Midlife offers the best chance to reduce dementia risk

Our midlife is the ideal time to improve our vascular system’s health and prevent later cognitive decline, researcher Dr Matthew Pase has found.

Examining data from the longest-running study of human health, the Framingham Heart study, Florey researcher Dr Matthew Pase has found that reducing blood pressure and cholesterol, not smoking, maintaining a healthy weight and controlling or preventing diabetes has the largest impact on later brain health.

Vascular dementia is the second most common cause of dementia after Alzheimer’s, accounting for about 20 per cent of cases, or 50 new Australians diagnosed every day.

Wear and tear in the arteries caused by strokes or high blood pressure, which impairs blood flow to the brain, can damage the area responsible for learning, memory and language.

Matthew studied almost 3000 adults from ages 40 to over 90 from the Framingham Heart Study, which has followed residents of the Massachusetts town since 1948.

He compared vascular health risk to brain volume: shrinkage is a measure of overall cell death, reflecting brain health or degeneration.

At every age, poor vascular health was associated with a higher risk of lower brain volume. This link was strongest in the younger people in the study, with brain shrinkage evident in those as young as 45.

The association was also stronger for women at this age than men – an important message that middle aged women need to address their own fitness needs as well as those of their families. Dr Pase said,

“We think of dementia as a disease of old age, but Alzheimer’s has a 30-year lag time before symptoms appear. To have maximal impact, we need to take ownership earlier.”

A second analysis of 40 years of health records of 7800 adults across two generations also found a combined vascular health score at age 45 was more accurate than a later assessment in predicting what the brain would look like in old age.

Importantly, addressing one risk factor wasn’t enough: total vascular health improvement across all measures was needed.

The findings were published in the journal Neurology.

The head of Florey’s dementia research, Associate Professor Amy Brodtmann, said the vascular dementia hypothesis had gained momentum after the The Lancet identified half of the top 10 dementia risks factors — or 12 per cent of global dementia cases — related to vascular health.

There has been a somewhat fatalistic view … that the majority of dementias are genetic. But it’s just not true. The majority are caused by lifestyle factors. It’s a public health message that we’re not doing properly, and midlife actually starts at 35. Get tested for diabetes, get lean, get fit and get your blood pressure checked.

To take part in the Florey’s Healthy Brain Study, tracking 6000 Australians from midlife to find dementia risk factors, head to healthybrainproject.org.au