Telomere length in psychiatric disorders: Is it more than an ageing marker?

Psychiatric and substance-use disorders have been associated with premature biological ageing. Telomere length (TL), considered an ageing marker, has been analysed in psychiatric disorders, and to a lesser extent in substance-use disorders, with recent findings suggesting TL may be related to disease pathology.

We conducted a critical and non-systematic literature search of TL studies published up to June 2016 in psychiatric and substance-use disorders, focussing on studies describing mechanisms, including studies linking telomere biology with genetic factors, stress and mitochondrial alterations (104 studies selected).

Patients with major depressive disorder and anxiety appear to have shorter leukocyte telomeres compared to controls. Inconclusive results are found for other psychiatric disorders and for substance-use disorders. This may be due in part to differences in medication treatment and response, as studies suggest that some psychotropic medications may modulate TL. Importantly, some studies establish a relationship between telomere machinery, stress and mitochondria function in psychiatric and substance-use disorders.

While further longitudinal studies considering telomere genetics are needed to clarify the cause-effect link between telomeres and mitochondria function in psychiatric and substance-use disorders, the recent findings linking these biological processes suggest that telomeres may be more than ageing markers.