Journal of the Neurological Sciences issue 452 now available

Neurological disorders and disability in Pakistan: A cross-sectional multicenter study

Wasay et al.

Published online: July 30, 2023

The aim of this study is to identify frequencies of various neurological disorders (NDs) and associated disability in patients attending neurologic clinics in rural and urban centers in Pakistan.

This is an observational study conducted in 39 neurological centers in both rural and urban areas, public and private health sectors all over Pakistan. This study was conducted between august 2017 to December 2019.

A total of 28,845 adults were enrolled. Mean age of the study participants was 46.2 ± 17.2 years, 15,252 (52.9%) were men and 13,593 (47.1%) were women. Most common comorbid medical condition was hypertension 7622(26.4%) followed by Diabetes 3409(11.8%). Among neurological diagnoses, vascular diseases (20%) were the most common followed by Headache disorders (18.6%), Epilepsy (12.5%), nerve and root diseases (12.4%), Psychiatric diseases (10%), Dementias (8%) and movement disorders (7.9%). Half of the patients 15,503(53.7%) had no neurological disability, while minor disability was present in 10,442(36.2%) of cases. Moderate to severe disability was present in 2876(10%) cases. Headache disorders, psychiatric diseases, muscle pain/muscle related disorders and demyelinating diseases were more common in women. Vascular diseases, movement disorders and Dementias were more common in 46 years and above age group whereas headache disorders, Epilepsy and Psychiatric disorders were more prevalent in <46 years age groups.

Vascular diseases are the most common presentation of patients in neurology clinics followed by headache disorders and epilepsies. Minor disability was present in 36% while moderate to severe disability was present in 10% cases.

Bilateral globus pallidus internus (GPi) deep brain stimulation for cervical dystonia: Effects on motor and non-motor symptoms within 5 years follow

Khanom et al.

Published online: July 31, 2023

Cervical Dystonia ("CD") is a movement disorder characterised by sustained muscle contractions in the neck, causing involuntary posturing. Deep brain stimulation ("DBS") of the globus pallidal internus (GPi) is advanced treatment for pharmaco-refractory patients. As CD is a rare disease, cohort studies are often limited to patients of heterogenous disease profile, small sample size or short follow-up. This study firstly aimed to measure the efficacy of GPi-DBS on motor and non-motor symptoms of CD. A secondary aim was to evaluate if clinical factors – such as age, disease duration and baseline disease severity – influence variability of motor outcomes.

We concluded that GPi-DBS is an effective treatment for motor symptoms and pain in CD. There was limited effect on mood and QoL, and no clinical predictive factors of outcome were identified.

NOTCH3 C201R variant causes cerebral autosomal dominant arteriopathy with subcortical infarcts and leukoencephalopathy (CADASIL) that can be confused with early-onset Alzheimer's disease

Korvatska et al.

Published online: August 7, 2023

NOTCH3 is the causative gene for autosomal dominant cerebral arteriopathy with subcortical infarctions and leukoencephalopathy (CADASIL) which is associated with both stroke and dementia. When CADASIL presents primarily as dementia it can be difficult to distinguish from Alzheimer's disease (AD) at both the clinical and neuropathological levels.

We performed exome sequencing of several affected individuals from a large family affected with AD. PCR amplification and direct Sanger sequencing were used to verify variants detected by exome analysis and to screen family members at-risk to carry those variants. Neuropathologic brain evaluation by immunohistochemistry and MRI were performed for the carriers of the NOTCH3 variant.

Our findings, together with other reported pathogenic missense variants of the C201 codon in NOTCH3, support the role of cysteine 201 as a mutation hotspot for CADASIL and highlight the genetic complexity both clinically and pathologically of AD and related dementia.

Upregulation of the parietal cortex improves freezing of gait in Parkinson's disease

Potvin-Desrochers et al.

Published online: August 18, 2023

The posterior parietal cortex (PPC) is a key brain area for visuospatial processing and locomotion. It has been repetitively shown to be involved in the neural correlates of freezing of gait (FOG), a common symptom of Parkinson's disease (PD). However, current neuroimaging modalities do not allow to precisely determine the role of the PPC during real FOG episodes.

The purpose of this study was to modulate the PPC cortical excitability using repetitive transcranial magnetic stimulation (rTMS) to determine whether the PPC contributes to FOG or compensates for dysfunctional neural networks to reduce FOG.

Increasing PPC excitability resulted in significantly fewer freezing episodes and percent time frozen during a FOG-provoking task. This reduction in FOG most likely emerged from the trend in PPC inhibiting the lower leg motor cortex excitability.

Our results suggest that the recruitment of the PPC is linked to less FOG, providing support for the beneficial role of the PPC upregulation in preventing FOG. This could potentially be linked to a reduction of the cortical input burden on the basal ganglia prior to FOG. Excitatory rTMS interventions targeting the PPC may have the potential to reduce FOG.