Rett syndrome in Ireland: a demographic study

BACKGROUND

Rett syndrome (RTT) is a rare neurodevelopmental condition associated with mutations in the gene coding for the methyl-CpG-binding protein 2 (MECP2). It is primarily observed in girls and affects individuals globally. The understanding of the neurobiology of RTT and patient management has been improved by studies that describe the demographic and clinical presentation of individuals with RTT. However, in Ireland, there is a scarcity of data regarding individuals with RTT, which impedes the ability to fully characterize the Irish RTT population. Together with the Rett Syndrome Association of Ireland (RSAI), we prepared a questionnaire to determine the characteristics of RTT individuals in Ireland. Twenty-five families have participated in the study to date, providing information about demographics, genetics, familial history, clinical features, and regression.

RESULTS

The results show that Irish individuals with RTT have comparable presentation with respect to individuals in other countries; however, they had a better response to anti-epileptic drugs, and fewer skeletal deformities were reported. Nonetheless, seizures, involuntary movements and regression were more frequently observed in Irish individuals. One of the main findings of this study is the limited genetic information available to individuals to support the clinical diagnosis of RTT.

CONCLUSIONS

Despite the limited sample size, this study is the first to characterize the RTT population in Ireland and highlights the importance of having a swift access to genetic testing to sharpen the characterization of the phenotype and increase the visibility of Irish individuals in the international RTT community.

The prevalence and incidence of progressive supranuclear palsy and corticobasal syndrome: a systematic review and meta-analysis

INTRODUCTION

Progressive supranuclear palsy (PSP) and corticobasal syndrome (CBS) are progressive neurodegenerative syndromes characterised by Parkinsonism with additional features including cognitive dysfunction, falls, and oculomotor abnormalities. Understanding the epidemiology of these conditions is critical to planning for future service provision.

METHODS

We conducted a systematic review of studies reporting incidence and prevalence of CBS and PSP. A search of the PubMed and EMBASE data bases was conducted from their date of inception to 13th July 2021. Meta-analysis of studies sharing similar methodologies was carried out to generate estimated pooled prevalence and incidence.

RESULTS

We found 32 studies meeting our criteria for inclusion. There were 20 studies with data on prevalence and 12 with incidence data of PSP. Prevalence of CBS was reported in eight studies while seven studies reported incidence. Reported estimates of prevalence for PSP ranged from 1.00 (0.9-1.1) to 18 (8-28) per 100,000 while prevalence rates for CBS ranged from 0.83 (0.1-3.0) to 25 (0-59). Incidence rates for PSP and CBS respectively ranged from 0.16 (0.07-0.39) to 2.6 per 100,000 person-years and 0.03 (0-0.18) to 0.8 (0.4-1.3) per 100,000 person-years. A random effects model meta-analysis of studies with similar methodologies yielded a pooled prevalence estimate for PSP of 6.92 (4.33-11.06, I2 = 89%, τ2 = 0.3907) and 3.91 (2.03-7.51, I2 = 72%, τ2 = 0.2573) per 100,000 for CBS.

CONCLUSION

Studies of the epidemiology of PSP and CBS report highly heterogeneous findings. There is a need for further studies using rigorous phenotyping and the most recent diagnostic criteria to understand the true burden of these conditions.

Safety and feasibility of transcutaneous vagus nerve stimulation in mild cognitive impairment: VINCI-AD study protocol

BACKGROUND

Over 55 million adults are living with dementia globally, which is projected to reach 157 million by 2050. Mild cognitive impairment (MCI), a syndrome of memory impairment with intact activities of daily living, may precede dementia by several years. Around 5-15% of individuals with MCI convert to dementia annually. Novel treatments which delay progression of MCI to dementia are urgently needed. Transcutaneous vagal nerve stimulation (tVNS) is a non-invasive neuromodulation technique that targets the vagus nerve. Importantly, tVNS has been shown to improve cognition in healthy volunteers, but has not been extensively examined as a potential therapeutic approach in MCI. VINCI-AD will examine the safety and feasibility of tVNS in older adults with MCI.

DESIGN

VINCI-AD is an investigator-led, single-site, single-blind, sham-controlled crossover pilot study which aims to assess the safety and feasibility of tVNS in 40 participants with amnestic MCI. All participants will attend for three consecutive study visits during which they will be randomised to receive no stimulation (baseline), active tVNS stimulation (stimulation at cymba conchae of left ear) or sham tVNS stimulation (at earlobe). Safety will be primarily assessed by ascertainment of adverse events. Further safety assessment will examine the impact of acute tVNS on subjective (orthostatic symptoms), peripheral (finometry-based blood pressure) and central (assessed via Near Infrared Spectroscopy [NIRS]) haemodynamic responses to active stand. Feasibility will be determined using a custom-designed occupational assessment of device usability. Exploratory secondary analysis in VINCI-AD will examine the potential impact of acute tVNS on associative memory, spatial memory and inhibitory control to inform sample size estimates for future trials of tVNS in older adults with MCI.

DISCUSSION

VINCI-AD will report on the safety (adverse events/haemodynamic responses to active stand) and feasibility of tVNS as a potential therapeutic option in MCI. Detailed reporting of study eligibility and completion rates will be reported. Exploratory analysis will examine the potential cognitive benefits of acute tVNS on cognitive function in MCI to report potential effect sizes that may inform future clinical trials in this cohort.

TRIAL REGISTRATION

https://clinicaltrials.gov/ct2/show/NCT05514756 . Trial Registration Number NCT05514756 (24th August 2022 for this protocol, version 1.0.).

An Update on Apathy in Alzheimer's Disease

Apathy is a complex multi-dimensional syndrome that affects up to 70% of individuals with Alzheimer's disease (AD). Whilst many frameworks to define apathy in AD exist, most include loss of motivation or goal-directed behaviour as the central feature. Apathy is associated with significant impact on persons living with AD and their caregivers and is also associated with accelerated cognitive decline across the AD spectrum. Neuroimaging studies have highlighted a key role of fronto-striatial circuitry including the anterior cingulate cortex (ACC), orbito-frontal cortex (OFC) and associated subcortical structures. Importantly, the presence and severity of apathy strongly correlates with AD stage and neuropathological biomarkers of amyloid and tau pathology. Following from neurochemistry studies demonstrating a central role of biogenic amine neurotransmission in apathy syndrome in AD, recent clinical trial data suggest that apathy symptoms may improve following treatment with agents such as methylphenidate-which may have an important role alongside emerging non-pharmacological treatment strategies. Here, we review the diagnostic criteria, rating scales, prevalence, and risk factors for apathy in AD. The underlying neurobiology, neuropsychology and associated neuroimaging findings are reviewed in detail. Finally, we discuss current treatment approaches and strategies aimed at targeting apathy syndrome in AD, highlighting areas for future research and clinical trials in patient cohorts.

Potential costs and consequences associated with medication error at hospital discharge: an expert judgement study

OBJECTIVES

Assessing the cost-effectiveness of complex pharmaceutical care interventions and medication error outcomes is hindered by lack of available data on actual outcomes consequent to errors that were intercepted for patient safety reasons. Expert judgement is an approach to acquire data regarding unknown parameters in an economic model which are otherwise insufficient or not possible to obtain. The aim of this paper is to describe a method to approach this problem using findings from a single intervention study and to calculate the potential costs and consequences associated with discharge medication error.

METHODS

Using data from a previous intervention study, the hypothetical consequences of medication error(s) at hospital discharge, in terms of diagnosis, healthcare resource utilisation and impact on health-related quality of life, were identified by expert judgement of anonymised cases. Primary healthcare utilisation costs were derived from published tariffs, inpatient costs were derived by simulation in the hospital discharge activity database test environment and the difference between adjudicated baseline and posterror health state was expressed as quality-adjusted life year (QALY) decrement.

RESULTS

Four experts provided judgement on 81 cases. Of these, 75 were judged to have potential clinical consequences. Between 56 and 69 of the 81 cases were variably judged to require remedial healthcare utilisation. The mean calculated cost per case (representing an individual patient), based on all 81 cases, was €1009.58, 95% CI 726.64 to 1585.67. The mean QALY loss was 0.03 (95% CI 0.01 to 0.05).

CONCLUSION

An expert judgement process proved feasible and useful to estimate financial cost and QALY loss associated with hospital discharge medication error. These estimates will be employed in model-based economic evaluation. This method could be transferred to other prospective observational patient safety research which seeks to assess value for money of complex interventions.

“The Wandering Nerve Linking Heart and Mind” – The Complementary Role of Transcutaneous Vagus Nerve Stimulation in Modulating Neuro-Cardiovascular and Cognitive Performance

The vagus nerve is the longest nerve in the human body, providing afferent information about visceral sensation, integrity and somatic sensations to the CNS via brainstem nuclei to subcortical and cortical structures. Its efferent arm influences GI motility and secretion, cardiac ionotropy, chonotropy and heart rate variability, blood pressure responses, bronchoconstriction and modulates gag and cough responses via palatine and pharyngeal innervation. Vagus nerve stimulation has been utilized as a successful treatment for intractable epilepsy and treatment-resistant depression, and new non-invasive transcutaneous (t-VNS) devices offer equivalent therapeutic potential as invasive devices without the surgical risks. t-VNS offers exciting potential as a therapeutic intervention in cognitive decline and aging populations, classically affected by reduced cerebral perfusion by modulating both limbic and frontal cortical structures, regulating cerebral perfusion and improving parasympathetic modulation of the cardiovascular system. In this narrative review we summarize the research to date investigating the cognitive effects of VNS therapy, and its effects on neurocardiovascular stability.

Multi-Omic Biomarkers as Potential Tools for the Characterisation of Pancreatic Cystic Lesions and Cancer: Innovative Patient Data Integration

Pancreatic cancer (PC) is regarded as one of the most lethal malignant diseases in the world, with GLOBOCAN 2020 estimates indicating that PC was responsible for almost half a million deaths worldwide in 2020. Pancreatic cystic lesions (PCLs) are fluid-filled structures found within or on the surface of the pancreas, which can either be pre-malignant or have no malignant potential. While some PCLs are found in symptomatic patients, nowadays many PCLs are found incidentally in patients undergoing cross-sectional imaging for other reasons-so called 'incidentalomas'. Current methods of characterising PCLs are imperfect and vary hugely between institutions and countries. As such, there is a profound need for improved diagnostic algorithms. This could facilitate more accurate risk stratification of those PCLs that have malignant potential and reduce unnecessary surveillance. As PC continues to have such a poor prognosis, earlier recognition and risk stratification of PCLs may lead to better treatment protocols. This review will focus on the importance of biomarkers in the context of PCLs and PCand outline how current 'omics'-related work could contribute to the identification of a novel integrated biomarker profile for the risk stratification of patients with PCLs and PC.

The contribution of serum cortisone and glucocorticoid metabolites to detrimental bone health in patients receiving hydrocortisone therapy

BACKGROUND

Glucocorticoid therapy is the most common cause of iatrogenic osteoporosis. Less is known regarding the effect of glucocorticoids when used as replacement therapy on bone remodelling in patients with adrenal insufficiency. Enhanced intracellular conversion of inactive cortisone to active cortisol, by 11 beta-hydroxysteroid dehydrogenase type 1(11β-HSD1) and other enzymes leading to alterations in glucocorticoid metabolism, may contribute to a deleterious effect on bone health in this patient group.

METHODS

Study design: An open crossover prospective study randomizing ten hypopituitary men, with severe ACTH deficiency, to three commonly used hydrocortisone dose regimens.

MEASUREMENTS

Following 6 weeks of each regimen, patients underwent 24-h serum cortisol/cortisone sampling, measurement of bone turnover markers, and a 24-h urine collection for measurement of urinary steroid metabolites by gas chromatography-mass spectrometry (GC-MS). Serum cortisone and cortisol were analysed by liquid chromatography-mass spectrometry (LC-MS).

RESULTS

Dose-related and circadian variations in serum cortisone were seen to parallel those for cortisol, indicating conversion of ingested hydrocortisone to cortisone. The median area under the curve (AUC) of serum cortisone was significantly higher in patients on dose A (20 mg/10 mg) [670.5 (IQR 621-809.2)] compared to those on dose C (10 mg/5 mg) [562.8 (IQR 520.1-619.6), p = 0.01]. A negative correlation was observed between serum cortisone and bone formation markers, OC [1-49] (r = - 0.42, p = 0.03), and PINP (r = - 0.49, p = 0.01). There was a negative correlation between the AUC of night-time serum cortisone levels with the bone formation marker, OC [1-49] (r = - 0.41, p = 0.03) but there were no significant correlations between day-time serum cortisone or cortisol with bone turnover markers. There was a negative correlation between total urinary cortisol metabolites and the bone formation markers, PINP (r = - 0.39, p = 0.04), and OC [1-49] (r = - 0.35, p = 0.06).

CONCLUSION

Serum cortisol and cortisone and total urinary corticosteroid metabolites are negatively associated with bone turnover markers in patients receiving replacement doses of hydrocortisone, with nocturnal glucocorticoid exposure having a potentially greater influence on bone turnover.

TRIAL REGISTRATION

Irish Medicines Board Clinical Trial Number - CT900/459/1 and EudraCT Number - 2007-005018-37 . Registration date: 07-09-2007.

Urinary soluble CD163 and monocyte chemoattractant protein-1 in the identification of subtle renal flare in anti-neutrophil cytoplasmic antibody-associated vasculitis

BACKGROUND

Prior work has shown that urinary soluble CD163 (usCD163) displays excellent biomarker characteristics for detection of active renal vasculitis using samples that included new diagnoses with highly active renal disease. This study focused on the use of usCD163 in the detection of the more clinically relevant state of mild renal flare and compared results of usCD163 testing directly to testing of urinary monocyte chemoattractant protein-1 (uMCP-1).

METHODS

Patients with anti-neutrophil cytoplasmic antibody (ANCA)-associated vasculitis (AAV, n = 88) were identified within a serially sampled, longitudinal and multicentre cohort. Creatinine-normalized usCD163 and uMCP-1 levels were measured by enzyme-linked immunosorbent assay and, both alone and in combination, were compared between times of active renal AAV and during remission and/or active non-renal AAV.

RESULTS

Samples from 320 study visits included times of active renal vasculitis (n = 39), remission (n = 233) and active extrarenal vasculitis (n = 48). Median creatinine levels were 0.9 mg/dL [interquartile range (IQR) 0.8-1.2] in remission and 1.4 mg/dL (IQR 1.0-1.8) during renal flare. usCD163 levels were higher in patients with active renal vasculitis compared with patients in remission and those with active extrarenal vasculitis, with median values of 162 ng/mmol (IQR 79-337), 44 (17-104) and 38 (7-76), respectively (P < 0.001). uMCP-1 levels were also higher in patients with active renal vasculitis compared with patients in remission and those with active extrarenal vasculitis, with median values of 10.6 pg/mmol (IQR 4.6-23.5), 4.1 (2.5-8.4) and 4.1 (1.9-6.8), respectively (P < 0.001). The proposed diagnostic cut-points for usCD163 and uMCP-1 were 72.9 ng/mmol and 10.0 pg/mmol, respectively. usCD163 and uMCP-1 levels were marginally correlated (r2 = 0.11, P < 0.001). Combining novel and existing biomarkers using recursive tree partitioning indicated that elevated usCD163 plus either elevated uMCP-1 or new/worse proteinuria improved the positive likelihood ratio (PLR) of active renal vasculitis to 19.2.

CONCLUSION

A combination of usCD163 and uMCP-1 measurements appears to be useful in identifying the diagnosis of subtle renal vasculitis flare.

Adrenal crisis: prevention and management in adult patients

Adrenal crisis is an acute life-threatening emergency contributing to the excess mortality that is reported in patients with adrenal insufficiency. The incidence of adrenal crisis is estimated to be 8 per 100 patient years in patients with adrenal insufficiency. Patients with adrenal crisis present systemically unwell with nonspecific signs and symptoms often leading to misdiagnosis and delayed treatment. An adrenal crisis may be the first presentation of adrenal insufficiency or can occur in patients who have been established on glucocorticoid replacement therapy. Infections are the major precipitating factor, but other causes include physical stress such as a surgical procedure or trauma, forgetting or discontinuing glucocorticoid therapy, pronounced physical activity, and psychological stress. The emergency treatment involves prompt recognition and administration of parenteral hydrocortisone, rehydration and management of electrolyte abnormalities. Prevention is centred around patient education. All patients should be educated on stress dosing and parenteral glucocorticoid administration. They should carry a steroid dependency alert card and wear a medical alert bracelet or similar identification. Despite many improvements in the management of patients with adrenal insufficiency, adrenal crisis continues to occur and represents a major source of morbidity, mortality and distress for patients. Improved patient and clinician education and measures to facilitate parenteral hydrocortisone self-administration in impending crisis are central to the management of this life-threatening event.

Transcriptome level analysis in Rett syndrome using human samples from different tissues

The mechanisms of neuro-genetic disorders have been mostly investigated in the brain, however, for some pathologies, transcriptomic analysis in multiple tissues represent an opportunity and a challenge to understand the consequences of the genetic mutation. This is the case for Rett Syndrome (RTT): a neurodevelopmental disorder predominantly affecting females that is characterised by a loss of purposeful movements and language accompanied by gait abnormalities and hand stereotypies. Although the genetic aetiology is largely associated to Methyl CpG binding protein 2 (MECP2) mutations, linking the pathophysiology of RTT and its clinical symptoms to direct molecular mechanisms has been difficult.One approach used to study the consequences of MECP2 dysfunction in patients, is to perform transcriptomic analysis in tissues derived from RTT patients or Induced Pluripotent Stem cells. The growing affordability and efficiency of this approach has led to a far greater understanding of the complexities of RTT syndrome but is also raised questions about previously held convictions such as the regulatory role of MECP2, the effects of different molecular mechanisms in different tissues and role of X Chromosome Inactivation in RTT.In this review we consider the results of a number of different transcriptomic analyses in different patients-derived preparations to unveil specific trends in differential gene expression across the studies. Although the analyses present limitations- such as the limited sample size- overlaps exist across these studies, and they report dysregulations in three main categories: dendritic connectivity and synapse maturation, mitochondrial dysfunction, and glial cell activity.These observations have a direct application to the disorder and give insights on the altered mechanisms in RTT, with implications on potential diagnostic criteria and treatments.