Electroconvulsive therapy response in late-life depression unaffected by age-related brain changes

Abstract

BackgroundGray matter volume decrease, white matter vascular pathology and amyloid accumulation are age-related brain changes that have been related to the pathogenesis of late life depression (LLD). Furthermore, lower hippocampal volume and more white matter hyperintensities (WMH) may contribute to poor response to electroconvulsive therapy (ECT) in severely depressed older adults. We hypothesized that the accumulation of age-related brain changes negatively affects outcome following ECT in LLD. Methods34 elderly patients with severe LLD were treated twice weekly with ECT until remission. All had both 3T structural magnetic resonance imaging (MRI) and β-amyloid positron emission tomography (PET) imaging using 18F-flutemetamol at baseline. MADRS and MMSE were obtained weekly which included 1 week prior to ECT (T0), after the sixth ECT (T1), and one week (T2) after the last ECT as well as at four weeks (T3) and 6 months (T4) after the last ECT. We conducted a multiple logistic regression analysis and a survival analysis with neuroimaging measures as predictors, and response, remission and relapse as outcome variable. ResultsWe did not find any association between baseline hippocampal volume, white matter hyperintensity volume and total amyloid load and response or remission at 1 and 4 weeks post ECT, nor with relapse at week 4. LimitationsThe present exploratory study was conducted at a single center academic hospital, the sample size was small, the focus was on hippocampal volume and the predictive effect of structural and molecular changes associated with aging were used. ConclusionsOur study shows no evidence of relationship between response to ECT and age-related structural or molecular brain changes, implying that ECT can be applied effectively in depressed patients irrespective of accumulating age-related brain changes.