Rate of progression of mild cognitive impairment to dementia – meta‐analysis of 41 robust inception cohort studies

Objective: To quantify the risk of developing dementia in those with mild cognitive impairment (MCI). Method: Meta‐analysis of inception cohort studies. Results: Forty‐one robust cohort studies were identified. To avoid heterogeneity clinical studies, population studies and clinical trials were analysed separately. Using Mayo defined MCI at baseline and adjusting for sample size, the cumulative proportion who progressed to dementia, to Alzheimer’s disease (AD) and to vascular dementia (VaD) was 39.2%, 33.6% and 6.2%, respectively in specialist settings and 21.9%, 28.9% and 5.2%, respectively in population studies. The adjusted annual conversion rate (ACR) from Mayo defined MCI to dementia, AD and VaD was 9.6%, 8.1% and 1.9%, respectively in specialist clinical settings and 4.9%, 6.8% and 1.6% in community studies. Figures from non‐Mayo defined MCI and clinical trials are also reported. Conclusion: The ACR is approximately 5–10% and most people with MCI will not progress to dementia even after 10 years of follow‐up.     

“Recumbent” gait: Relationship to the phenotype of “astasia‐abasia”?

Psychogenic gait disorders can present in many different ways. Among patients with a pure psychogenic gait disorder, buckling of the knee is the most common feature, followed by astasia-abasia. Here, we describe one such patient with a very unusual gait disturbance that might be regarded as a variant of astasia-abasia. The patient characteristics are described and discussed in a historical context.     

The “neuro” of neuroblastoma: Neuroblastoma as a neurodevelopmental disorder

Neuroblastoma is a childhood cancer derived from cells of neural crest origin. The hallmarks of its enigmatic character include its propensity for spontaneous regression under some circumstances and its association with paraneoplastic opsoclonus, myoclonus, and ataxia. The neurodevelopmental underpinnings of its origins may provide important clues for development of novel therapeutic and preventive agents for this frequently fatal malignancy and for the associated paraneoplastic syndromes. Ann Neurol 2016;80:13–23     

Depression in patients with mild cognitive impairment increases the risk of developing dementia of Alzheimer type: a prospective cohort study

BACKGROUND: Mild cognitive impairment has been regarded as a precursor to dementia of Alzheimer type, but not all patients with mild cognitive impairment develop dementia. OBJECTIVE: To determine whether depression may increase the risk of developing dementia. SETTING: The outpatient clinics of a community general hospital. DESIGN: Prospective cohort study. METHODS: A cohort of 114 patients with amnestic mild cognitive impairment was followed up for a mean period of 3 years. At baseline, the patients underwent memory tests, the Spanish version of the Mini-Mental State Examination, a verbal fluency test, the Geriatric Depression Scale, and the Clinical Dementia Rating Scale for staging purposes. Psychiatric examination for depression was based on structured interview and Diagnostic and Statistical Manual of Mental Disorder, Fourth Edition criteria. We also carried out either computed tomography or magnetic resonance imaging of the brain. MAIN OUTCOME MEASURES: We carried out periodic evaluations based on the Mini-Mental State Examination, verbal fluency test, Geriatric Depression Scale, Blessed Dementia Rating Scale, and Clinical Dementia Rating Scale. The end point was the development of probable Alzheimer disease according to the criteria of the National Institute of Neurological and Communicative Disorders and Stroke-Alzheimer's Disease and Related Disorders Association. RESULTS: Depression was observed in 41 patients (36%) at baseline. After a mean period of 3 years, 59 patients (51.7%) developed dementia of Alzheimer type, and 6 died. Of the depressed patients, 35 (85%) developed dementia in comparison with 24 (32%) of the nondepressed patients (relative risk, 2.6; 95% confidence interval, 1.8-3.6). The survival analysis also showed that depressed patients developed dementia earlier than the nondepressed. Most patients with depression at baseline exhibited a poor response to antidepressants. CONCLUSIONS: We conclude that patients with mild cognitive impairment and depression are at more than twice the risk of developing dementia of Alzheimer type as those without depression. Patients with a poor response to antidepressants are at an especially increased risk of developing dementia.