Multiple long-term conditions in midlife increases dementia risk

Researchers from the UK and France have found that having two or more chronic conditions in middle age is associated with an increased risk of dementia later in life. The findings were published today (Wednesday 2 February) in the BMJ.

The researchers used information from the Whitehall II study, a long-term health study that recruited people working as civil servants in the 1980s.

When volunteers joined the study between 1985-88 they were aged 35 to 55 and did not have dementia.

Researchers looked at people who did have two ‘chronic’ conditions, out of a list of 13 conditions.

The chronic conditions people may have had and were looked at in the study were:

At the age of 55, 6.6% of study volunteers had two or more diseases.

Having two or more diseases at age 55 was associated with a higher risk of dementia compared with people without any of the 13 chronic conditions.

The number of people with two or more chronic diseases increased as people got older, with 32% of people having two or more diseases at age 70. This was still linked with an increased risk of dementia but the link was not as strong.

When the researchers looked at those with three or more chronic conditions, the time at which people developed the health condition had even more bearing on subsequent dementia risk.

Dr Rosa Sancho, Head of Research at Alzheimer’s Research UK, said:

“One in three people born today will go on to develop dementia in their lifetime. Age, genetics, and lifestyle are all risk factors for developing the condition, but we know age is also a major risk factor for the development of other health conditions. “In this research, scientists looked at whether people with more than one chronic disease during midlife were more at risk of developing dementia in later life. While this group of volunteers is not reflective of the UK population as a whole, it is a large group that offers valuable insight into the relationship between multiple health conditions in midlife and dementia later in life. “Large, long-term studies like this are good for highlighting links, but we need research to explore the mechanisms between individual conditions. This insight will enable researchers to design and deliver appropriate interventions that will reduce the number of people who go on to develop dementia. “It is important to properly manage long-term health conditions and people who have concerns about any aspect of their health should speak to their GP. We do know that it’s never too early or too late in life to take action on brain health and there are things we can do to reduce our risk of dementia. This includes not smoking, only drinking in moderation, staying mentally and physically active, eating a balanced diet, and keeping cholesterol and blood pressure levels in check can all help to keep our brains healthy as we age. Find information and advice on brain health at www.thinkbrainhealth.org.uk” You can read the full paper ‘Association between age at onset of multimorbidity and incidence of dementia: 30-year follow-up in Whitehall II prospective cohort study’ in the BMJ.