Preparing Malaysia for Population Aging through the Advanced Memory and Cognitive Service in Hospital Universiti Sains Malaysia

Improving healthcare and living conditions has led to an increase in life expectancies and challenges of population aging in Malaysia. The Advanced Memory and Cognitive Service builds on integrated healthcare among multidisciplinary specialists to provide holistic and patient-centred healthcare. The service treats older adults experiencing neurocognitive impairment as well as young individuals with complex neurocognitive disorders and thoroughly screens asymptomatic individuals at high risk of developing neurocognitive disorders. This early intervention strategy is a preventive effort in the hope of reducing disease burden and improving quality of life to prepare Malaysia for the forthcoming population aging.

The Brain-Gut Clinic in Hospital Universiti Sains Malaysia: Pioneering New Service to Advance Neuro-Gastroenterology and Motility in Malaysia

Neurogastroenterology and motility is a new but advanced subspecialty within gasteroenterology that cater to difficult, persistent and refractory gut-brain symptoms. Hospital USM has the country's first and new state-of-the art motility lab that was recently launched on the 25 May 2023, and is covered in nationwide media. Another first is the Brain-Gut Clinic, established on the 16 November 2022. The clinic is a new concept that builds on unique multiple disciplines in relation to the gut-brain axis. It is hoped that there will be more awareness on the existence of neurogastroenterology and motility among doctors and community, and that more research can be forthcoming to reduce the disease burden.

Disruption of white matter integrity and its relationship with cognitive function in non-severe traumatic brain injury

Background

Impairment in cognitive function is a recognized outcome of traumatic brain injury (TBI). However, the degree of impairment has variable relationship with TBI severity and time post injury. The underlying pathology is often due to diffuse axonal injury that has been found even in mild TBI. In this study, we examine the state of white matter putative connectivity in patients with non-severe TBI in the subacute phase, i.e., within 10 weeks of injury and determine its relationship with neuropsychological scores.

Methods

We conducted a case-control prospective study involving 11 male adult patients with non-severe TBI and an age-matched control group of 11 adult male volunteers. Diffusion MRI scanning and neuropsychological tests were administered within 10 weeks post injury. The difference in fractional anisotropy (FA) values between the patient and control groups was examined using tract-based spatial statistics. The FA values that were significantly different between patients and controls were then correlated with neuropsychological tests in the patient group.

Results

Several clusters with peak voxels of significant FA reductions (p < 0.05) in the white matter skeleton were seen in patients compared to the control group. These clusters were located in the superior fronto-occipital fasciculus, superior longitudinal fasciculus, uncinate fasciculus, and cingulum, as well as white matter fibers in the area of genu of corpus callosum, anterior corona radiata, superior corona radiata, anterior thalamic radiation and part of inferior frontal gyrus. Mean global FA magnitude correlated significantly with MAVLT immediate recall scores while matrix reasoning scores correlated positively with FA values in the area of right superior fronto-occipital fasciculus and left anterior corona radiata.

Conclusion

The non-severe TBI patients had abnormally reduced FA values in multiple regions compared to controls that correlated with several measures of executive function during the sub-acute phase of TBI.

Harmonized-Multinational qEEG norms (HarMNqEEG)

This paper extends frequency domain quantitative electroencephalography (qEEG) methods pursuing higher sensitivity to detect Brain Developmental Disorders. Prior qEEG work lacked integration of cross-spectral information omitting important functional connectivity descriptors. Lack of geographical diversity precluded accounting for site-specific variance, increasing qEEG nuisance variance. We ameliorate these weaknesses. (i) Create lifespan Riemannian multinational qEEG norms for cross-spectral tensors. These norms result from the HarMNqEEG project fostered by the Global Brain Consortium. We calculate the norms with data from 9 countries, 12 devices, and 14 studies, including 1564 subjects. Instead of raw data, only anonymized metadata and EEG cross-spectral tensors were shared. After visual and automatic quality control, developmental equations for the mean and standard deviation of qEEG traditional and Riemannian DPs were calculated using additive mixed-effects models. We demonstrate qEEG "batch effects" and provide methods to calculate harmonized z-scores. (ii) We also show that harmonized Riemannian norms produce z-scores with increased diagnostic accuracy predicting brain dysfunction produced by malnutrition in the first year of life and detecting COVID induced brain dysfunction. (iii) We offer open code and data to calculate different individual z-scores from the HarMNqEEG dataset. These results contribute to developing bias-free, low-cost neuroimaging technologies applicable in various health settings.

Alteration in the Functional Organization of the Default Mode Network Following Closed Non-severe Traumatic Brain Injury

The debilitating effect of traumatic brain injury (TBI) extends years after the initial injury and hampers the recovery process and quality of life. In this study, we explore the functional reorganization of the default mode network (DMN) of those affected with non-severe TBI. Traumatic brain injury (TBI) is a wide-spectrum disease that has heterogeneous effects on its victims and impacts everyday functioning. The functional disruption of the default mode network (DMN) after TBI has been established, but its link to causal effective connectivity remains to be explored. This study investigated the differences in the DMN between healthy participants and mild and moderate TBI, in terms of functional and effective connectivity using resting-state functional magnetic resonance imaging (fMRI). Nineteen non-severe TBI (mean age 30.84 ± 14.56) and twenty-two healthy (HC; mean age 27.23 ± 6.32) participants were recruited for this study. Resting-state fMRI data were obtained at the subacute phase (mean days 40.63 ± 10.14) and analyzed for functional activation and connectivity, independent component analysis, and effective connectivity within and between the DMN. Neuropsychological tests were also performed to assess the cognitive and memory domains. Compared to the HC, the TBI group exhibited lower activation in the thalamus, as well as significant functional hypoconnectivity between DMN and LN. Within the DMN nodes, decreased activations were detected in the left inferior parietal lobule, precuneus, and right superior frontal gyrus. Altered effective connectivities were also observed in the TBI group and were linked to the diminished activation in the left parietal region and precuneus. With regard to intra-DMN connectivity within the TBI group, positive correlations were found in verbal and visual memory with the language network, while a negative correlation was found in the cognitive domain with the visual network. Our results suggested that aberrant activities and functional connectivities within the DMN and with other RSNs were accompanied by the altered effective connectivities in the TBI group. These alterations were associated with impaired cognitive and memory domains in the TBI group, in particular within the language domain. These findings may provide insight for future TBI observational and interventional research.

The roles of caffeine and corticosteroids in modulating cortical excitability after paired associative stimulation (PAS) and transcranial alternating current stimulation (tACS) in caffeine-naïve and caffeine-adapted subjects

The modulatory effects of non-invasive brain stimulation (NIBS) are highly variable between subjects. This variability may be due to uncontrolled caffeine consumption and circadian rhythms. Therefore, here we studied if caffeine consumption, systemically available caffeine measured in saliva, and daytime have effects on the excitability and plasticity of the motor cortex. Since both, time of the day and caffeine may mediate their effects via cortisol, we also quantified corticosteroids in saliva. Experiment 1 was performed in caffeine-naïve participants (n = 30) and compared the effects of PAS or tACS with different stimulation intensities on the motor cortex with or without caffeine 200 mg administered in a double-blind fashion. Experiment 2 was performed in regular caffeine consumers (n = 30) and compared the influence of time of day on the effects of tACS (true or sham) on the motor cortex also with or without caffeine administered in a double-blind fashion. Caffeine increased the saliva corticosteroid concentrations in both experimental groups, and corticosteroid concentrations were higher in the morning in caffeine consumers. Gender also affected corticosteroid concentrations. There was a positive correlation between caffeine concentrations and baseline cortical excitability in caffeine-adapted participants, and a negative correlation between poststimulation caffeine concentrations and motor evoked potential (MEP) amplitudes after sham stimulation in caffeine-naïve subjects. No correlations were found between poststimulation caffeine or corticosteroid concentrations, and plasticity aftereffects. PAS and tACS did not elicit changes in the corticosteroid concentrations. We conclude that moderate caffeine consumption alters cortical excitability but not plasticity aftereffects. This study was registered in the ClinicalTrials.gov with these registration IDs: 1) NCT03720665 https://clinicaltrials.gov/ct2/results?cond=NCT03720665&term=&cntry=&state=&city=&dist= 2) NCT04011670 https://clinicaltrials.gov/ct2/results?cond=&term=NCT04011670&cntry=&state=&city=&dist=.

The Influence of Demographic, Clinical, Psychological and Functional Determinants on Post-stroke Cognitive Impairment at Day Care Stroke Center, Malaysia

BACKGROUND

This study aims to estimate the prevalence and explore the predictors for post-stroke cognitive impairment at the community level in Malaysia.

METHODS

A total of 50 stroke patients aged 29 to 81-year-old were included in this study. A face to face interview was conducted to gather the demographic and clinical data. Subsequently, assessments including Barthel ADL Index (BI), Addenbrooke's Cognitive Examination-Revised (ACE-R) and Hospital Anxiety and Depression Scale (HADS) were administered to the subjects.

RESULTS

The results showed that the prevalence of cognitive impairment was 76% among the studied populations. The subjects' race (Fisher's value= 9.56, P < 0.05) and education level (Fisher's value = 7.29, P < 0.05) were significantly associated with the cognitive status. The depression score was significantly higher in cognitively impaired group [t (48) = -4.42, P < 0.001] while the Barthel Index score was significantly lower in cognitively impaired group (median = 18.00, P < 0.05). The univariate logistic analysis demonstrated that Chinese (OR 7.33, 95% CI = 1.61-33.51), lower education level (OR 9.33, 95% CI = 0.89-97.62), right sided lesion (OR 0.29, 95% CI = 0.06-1.54), left face weaknesses (OR 0.40, 95% CI 0.09-1.83), high cholesterol (OR 0.45, 95% CI = 0.12-1.75), depression (OR 2.16, 95% CI = 0.85-1.35), and Barthel Index (OR 0.79, 95% CI = 0.57-1.10) were significant predictors. Finally, multivariate logistic regression verified that depression was the only significant predictor of post-stroke cognitive impairment (OR 2.03, 95% CI = 1.20-3.45).

CONCLUSION

In conclusion, the prevalence of cognitive impairment in this study was higher than other community based studies and depression was a risk factor for cognitive impairment.

The association of nuclear abnormalities in exfoliated buccal epithelial cells with the health status of different agricultural activities farmers in Peninsular Malaysia

BACKGROUND

Pesticide exposure possesses risk of genotoxicity to humans, particularly farmers. Despite accumulating evidences linking genotoxicity to pesticide exposure, epidemiological studies to address pesticide toxicity in occupationally exposed farmers in Malaysia remain underreported. Thus, this study was aimed to determine the presence of nuclear abnormalities through the assessment of micronucleus (MN) and binucleus (BNu) frequencies in exfoliated buccal epithelial cells from farmers who were exposed to pesticides. A cross-sectional study of farmers among different agricultural activities farmers in Bachok and Pasir Puteh, Kelantan, North East of Peninsular Malaysia was done to evaluate the presence of nuclear abnormalities and its correlation with their health status and farming activities.

RESULTS

Analysis of buccal cells revealed that the frequency of MN was significantly higher (p < 0.05) in farmers as compared to controls. In contrast, no significant difference (p > 0.05) was observed for BNu frequency in between groups. Correlation analysis showed that apart from a significant (p < 0.05) and positive correlation between the duration of fertilizers exposure and frequencies of MN (r = 0.42, P = 0.001) and BNu (r = 0.37, P = 0.02), no other correlation of various confounding factors on the formation of MN and BNu were observed.

CONCLUSION

In conclusion, pesticide and fertilizers exposure may contribute to the promotion of nuclear anomalies among Malaysian farmers who are engaged in mixed plantation activities. Further assessment of larger populations is important to address and overcome the potential risk of pesticide-induced genotoxicity.

The Ability of Recovery Locus of Control Scale (RLOC) and Post-traumatic Stress Symptoms (PTSS) to Predict the Physical Functioning of Stroke Patients

BACKGROUND

The aim of this study was to address the ability of the recovery locus of control scale (RLOC) and post-traumatic stress symptoms (PTSS) to predict physical functioning among stroke patients. In addition, the best predictors within the subdomains of the RLOC and PTSS were also investigated.

METHODS

A total of 147 stroke patients aged 33-85 years who had intact cognitive functioning were involved in the study. The Recovery Locus of Control Scale (RLOC), the Impact of Event Scale-Revised (IES-R), and the Barthel Index (ADL) were administered to respondents six weeks after stroke.

RESULTS

The results showed that the RLOC and PTSS were significant predictors and were capable of predicting 31% of the physical functioning of stroke patients (adjusted R² = 0.31; P < 0.001). Furthermore, with respect to clinical factors, the affected lesion side contributed to predicting 7% of the physical functioning (R²= 0.07; P < 0.001). A hierarchical regression analysis found that the internal recovery locus of control (IRLOC) was a predictor capable of explaining 18% of the predicted physical functioning (adjusted R²= 0.18; P < 0.001). Meanwhile, avoidance was the most influential significant predictor among PTSS, contributing to 24% of the predicting physical functioning (adjusted R²= 0.24; P < 0.001).

CONCLUSION

In conclusion, the RLOC and PTSS were capable of predicting physical functioning among stroke patients.