• late onset bipolar disorder
• cerebral small vessel disease
• elderly patients
• vascular depression
• electroconvulsive therapy

Abstract
Objectives: Cerebral Small Vessel Disease (CSVD) is a chronic, progressive vascular disorder that confers increased vulnerability to psychiatric syndromes, including late-life mood disorders. In this study, we investigated the impact of CSVD on electroconvulsive therapy (ECT) outcomes in patients with late-onset bipolar disorder (LOBD).
Methods: A sample of 54 non-demented elderly patients (≥60 years) with LOBD and treatment-resistant major depression, mixed state, or catatonia who underwent bilateral ECT were included in this naturalistic observational study. A diagnosis of CSVD was established based on brain neuroimaging performed before ECT. All patients were evaluated before and after ECT using the Brief Psychiatric Rating Scale (BPRS), the Hamilton Rating Scale for Depression (HAM-D), and the Clinical Global Impression scale (CGI).
Results: Of the total sample, 19 patients were diagnosed with CSVD (35.2%). No significant differences were observed at baseline between patients with and without CSVD. Overall, a response was obtained in 66-68.5% of patients, with remission in 56.2%. No significant differences in ECT outcomes were found between those with and without CSVD, and both groups exhibited substantial improvements in symptom severity following ECT.
Conclusions: The outcome of ECT in LOBD was not influenced by the presence of CSVD. This finding aligns with previous research on unipolar depression. Accordingly, ECT should be considered for elderly patients with LOBD, regardless of the presence of CSVD.