Brain changes correlate with neuropathic pain in patients with neuromyelitis optica spectrum disorders.

BACKGROUND: Neuropathic pain (NP) is a highly disturbing sensory experience in patients with neuromyelitis optica spectrum disorders (NMOSD). However, the brain changes in NMOSD patients with NP have rarely been studied. OBJECTIVE: The aim of the cross-sectional and follow-up longitudinal study was to investigate the brain changes in NMOSD patients with NP. METHODS: In the cross-sectional study, comparisons were performed between groups with NP (W-NP) and without NP (Wo-NP), and age, sex and years of education were adjusted. We compared the voxel-wise whole-brain gray matter (GM) volume, cortical thickness (CT), cortical surface area (CSA) and local gyrification index (LGI). Probabilistic tractography started from regions with significant between-group differences in GM volume, CT, CSA and LGI. We also compared fractional anisotropy (FA), mean diffusivity (MD), radial diffusivity (RD) and axial diffusivity (AD) of the white matter (WM) skeleton using Tract-Based Spatial Statistics (TBSS). In the longitudinal study, the patients were followed for 2.0±0.0 years and underwent the same imaging scanning as the cross-sectional study. Changes of the CT, CSA, LGI and WM were obtained. RESULTS: Patients in the W-NP group were older than those in the Wo-NP group and showed significantly reduced LGI of the left temporal lobe and adjacent regions(regions of interest, ROIs), which participated in neuropathic pain processing, possibly by emotion and attention control. Probabilistic tractography started from ROIs, and the generated WM tracts showed decreased MD and RD in the W-NP group compared to the Wo-NP group. Using TBSS, both MD and RD decreased in extensive WM skeleton in the right hemisphere of the patients in the W-NP group. Additionally, in the follow-up longitudinal study, compared with patients in the Wo-NP group, patients in the W-NP group showed lower mean reduction rates of LGI of ROIs, and less increase of FA and more increases of MD, AD and RD in the extensive WM skeleton. CONCLUSIONS: These findings support the hypothesis that brain changes might correlate with NP in NMOSD patients and predict the changes related to NP over time.

Hearing loss is associated with increased stroke risk in the Dongfeng-Tongji Cohort.

BACKGROUND AND AIMS: The evidence concerning the association between hearing loss and stroke is limited. We aimed to investigate the association of hearing loss with risk of stroke and its subtypes among the middle-aged and older Chinese population. METHODS: We included 19,238 participants aged 64.6 years from the Dongfeng-Tongji Cohort in 2013. Hearing loss was classified into normal, mild, moderate, severe or greater levels by the pure tone average at speech frequency and high frequency, respectively. We calculated the odds ratios of hearing loss and stroke by logistic regression models. RESULTS: With the increase of hearing loss level, the prevalence risk of stroke has gradually increased. Compared with normal hearing, participants having severe or greater hearing loss had a higher stroke risk of 76% and 39% at speech frequency and at high frequency, respectively. Similarly, individuals with severe or greater hearing loss had an increased risk of ischemic stroke of 69% and 52% at speech frequency and high frequency, respectively; while severe or greater hearing loss was associated with about a 2-fold risk of hemorrhagic stroke than normal hearing only at speech frequency. Stratified analysis suggested that some high cardiovascular risk participants such as male, age ≥65, exposed to occupational noise, smoker and with diabetes, hypertension or hyperlipidemia had higher risk of stroke. Furthermore, severe or greater hearing loss combined with age, diabetes, hypertension and hyperlipidemia had joint effects on stroke. CONCLUSIONS: The results have suggested a dose-response relationship between hearing loss and stroke risk in middle-aged and older adults.