Causes of dementia: Genetics, high blood pressure, diabetes, obesity are high risk factor

Dementia causes: High blood pressure, diabetes, and cardiovascular diseases damage blood vessels in the brain, reducing oxygen and nutrient delivery. This can lead to strokes, small vessel disease, and other forms of vascular dementia (Image: Canva)

Dementia results in a gradual decline in memory, concentration, and judgment, making it harder for people to manage daily life. While ageing is a primary factor, other contributors include genetics, high blood pressure, diabetes, obesity, poor diets, and lack of exercise.

A recent study conducted by researchers at NYU Langone Health and Johns Hopkins University, published in Nature Medicine, and funded by the National Institutes of Health, reveals that 42 percent of Americans over the age of 55 are at risk of developing dementia, a sharp increase compared to older estimates.

With half a million new cases expected this year in the United States, and projections reaching one million annually by 2060, dementia is becoming a critical public health issue. Additionally, the study found that women are more likely to develop dementia than men, with their risk at 48 percent compared to men’s 35 percent. This is largely because women live longer on average. But what’s driving this surge, and how can it be prevented? Here's what you need to know.

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Causes of dementia

Age-related changes: Dementia is strongly tied to ageing, as brain function naturally declines over time. Structural changes, like shrinkage of the hippocampus (the memory center) and reduced blood flow to the brain, increase susceptibility to cognitive decline. While not all older adults develop dementia, the risk rises significantly after age 65.

Genetics: Certain genetic variants, like the APOE4 gene, significantly increase the risk of Alzheimer’s disease and other forms of dementia. The APOE4 gene impacts how cholesterol and other lipids are transported, contributing to plaque buildup in the brain. People with one or two copies of the gene face a higher likelihood of developing late-onset Alzheimer’s.

Vascular issues: High blood pressure, diabetes, and cardiovascular diseases damage blood vessels in the brain, reducing oxygen and nutrient delivery. This can lead to strokes, small vessel disease, and other forms of vascular dementia. Poor vascular health accelerates cognitive decline, making early management of these conditions crucial.

Lifestyle factors: Obesity, unhealthy diets, and a lack of physical activity contribute significantly to dementia risk. Diets high in processed foods and sugar can lead to inflammation and insulin resistance, while sedentary habits reduce brain plasticity. Adopting a Mediterranean or DASH diet, combined with regular exercise, can lower these risks.

Mental health conditions: Chronic stress, depression, and untreated mental health issues are strongly linked to dementia. Stress hormones, like cortisol, can damage brain cells over time, particularly in areas related to memory. Depression in midlife has also been shown to double the risk of developing dementia later in life.

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Risk factors:

Gender: Women have a higher lifetime risk of dementia (48 percent) compared to men (35 percent), partly due to their longer lifespans.

Ethnicity: Black Americans face a disproportionately higher risk, with cases expected to triple over the next four decades.

Genetic predisposition: Carrying the APOE4 gene variant increases the likelihood of developing dementia by 45 percent-60 percent.

Age: The risk of dementia rises to over 50 percent for those aged 75 and older.

Hearing loss: Untreated hearing problems can increase dementia risk, but only 30 percent of older adults use hearing aids.

Preventive tips:

Maintain heart health: Control blood pressure, cholesterol, and blood sugar levels through medication and lifestyle changes.

Adopt a healthy diet: Follow a balanced diet rich in fruits, vegetables, whole grains, and omega-3 fatty acids.

Stay physically active: Regular exercise can help reduce obesity and improve vascular health.

Engage in mental stimulation: Activities like reading, puzzles, and learning new skills can keep your brain active.

Protect hearing: Use hearing aids if needed and undergo regular hearing tests.

Prioritise mental health: Seek support for stress, anxiety, and depression to protect cognitive function.

Get enough sleep: Quality sleep supports brain health and memory retention.

Address racial health inequities: Improved childhood education and nutrition in underserved communities can lower dementia risks.

Limit smoking and alcohol: These habits can contribute to vascular damage and cognitive decline.

Early screening: Regular cognitive assessments can help identify and manage early signs of dementia.

Disclaimer: This article, including health and fitness advice, only provides generic information. Don’t treat it as a substitute for qualified medical opinion. Always consult a specialist for specific health diagnosis.