People who have a higher biological age than their actual chronological age have a significantly increased risk of stroke and dementia, especially vascular dementia, new research has revealed.

The study, published in the Journal of Neurology, Neurosurgery and Psychiatry, showed that the increased risk persists even if other risk factors such as genetics, lifestyle and socioeconomics are taken into account.

“Because people age at different rates, chronological age is a rather imprecise measure,” said Associate Professor Sara Hagg from Karolinska Institutet in Sweden.

In order to measure biological age and the link to disease, the researchers used data from the UK Biobank. They studied a cohort of 325,000 people who were all between 40 and 70 years old at the time of the first measurement. Biological age was calculated using 18 biomarkers, including blood lipids, blood sugar, blood pressure, lung function and BMI.

When compared to actual, chronological age, high biological age was linked to a significantly increased risk of dementia, especially vascular dementia, and ischemic stroke, (i.e. blood clot in the brain).

“If a person's biological age is five years higher than their actual age, the person has a 40 per cent higher risk of developing vascular dementia or suffering a stroke,” said doctoral student Jonathan Mak.

As it is an observational study, causal relationships cannot be established. However, the results indicate that by slowing down the body's ageing processes in terms of the measured biomarkers, it may be possible to reduce or delay the onset of disease.