Mental illness is associated with accelerated ageing, namely with shorter life span and ageing-related diseases such as diabetes or cardiovascular problems, with worse effects observed in men than women (the average lifespan for men having suffered from mental illness is 10 years shorter than for peers without those issues, for women the difference is seven years).
However, despite the knowledge that mental illness accelerates ageing, it was unclear why this was the case. New research seems to give some biological hints to address this question. Researchers at Kings College London analysed a dataset from the UK Biobank including 110,780 patients and tested for 168 different blood metabolites that serve as ageing markers to find a correlation between mental illness and biological indicators of ageing.
Maybe not surprisingly, their results indicated that a history of mental illness was correlated with biological metabolite profiles corresponding to an age older than the chronological age of the patients, which may partially explain why they suffer more age-related diseases and die sooner. For example, the blood markers of people with bipolar disorder indicated an age around 2 years higher than their actual chronological age.
However, this study is only correlational. Although now there is a tangible indicator of accelerated ageing in people with a history of mental disease, the underlying cause for this finding remains to be determined. I wonder if the higher stress loads associated with having a mental disease might be responsible for this finding, and/or whether this is a research avenue that is being followed. It is also interesting to consider whether treating the mental illness would be sufficient to halt ageing-related diseases in this population. In any event, this research shows how important it is to take care of our mental health. As the Roman poet Juvenal said mens sana in corpore sano, one cannot exist without the other.