[Psychiatric polypharmacy and electroconvulsive therapy in treatment-resistant depression]

Despite its relevant medical risks, polypharmacy is common particularly among difficult to treat conditions, e.g. treatment refractory depression (TRD). According to numerous guidelines, electroconvulsive therapy (ECT) is the treatment of choice in severe and treatment-resistant major depression due to the high effectiveness; however, to date limited data are available concerning the effects of ECT on the concomitant prescription of psychiatric medication.

For a retrospective explorative analysis of psychiatric polypharmacy (MED) in TRD, data from 58 inpatient treatments were collected. Due to depressive episodes, all patients received psychopharmacological treatment and cognitive behavioral therapy (MED group). Of the patients 29 also underwent ECT (ECT group). Using a modified drug burden index (mod-DBI), the psychiatric medication was quantified at admission (TP0), start (TP1) and termination of ECT (TP2) and discharge in the ECT group or in comparable periods in the MED group (TP3). Differences in distribution were tested with the t-test and alterations in measurements were tested by means of variance analysis (F-test).

Patients treated with ECT showed higher mod-DBI values at TP0, mainly due to more frequent prescription of benzodiazepines (BZD), mood stabilizers (MS) and antipsychotic drugs (AP). At the beginning of the inpatient treatment (TP0-TP1) there was an increase in BZD use (in both groups); in the ECT group MS were reduced and AP increased. In the time interval TP1-TP3, BZD (in both groups) and AP (ECT group) were again less frequently prescribed and MS (ECT and MED group) were increased again. Excluding BZD, there was a significant increase in mod-DBI in both groups, whereas the mod-DBI no longer showed significant differences at TP2 and TP3.

The data possibly indicate that patients with TRD who receive ECT during inpatient treatment already have a more extensive psychiatric medication at admission. Also, psychiatric medication appears to be increased less prominently when ECT is performed. These findings and the possibly associated long-term benefits should be addressed in future research.