Another winner from Sweden’s Karolinska Institute, the world-renowned medical ­research centre that’s been gathering information about who’s likely to get Alzheimer’s.

Each new project provides another piece of the jigsaw and we’re creeping towards getting the full picture. This one reveals people who have a higher biological age than their actual chronological age have a significantly increased risk of stroke and dementia, especially vascular dementia.

The study, led by associate professor Sara Hägg and doctoral student ­Jonathan Mak, both from Karolinska Institute, shows this increased risk persists even if other risk factors such as genetics, lifestyle and ­socioeconomics are taken into account. As we age, risk of chronic diseases such as cancer, cardiovascular disease and neurodegenerative disorders increases, and chronological age, the number of years a person has been alive, has been used as an approximate measure of biological age.

“But because people age at different rates, chronological age is a rather imprecise measure,” says Hägg. It turns out that what’s important is biological age. In order to measure biological age and the link to disease, the researchers studied 325,000 people who were between 40 and 70 years old at the time of the first measurement.

Biological age can be calculated using 18 biomarkers, including blood fats (e.g. cholesterol), blood sugar, blood pressure, lung function and BMI. The researchers then investigated the relationship between these biomarkers and the risk of developing neurodegenerative diseases such as dementia, stroke, motor neurone disease and Parkinson’s disease within a nine-year period.

Compared to actual chronological age, high biological age was linked to a significantly increased risk of dementia, especially vascular dementia, and ischemic stroke (such as a blood clot in the brain). “If a person’s biological age is five years higher than their actual age, the person has a 40% higher risk of developing vascular dementia or suffering a stroke,” says Mak.

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. And die at an older age. The good news is several of the values can be influenced through ­lifestyle and medications, says Hägg.

However, no such risk increase was seen for Parkinson’s disease. Hägg adds: “We already know that Parkinson’s disease is a bit unique in other contexts as well, for example, when it comes to smoking.” The researchers will now proceed to investigate the connection between biological age and other diseases such as cancer. Brilliant research.