Nerve excitability test and lead toxicity: a case-control study.

BACKGROUND: Although conventional electrophysiological parameters have been proposed as clinical indicators for monitoring lead neuropathies, their correlations with blood lead level are weak. In this study, we investigated the applicability of nerve excitability tests (NETs) to evaluate lead intoxication. METHODS: Fourteen workers who were exposed to lead with an elevated blood level ranging from 17.8 to 64.9 µg/dL and 20 healthy controls with similar ages and body heights were enrolled. Both workers and controls underwent nerve conduction studies (NCSs), motor evoked potentials (MEPs) with transcranial magnetic stimulation (TMS), and NETs. RESULTS: NCSs showed prolonged distal latencies and decreased motor nerve conduction velocity of median nerves in the workers but without significant correlation to blood lead level (BLL). Significantly prolonged MEP latency was observed in the workers (+ 6 ms). NETs demonstrated hyperpolarized resting membrane potentials in stimulus-response curves and changes in the property of potassium channels under a hyperpolarized current in threshold electrotonus, implying that lead hyperpolarized nerves by interfering with potassium channels. NETs also showed a better correlation with BLL than conventional electrophysiological parameters. CONCLUSIONS: Axonal hyperpolarization and central conduction delay are more apparently reflecting elevated BLL than NCS. NET may have the potential for early detection of lead neuropathy.

The Association between Ankle-Brachial Index/Pulse Wave Velocity and Cerebral Large and Small Vessel Diseases in Stroke Patients.

(1) Background: The study investigated whether the ankle-brachial index (ABI) and pulse wave velocity (baPWV) could reflect the severity of small vessel disease (SVD) and large artery atherosclerosis (LAA). (2) Methods: A total of 956 consecutive patients diagnosed with ischemic stroke were prospectively enrolled from July 2016 to December 2017. SVD severity and LAA stenosis grades were evaluated via magnetic resonance imaging and carotid duplex ultrasonography. Correlation coefficients were calculated between the ABI/baPWV and measurement values. Multinomial logistic regression analysis was performed to determine predictive potential. (3) Results: Among the 820 patients included in the final analysis, the stenosis grade of extracranial and intracranial vessels was inversely correlated with the ABI (p < 0.001, respectively) and positively correlated with the baPWV (p < 0.001 and p = 0.004, respectively). Abnormal ABI, not baPWV, independently predicted the presence of moderate (adjusted odds ratio, aOR: 2.18, 95% CI: 1.31-3.63) to severe (aOR: 5.59, 95% CI: 2.21-14.13) extracranial vessel stenosis and intracranial vessel stenosis (aOR: 1.89, 95% CI: 1.15-3.11). Neither the ABI nor baPWV was independently associated with SVD severity. (4) Conclusions: ABI is better than baPWV in screening for and identifying the existence of cerebral large vessel disease, but neither test is a good predictor of cerebral SVD severity.

Cognitive Function Deterioration After Cardiopulmonary Bypass: Can Intraoperative Optimal Cerebral Regional Tissue Oxygen Saturation Predict Postoperative Cognitive Function?

OBJECTIVE: Cognitive impairment is a common neurologic complication after cardiac surgery with cardiopulmonary bypass (CPB). This study evaluated postoperative cognitive function to determine predictors of cognitive dysfunction, including intraoperative cerebral regional tissue oxygen saturation (rSO2). DESIGN: A prospective observational cohort study. SETTING: At a single academic tertiary-care center. PARTICIPANTS: A total of 60 adults undergoing cardiac surgery with CPB from January to August 2021. INTERVENTIONS: None. MEASUREMENTS AND MAIN RESULTS: All patients underwent Mini-Mental State Examination (MMSE) and quantified electroencephalography (qEEG) 1 day before cardiac surgery, 7 days postoperatively (POD7), and POD60. Intraoperative cerebral rSO2 was monitored continuously. For MMSE, no significant decrease in MMSE score was found on POD7 versus preoperatively (p = 0.09), but POD60 scores showed significant improvement compared with both preoperative (p = 0.02) and POD7 scores (p < 0.001). On qEEG, relative theta power on POD7 was increased versus preoperatively (p < 0.001), but it was decreased on POD60 (POD7 versus POD60, p < 0.001), and was close to preoperative data (p > 0.99). Baseline rSO2 was an independent factor for postoperative MMSE. Both baseline and mean rSO2 showed a significant influence in postoperative relative theta activity, whereas mean rSO2 was the only predictor for the theta-gamma ratio (p = 0.04). CONCLUSIONS: The MMSE in patients undergoing CPB declined at POD7 and recovered by POD60. Lower baseline rSO2 indicated a higher potential for MMSE decline at POD60. Inferior intraoperative mean rSO2 was related to higher postoperative relative theta activity and theta-gamma ratio, implying subclinical or further cognitive impairment.

Investigating the interaction between neuropsychiatry features and daily activities on social function in patients with Parkinson's disease with mild cognitive impairment.

BACKGROUND: Social functioning is crucial for daily living and is an essential indicator of dementia in patients with Parkinson's disease. The pattern of social functioning in patients with Parkinson's disease without dementia (i.e. those who are cognitively intact or have mild cognitive impairment (PD-MCI)) and its determinants are unclear. AIMS: In exploring the heterogeneity of social functioning among patients with Parkinson's disease-associated dementia, we determined the optimal cut-off score of the Parkinson's Disease Social Functioning Scale (PDSFS) for patients with PD-MCI, and the variables influencing patients' social functioning. METHOD: A total of 302 participants underwent the Mini-Mental State Examination (MMSE) and PDSFS; 120 patients with Parkinson's disease completed the measurements (MMSE, Activities of Daily Living Scale and Neuropsychiatric Inventory). Group comparisons, receiver operating characteristic curves, Spearman correlation and multiple and hierarchical regression analyses were conducted. RESULTS: The PD-MCI group scored the lowest on the PDSFS (F = 10.10, P < 0.001). The PDSFS cut-off score was 53 (area under the curve 0.700, sensitivity 0.800, specificity 0.534). The MMSE (ß = 0.293, P = 0.002), Activities of Daily Living Scale (ß = 0.189, P = 0.028) and Neuropsychiatric Inventory (ß = -0.216, P = 0.005) scores predicted the PDSFS score. Further, there was an interaction effect between the Activities of Daily Living Scale and Neuropsychiatric Inventory scores on the PDSFS score (ß = 0.305, P < 0.001). CONCLUSIONS: We determined a PDSFS cut-off score for detecting PD-MCI and found that patients with PD-MCI have social dysfunction. Future research should focus on the effects of neuropsychiatry symptoms and activities of daily living on social functioning, and tailor the intervention programme for patients with Parkinson's disease.

A New Instrument Combines Cognitive and Social Functioning Items for Detecting Mild Cognitive Impairment and Dementia in Parkinson's Disease.

Background: The commonly used screening tests for Parkinson's disease (PD) are the Montreal Cognitive Assessment (MoCA) and Mini-Mental State Examination (MMSE), both of which only focus on cognitive function. A composite assessment that considers both cognitive and social dysfunction in PD would be helpful in detecting mild cognitive impairment (MCI) and PD dementia (PDD). Objective: We aimed to simplify the commonly used tools and combine cognitive and social functioning tests to detect early MCI and PDD. Materials and Methods: A total of 166 participants (84 PD patients and 82 healthy) were recruited who completed the MMSE, MoCA, PD social functioning scale (PDSFS), clock drawing test, activities of daily living, comprehensive neuropsychological assessment (e.g., executive, attention, language, memory, and visuospatial functions), and movement disorder society (MDS)-unified PD rating scale. According to the MDS diagnostic criteria, the patients were grouped into PD-nonMCI, PD-MCI, or PDD. Results: To detect PD-MCI, the optimal cut-off scores for the simplified MoCA and the combined test were 9 and 35. The discrimination values measured by the area under the receiver operating characteristic curve (AUC) of the two tests were 0.767 (p < 0.001) and 0.790 (p < 0.001). When the simplified MoCA was 7 or the combined test 30, the patients would be classified as having PDD. The AUCs of the two tests were 0.846 (p < 0.001) and 0.794 (p = 0.003). Conclusion: We suggest considering both cognitive and social functions when detecting PD-MCI and PDD.

Hypomimia May Influence the Facial Emotion Recognition Ability in Patients with Parkinson's Disease.

BACKGROUND: Hypomimia is a clinical feature of Parkinson's disease (PD). Based on the embodied simulation theory, the impairment of facial mimicry may worsen facial emotion recognition; however, the empirical results are inconclusive. OBJECTIVE: We aimed to explore the worsening of emotion recognition by hypomimia. We further explored the relationship between the hypomimia, emotion recognition, and social functioning. METHODS: A total of 114 participants were recruited. The patients with PD and normal controls (NCs) were matched for demographic characteristics. All the participants completed the Mini-Mental State Examination and the Chinese Multi-modalities Emotion Recognition Test. In addition to the above tests, the patients were assessed with the Movement Disorder Society-Unified Parkinson's Disease Rating Scale and Parkinson's Disease Social Functioning Scale (PDSFS). RESULTS: Patients with PD with hypomimia had worse recognition of disgust than NCs (p = 0.018). The severity of hypomimia was predictive of the recognition of disgust (ß= -0.275, p = 0.028). Facial emotion recognition was predictive of the PDSFS score of PD patients (ß= 0.433, p = 0.001). We also found that recognizing disgust could mediate the relationship between hypomimia and the PDSFS score (ß= 0.264, p = 0.045). CONCLUSION: Patients with hypomimia had the worst disgust facial recognition. Hypomimia may affect the social function of PD patients, which is related to recognizing the expression of disgust. Emotion recognition training may improve the social function of patients with PD.

Using Artificial Neural Network to Discriminate Parkinson's Disease from Other Parkinsonisms by Focusing on Putamen of Dopamine Transporter SPECT Images.

BACKGROUND: The challenge of differentiating, at an early stage, Parkinson's disease from parkinsonism caused by other disorders remains unsolved. We proposed using an artificial neural network (ANN) to process images of dopamine transporter single-photon emission computed tomography (DAT-SPECT). METHODS: Abnormal DAT-SPECT images of subjects with Parkinson's disease and parkinsonism caused by other disorders were divided into training and test sets. Striatal regions of the images were segmented by using an active contour model and were used as the data to perform transfer learning on a pre-trained ANN to discriminate Parkinson's disease from parkinsonism caused by other disorders. A support vector machine trained using parameters of semi-quantitative measurements including specific binding ratio and asymmetry index was used for comparison. RESULTS: The predictive accuracy of the ANN classifier (86%) was higher than that of the support vector machine classifier (68%). The sensitivity and specificity of the ANN classifier in predicting Parkinson's disease were 81.8% and 88.6%, respectively. CONCLUSIONS: The ANN classifier outperformed classical biomarkers in differentiating Parkinson's disease from parkinsonism caused by other disorders. This classifier can be readily included into standalone computer software for clinical application.

The Impact of Antiplatelet Use on the Risk of Intracerebral Hemorrhage in Patients with Alzheimer's Disease: A Nationwide Cohort Study.

BACKGROUND: Antiplatelet use on the risk of intracerebral hemorrhage (ICH) in patients with Alzheimer's disease (AD) has not yet been completely elucidated. OBJECTIVE: This large epidemiologic study aims to estimate the risk of ICH in AD patients treated with antiplatelet therapy (APT). METHODS: Using data from Taiwan's National Health Insurance Research Database, ICH risk in APT-treated AD patients with a validated diagnosis (N = 824) was determined. AD without APT and non-AD with and without APT comparison cohorts were selected. To adjust for confounders and competing risk of death, inverse probability of treatment weighting using propensity scores and competing risks regression (CRR) were applied. Cox proportional hazards regression analysis estimated ICH risk in all cohorts comparing with non-AD without APT. RESULTS: Among the 824 AD patients with APT, 79.6% were prescribed aspirin. ICH incidence rates in the AD (with/without APT) and non-AD (with/without APT) cohorts were 2.88/2.70 and 2.24/1.20 per 1,000 person-years, respectively. Overall, AD with (adjusted hazards ratio (aHR), 2.29; 95% CI, 1.19-4.38) and without (aHR, 1.97; 95% CI, 1.08-3.61) APT and non-AD with APT (aHR, 1.80; 95% CI, 1.34-2.42) were at a higher risk and had elevated subdistribution HR obtained from CRR than non-AD without APT controls. However, the risk was comparable between the AD cohorts with and without APT (HR, 1.16; 95% CI, 0.51-2.66). CONCLUSIONS: Our study indicated both the APT and non-APT users in AD population yielded higher ICH risks. However, whether APT use potentiate the risk of ICH in AD patients may warrant further evaluation.