Protein S-100 and neuron-specific enolase serum levels remain unaffected by electroconvulsive therapy in patients with depression

The mechanism of the reversible cognitive deficits that might occur within an electroconvulsive therapy (ECT) treatment has not been clarified in a substantial way yet. Although the data available so far do not point towards a cause due to any structural or diffuse damage, further clarification, especially of the role of S-100 seems to be necessary before robust conclusions can be drawn. Serum levels of protein S-100 and neuron-specific enolase (NSE) were analysed in 19 patients with depression, who received ECT. The sampling was adjusted for the short half-life of protein S-100. Several outcome parameters such as Hamilton Depression Rating Scale and Mini-mental state examination before and after the ECT, response and remission to the treatment were recorded. S-100 and NSE levels at baseline, 30 and 60 min after the third session and after the end of the ECT remained stable. S-100 and NSE levels were neither associated with antidepressant response or remission nor with alterations in the cognitive performance. Although aiming for detecting potential rise in these established brain damage markers, an increase due to ECT was not observed, which is in line with the previous studies concerning the safety of ECT on a cellular basis.