Who should undergo a comprehensive cognitive assessment after a stroke? A cognitive risk score.

OBJECTIVE: To validate the ability of a specifically developed cognitive risk score to identify patients at risk of poststroke neurocognitive disorders (NCDs) who are eligible for a comprehensive cognitive assessment. METHODS: After assessing 404 patients (infarct 91.3%) in the Groupe de Réflexion pour l'Evaluation Cognitive VASCulaire (GRECogVASC) cross-sectional study with the National Institute of Neurological Disorders and Stroke-Canadian Stroke Network battery 6 months after stroke, we used multivariable logistic regression and bootstrap analyses to determine factors associated with NCDs. Independent, internally validated factors were included in a cognitive risk score. RESULTS: Cognitive impairment was present in 170 of the 320 patients with a Rankin Scale score ≥1. The backward logistic regression selected 4 factors (≥73% of the permutations): NIH Stroke Scale score on admission ≥7 (odds ratio [OR] 2.73, 95% confidence interval [CI] 1.29-4.3, p = 0.005), multiple strokes (OR 3.78, 95% CI 1.6-8, p = 0.002), adjusted Mini-Mental State Examination (MMSEadj) score ≤27 (OR 6.69, 95% CI 3.9-11.6, p = 0.0001), and Fazekas score ≥2 (OR 2.34, 95% CI 1.3-4.2, p = 0.004). The cognitive risk score computed with these 4 factors provided good calibration, discrimination (overoptimism-corrected C = 0.793), and goodness of fit (Hosmer-Lemeshow test p = 0.99). A combination of Rankin Scale score ≥1, cognitive risk score ≥1, and MMSEadj score ≥21 selected 230 (56.9%) of the 404 patients for a comprehensive assessment. This procedure yielded good sensitivity (96.5%) and moderate specificity (43%; positive predictive value 0.66, negative predictive value 0.91) and was more accurate (p ≤ 0.03 for all) than the sole use of screening tests (MMSE or Montréal Cognitive Assessment). CONCLUSION: The GRECogVASC cognitive risk score comprises 4 easily documented factors; this procedure helps to identify patients at risk of poststroke NCDs who must therefore undergo a comprehensive assessment. CLINICALTRIALSGOV IDENTIFIER: NCT01339195.

Acute Dementia After Deep Brain Stimulation in Parkinson Disease.

BACKGROUND: It is not clear whether cognitive adverse events can occur after subthalamic nuclei deep brain stimulation in Parkinson disease, and the putative mechanisms are poorly understood. CASE DESCRIPTION: We report on a rare case of a 68-year-old woman with Parkinson disease but no previous cognitive impairment. The day after deep brain stimulation of the subthalamic nuclei, the woman presented with new-onset dementia and acute, severe, persistent, global cognitive decline, prompting a diagnosis of Alzheimer disease. CONCLUSIONS: In patients seen in routine clinical practice, the simultaneous presence of several neurodegenerative diseases might not be uncommon. The assessment of mild cognitive impairment with a standardized method is highly recommended, a systematic 3-dimensional volumetric analysis of hippocampal structures should be part of the pre-deep brain stimulation evaluation, and cerebrospinal fluid biomarkers should be screened for if at least 1 of the 2 previously mentioned aspects is abnormal.