Hypertension or High Blood Pressure is a rapidly growing health issue across all age groups across the globe with rising prevalence in both adults and adolescents, especially in urban and developing nations. Sedentary lifestyle, obesity and dietary changes are the main culprits. A WHO report on Hypertension in 2023 says that globally, an estimated 1.28 billion adults aged between 30 years to 79 years suffer from hypertension and it is expected to increase up to 1.5 billion in 2025. Less than 1 out of 5 people with hypertension have their blood pressure under control and uncontrolled hypertension remains a major public health challenge. It accounts for about half of all heart disease deaths worldwide followed by stroke which people face due to hypertension. In 2015, ischemic stroke deaths related to high BP were 1.5 million (50% of ischemic stroke deaths), hemorrhagic stroke deaths 2 million (58.3%).
What can Hypertension do to us ?
Despite being easily diagnosable, Hypertension remains one of the leading causes of life-threatening complications, especially related to the brain and nervous system. High blood pressure, is often called the “silent killer” because it can quietly damage our body for years before noticeable symptoms appear. If left uncontrolled, it affects multiple organs and systems, leading to serious health complications. Hypertension can lead to serious health issues including heart attack, heart failure, aneurysm, stroke, cognitive decline , dementia, vision loss, kidney damage, pulmonary hypertension, erectile dysfunction, and even limb loss due to peripheral artery disease.
Hypertension and Brain Health
Hypertension is a major contributing factor to both stroke and aneurysm , two of the most severe and life-threatening consequences of uncontrolled high blood pressure. Elevated blood pressure causes continuous strain on the arteries, weakening their walls over time. In the brain, this can lead to ischemic stroke, where narrowed or blocked arteries restrict blood flow, or hemorrhagic stroke, where a ruptured vessel leads to bleeding within the brain. Both types can result in permanent neurological damage, disability, or death. Additionally, prolonged hypertension increases the risk of cerebral aneurysms—bulging, weakened sections of brain arteries that can rupture unexpectedly, causing a sudden and often fatal hemorrhagic stroke. These conditions are not only medical emergencies but also leading causes of long-term cognitive and physical impairment.
Chronic hypertension damages the structure and function of cerebral blood vessels, leading to both small and large vessel disease, which in turn increases the risk of cognitive decline, vascular dementia, and even Alzheimer’s disease . It is a leading modifiable risk factor for cognitive decline and dementia. Early detection, consistent management and lifestyle changes play a vital role in preserving brain health which helps in reducing the burden of neurological disease, which nearly cripples and leads us to disability.
High BP exerts continuous stress on blood vessels, causing damage and narrowing of the arteries that supply the brain, leading to reduced blood flow and depriving brain cells of vital oxygen and nutrients. Over time, this results in memory loss and forgetfulness due to impaired function, difficulties with attention and concentration from reduced activity in the prefrontal cortex, and slower processing speeds as damage to white matter hampers neural communication. Persistent hypertension also increases the risk of vascular dementia and Alzheimer’s disease by accelerating brain atrophy and the buildup of harmful proteins.
The prevalence of cognitive impairment is significantly higher in people with hypertension. As much as 41% of people are likely to be affected with cognitive impairment compared to those with normal blood pressure, and the risk rises further with more severe hypertension.
Early detection and effective management of Hypertension are crucial to prevent complications of Brain Health
When blood pressure is too high for a long time (hypertension), it can damage the protective barrier in the brain called the blood-brain barrier (BBB). Normally, the BBB acts like a security gate, keeping harmful substances out of the brain while letting in nutrients the brain needs. But with high blood pressure, this barrier can become leaky, allowing toxins and unwanted substances to get into the brain, which can speed up problems with memory and thinking, and increase the risk of dementia.
High blood pressure also reduces the amount of blood flowing to important parts of the brain, especially areas involved in thinking and memory, causing further damage to brain cells. This can make it harder to plan, make decisions, process information quickly, and, to a lesser extent, remember things. Research shows that people with high blood pressure who do not take medication are more than four times as likely to develop problems with thinking and memory, while those who take medication still have about twice the risk compared to people with normal blood pressure.
The good news is that catching and treating high blood pressure early can lower the chance of developing dementia by up to 30% in older adults. In short, keeping blood pressure under control is very important for protecting the brain and staying mentally sharp as we age.
(By, Dr. Sharan Srinivasan, Stereotactic and Functional Neurosurgeon and CMD, PRS Neurosciences and Mechatronics Research Institute)
