By Sharon Atieno
Managing high blood pressure (hypertension) could lead to a reduced risk of dementia- the loss of cognitive functioning, including remembering, thinking and reasoning to an extent that it interferes with a person’s daily life activities.
Prof. Raj Kalaria, Professor of Neuropathology, Translation and Clinical Research Institute, Newcastle University, said during the Alzheimer’s Association International Conference (AAIC) Neuroscience Next Hub hosted by the Aga Khan University’s Brain and Mind Institute in Nairobi, Kenya.
Prof. Kalaria observed that hypertension is the strongest modifiable risk factor. Others include diabetes, high lipids, smoking and air pollution, among others.
“Knowing you have high blood pressure and getting treated or somehow changing your lifestyle so that the pressure comes down has been calculated to reduce 20-25% of the burden of dementia,” he said.
Prof. Kalaria observed that high blood pressure leads to arteries losing their ability to contract, affecting the blood flow supply to the brain. “This could be so low that it affects the passage of blood to the brain and transform nutrients between blood and brain including glucose and oxygen and so on and that can affect the health of the neurons or nerve cells, what we call the neurovascular unit,” he said.
“If those units are affected, then it could affect pathways in the brain. This then affects the wiring of the brain and can lead to cognitive decline and dementia.”
Long-term research studies have demonstrated that people who had high blood pressure in mid-life (from 40-64 years of age) were more likely to develop dementia in later life, particularly vascular dementia.
According to the Alzheimer’s Society, vascular dementia is the second most common form of dementia after Alzheimer’s disease. It is caused by reduced blood flow to the brain, which starves brain cells of the oxygen and nutrients they need to function correctly.
Globally, more than 55 million people lived with dementia in 2020, according to Alzheimer’s Disease International. By 2030, the number will rise to 78 million and will reach 130 million by 2050.
The World Health Organization (WHO) estimates that about two in three people living with the condition are in low- and middle-income countries.
Dementia is currently the seventh leading cause of death and one of the major causes of disability and dependency among older people globally.
