ABSTRACT
To measure the anticonvulsant effects of a course of electroconvulsive therapy (ECT), we used a flexible stimulus dosage titration procedure to estimate seizure threshold at the first and sixth ECT treatments in 62 patients with depression who were undergoing a course of brief pulse, constant current ECT given at moderately suprathreshold stimulus intensity. Seizure threshold increased by approximately 47% on average, but only 35 (56%) of the 62 patients showed a rise in seizure threshold. The rise in seizure threshold was associated with increasing age, but not with gender, stimulus electrode placement, or initial seizure threshold. Dynamic impedance decreased by approximately 5% from the first to the sixth ECT treatment, but there was no correlation between the change in dynamic impedance and the rise in seizure threshold. No relation was found between the rise in seizure threshold and either therapeutic response status or speed of response to the ECT treatment course. These findings confirm the anticonvulsant effect of ECT but suggest that such effects are not tightly coupled to the therapeutic efficacy of moderately suprathreshold ECT.
Subject(s)
Bipolar Disorder/therapy , Depressive Disorder/therapy , Electrocardiography , Electroconvulsive Therapy/methods , Seizures/physiopathology , Adult , Aged , Bipolar Disorder/physiopathology , Bipolar Disorder/psychology , Depressive Disorder/physiopathology , Depressive Disorder/psychology , Dominance, Cerebral/physiology , Evoked Potentials/physiology , Female , Humans , Male , Middle Aged , Personality Inventory , Seizures/psychology , Sensory Thresholds/physiology , Treatment OutcomeABSTRACT
We measured initial seizure threshold by means of a structured stimulus dosage titration procedure in a clinical sample of 111 depressed patients undergoing brief-pulse, constant-current electroconvulsive therapy (ECT). Initial seizure threshold was approximately 60 millicoumbs (mc) (10 Joules) on average, but varied widely (6-fold) across patients. Initial seizure threshold was predicted by four variables: electrode placement (higher with bilateral), gender (higher in men), age (higher with increasing age), and dynamic impedance (inverse relationship). Use of neuroleptic medication was associated with a lower seizure threshold. EEG seizure duration was inversely related to initial seizure threshold, but no other relations with seizure duration were found. These findings may have important clinical implications for stimulus dosing strategies in ECT.
Subject(s)
Bipolar Disorder/therapy , Depressive Disorder/therapy , Electroconvulsive Therapy/methods , Electroencephalography , Adult , Age Factors , Aged , Antipsychotic Agents/administration & dosage , Antipsychotic Agents/adverse effects , Bipolar Disorder/physiopathology , Bipolar Disorder/psychology , Cerebral Cortex/drug effects , Cerebral Cortex/physiopathology , Depressive Disorder/physiopathology , Depressive Disorder/psychology , Dominance, Cerebral/physiology , Electroencephalography/drug effects , Evoked Potentials/drug effects , Evoked Potentials/physiology , Female , Humans , Male , Middle Aged , Premedication , Psychiatric Status Rating Scales , Retrospective Studies , Sensory Thresholds/drug effects , Sensory Thresholds/physiologyABSTRACT
To determine whether structural brain abnormalities in patients with depression are related to cortisol state, we examined the relationship between the dexamethasone suppression test (DST) and brain magnetic resonance imaging (MRI) in 40 inpatients with severe depression referred for electroconvulsive therapy (ECT). Prior to ECT, 27 (68%) of the patients exhibited nonsuppression on the DST. Frontal lobe volume was negatively correlated with peak post-dexamethasone cortisone (r = -0.37) and was 13% smaller in DST nonsuppressors than suppressors; these findings were no longer significant after adjustments for age, gender, and cranial size. Lateral and third ventricular volumes were also correlated with peak postdexamethasone cortisol (r = 0.34 and 0.33, respectively), but not after adjustments for age, gender, and cranial size. Subcortical hyperintensity was associated with peak postdexamethasone cortisol and was more common in DST nonsuppressors than suppressors. Again these findings were no longer significant after adjustments for age. Finally, longitudinal DST and brain MRI studies in 11 of these patients revealed no changes in regional brain volumes nor in postdexamethasone cortisol up to six months after ECT. However, within individual patients, postdexamethasone cortisol was positively (and significantly) correlated with frontal lobe volume.