Soluble neural cell adhesion molecule and behavioural recovery in minimally conscious patients undergoing transcranial direct current stimulation

Background Transcranial direct current stimulation (tDCS) is used for therapeutic purpose in severely brain-injured patients. The relationship between the recovery after tDCS and potential biomarkers in plasma has been limitedly investigated in patients with minimal conscious state (MCS). Objective To investigate soluble neuronal adhesion molecule (sNCAM) plasma levels in relation to tDCS and recovery processes in MCS. Methods sNCAM was measured in plasma before (T−1,T0), during (T1) and after (T2, T3) tDCS sessions in eight patients with a post traumatic etiology and at least one year of chronic state. Results While sNCAM levels were highly correlated overtime, no significant difference was observed in relation to tDCS. An inverse relation was observed between sNCAM levels at baseline and the tDCS long-lasting effects (T−1, r = −0.852, p = 0.007; T0, r = −0.787, p = 0.020). Conclusions This exploratory research suggests the sNCAM levels, potentially associated with tDCS outcomes, as a candidate biomarker of neurobiological after-effects in MCS patients.