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Although comorbidity increases the health care and community support needs for patients, and the burden for the health care system, there are few population-based studies on comorbidity in patients with stroke. This study aims to evaluate the occurrence of important comorbidities among stroke patients in the Canadian population.
Methods:
Data from the population-based 2011–2012 Canadian Community Health Survey containing responses from 124,929 participants covering about 98% of the Canadian population when weighted were examined and analyzed by means of logistic regression models.
Results:
There was a statistically significant association between stroke history and multiple comorbid risk factors. Stroke prevalence increased in individuals with heart disease (odds ratio (OR): 3.80, 95% confidence interval (CI): 3.77–3.84), hypertension (OR: 1.97, 95% CI: 1.95–1.99), diabetes (OR: 1.74, 95% CI: 1.72–1.75), mood disorder (OR: 2.14, 95% CI: 2.12–2.17), and chronic obstructive pulmonary disease (COPD) (OR: 1.46, 95% CI: 1.44–1.48) compared to others without the condition. Of 2067 participants with stroke, 1680 (81.3%) had one or more comorbid conditions (heart disease, hypertension, diabetes, mood disorder, or COPD) that coexist with stroke and 48% had two or more. Comorbidity increased with age, and two-thirds of stroke patients with comorbid medical conditions were 60 years of age or older.
Conclusion:
This population-based study provides evidence of comorbidity between stroke and other conditions that include heart disease, hypertension, diabetes, mood disorder, and COPD. Canadian individuals with stroke have a high burden of comorbidity. Health care systems need to recognize and respond to the strong association of comorbidity and stroke occurrence. This key factor should be considered when allocating resources.
Endovascular thrombectomy (EVT) is effective in reducing disability in selected patients with stroke and large vessel occlusion (LVO), but access to this treatment is suboptimal.
Aim:
We examined the proportion of patients with LVO who did not receive EVT, the reasons for non-treatment, and the association between time from onset and probability of treatment.
Methods:
We conducted a retrospective cohort study of consecutive patients with acute stroke and LVO presenting between January 2017 and June 2018. We used multivariable log-binomial models to determine the association between time and probability of treatment with and without adjustment for age, sex, dementia, active cancer, baseline disability, stroke severity, and evidence of ischemia on computerized tomography.
Results:
We identified 256 patients (51% female, median age 74 [interquartile range, IQR 63.5, 82.5]), of whom 59% did not receive EVT. The main reasons for not treating with EVT were related to occlusion characteristics or infarct size. The median time from onset to EVT center arrival was longer among non-treated patients (218 minutes [142, 302]) than those who were treated (180 minutes [104, 265], p = 0.03). Among patients presenting within 6 hours of onset, the relative risk (RR) of receiving EVT decreased by 3% with every 10-minute delay in arrival to EVT center (adjusted RR 0.97 CI95 [0.95, 0.99]). This association was not found in the overall cohort.
Conclusions:
The proportion of patients with acute stroke and confirmed LVO who do not undergo EVT is substantial. Minimizing delays in arrival to EVT center may optimize the delivery of this treatment.
Damage to the corticospinal tract (CST) from stroke leads to motor deficits. The damage can be quantified as the amount of overlap between the stroke lesion and CST (CST Injury). Previous literature has shown that the degree of motor deficits post-stroke is related to the amount of CST Injury. These studies delineate the stroke lesion from structural T1-weighted magnetic resonance imaging (MRI) scans, often acquired for research. In Canada, computed tomography (CT) is the most common imaging modality used in routine acute stroke care. In this proof-of-principle study, we determine whether CST Injury, using lesions delineated from CT scans, significantly explains the variability in motor impairment in individuals with stroke.
Methods:
Thirty-seven participants with stroke were included in this study. These individuals had a CT scan within the acute stage (7 days) of their stroke and underwent motor assessments. Brain images from CT scans were registered to MRI space. We performed a stepwise regression analysis to determine the contribution of CST injury and demographic variables in explaining motor impairment variability.
Results:
Using clinically available CT scans, we found modest evidence that CST Injury explains variability in motor impairment (R2adj = 0.12, p = 0.02). None of the participant demographic variables entered the model.
Conclusion:
We show for the first time a relationship between CST Injury and motor impairment using CT scans. Further work is required to evaluate the utility of data derived from clinical CT scans as a biomarker of stroke motor recovery.
The purpose of this study was to examine the effectiveness, satisfaction, and acceptance of a low-cost Lombard-response (LR) device in a group of individuals with Parkinson’s disease (IWPD) and their communication partners (CPs).
Method:
Sixteen IWPD and hypophonia and their CPs participated in the study. The IWPD wore a LR device that included a small MP3 player (Sony Walkman) and headphones playing a multi-talker noise audio file at 80 dB during lab-based speech tasks and during their daily conversational speech over a 2-week device trial period. Outcome measures included average conversational speech intensity and scores on a questionnaire related to speech impairment, communication effectiveness, and device satisfaction.
Results:
Conversational speech intensity of the IWPD is increased by 7 to 10 dB with the LR device. Following a 2-week trial period, eight of the IWPD (50%) gave the LR device moderate-to-high satisfaction and effectiveness ratings and decided to purchase the device for long-term daily use. At the 4-month follow-up, none of the IWPDs were still using the LR device. Device rejection was related to discomfort (loudness), headaches, interference with cognition, and difficulty controlling device.
Conclusion:
Short-term acceptance and satisfaction with the LR device was moderate, but long-term acceptance, beyond 4 months, was absent. Future studies are required to determine if other types of low-cost LR devices can be developed that improve long-term efficacy and device acceptance in IWPD and hypophonia.
The diagnosis of anti-N-methyl-d-aspartate receptor (NMDAR) encephalitis relies on the detection of NMDAR IgG autoantibodies in the serum or cerebrospinal fluid (CSF) of symptomatic patients. Commercial kits are available that allow NMDAR IgG autoantibodies to be measured in local laboratories. However, the performance of these tests outside of reference laboratories is unknown.
Objectives:
To report an unexpectedly low rate of NMDAR autoantibody detection in serum from patients with anti-NMDAR encephalitis tested using a commercially available diagnostic kit in an exemplar clinical laboratory.
Methods:
Paired CSF and serum samples from seven patients with definite anti-NMDAR encephalitis were tested for NMDAR IgG autoantibodies using commercially available cell-based assays run according to manufacturer’s recommendations. Rates of autoantibody detection in serum tested at our center were compared with those derived from systematic review and meta-analyses incorporating studies published during or before March 2019.
Results:
NMDAR IgG autoantibodies were detected in the CSF of all patients tested at our clinical laboratory but not in paired serum samples. Rates of the detection were lower than those previously reported. A similar association was recognized through meta-analyses, with lower odds of NMDAR IgG autoantibody detection associated with serum testing performed in nonreference laboratories.
Conclusions:
Commercial kits may yield lower-than-expected rates of NMDAR IgG autoantibody detection in serum when run in exemplar clinical (nonreference) laboratories. Additional studies are needed to decipher the factors that contribute to lower-than-expected rates of serum positivity. CSF testing is recommended in patients with suspected anti-NMDAR encephalitis.
Young-onset dementia (YOD) is defined as the onset of dementia symptoms before the age of 65 years and accounts for 2–8% of dementia. YOD patients and their caregivers face unique challenges in diagnosis and management. We aimed to compare the characteristics of rural YOD and late-onset dementia (LOD) patients at a rural and remote memory clinic in Western Canada.
Methods:
A total of 333 consecutive patients (YOD = 61, LOD = 272) at a rural and remote memory clinic between March 2004 and July 2016 were included in this study. Each patient had neuropsychological assessment. Health, mood, function, behaviour and social factors were also measured. Both groups were compared using χ2 tests and independent sample tests.
Results:
YOD patients were more likely to be married, employed, current smokers and highly educated. They reported fewer cognitive symptoms, but had more depressive symptoms. YOD patients were less likely to live alone and use homecare services. YOD caregivers were also more likely to be a spouse and had higher levels of distress than LOD caregivers. Both YOD and LOD patient groups were equally likely to have a driver’s licence.
Conclusions:
Our findings indicate YOD and LOD patients have distinct characteristics and services must be modified to better meet YOD patient needs. In particular, the use of homecare services and caregiver support may alleviate the higher levels of distress found in YOD patients and their caregivers. Additional research should be directed to addressing YOD patient depression, caregiver distress and barriers to services.
Involving stakeholders has been acknowledged as a way to improve quality and relevance in health research. The mechanisms that support effective research engagement with stakeholders have not been studied in the area of concussion. Concussion is a large public health concern worldwide with billions of dollars spent on health care services and research with improvements in care and service delivery not moving forward as quickly as desired. Enabling effective stakeholder engagement could improve concussion research and care.
Objective:
The aim of the study was to identify potential benefits, challenges, and motivators to engaging in research by gathering the perspectives of adults with lived experience of concussion.
Methods:
A thematic analysis of qualitative responses collected from a convenience sample attending a provincial brain injury conference (n = 60) was undertaken using open coding followed by axial coding.
Results:
Four themes regarding benefits to engagement emerged: first-hand account, meaningful recovery, research relevance, and better understanding of gaps. Three forces inhibited engagement: environmental barriers, injury-related constraints, and personal deterrents. Four enablers supported engagement: focus on positive impact, build connections, create a supportive environment, and provide financial assistance.
Conclusions:
Understanding stakeholder’s perspectives on research engagement is an important issue that may serve to improve research quality. There may be unique nuances at play with injury-specific stakeholders that require researchers to consider a balance between reducing inhibitors while supporting enablers. These findings are preliminary and limited. Nevertheless, they provide needed insight and guidance for ongoing investigation regarding improvement of stakeholder engagement in concussion research.
Female stroke patients may experience poorer functional outcomes than males following inpatient rehabilitation.
Methods:
Data from Alberta inpatient stroke rehabilitation units were examined to determine: (1) the impact of sex on time to inpatient rehabilitation, functional gains (using the Functional Independence Measure (FIM)), length of stay (LOS), and discharge destination; (2) if sex was related to age at the time of stroke, stroke severity, and living arrangement at discharge from rehabilitation; and (3) whether patients’ age and preadmission living arrangement had an influence on LOS in rehabilitation or discharge destination.
Results:
Two thousand two hundred sixty-six adult stroke patients (1283 males and 983 females) were subcategorized as mild (FIM >80; n = 1155), moderate (FIM 40–80; n = 994), or severe (FIM <40; n = 117). Fifty-five percent of males (45.7% females) had mild stroke; 39.5% of males (49.5% females) had moderate stroke; and 5.5% of males (4.8% females) had severe stroke. Females were significantly older than males (p = 2.4 × 10−4). No sex difference existed in time from acute care to rehabilitation admission (p = 0.73) or in mean FIM change (p = 0.294). Mean LOS was longer for females than males (p=0.018). Males were more likely than females to be discharged home (p = 1.8 × 10−13). Further, male patients (p = 6.4 × 10−7) and those < 65 years (p = 1.4 × 10−23) were more likely to be discharged home without homecare.
Conclusion:
There are significant sex and age differences in LOS in rehabilitation and discharge destination of stroke patients. These differences may suggest that sex and age of the patient need to be considered in care planning.
Isolated, subtle neurological abnormalities (ISNA) are commonly seen in aging and have been related to cerebral small vessel disease (SVD) and subcortical atrophy in neurologically and cognitively healthy aging subjects.
Objective:
To investigate the frequency of ISNA in different mild cognitive impairment (MCI) types and to evaluate for each MCI type, the cross-sectional relation between ISNA and white matter hyperintensities (WMH), lacunes, caudate atrophy, and ventricular enlargement.
Methods:
One thousand two hundred fifty subjects with different MCI types were included in the analysis and underwent brain magnetic resonance imaging. WMHs were assessed through two visual rating scales. Lacunes were also rated. Atrophy of the caudate nuclei and ventricular enlargement were assessed through the bicaudate ratio (BCr) and the lateral ventricles to brain ratio (LVBr), respectively. Apolipoprotein E (APOE) genotypes were also assessed. The routine neurological examination was used to evaluate ISNAs that were clustered as central-based signs, cerebellar-based signs, and primitive reflexes. The items of Part-III of the Unified Parkinson’s Disease Rating Scale were used to evaluate ISNAs that were clustered as mild parkinsonian signs. Associations of ISNAs with imaging findings were determined through logistic regression analysis.
Results:
The ISNAs increase with the age and are present in all MCI types, particularly in those multiple domains, and carrying the APOE ϵ4 allele, and are associated with WMH, lacunes, BCr, and LVBr.
Conclusion:
This study demonstrates that cortical and subcortical vascular and atrophic processes contribute to ISNAs. Long prospective population-based studies are needed to disentangle the role of ISNAs in the conversion from MCI to dementia.
To examine whether sociodemographic characteristics and health care utilization are associated with receiving deep brain stimulation (DBS) surgery for Parkinson’s disease (PD) in Ontario, Canada.
Methods:
Using health administrative data, we identified a cohort of individuals aged 40 years or older diagnosed with incident PD between 1995 and 2009. A case-control study was used to examine whether select factors were associated with DBS for PD. Patients were classified as cases if they underwent DBS surgery at any point 1-year after cohort entry until December 31, 2016. Conditional logistic regression modeling was used to estimate the adjusted odds of DBS surgery for sociodemographic and health care utilization indicators.
Results:
A total of 46,237 individuals with PD were identified, with 543 (1.2%) receiving DBS surgery. Individuals residing in northern Ontario were more likely than southern patients to receive DBS surgery [adjusted odds ratio (AOR) = 2.23, 95% confidence interval (CI) = 1.15–4.34]; however, regional variations were not observed after accounting for medication use among older adults (AOR = 1.04, 95% CI = 0.26–4.21). Patients living in neighborhoods with the highest concentration of visible minorities were less likely to receive DBS surgery compared to patients living in predominantly white neighborhoods (AOR = 0.27, 95% CI = 0.16–0.46). Regular neurologist care and use of multiple PD medications were positively associated with DBS surgery.
Conclusions:
Variations in use of DBS may reflect differences in access to care, specialist referral pathways, health-seeking behavior, or need for DBS. Future studies are needed to understand drivers of potential disparities in DBS use.
The T2 hypointensity has been suggested to be associated with intracranial metastatic adenocarcinomas (IMA). The purpose of our study was to determine the association of T2 hypointensity with IMA.
Methods:
All patients with pathologically confirmed metastatic brain tumors who had a magnetic resonance imaging (MRI) at our institution in the last 10 years were retrospectively assessed. Qualitative assessment of the lesions on MRI was done by two separate readers who were blinded to the pathological diagnosis. For qualitative assessment, the T2 hypointensity in the lesion was compared with the contralateral normal appearing white matter. Odds ratio, sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) were calculated.
Results:
Of 107 patients with intracranial metastasis, only 73 (40 females; 33 males; mean age 61 years) had MRI available for review. Of these, only 46 (25 females; 21 males; mean age 61 years) had pathologically proven IMA. T2 hypointensity was seen in 20% of IMA. The odds ratio of T2 hypointensity in IMA was 3 compared to nonadenocarcinomas but was not statistically significant (p = 0.16). Intralesional hemorrhage was seen in 20. When controlled for hemorrhage, the odds ratio for T2 hypointensity in IMA was 4.7. The specificity, sensitivity, PPV, and NPV for T2 hypointensity to diagnose IMA were 92%, 19%, 81%, and 40%, respectively.
Conclusion:
T2 hypointensity was seen only in 20% of IMA with an odds ratio of 4.7. T2 hypointensity showed a high specificity and PPV for diagnosis of IMA.
Novel neurointerventions present innovative therapeutic approaches to a range of treatment-refractory disorders. We sought to characterize factors that inform and define translational readiness for first-in-human (FIH) neuromodulatory trials.
Methods:
We used a two-part methodology involving a scoping review of the biomedical literature on the readiness of FIH trials for both neurological and non-neurological applications, and semi-structured interviews with stakeholders about decision-making for neuromodulation using magnetic resonance-guided focused ultrasound as a case example.
Results:
One hundred and thirty factors relevant to FIH readiness were identified in the scoping review. Trial design, adequacy of preclinical evidence, and risk were ubiquitous across biotechnologies. Target organ, target function, and inadequacy of animal models were dominant in the neurointervention literature. Interview results on the relative importance of these factors reveal divergent values, priorities, and understandings both between patients and clinicians and between patients affected by different conditions.
Conclusion:
Readiness of neurotechnology for FIH trials is defined by a multitude of interacting factors that pertain to clinical and nonclinical priorities, perceptions, and values.
To evaluate the short-term and long-term clinical effectiveness and safety of subthalamic nucleus deep brain stimulation (STN-DBS) for medically intractable pediatric isolated dystonia.
Methods:
Using a longitudinal retrospective design, we assessed the clinical outcomes of nine patients who underwent STN-DBS for treatment-refractory pediatric isolated dystonia one decade ago (mean age at surgery: 15.9 ± 4.5 years). The primary clinical outcome used was assessed by retrospective video analyses of patients’ dystonia symptoms using the Burke–Fahn–Marsden Dystonia Rating Scale (BFMDRS). Clinical assessments were performed at baseline, 1-year follow-up (1-yr FU), and 10-year follow-up (10-yr FU). Adverse side effects, including surgery-related, device-related, and stimulation-related effects, were also documented.
Results:
After STN-DBS surgery, the mean improvement in the BFMDRS motor score was 77.1 ± 26.6% at 1-yr FU and 90.4 ± 10.4% at 10-yr FU. Similarly, the mean BFMDRS disability score was improved by 69.5 ± 13.6% at 1-yr FU and by 86.5 ± 13.9% at 10-yr FU. The clinical improvements gained at 10-yr FU were significantly larger than those observed at 1-yr FU. Negative correlations were found between the duration of disease to age at surgery ratio (DD/AS) and the improvements in the BFMDRS motor score and total score at 1-yr FU and 10-yr FU.
Conclusion:
To our knowledge, this study provides the first clinical evidence for the short- and long-term effectiveness and safety of STN-DBS for pediatric isolated dystonia. Additionally, putative evidence is provided that earlier STN-DBS intervention in patients with refractory pediatric isolated dystonia may improve short- and long-term clinical outcomes.
Interhemispheric subdural hematomas (IHSDHs) are thought to be rare. Surgical management of these lesions presents a challenge as they are in close proximity to the sagittal sinus and bridging veins. IHSDHs are poorly characterized clinically and their exact incidence is unknown. There are also no clear guidelines for the management of IHSDH.
Methods:
This is a retrospective review of all admitted patients with a diagnosis of traumatic brain injury over a 4-year period at a Level I trauma centre. Clinical characteristics of all patients with subdural hematoma (SDH) and IHSDH were collected.
Results:
Of 2165 admissions, 1182 patients had acute traumatic SDHs, 420 patients had IHSDHs (1.9% of admissions and 35.5% of SDH), 35 (8.3% of IHSDH) were ≥8 mm in width. IHSDH was isolated in 16 (3.8%) of the cases. Average age was 61.7 ± 21.5 years for all IHSDHs and 77.1 ± 10.4 for large IHSDH (p < 0.001). For large IHSDH, a transient loss of consciousness (LOC) occurred in 51.5% of individuals, post-traumatic amnesia (PTA) in 47.8% of cases, and motor weakness in 37.9% of patients. Five of the large IHSDH patients presented with motor deficits directly related to the IHSDH, and weakness resolved in four of these five individuals. None were treated surgically. Progression of IHSDH width occurred in one patient.
Conclusion:
IHSDHs are often referred to as rare entities. Our results show they are common. Conservative management is appropriate to manage most IHSDHs, as most resolve spontaneously, and their symptoms resolve as well.
Hyperbaric oxygen therapy (HBOT) shows promising results in treating radionecrosis (RN) but there is limited evidence for its use in brain RN. The purpose of this study is to report the outcomes of using HBOT for symptomatic brain RN at a single institution.
Methods:
This was a retrospective review of patients with symptomatic brain RN between 2008 and 2018 and was treated with HBOT. Demographic data, steroid use, clinical response, radiologic response and toxicities were collected. The index time for analysis was the first day of HBOT. The primary endpoint was clinical improvement of a presenting symptom, including steroid dose reduction.
Results:
Thirteen patients who received HBOT for symptomatic RN were included. The median time from last brain radiation therapy to presenting symptoms of brain RN was 6 months. Twelve patients (92%) had clinical improvement with median time to symptom improvement of 33 days (range 1–109 days). One patient had transient improvement after HBOT but had recurrent symptomatic RN at 12 months. Of the eight patients with evaluable follow-up MRI, four patients had radiological improvement while four had stable necrosis appearance. Two patients had subsequent deterioration in MRI appearances, one each in the background of initial radiologic improvement and stability. Median survival was 15 months with median follow-up of 10 months. Seven patients reported side effects attributable to HBOT (54%), four of which were otologic in origin.
Conclusions:
HBOT is a safe and effective treatment for brain RN. HBOT showed clinical and radiologic improvement or stability in most patients. Prospective studies to further evaluate the effectiveness and side effects of HBOT are needed.
Pain is a non-motor symptom in Parkinson’s disease (PD) which commonly goes underreported. Adequate treatment for pain in PD remains challenging, and to date, no clear guidelines for management are available.
Methods:
With the goal of understanding and organizing the current status of pain management in PD, we conducted a review of pharmacological and non-pharmacological treatments for pain in patients with PD. Suitable studies cataloged in PubMed and the Cochrane database up to October 31, 2019, were included prioritizing randomized controlled trials. Post-hoc analyses and open-label studies were also included.
Results:
Treatment with levodopa increases pain thresholds in patients with PD. Apomorphine did not have similar efficacy. Duloxetine provided benefit in an open-label trial. Oxycodone-naloxone PR did not have a significant improvement in pain, but per-protocol analysis showed a reduction in pain when adherence was strong. Rotigotine patch had numerical improvement on pain scales with no statistical significance. Safinamide significantly improved the “bodily discomfort” domain in the PDQ-39 questionnaire. Botulinum toxin A had a non-significant signal toward improving dystonic limb pain in PD. DBS to the subthalamic nucleus may modulate central pain thresholds, and a pilot study of cranioelectric therapy warrants future research in the area.
Conclusion:
After optimizing dopaminergic therapy, understanding the type of pain a patient is experiencing is essential to optimizing pain control in PD. While recommendations can be made regarding the treatment options in each domain, evidence remains weak and future randomized controlled studies are needed.
Medical cannabis has recently emerged as a treatment option for children with drug-resistant epilepsy. Despite the fact that many pediatric epilepsy patients across Canada are currently being treated with cannabis, little is known about the attitudes of neurologists toward cannabinoid treatment of children with epilepsy.
Methods:
A 21-item online survey was distributed via email to 148 pediatric neurologists working in hospitals and community clinics across Canada. Questions were related to clinical practice and demographics.
Results:
This survey achieved a response rate of 38% (56 Canadian neurologists). These neurologists were treating 668 pediatric epilepsy patients with cannabinoids. While 29% of neurologists did not support cannabis treatment in their patients, 34% prescribed cannabis, and 38% referred to another authorizing physician, mostly to community-based non-neurologists. The majority of neurologists considered cannabis for patients with Dravet syndrome (68%) and Lennox–Gastaut syndrome (64%) after an average of three failed anticonvulsants. Twenty-seven percent considered it for patients with idiopathic generalized epilepsy, and 18% for focal epilepsy. No neurologist used cannabis as a first-line treatment. All neurologists had at least one hesitation regarding cannabis treatment in pediatric epilepsy. The most common one was poor evidence (66%), followed by poor quality control (52%) and high cost (50%).
Conclusions:
The majority of Canadian pediatric neurologists consider using cannabis as a treatment for epilepsy in children. With many gaps in evidence and high patient-driven demand for cannabis therapy, this survey provides immediate information from the “wisdom of the crowd,” to aid neurologists until further evidence is available.
Serotonin (5-HT) is a neurotransmitter synthesized in both the central nervous system (CNS) and in enterochromaffin cells of the gut. 5-HT biosynthesis is separate between the periphery and the CNS. Any observed correlations between centrally and peripherally measured 5-HT remain to be elucidated. Previous efforts have looked for a noninvasive marker of central serotonin, including serotonin in whole blood, plasma, platelets, saliva, and urine; however, results are conflicting.
Aim:
Finding a noninvasive marker for central serotonin turnover that can be used for diagnosis and therapeutic monitoring in patients with primary neurotransmitter deficiencies.
Methods:
Inclusion criterion was all children presenting with neurological symptoms whose clinical investigations included lumbar puncture (LP) for cerebrospinal fluid (CSF) collection and neurotransmitter metabolite analysis, were recruited. For central serotonin turnover, the serotonin metabolite 5-hydroxyindoleacetic acid (5HIAA) was used. Bivariate correlation between the serotonin levels in CSF (5HIAA), platelets, and saliva was calculated.
Results:
Twenty-six patients (aged 6 months to 15 years) with various neurologic presentations had LP for CSF collection and neurotransmitter metabolite analysis as part of their clinical care. An additional salivary and blood sample was obtained at the same time. Eighteen patients had suitable samples for quantitative measure of serotonin. There was no correlation between platelet serotonin and CSF 5HIAA levels (Pearson’s coefficient of correlation – PCC: 0.010) or between salivary serotonin and CSF 5HIAA (PCC: 0.258). There was a strong negative correlation between salivary and platelet serotonin (PCC: −0.679).
Conclusion:
Our findings suggest that salivary serotonin measurement is not a suitable noninvasive marker for measuring central serotonin turnover.
Contrast-enhanced magnetic resonance imaging (CEMRI) of the head is frequently employed in investigations of sensorineural hearing loss (SNHL). The yield of these studies is perceptibly low and seemingly at odds with the aims of wise resource allocation and risk reduction within the Canadian healthcare system. The purpose of our study was to audit the use and diagnostic yield of CEMRI for the clinical indication of SNHL in our institution and to identify characteristics that may be leveraged to improve yield and optimize resource utilization.
Materials and methods:
The charts of 500 consecutive patients who underwent CEMRI of internal auditory canal for SNHL were categorized as cases with relevant positive findings on CEMRI and those without relevant findings. Demographics, presenting symptoms, interventions and responses, ordering physicians, and investigations performed prior to CEMRI testing were recorded. Chi-squared test and t-test were used to compare proportions and means, respectively.
Results:
CEMRI studies revealed relevant findings in 20 (6.2%) of 324 subjects meeting the inclusion criteria. Pre-CEMRI testing beyond audiometry was conducted in 35% of those with relevant positive findings compared to 7.3% of those without (p < 0.001). Auditory brainstem response/vestibular-evoked myogenic potentials were abnormal in 35% of those with relevant CEMRI findings compared to 6.3% of those without (p < 0.001).
Conclusion:
CEMRI is a valuable tool for assessing potential causes of SNHL, but small diagnostic yield at present needs justification for contrast injection for this indication. Our findings suggest preferred referral from otolaryngologists exclusively, and implementation of a non-contrast MRI for SNHL may be a better diagnostic tool.
High-grade gliomas (HGGs) are aggressive tumors that inevitably recur due to their diffusely infiltrative nature. Intraoperative adjuncts such as 5-aminolevulinic acid (5-ALA) have shown promise in increasing extent of resection. As the prospect of increased use of 5-ALA rises, a systematic overview of the health economics of this adjunct is critical.
Methods:
Medline, EMBASE, Centre for Reviews and Dissemination, EconPapers, and Cochrane databases were searched for keywords relating to glioma, cost-effectiveness, and 5-ALA. Primary studies reporting on the health economics or cost-effectiveness of 5-ALA compared to white light surgery in HGG were included. Quality was assessed using the British Medical Journal guidelines.
Results:
Three studies were identified. All were European and conducted from the perspective of national healthcare systems. Two studies demonstrated the cost-utility of 5-ALA compared to white light (C$12,817 and C$13,508/quality-adjusted life-years (QALYs)). One assessed the cost-utility per gross total resection (C$6,813). Both these values were below the national cost-effectiveness thresholds for each respective study. The third study demonstrated no significant difference in cost of 5-ALA in glioblastoma resection (C$14,732) compared to prior to its routine use (C$15,936). The quality of these studies ranged from moderate to average. None of these studies considered patient perspective or indirect costs in their analysis.
Conclusions:
Growing evidence exists examining the health economic benefit of 5-ALA as an intraoperative adjunct for HGG resection. Additional studies within the Canadian context using 5-ALA, specifically incorporating patient and societal perspectives into the cost-utility analyses, are necessary to solidify this line of evidence.