Neurological conditions

Introduction: Transcranial Doppler ultrasonography (TCD) and Near-Infrared spectroscopy (NIRS) are indirect measures of neurovascular coupling (NVC). NVC is the relationship between cerebral blood flow and neuronal activity to meet the metabolic demands of the brain. No studies have integrated TCD-NIRS to investigate the feasibility of measuring NVC in those with dementia, delirium, and depression.

Methods: 34 participants (median [IQR] age 73.0 [70.0,79.25], 52.9% female, healthy (HC, n=10), depression (n=11), dementia (n=8), delirium (n=5)), underwent continuous cerebral blood velocity measurements in the middle (dominant MCAv) and posterior (non-dominant PCAv) cerebral arteries using TCD at rest and in response to four tasks. Heart rate (3-lead ECG), end-tidal CO (nasal capnography), blood pressure (Finometer), and prefrontal oxygenated (HbO2) and deoxygenated (HbR) haemoglobin (NIRS) were also measured. NVC was determined as absolute change in MCAv (cm/s) or concentration change for an attention task (serial subtraction), passive motor (arm movement) and passive sensory task (cotton wool), or PCAv for a visuospatial task (dot counting). We determined differences in NVC by a mixed two-way repeated measures analysis of variance, with post-hoc testing via Tukey.

Results: Resting CBv (cm/s) was significantly different between groups in MCAv (HC: 53.9 (SD=8.09), depression: 41.9 (9.31), dementia: 42.5 (13.7), delirium: 32.6 (7.48), p=0.002) and PCAv (p=0.045), after correction for age and BP (p=0.011). TCD: initial NVC responses increased for all three groups (delirium excluded) for all tasks (20-30s), (p=0.021), but with no main effect of diagnosis. NIRS: There was a significant difference between tasks for the HbO2 and HbR responses (p=0.036, p=0.029). Diagnosis had a significant effect on the HbR response only (p=0.027).

Conclusion: An integrated TCD-NIRS protocol was feasible in these patient groups to measure NVC, but less-so in delirium. Further work is needed to investigate NVC using integrated TCD-NIRS in larger sample sizes.

 Introduction: The COVID-19 pandemic has raised concerns about its long-term effects, leading to conditions such as "Long COVID." Neurological manifestations, including "Brain Fog" with impaired cognitive function, have been reported, but their relationship with age and memory decline remains unclear. Method: This study aimed to investigate the effects of COVID-19 infection on memory function and explore the relationship between age and memory scores. The research utilized data from the 'COVID-19 Online Rapid Objective Neuro-memory Assessment' (CORONA) study, employing an online survey with a memory task. Ethical approval was obtained, and participants aged 18 and older were recruited globally, with 5,308 participants included in the analysis. Memory scores were obtained through a task featuring four categories. Statistical analysis, including T-tests and linear regression, was employed to evaluate the data. Results: Participants testing positive for COVID-19 (n = 678) exhibited lower mean total memory scores than those testing negative (n = 4,630), with a statistically significant difference (P < 0.05). Hospitalized COVID-19 patients (n = 37) had significantly lower memory scores compared to non-hospitalized patients (n = 641), suggesting a greater impact of hospitalization on memory function. Age was associated with declining memory scores, with an overall trend of decreasing scores as age increased. Three age groups exhibited significant differences in memory scores between COVID-19 positive and negative participants. Conclusion This study provides evidence that COVID-19 infection may be associated with worsened memory outcomes and cognitive function. Hospitalization due to COVID-19 appears to have a more substantial impact on memory than the infection alone. A steeper decline in memory scores with age was observed among COVID-19-positive participants, suggesting potential age-related vulnerability to memory decline associated with COVID-19. However, discrepancies in results may be attributed to sample size limitations, emphasizing the need for larger cohorts in future research. 

Introduction: The administration of melatonin and melatonin receptor agonists (MRA) may result in a small improvement in sleep quality among middle-aged and older adults living with neurocognitive disorders, but debate remains as to whether effects are clinically meaningful. The purpose of this PROSPERO-registered systematic review and meta-analysis (CRD42022373972) was to synthesise evidence from randomized controlled trials (RCTs) of melatonin or MRA against placebo and other interventions for the treatment of sleep disturbances in adults with neurocognitive disorders.

Method: CENTRAL, MEDLINE, EMBASE, AMED, CINAHL and PsycINFO were systematically searched on November 4th 2022, examining the effect of melatonin and MRA on sleep efficiency: the percentage of time spent asleep while in bed. Results were analysed using Review Manager 5.4. Risk of bias was assessed using RoB 2 and the certainty of evidence was assessed with the GRADE framework.

Results: Among the 1,579 references evaluated, 13 RCTs were selected, corresponding to 16 studies, none including MRA, with a total of 592 patients. Compared with placebo, bright light treatment, or clonazepam, sleep efficiency significantly improved with melatonin administration (MD = 2.85, 95% CI: 0.88 to 4.81, p = 0.004). In subgroup analyses, only low doses of melatonin (< 5 mg) yielded a statistically significant improvement to sleep efficiency (MD = 3.81, 95% CI: 1.13 to 6.49, p = 0.005, I² = 34%), and melatonin administration statistically significantly improved sleep efficiency in patients with Mild Cognitive Impairment, Parkinson's Disease, or Multiple Sclerosis (MD = 3.27, 95% CI: 0.11 to 6.43, p = 0.04, I² = 41%), but not patients with Alzheimer's Disease. We found the overall quality of evidence to be moderate according to GRADE.

Conclusion: Melatonin may modestly ameliorate sleep quality in patients with neurocognitive disorders by improving sleep efficiency, which may be clinically significant to patients and those who care for them.

Introduction

In Scotland, more than 18,000 older people are admitted to hospital after a fall each year. One in three people over the age of 65 experience a fall at least once each year (1). Neurological examination is an essential part of the initial assessment of these patients in hospital and can determine the cause of falls such as stroke, peripheral neuropathies and Parkinson’s disease. Local anecdotal evidence suggested that this was often not carried out, with the potential for delayed diagnosis and treatment.

Method

Baseline data was collected from clinical notes of admissions to the care of the elderly (COTE) wards at University Hospital Hairmyres (UHH) over a 1-month period. Multiple departmental education sessions were arranged to highlight to medical staff the importance of neurological examination in patients presenting to hospital following a fall. Following these sessions the data collection cycle was repeated. A poster has now been designed highlighting common causes of falls and in particular emphasising the importance of performing a neurological examination, with a further cycle of data collection planned.

Results

36.8% of patients admitted to COTE wards in August 2022 were admitted with falls, with only 23% of patients having a neurological exam documented on admission. Following the initial intervention, 30 patients’ notes were reviewed in January 2023. 56.7% of patients were admitted with falls and frequency of documented neurological examination had increased to 58.8%.

Conclusion

Educational sessions resulted in a 156% increase in documented neurological examinations for patients admitted with falls. We hope this improvement will lead to earlier identification of causes of patients’ falls, allowing prompt management. Our project is ongoing, with planned implementation of posters as a secondary intervention, with further data collection in due course.

References

1. NHS Inform. Why Falls Matter. Available from: https://www.nhsinform.scot/healthy-living/preventing-falls/why-falls-matter (accessed 27 November 2022).