The association between anti-inflammatory effects of long-term lithium treatment and illness course in Bipolar...

Altered levels of acute-phase proteins are often described in different conditions in BD. Nevertheless, data on the association between lithium treatment and inflammatory markers in the long-term course of BD are still missing. The aim of the study was to examine the long-term course of BD concerning long-term lithium treatment, chronic inflammatory processes and symptom progression. Furthermore, the association between duration of lithium treatment and levels of hsCRP was explored.

267 individuals (males= 139, females= 128) with BD were included. Duration of lithium treatment as well as symptom progression, defined as the increase in severity of symptoms, number of episodes a year and duration of episodes within a period of 1.5 years in the past and hsCRP were evaluated.

Male individuals with symptom progression over time had significantly lower duration of lithium treatment compared to individuals without symptoms progression (U= 47.4, p=.037). There were significantly higher levels of hsCRP in male individuals with symptom progression compared to males without symptom progression (U= 47.5, p=.027). Further, there was a significant negative correlation between the duration of lithium treatment and hsCRP levels in the whole sample (r= -.276, p<.05).

Our results show that an altered inflammatory state may be associated with a more severe illness course in BD. Further, a longer duration of lithium treatment may be associated with lower symptom progression. The shown association between hsCRP-levels and lithium treatment duration suggests a potential anti-inflammatory effect of lithium as a mediator of its significant positive outcome effect in BD.