Cognitive Impairment and Psychiatric Morbidity in Chinese Stroke Patients: Clinical and Imaging Characterization.

摘要

The first study reported in this thesis involved 328 Chinese ischemic stroke patients who were administered a series of neuropsychological tests covering seven domains three months after stroke. Two hundred and fifty-six of these patients were followed-up for one year. Volumetry of the infarcts, WMLs, and hippocampus atrophy on magnetic resonance imaging (MRI) was conducted. The prevalence of cognitive impairment was 54.9% at baseline and 52.4% at the one-year follow-up, although most of the patients (85.5%) remained cognitively stable. The evolution of cognitive impairment no dementia (CIND) at the one-year follow-up was bidirectional, with 11.2% progressing to dementia and 21.0% reverting to cognitive intact. WMLs volume rather than hippocampal volume was a significant predictor of cognitive impairment, cognitive decline, and delayed dementia. WMLs also had an independent effect on executive function, attention, visual memory, visuoconstruction, and visuomotor speed.;Poststroke depression (PSD) is the most common form of poststroke psychiatric morbidity. Small subcortical infarcts (SSIs) can result from small vessel disease (SVD) and large artery disease (LAD). No study has yet explored PSD in different etiological types of SSIs. To address this gap, 127 patients with SSIs resulting from LAD or SVD were examined. PSD was evaluated with the Geriatric Depression Scale (GDS) three months after stroke. The LAD group had a significantly higher frequency of PSD, and LAD was found to be a significant independent risk factor for PSD. This study suggests that cerebral blood perfusion may play an important role in PSD.;Post-stroke emotional lability (PSEL) is a distressing and embarrassing complaint among stroke survivors. Lesions located in various cortical and subcortical areas are thought to be involved in the pathophysiology of PSEL.The clinical significance of microbleeds (MBs) in the development of psychiatric conditions following stroke is unknown. We carried out a study to examine the association between PSEL and MBs in 519 Chinese patients with acute ischemic stroke admitted consecutively. PSEL was evaluated three months after the index stroke, and the number and location of MBs were evaluated with MRI. According to Kim's criteria, 74 (14.3%) of the patients had PSEL. Our results suggest that MBs in the thalamus may play a role in the development of PSEL. The importance of MBs in PSEL and other psychiatric conditions in stroke survivors warrants further investigation.;Frontal lobe atrophy (FLA) is associated with late-life depression and cognitive impairment, although the pathogenesis of FLA in stroke is unclear. In an aim to ascertain whether FLA is affected by WMLs, we analyzed the MRIs of 471 Chinese ischemic stroke patients. Lobar atrophy was defined by a widely-used visual rating scale. WML severity was rated using the Fazekas scale. There was no correlation between PVH and DWMH and temporal and parietal atrophy. The results of this study suggest that FLA in ischemic stroke may be associated with SVD.;This thesis investigates the clinical and imaging characterization of cognitive impairment and psychiatric morbidity in Chinese stroke patients. The conclusions of the studies reported herein can be summarized as follows. (1) The prevalence of cognitive impairment is high among Chinese poststroke patients, but most remain cognitively stable at one year after stroke; WMLs rather than hippocampal atrophy predict cognitive impairment, longitudinal cognitive decline, and delayed dementia; (2) DLPFC atrophy is correlated with poor verbal fluency in elderly women with stroke, but not in their male counterparts; (3) LAD may be associated with PSD in patients with small subcortical infarcts; (4) MBs in the thalamus are associated with PSEL; (5) frontal lobe infarction and diabetes may be risk factors of insomnia symptoms in stroke patients; and (6) FLA in ischemic stroke may be associated with SVD. (Abstract shortened by UMI.)