Association between hippocampal volume change and change in memory following electroconvulsive therapy in late-life depression

Objective: Electroconvulsive therapy (ECT)-induced hippocampal volume change (HVC) has been repeatedly described in recent years. The similar time course of HVC and ECT-related cognitive effects suggest a relation, that is to date, understudied. This study investigates whether HVC following ECT predicts the change in memory performance six months after the end of the ECT treatment. Methods: Hippocampal volume (HV) was measured via high-resolution 3D T1-weighted images in 88 patients with late-life depression, within 1 week before and after ECT. Memory performance was assessed before and six months after ECT. Multiple linear regression was used to examine whether change in memory performance could be predicted based on ECT-induced changes in HV. Results: Larger right absolute HVC predicts less pronounced improvement on the VAT (visual memory) in the whole sample. For the 8-Word Test (verbal memory), Category Fluency Test (semantic memory), and MMSE, the effect is only present in patients who switched from right unilateral to bitemporal stimulation after six ECT sessions. Absolute HVC in the left hemisphere was not significantly related to cognitive change. Conclusion: A larger absolute change in right HV during ECT is associated with less improvement in memory performance up to 6 months post-ECT.