White Matter Hyperintensities and Poststroke Apathy: A Fully Automated MRI Segmentation Study

<b><i>Introduction:</i></b> Poststroke apathy (PSA) is a common neuropsychiatric disorder that may affect up to 30% of stroke patients. Despite the difficulties of investigating this condition (overlapping with depression, heterogeneity of diagnostic criteria, a small number of studies), some recent diffusion tensor imaging studies have suggested that widespread microstructural white matter (WM) disruption plays a key role in the development of PSA. Therefore, we intended to investigate this hypothesis by evaluating the relationship between WM hyperintensities (WMH) and apathy in patients with cerebrovascular disease. <b><i>Methods:</i></b> We studied patients with apathy (<i>n</i> = 7), depression (<i>n</i> = 13), comorbid apathy and depression (<i>n</i> = 13), and controls (<i>n</i> = 20), and we investigated the variables associated with the volume of WMH measured by an automated brain MRI segmentation software. <b><i>Results:</i></b> The overall prevalence of PSA was 37.7% (pure and comorbid). Patients with apathy presented a higher volume of WMH in comparison to controls. Mini-Mental State Examination (MMSE), NPI-A, and the number of cerebral microbleeds were the only variables associated with WMH. Conversely, NPI-D did not correlate to WMH. <b><i>Discussion/Conclusion:</i></b> This is an exploratory study that supports the view of PSA as a distinct syndrome from PSD mediated mainly by diffuse white matter hyperintensities, which suggests that WM disruption is an important pathway to the development of apathy in stroke patients.