Long-Term Survival of Ischemic Stroke Patients according to Prior Cognitive Status: Dijon Stroke Registry.

INTRODUCTION: Understanding the influence of preexisting cognitive impairment on the poststroke outcome is a critical challenge in the context of current aging and growing population. This study aimed to assess long-term survival of patients with acute ischemic stroke (IS) according to their premorbid cognitive status and to identify contributing factors of death. METHODS: Patients with IS were prospectively identified among residents of Dijon, France, using a population-based registry (2013-2017). The association between case fatality at 5 years and prestroke cognitive status was assessed by multivariable Cox models adjusted for other clinical characteristics and preexisting brain damage on the initial CT scan including leukoaraiosis, old vascular brain lesions, and cortical and central brain atrophy, as well as major arterial occlusion. RESULTS: 1,049 patients were included (mean age ± SD: 76.3 ± 15.2 years old, 54% women). Case fatality rates at 5 years were 38.1% in patients without cognitive impairment, 65.9% in patients with prior mild cognitive impairment (MCI, n = 132, 12.6%), and 86.6% in patients with dementia (n = 164, 15.6%) (p < 0.001). MCI (HR = 1.39; 95% CI: 1.06-1.81, p = 0.016) and dementia (HR = 1.89; 95% CI: 1.45-2.46, p < 0.001) were both independently associated with higher case fatality after adjustment for clinical variables. The association remained significant after further adjustment for preexisting brain damage and major arterial occlusion (HR = 1.47; 95% CI: 1.10-1.98, p = 0.009, for MCI and HR = 1.90; 95% CI: 1.43-2.53, p < 0.001, for dementia) among patients with available data on the CT scan (n = 916). Factors associated with death were roughly similar across groups. CONCLUSION: This study highlighted a poor long-term survival of IS patients with preexisting cognitive impairment, independently of other contributing factors of death. It is critical to better understand the trajectory of IS patients with preexisting cognitive impairment and to identify prognostic markers to guide clinicians in their management strategies.

Pre-existing brain damage and association between severity and prior cognitive impairment in ischemic stroke patients.

BACKGROUND: We evaluated whether pre-existing brain damage may explain greater severity in cognitively-impaired patients with ischemic stroke (IS). METHODS: IS patients were retrieved from the population-based registry of Dijon, France. Pre-existing damage (leukoaraiosis, old vascular brain lesions, cortical and central brain atrophy) was assessed on initial CT-scan. Association between prestroke cognitive status defined as no impairment, mild cognitive impairment (MCI), or dementia, and clinical severity at IS onset assessed with the NIHSS score was evaluated using ordinal regression analysis. Mediation analysis was performed to assess pre-existing brain lesions as mediators of the relationship between cognitive status and severity. RESULTS: Among the 916 included patients (mean age 76.8 ± 15.0 years, 54.3% women), those with pre-existing MCI (n = 115, median NIHSS [IQR]: 6 [2-15]) or dementia (n = 147, median NIHSS: 6 [3-15]) had a greater severity than patients without (n = 654, median NIHSS: 3 [1-9]) in univariate analysis (OR=1.69; 95% CI: 1.18-2.42, p = 0.004, and OR=2.06; 95% CI: 1.49-2.84, p < 0.001, respectively). Old cortical lesion (OR=1.53, p = 0.002), central atrophy (OR=1.41, p = 0.005), cortical atrophy (OR=1.90, p < 0.001) and moderate (OR=1.41, p = 0.005) or severe (OR=1.84, p = 0.002) leukoaraiosis were also associated with greater severity. After adjustments, pre-existing MCI (OR=1.52; 95% CI: 1.03-2.26, p = 0.037) or dementia (OR=1.94; 95% CI: 1.32-2.86, p = 0.001) remained associated with higher severity at IS onset, independently of confounding factors including imaging variables. Association between cognitive impairment and severity was not mediated by pre-existing visible brain damages. CONCLUSION: Impaired brain ischemic tolerance in IS patients with prior cognitive impairment could involve other mechanisms than pre-existing visible brain damage.

Atrial fibrillation and preexisting cognitive impairment in ischemic stroke patients: Dijon Stroke Registry.

BACKGROUND: Atrial Fibrillation (AF) is a common cause of ischemic stroke (IS), and is associated with cognitive impairment in the general population. We aimed to compare the prevalence of preexisting cognitive impairment between IS patients with and without AF, and to assess whether prior brain damage could contribute to the observed differences. METHODS: Patients with acute IS were prospectively identified from the population-based Dijon Stroke Registry, France. Patients who had a CT-scan as brain imaging modality were included in this analysis to assess the presence of preexisting leukoaraiosis, old vascular brain lesions, and cerebral atrophy. Characteristics of patients including prior-to-stroke cognitive status (normal cognition, mild cognitive impairment (MCI), or dementia) were compared between those with and without AF. RESULTS: Among 916 IS patients, 288 (31.4 %) had AF, of whom 88 had newly diagnosed AF. AF patients had more frequent prior MCI (17.8 % versus 10.2 %) or dementia (22.4 % versus 13.1 %) (p = 0.001), vascular risk factors, and preexisting brain damage. In unadjusted model, preexisting cognitive impairment was associated with AF (OR=2.24; 95 % CI: 1.49-3.37, p < 0.001 for MCI; OR=2.20; 95 % CI: 1.52-3.18, p < 0.001 for dementia). After adjustment for clinical and imaging variables, preexisting mild cognitive impairment (OR=1.87; 95 % CI: 1.06-3.32, p = 0.032) and dementia (OR=1.98; 95 % CI: 1.15-3.40, p = 0.013) were independently associated with AF. CONCLUSION: AF is a common condition in IS patients and is associated with preexisting cognitive impairment. Brain lesions visible on imaging did not seem to fully account for this association that may involve other mechanisms yet to be elucidated.