top number in a blood pressure reading. Over roughly four years, the intensive treatment group showed less progression of small vessel disease on MRI scans. Scholars @ UT Health San Antonio

What is small vessel disease?

It refers to changes affecting the brain’s smallest blood vessels. Researchers can see signs of these changes on an MRI. Small vessel disease is linked with stroke and difficulties with thinking and memory, which is why it matters to dementia research. This study combined three MRI measures to look at the overall change in those vessels. Scholars @ UT Health San Antonio

What did the researchers find?

People assigned the lower blood pressure target had less progression on the combined brain scan measure than those assigned the standard target. The researchers also found that greater reductions in systolic blood pressure were associated with more favourable scan results. Even reductions of up to 10 mmHg were associated with a measurable difference. Scholars @ UT Health San Antonio

That is encouraging, but a better brain scan is not the same as proof that someone will avoid dementia. This particular analysis measured signs of small vessel disease. It did not establish how many dementia diagnoses were prevented. It was also a later analysis of a subgroup of the original trial, so its results need to be read in that context. Scholars @ UT Health San Antonio

What does this mean for us?

The message is simple: know your blood pressure and manage it with your health professional. High blood pressure often has no obvious symptoms, so feeling well does not tell you what your numbers are. An Australian Heart Health Check can include blood pressure, cholesterol and blood sugar, along with a discussion of your overall risk. Heart Foundation

The study’s below 120 target is not a number everyone should try to reach on their own. The right treatment and target depend on the person. If you already take blood pressure medication, speak with your GP before making changes. Your GP can also help you work on habits that support blood pressure, including movement and food choices. Heart Foundation

The HEAL takeaway

A walk or a nourishing meal is a visible step towards better health. Booking a blood pressure check may feel less exciting, but it could be just as valuable. Small changes for big gains includes knowing your numbers and getting support to manage them.

Read the original research · Read the university’s plain-language summary