Strategic infarct locations for post-stroke depressive symptoms: a lesion- and disconnection-symptom mapping study
BackgroundDepression is the most common neuropsychiatric complication after stroke. Infarct location is associated with post-stroke depressive symptoms (PSDS), but it remains debated which brain structures are critically involved. We performed a large-scale lesion-symptom mapping study to identify infarct locations, and white matter disconnections, associated with PSDS. MethodsWe included 553 patients (age 69{+/-}11 years, 42% female) with acute ischemic stroke. PSDS were measured using the 30-item Geriatric Depression Scale (GDS-30). Multivariable support vector regression (SVR)-based analyses were performed both at the level of individual voxels (SVR-VLSM) and predefined regions of interest (SVR-ROI) to relate infarct location to PSDS. We externally validated our findings in an independent stroke cohort (N=459). Finally, disconnectome-based analyses were performed using SVR-VLSM, in which white matter fibers disconnected by the infarct were analyzed instead of the infarct itself. Results: Infarcts in the right amygdala, right hippocampus and right pallidum were consistently associated with PSDS (permutation-based p<0.05) in SVR-VLSM and SVR-ROI. External validation (N=459) confirmed the association between infarcts in the right amygdala and pallidum, but not the right hippocampus, and PSDS. Disconnectome-based analyses revealed that disconnections in the right parahippocampal white matter, right thalamus and pallidum, and right anterior thalamic radiation were significantly associated (permutation-based p<0.05) with PSDS. ConclusionsInfarcts in the right amygdala and pallidum, and disconnections of right limbic and frontal cortico-basal ganglia-thalamic circuits, are associated with PSDS. Our findings provide a comprehensive and integrative picture of strategic infarct locations for PSDS, and shed new light on pathophysiological mechanisms of depression after stroke.