Cerebral microbleeds and symptom severity of post-stroke depression: a magnetic resonance imaging study

Background Cerebral microbleeds (CMBs) are common in stroke survivors, although their clinical significance in the development of psychiatric conditions following stroke remains unknown. This study examines the association between post-stroke depression (PSD) symptom severity and CMBs. Methods Amongst the 4088 patients with acute ischemic stroke who had been admitted to the acute stroke unit of a university-affiliated regional hospital in Hong Kong, between December 2004 and May 2009, 994 patients were recruited. A psychiatrist administered the Structural Clinical Interview for DSM-IV to all 994 patients and made a diagnosis of PSD three months after the index stroke. PSD symptom severity was assessed with the 15-item Geriatric Depression Scale (GDS). Seventy-eight patients were found to have PSD. The presence and location of CMBs were evaluated with magnetic resonance imaging (MRI). Results Seventy-eight patients (7.8%) had PSD. CMBs were identified in 20 PSD patients. Relative to the no-CMB group, the mean GDS score of patients with lobar CMBs was significantly higher (12.6±2.6 versus 10.4±2.5, p=0.01 after adjusting for age, sex, global cognitive functions, neurological deficits and white matter hyperintensities). Limitations Patients with more severe stroke, those who died before the three-month follow-up and those who became depressed later were excluded, as were those unable to give their consent due to dementia or aphasia. These selection biases may limit the generalizability of the findings. Conclusions The results suggest that lobar CMBs may contribute to PSD symptom severity. The importance of CMBs in the pathogenesis of other psychiatric disorders in stroke survivors and other patient populations warrants further investigation.