Lower Blood Pressure, More Memory: Controlling Blood Pressure Reduces Dementia Risk

People with high blood pressure are at increased risk of developing dementia because excess pressure can damage blood vessels in the brain. This affects the health of neurons and can lead to memory loss and other cognitive difficulties. Controlling your blood pressure, especially in middle age, can help protect your brain and prevent these types of problems.

High blood pressure, especially when not properly treated, has been linked to an increased risk of developing dementia, including Alzheimer’s disease, and other forms of cognitive impairment.

This is because hypertension (i.e., high blood pressure in the arteries) can damage blood vessels in the brain over time, impairing the delivery of oxygen and essential nutrients to brain cells.

This process can lead to the death of neurons, the formation of microscopic lesions, and reduced connectivity between different brain regions, all of which contribute to the decline in memory, attention, and other mental functions.

In recent years, studies have shown that controlling blood pressure, especially in middle age, can be an effective strategy for protecting the brain and reducing the risk of dementia in old age.

Dementia is one of the leading causes of death and loss of autonomy worldwide, especially among older people. In this study, researchers at UT Southwestern Medical Center, USA, wanted to find out whether better control of blood pressure could help prevent cases of dementia.

They did this in a population of almost 34,000 people over the age of 40 who lived in rural areas of China and who had poorly controlled high blood pressure.

To test the idea, the researchers divided 326 villages into two groups: in half of them (163 villages), residents participated in a special program with supervision by community health professionals (not doctors) who were trained to help people take their medication correctly and to adjust treatment as needed.

Considering normal blood pressure as 120 mmHg systolic and 80 mmHg diastolic (12/8), the goal was to lower the maximum (systolic) pressure to less than 130 mmHg and the minimum (diastolic) pressure to less than 80 mmHg, under the supervision of local doctors. The other half of the villages continued with normal care, as was done before.

After following these people for four years (48 months), the study showed that the group with intensive treatment had a significant drop in blood pressure: maximum pressure fell, on average, by 22 mmHg, and minimum pressure fell by 9 mmHg compared to the group that maintained the usual treatment.

And most importantly, fewer people developed dementia in this group with better controlled blood pressure, a 15% reduction in the risk of dementia compared to the other group.

Furthermore, the intensive intervention group also had fewer serious complications related to treatment, showing that the approach was not only effective but also safe.

These results indicate that lowering blood pressure more aggressively may be an effective way to prevent dementia in people with hypertension, especially in areas with limited access to medical services.

READ MORE:

Blood pressure reduction and all-cause dementia in people with  uncontrolled hypertension: an open-label, blinded-endpoint, cluster-randomized trial

Jiang He, Chuansheng Zhao, Shanshan Zhong, Nanxiang Ouyang, Guozhe Sun, Lixia Qiao, Ruihai Yang, Chunxia Zhao, Huayan Liu, Weiyu Teng, Xu Liu, Chang Wang, Songyue Liu, Chung-Shiuan Chen, Jeff D. Williamson, and Yingxian Sun 

Nature Medicine. 21 April 2025

https://doi.org/10.1038/s41591-025-03616-8

Abstract:

Dementia is a leading cause of death and disability worldwide. Here we tested the effectiveness of blood pressure (BP) reduction on the risk of all-cause dementia among 33,995 individuals aged ≥40 years with uncontrolled hypertension in rural China. We randomly assigned 163 villages to a non-physician community healthcare provider-led intervention and 163 villages to usual care. In the intervention group, trained non-physician community healthcare providers initiated and titrated antihypertensive medications according to a simple stepped-care protocol to achieve a systolic BP goal of <130 mm Hg and a diastolic BP goal of <80 mm Hg, with supervision from primary care physicians. Over 48 months, the net reduction in systolic BP was 22.0 mm Hg (95% confidence interval (CI) 20.6 to 23.4; P < 0.0001) and that in diastolic BP was 9.3 mm Hg (95% CI 8.7 to 10.0; P < 0.0001) in the intervention group compared to usual care. The primary outcome of all-cause dementia was significantly lower in the intervention group than in the usual care group (risk ratio: 0.85; 95% CI 0.76 to 0.95; P = 0.0035). Additionally, serious adverse events occurred less frequently in the intervention group (risk ratio: 0.94; 95% CI 0.91 to 0.98; P = 0.0006). This cluster-randomized trial indicates that intensive BP reduction is effective in lowering the risk of all-cause dementia in patients with hypertension. ClinicalTrials.gov: NCT03527719.