Mental illnesses linked to faster ageing

Biological age of people with bipolar is two years older than they actually are, researchers show

PEOPLE with a mental illness have a biological age that is two years older than they actually are, a study has found.

People with anxiety, bipolar and depression suffer from worse physical health, and scientists may have found evidence to suggest this is because mental health is linked to the speed at which the body ages.

Dr Julian Mutz, a postdoctoral researcher at King’s College London, led a project which analysed data on 168 different blood metabolites (products of metabolism) from 110,780 participants in the UK Biobank study.

Dr Mutz said: “We examined biological ageing in people with bipolar disorder, depression or anxiety disorder. We found that people with a history of mental illness had an older biological age than their actual age.

“The differences were largest for people with bipolar disorder, smallest for people with anxiety disorder and depression was somewhere in between.

“We observed the largest difference between biological age and actual age in people with bipolar disorder, a mean difference of about two years.

“For depression the corresponding difference was about one year and for anxiety disorder it was 0.7 years.

“The finding that these differences were greatest in people with bipolar disorder is something that we observed for other measures of biological ageing, for example when looking at frailty.”

According to the researchers, their findings may go some way to explaining why people with mental health problems tend to have shorter life spans and more age-related diseases than the general population.

Dr Mutz added: “It is now possible to predict people’s age from blood metabolites.

“We found that, on average, those who had a lifetime history of mental illness had a metabolite profile which implied they were older than their actual age.” The study was presented at the European Congress of Psychiatry in Paris, where Dr Mutz said that while the data did not prove causation, it opened up avenues for future research.

“There are several plausible pathways linking psychiatric disorders to accelerated biological ageing,” he said.

“For example, lifestyle – such as physical inactivity and higher rates of smoking; biology – such as overactivation of the autonomic nervous system and chronic low-grade inflammation; and psychosocial factors – such as social isolation and loneliness, in people with mental illness likely negatively impact biological ageing and their health, highlighted by the higher prevalence of agerelated diseases and lower life expectancy.

“I would speculate that it is a mutually reinforcing process: mental illness negatively impacts ageing, and faster biological ageing and poor health in turn negatively impacts mental health.”

The study has not yet been published in a journal but the team is hoping to submit the work for publication in the next few months.