Olfactory assessment using the NIH Toolbox

Using SCENTinel® to predict SARS-CoV-2 infection: insights from a community sample during dominance of Delta and Omicron variants

Introduction

Based on a large body of previous research suggesting that smell loss was a predictor of COVID-19, we investigated the ability of SCENTinel®, a newly validated rapid olfactory test that assesses odor detection, intensity, and identification, to predict SARS-CoV-2 infection in a community sample.

Methods

Between April 5, 2021, and July 5, 2022, 1,979 individuals took one SCENTinel® test, completed at least one physician-ordered SARS-CoV-2 PCR test, and endorsed a list of self-reported symptoms.

Results

Among the of SCENTinel® subtests, the self-rated odor intensity score, especially when dichotomized using a previously established threshold, was the strongest predictor of SARS-CoV-2 infection. SCENTinel® had high specificity and negative predictive value, indicating that those who passed SCENTinel® likely did not have a SARS-CoV-2 infection. Predictability of the SCENTinel® performance was stronger when the SARS-CoV-2 Delta variant was dominant rather than when the SARS-CoV-2 Omicron variant was dominant. Additionally, SCENTinel® predicted SARS-CoV-2 positivity better than using a self-reported symptom checklist alone.

Discussion

These results indicate that SCENTinel® is a rapid assessment tool that can be used for population-level screening to monitor abrupt changes in olfactory function, and to evaluate spread of viral infections like SARS-CoV-2 that often have smell loss as a symptom.

Evaluation of the NIH Toolbox Odor Identification Test across normal cognition, amnestic mild cognitive impairment, and dementia due to Alzheimer's disease

INTRODUCTION

Olfactory decline is associated with cognitive decline in aging, amnestic mild cognitive impairment (aMCI), and amnestic dementia associated with Alzheimer's disease neuropathology (ADd). The National Institutes of Health Toolbox Odor Identification Test (NIHTB-OIT) may distinguish between these clinical categories.

METHODS

We compared NIHTB-OIT scores across normal cognition (NC), aMCI, and ADd participants (N = 389, ≥65 years) and between participants positive versus negative for AD biomarkers and the APOE ε4 allele.

RESULTS

NIHTB-OIT scores decreased with age (p < 0.001) and were lower for aMCI (p < 0.001) and ADd (p < 0.001) compared to NC participants, correcting for age and sex. The NIHTB-OIT detects aMCI (ADd) versus NC participants with 49.4% (56.5%) sensitivity and 88.8% (89.5%) specificity. NIHTB-OIT scores were lower for participants with positive AD biomarkers (p < 0.005), but did not differ based on the APOE ε4 allele (p > 0.05).

DISCUSSION

The NIHTB-OIT distinguishes clinically aMCI and ADd participants from NC participants.

HIGHLIGHTS

National Institutes of Health Toolbox Odor Identification Test (NIHTB-OIT) discriminated normal controls from mild cognitive impairment. NIHTB-OIT discriminated normal controls from Alzheimer's disease dementia. Rate of olfactory decline with age was similar across all diagnostic categories. NIHTB-OIT scores were lower in participants with positive Alzheimer's biomarker tests. NIHTB-OIT scores did not differ based on APOE genotype.

Olfactory Dysfunction in Children: A Scoping Review

OBJECTIVE

Olfactory disorders are well-studied in the adult population, however, there is a paucity of literature characterizing olfactory dysfunction in pediatric patients. The purpose of this scoping review was to identify known causes of olfactory loss in pediatric populations, clarify the extent of use and validity of smell tests, and summarize current therapies for olfactory loss.

DATA SOURCES

PubMed, Ovid MEDLINE, and Web of Science.

REVIEW METHODS

Databases were systematically searched in September 2020. Two independent reviewers conducted the title and abstract screen, followed by review of full-texts for inclusion based on preset inclusion and exclusion criteria. Extracted data included study type, age/age-range of participants, gender, radiological evidence of olfactory dysfunction, types and results of smell tests used, etiology of olfactory loss, and therapies employed for olfactory loss.

RESULTS

A total of 103 articles (n = 1654) were eligible for final data extraction. The University of Pennsylvania Smell Identification Test was used most frequently for smell testing (21% of studies). In total, 45 causes of olfactory dysfunction have been elucidated by this study: 22 congenital and 23 acquired. Few therapies were described, and all were specific to the etiology of olfactory loss.

CONCLUSION

Olfactory dysfunction has a wide range of etiologies in the pediatric population, and clinicians should have a diagnostic algorithm for how to identify a cause should they encounter it in practice. If no etiology can be identified, education around safety should be provided to both the patient and their caregivers.

Acute Taste Dysfunction in Oropharyngeal Cancer Patients after Transoral Robotic Surgery

OBJECTIVES

To compare taste changes after transoral robotic surgery (TORS) to taste changes in healthy controls.

METHODS

Oropharyngeal cancer patients receiving TORS and healthy controls were recruited. Participants underwent posterolateral and whole-mouth psychophysical taste testing (identification, intensity, and hedonics) at baseline and at 2 weeks postoperatively (patients) or follow-up (controls). Surgeons reported suspension time and glossopharyngeal nerve injury (GNI) based on the identification and sacrifice of the nerve. A Clinical Global Impression (CGI) of taste symptoms was completed at each session ("My sense of taste bothers me" on a 5-point scale from Never [1] to Always [5]). A taste disorder (TD) was a CGI of 3 (Sometimes) or worse. Within-subject changes in CGI and psychophysical scores were computed. "Worsened taste" was a CGI increase by ≥1 point at follow-up.

RESULTS

Of 69 participants, most (33/37 tumor, 31/32 controls) had normal baseline taste (CGI < 3). 14/33 (42%) TORS patients and no controls developed new TDs at follow-up. More smokers (7/9) had worsened taste than nonsmokers (19/60, difference = 46% [95% CI 16%-76%]). More patients without GNI (6/22) than with GNI (0/15) had postoperative phantogeusia (difference = 27% [95% CI 9-45%]). Tumor-ipsilateral taste identification (TI) decreased more in patients (-11.3%) than controls (0.8%, difference = 12.2% [95% CI 5.0-19.3%]). Suspension time was not associated with worsened taste symptoms or psychophysical changes.

CONCLUSIONS

Patient-reported taste changes after TORS are frequent. Compared to healthy controls, TORS patients have decreased tumor-ipsilateral TI. Suspension time and GNI are unlikely to cause symptomatic TDs. Further investigations of the etiology and long-term symptom burden of TORS-associated TDs will aid in the management of oropharyngeal cancer patients.

LEVEL OF EVIDENCE

3 (non-randomized controlled cohort study) Laryngoscope, 133:3520-3528, 2023.

More spice, less salt: How capsaicin affects liking for and perceived saltiness of foods in people with smell loss

People who lose their sense of smell self-report consuming more salt to compensate for a lack of flavor and enhance eating enjoyment. However, this may contribute to excess sodium intake. Capsaicin may help increase salt taste intensity and eating enjoyment in people with smell loss, but this has not been studied in this population. The purpose of this study was to determine 1) whether salt intake in those with smell loss differs from population averages, 2) whether capsaicin increases flavor and salt taste intensity, and 3) if adding spice to foods increases liking in individuals with smell loss. Thirty-three participants 18-65 years old with confirmed smell loss for at least 12 weeks completed two sets of replicate test sessions (four total). In two sessions participants rated overall flavor intensity, taste qualities' intensities, spicy intensity, and liking for model tomato soups with low or regular sodium content and three levels of capsaicin (none, low, or moderate). In the other two sessions, participants rated the same sensory attributes for model food samples with three levels of added spice (none, low, or moderate). 24-hour urine samples were collected to determine sodium intake. Results indicate that although sodium intake is higher than recommended (<2300 mg/day) in those with smell loss (2893 ± 258 mg/day), they do not consume more sodium than population averages (3039 ± 100 mg/day; p = 0.3). Adding low and moderate amounts of capsaicin to a model tomato soup increased the intensity of overall flavor (p < 0.001) and saltiness (p = 0.004) compared to a model tomato soup without capsaicin. However, capsaicin's effect on liking differed by food type. Thus, capsaicin can improve flavor, salt taste intensity, and eating enjoyment in people with smell loss.

Patient Insights into the Diagnosis of Smell and Taste Disorders in the United States

OBJECTIVES

Diagnosis of smell/taste dysfunction is necessary for appropriate medical care. This study examines factors affecting testing and diagnosis of smell/taste disorders .

METHODS

The online USA Smell and Taste Patient Survey was made available to US patients with smell/taste disorders between April 6-20, 2022. 4,728 respondents were included.

RESULTS

1,791 (38%) patients reported a documented diagnosis. Patients most often saw family practitioners (34%), otolaryngologists (20%), and Taste/Smell clinics (6%) for smell/taste dysfunction. 64% of patients who went to Taste/Smell clinics received smell testing, followed by 39% of patients who saw otolaryngologists, and 31% of patients who saw family practitioners. Factors associated with increased odds of diagnosis included age (25-39 years (OR 2.97, 95% CI [2.25, 3.95]), 40-60 (OR 3.3, 95% CI [2.56, 4.52]), and >60 (OR 4.25, 95% CI [3.21, 5.67]) vs. 18-24 years), male gender (OR 1.26, 95% CI [1.07, 1.48]), insurance status (private (OR 1.61, 95% CI [1.15, 2.30]) or public (OR 2.03, 95% CI [1.42, 2.95]) vs. uninsured), perception of their family practitioner to be knowledgeable (OR 2.12, 95% CI [1.16, 3.90]), otolaryngologic evaluation (OR 6.17, 95% CI [5.16, 7.38]), and psychophysical smell testing (OR 1.77, 95% CI [1.42, 2.22]).

CONCLUSION

Psychophysical testing, otolaryngologic evaluation, patient assessment of family practitioner knowledge level, insurance, age, and gender are significant factors in obtaining smell/taste dysfunction diagnosis. This study identifies barriers to diagnosis including lack of insurance or access to specialist evaluation and highlights the importance of educating family practitioners in diagnosis and management of patients with smell/taste disorders.

Genetic Variation and Sensory Perception of a Pediatric Formulation of Ibuprofen: Can a Medicine Taste Too Good for Some?

There is wide variation in how individuals perceive the chemosensory attributes of liquid formulations of ibuprofen, encompassing both adults and children. To understand personal variation in the taste and chemesthesis properties of this medicine, and how to measure it, our first scientific strategy centered on utilizing trained adult panelists, due to the complex and time-consuming psychophysical tasks needed at this initial stage. We conducted a double-blind cohort study in which panelists underwent whole-genome-wide genotyping and psychophysically evaluated an over-the-counter pediatric medicine containing ibuprofen. Associations between sensory phenotypes and genetic variation near/within irritant and taste receptor genes were determined. Panelists who experienced the urge to cough or throat sensations found the medicine less palatable and sweet, and more irritating. Perceptions varied with genetic ancestry; panelists of African genetic ancestry had fewer chemesthetic sensations, rating the medicine sweeter, less irritating, and more palatable than did those of European genetic ancestry. We discovered a novel association between TRPA1 rs11988795 and tingling sensations, independent of ancestry. We also determined for the first time that just tasting the medicine allowed predictions of perceptions after swallowing, simplifying future psychophysical studies on diverse populations of different age groups needed to understand genetic, cultural-dietary, and epigenetic factors that influence individual perceptions of palatability and, in turn, adherence and the risk of accidental ingestion.

More spice, less salt: how capsaicin affects liking for and perceived saltiness of foods in people with smell loss

People who lose their sense of smell self-report consuming more salt to compensate for a lack of flavor and enhance eating enjoyment. However, this can contribute to excess sodium intake and a poor diet. Capsaicin may help increase salt taste intensity and eating enjoyment in this population, but this has not been studied. The purpose of this study was to determine 1) whether salt intake in those with smell loss differs from population averages, 2) whether capsaicin increases flavor and salt taste intensity, and 3) if adding spice to foods increases food liking in individuals with smell loss. Participants 18-65 years old with confirmed partial or total smell loss for at least 12 weeks completed two sets of replicate test sessions (four total). In two sessions participants rated overall flavor intensity, taste qualities' intensities, spicy intensity, and liking for model tomato soups with low or regular sodium content and three levels of capsaicin (none, low, or moderate). In the other two sessions, participants rated the same sensory attributes for model food samples with three levels of added spice (none, low, or moderate). 24-hour urine samples were also collected to determine sodium intake. Results indicate that although sodium intake is higher than recommended in those with smell loss (2893 ± 258 mg/day), they do not consume more sodium than population averages. Adding low and moderate amounts of capsaicin to a model tomato soup increased the intensity of overall flavor and saltiness compared to a model tomato soup without capsaicin. However, the effect of capsaicin on liking differed by food type. In conclusion, the addition of capsaicin can improve flavor, salt taste intensity, and eating enjoyment in people with smell loss.

Low to moderate genetic influences on the rapid smell test SCENTinel™

SCENTinel™ - a rapid, inexpensive smell test that measures odor detection, intensity, identification, and pleasantness - was developed for population-wide screening of smell function. SCENTinel™ was previously found to screen for multiple types of smell disorders. However, the effect of genetic variability on SCENTinel™ test performance is unknown, which could affect the test's validity. This study assessed performance of SCENTinel™ in a large group of individuals with a normal sense of smell to determine the test-retest reliability and the heritability of SCENTinel™ test performance. One thousand participants (36 [IQR 26-52] years old, 72% female, 80% white) completed a SCENTinel™ test at the 2021 and 2022 Twins Days Festivals in Twinsburg, OH, and 118 of those completed a SCENTinel™ test on each of the festival's two days. Participants comprised 55% percent monozygotic twins, 13% dizygotic twins, 0.4% triplets, and 36% singletons. We found that 97% of participants passed the SCENTinel™ test. Test-retest reliability ranged from 0.57 to 0.71 for SCENTinel™ subtests. Broad-sense heritability, based on 246 monozygotic and 62 dizygotic twin dyads, was low for odor intensity (r=0.03) and moderate for odor pleasantness (r=0.4). Together, this study suggests that SCENTinel™ is a reliable smell test with only moderate heritability effects, which further supports its utility for population-wide screening for smell function.

Baseline characterization of the ARMADA (Assessing Reliable Measurement in Alzheimer's Disease) study cohorts

INTRODUCTION

The National Institutes of Health (NIH) Toolbox (NIHTB) provides computerized measures of cognition, emotion, sensation, and motor abilities across the lifespan. The ARMADA (Assessing Reliable Measurement in Alzheimer's Disease and Cognitive Aging) study validated the NIHTB in individuals across the cognitive aging spectrum. This article reports the characteristics of our sample of participants.

METHODS

Participants were recruited across nine sites and classified clinically as cognitively normal (NC), with mild cognitive impairment (MCI), or with dementia of the Alzheimer's type (DAT.) They completed the NIHTB at multiple time points and many had at least one Alzheimer's biomarker previously obtained.

RESULTS

Groups differed with respect to dementia severity levels, as anticipated, but were well-matched across many demographic characteristics.

DISCUSSION

The ARMADA study demographics and baseline characteristics provide a suitable sample for validating the NIHTB across the cognitive aging spectrum. Other enriched samples (African American participants, Spanish NIHTB, 85+ years of age) will be reported elsewhere.

HIGHLIGHTS

There is a need for assessments that can detect the early stages of cognitive decline in older adults. The ARMADA (Assessing Reliable Measurement in Alzheimer's Disease and Cognitive Aging) study will validate the National Institutes of Health (NIH) Toolbox across the aging spectrum, including mild cognitive impairment (MCI) and dementia of the Alzheimer's type (DAT). Here we report the characteristics of participants. Groups were well-matched across most demographic characteristics, and clinical characteristics differed as expected. ARMADA study cohorts reflect their respective clinical syndromes for validating the NIH Toolbox.

Examining the Influence of Chemosensation on Laryngeal Health and Disorders

Inhaled airborne stimuli are associated with laryngeal disorders affecting respiration. Clinically, several themes emerged from the literature that point to specific gaps in the understanding and management of these disorders. There is wide variation in the types of airborne stimuli that trigger symptoms, lack of standardization in provocation challenge testing using airborne stimuli, and vague reporting of laryngeal symptoms. Scientifically, evidence exists outside the field of voice science that could prove useful to implement among patients with impaired laryngeal-respiration. To expand this area of expertise, here we provide a thematic overview of relevant evidence and methodological tools from the discipline of chemosensory sciences. This review provides distinctions across the three chemosensory systems of olfaction, trigeminal chemesthesis, and gustation, guidance on selecting and delivering common chemosensory stimuli for clinical testing, and methods of quantifying sensory experiences using principles of human psychophysics. Investigating the science of chemosensation reveals that laryngeal responses to inhaled airborne stimuli have explanations involving physiological mechanisms as well as higher cognitive processing. Fortunately, these findings are consistent with current pharmacological and nonpharmacological interventions for impaired laryngeal-respiration. Based on the close relationships among inhaled airborne stimuli, respiration, and laryngeal function, we propose that new perspectives from chemosensory sciences offer opportunities to improve patient care and target areas of future research.

Proof-of-concept: SCENTinel 1.1 rapidly discriminates COVID-19-related olfactory disorders

It is estimated that 20%-67% of those with COVID-19 develop olfactory disorders, depending on the SARS-CoV-2 variant. However, there is an absence of quick, population-wide olfactory tests to screen for olfactory disorders. The purpose of this study was to provide a proof-of-concept that SCENTinel 1.1, a rapid, inexpensive, population-wide olfactory test, can discriminate between anosmia (total smell loss), hyposmia (reduced sense of smell), parosmia (distorted odor perception), and phantosmia (odor sensation without a source). Participants were mailed a SCENTinel 1.1 test, which measures odor detection, intensity, identification, and pleasantness, using one of 4 possible odors. Those who completed the test (N = 287) were divided into groups based on their self-reported olfactory function: quantitative olfactory disorder only (anosmia or hyposmia, N = 135), qualitative olfactory disorder only (parosmia and/or phantosmia; N = 86), and normosmia (normal sense of smell; N = 66). SCENTinel 1.1 accurately discriminates quantitative olfactory disorders, qualitative olfactory disorders, and normosmia groups. When olfactory disorders were assessed individually, SCENTinel 1.1 discriminates between hyposmia, parosmia, and anosmia. Participants with parosmia rated common odors less pleasant than those without parosmia. We provide proof-of-concept that SCENTinel 1.1, a rapid smell test, can discriminate quantitative and qualitative olfactory disorders, and is the only direct test to rapidly discriminate parosmia.

Skull Base Registries: A Roadmap

Hospitals, payors, and patients increasingly expect us to report our outcomes in more detail and to justify our treatment decisions and costs. Although there are many stakeholders in surgical outcomes, physicians must take the lead role in defining how outcomes are assessed. Skull base lesions interact with surrounding anatomy to produce a complex spectrum of presentations and surgical challenges, requiring a wide variety of surgical approaches. Moreover, many skull base lesions are relatively rare. These factors and others often preclude the use of prospective randomized clinical trials, thus necessitating alternate methods of scientific inquiry. In this paper, we propose a roadmap for implementing a skull base registry, along with expected benefits and challenges.

Proof-of-concept: SCENTinel 1.1 rapidly discriminates COVID-19 related olfactory disorders

It is estimated that 20-67% of those with COVID-19 develop olfactory disorders, depending on the SARS-CoV-2 variant. However, there is an absence of quick, population-wide olfactory tests to screen for olfactory disorders. The purpose of this study was to provide a proof-of-concept that SCENTinel 1.1, a rapid, inexpensive, population-wide olfactory test, can discriminate between anosmia (total smell loss), hyposmia (reduced sense of smell), parosmia (distorted odor perception), and phantosmia (odor sensation without a source). Participants were mailed a SCENTinel 1.1 test, which measures odor detection, intensity, identification, and pleasantness, using one of four possible odors. Those who completed the test (N = 381) were divided into groups based on their self-reported olfactory function: quantitative olfactory disorder (anosmia or hyposmia, N = 135), qualitative olfactory disorder (parosmia and/or phantosmia; N = 86), and normosmia (normal sense of smell; N = 66). SCENTinel 1.1 accurately discriminates quantitative olfactory disorders, qualitative olfactory disorders, and normosmia groups. When olfactory disorders were assessed individually, SCENTinel 1.1 discriminates between hyposmia, parosmia and anosmia. Participants with parosmia rated common odors less pleasant than those without parosmia. We provide proof-of-concept that SCENTinel 1.1, a rapid smell test, can discriminate quantitative and qualitative olfactory disorders, and is the only direct test to rapidly discriminate parosmia.

Effects of SARS-CoV-2 Infection on Attention, Memory, and Sensorimotor Performance

BACKGROUND

Recovery after SARS-CoV-2 infection is extremely variable, with some individuals recovering quickly, and others experiencing persistent long-term symptoms or developing new symptoms after the acute phase of infection, including fatigue, poor concentration, impaired attention, or memory deficits. Many existing studies reporting cognitive deficits associated with SARS-CoV-2 infection are limited by the exclusive use of self-reported measures or a lack of adequate comparison groups.

METHODS

Forty-five participants, ages 18-70, (11 Long-COVID, 14 COVID, and 20 No-COVID) underwent behavioral testing with the NIH Toolbox Neuro-Quality of Life survey and selected psychometric tests, including a flanker interference task and the d2 Test of Attention.

RESULTS

We found greater self-reported anxiety, apathy, fatigue, emotional dyscontrol, sleep disturbance and cognitive dysfunction in COVID compared No-COVID groups. After categorizing COVID patients according to self-reported concentration problems, we observed declining performance patterns in multiple attention measures across No-COVID controls, COVID and Long-COVID groups. COVID participants, compared to No-COVID controls, exhibited worse performance on NIH Toolbox assessments, including the Eriksen Flanker, Nine-Hole Pegboard and Auditory Verbal Learning tests.

CONCLUSION

This study provides convergent evidence that previous SARS-CoV-2 infection is associated with impairments in sustained attention, processing speed, self-reported fatigue and concentration. The finding that some patients have cognitive and visuomotor dysfunction in the absence of self-reported problems suggests that SARS-CoV-2 infection can have unexpected and persistent subclinical consequences.

ARMADA: Assessing reliable measurement in Alzheimer's disease and cognitive aging project methods

INTRODUCTION

Early detection of cognitive decline in older adults is a public health priority. Advancing Reliable Measurement in Alzheimer's Disease and Cognitive Aging (ARMADA), a multisite study, is validating cognition, emotion, motor, and sensory modules of the National Institutes of Health Toolbox for Assessment of Neurological and Behavioral Function (NIHTB) in the aging spectrum from cognitively normal to dementia of the Alzheimer's type (DAT).

METHODS

Participants 65 to 85 years old, in demographic groups racially proportional to the general US population, are recruited in one of three groups to validate the NIHTB: cognitively normal, amnestic mild cognitive impairment (aMCI), or mild DAT. Additional special emphasis cohorts include (1) Blacks in the three clinical groups; (2) Spanish-speakers in the three clinical groups; (3) cognitively normal, population-proportional, over age 85.

DISCUSSION

Longitudinal study will determine whether NIHTB can predict cognitive decline and is associated with Alzheimer's disease biomarkers. Here, we detail the methods for the ARMADA study.

Future Directions for Chemosensory Connectomes: Best Practices and Specific Challenges

Ecological chemosensory stimuli almost always evoke responses in more than one sensory system. Moreover, any sensory processing takes place along a hierarchy of brain regions. So far, the field of chemosensory neuroimaging is dominated by studies that examine the role of brain regions in isolation. However, to completely understand neural processing of chemosensation, we must also examine interactions between regions. In general, the use of connectivity methods has increased in the neuroimaging field, providing important insights to physical sensory processing, such as vision, audition, and touch. A similar trend has been observed in chemosensory neuroimaging, however, these established techniques have largely not been rigorously applied to imaging studies on the chemical senses, leaving network insights overlooked. In this article, we first highlight some recent work in chemosensory connectomics and we summarize different connectomics techniques. Then, we outline specific challenges for chemosensory connectome neuroimaging studies. Finally, we review best practices from the general connectomics and neuroimaging fields. We recommend future studies to develop or use the following methods we perceive as key to improve chemosensory connectomics: (1) optimized study designs, (2) reporting guidelines, (3) consensus on brain parcellations, (4) consortium research, and (5) data sharing.

The Adaptive Olfactory Measure of Threshold (ArOMa-T): A rapid test of olfactory function

PURPOSE

Many widely-used psychophysical tests of olfaction have limitations that can create barriers to adoption outside research settings. For example, tests that measure the ability to identify odors may confound sensory performance with memory recall, verbal ability, and past experience with the odor. Conversely, threshold-based tests typically avoid these issues, but are labor intensive. Additionally, many commercially available olfactory tests are slow and may require a trained administrator, making them impractical for use in a short wellness visit or other broad clinical assessment.

METHODS

We tested the performance of the Adaptive Olfactory Measure of Threshold (ArOMa-T) -- a novel odor detection threshold test that employs an adaptive Bayesian algorithm paired with a disposable odor-delivery card -- in a non-clinical sample of individuals (n=534) at the 2021 Twins Day Festival in Twinsburg, OH.

RESULTS

Participants successfully completed the test in under 3 min with a false alarm rate of 9.6% and a test-retest reliability of 0.61. Odor detection thresholds differed by sex (~3.2-fold) and between the youngest and oldest age groups (~8.7-fold), consistent with prior work. In an exploratory analysis, we failed to observe evidence of detection threshold differences between participants who reported a history of COVID-19 and matched controls who did not. We also found evidence for broad-sense heritability of odor detection thresholds.

CONCLUSION

Together, these data indicate the ArOMa-T can determine odor detection thresholds. The ArOMa-T may be particularly valuable in clinical or field settings where rapid and portable assessment of olfactory function is needed.

International consensus statement on allergy and rhinology: Olfaction

BACKGROUND

The literature regarding clinical olfaction, olfactory loss, and olfactory dysfunction has expanded rapidly over the past two decades, with an exponential rise in the past year. There is substantial variability in the quality of this literature and a need to consolidate and critically review the evidence. It is with that aim that we have gathered experts from around the world to produce this International Consensus on Allergy and Rhinology: Olfaction (ICAR:O).

METHODS

Using previously described methodology, specific topics were developed relating to olfaction. Each topic was assigned a literature review, evidence-based review, or evidence-based review with recommendations format as dictated by available evidence and scope within the ICAR:O document. Following iterative reviews of each topic, the ICAR:O document was integrated and reviewed by all authors for final consensus.

RESULTS

The ICAR:O document reviews nearly 100 separate topics within the realm of olfaction, including diagnosis, epidemiology, disease burden, diagnosis, testing, etiology, treatment, and associated pathologies.

CONCLUSION

This critical review of the existing clinical olfaction literature provides much needed insight and clarity into the evaluation, diagnosis, and treatment of patients with olfactory dysfunction, while also clearly delineating gaps in our knowledge and evidence base that we should investigate further.

Five-item odorant test as an indicator of COVID-19 infection in a general population

Purpose

To analyze the utility of a 5-item odorant test (U-Smell-It™) in determining COVID-19 status in COVID-19 polymerase chain reaction (PCR)-positive and -negative participants.

Methods

Symptoms, COVID-19 status, and 5-item odorant test results were collected from general population COVID-19 testing in Louisiana (n = 1042), and routine COVID-19 screening of healthcare workers in a nursing home in Florida (n = 278) (ClinicalTrials.gov Identifier: NCT04431908).

Results

In the general population COVID-19 testing site, a cutoff point of ≤2 (0, 1, or 2 correct answers out of 5) achieved sensitivity of 40.0% (95% CI: 26.4%–54.8%) and specificity of 89.2% (95% CI: 87.1%–91.1%) in detecting COVID-19 infection. Within this population, analysis of individuals with no self-reported loss of smell/taste and runny/stuffy nose resulted in sensitivity of 38.1% (95% CI: 18.1%–61.6%) and specificity of 92.3% (95% CI: 89.1%–93.4%), while analysis of individuals with self-reported loss of smell/taste and/or runny/stuffy nose resulted in sensitivity of 41.4% (95% CI: 23.5%–61.1%) and specificity of 82.4% (95% CI: 77.7%–86.5%).

Conclusions

The quick turnaround time, low cost, reduced resource requirement, and ease of administering odorant tests provide many advantages as an indicator sign to help flag a molecular diagnostic COVID-19 test with relatively high specificity. Our results suggest that this odorant testing for olfactory dysfunction may be a viable option in pre-screening COVID-19 infection. This tool has the potential to allow for continued monitoring and surveillance, while helping mitigate surges of COVID-19 variants. Further investigation is warranted to observe the extent to which odorant testing might be applied in a serial testing scenario.

The Adaptive Olfactory Measure of Threshold (ArOMa-T): a rapid test of olfactory function

Many widely used psychophysical olfactory tests have limitations that can create barriers to adoption. For example, tests that measure the ability to identify odors may confound sensory performance with memory recall, verbal ability, and prior experience with the odor. Conversely, classic threshold-based tests avoid these issues, but are labor intensive. Additionally, many commercially available tests are slow and may require a trained administrator, making them impractical for use in situations where time is at a premium or self-administration is required. We tested the performance of the Adaptive Olfactory Measure of Threshold (ArOMa-T)-a novel odor detection threshold test that employs an adaptive Bayesian algorithm paired with a disposable odorant delivery card-in a non-clinical sample of individuals (n = 534) at the 2021 Twins Day Festival in Twinsburg, OH. Participants successfully completed the test in under 3 min with a false alarm rate of 7.5% and a test-retest reliability of 0.61. Odor detection thresholds differed by sex (~3.2-fold lower for females) and age (~8.7-fold lower for the youngest versus the oldest age group), consistent with prior studies. In an exploratory analysis, we failed to observe evidence of detection threshold differences between participants who reported a history of COVID-19 and matched controls who did not. We also found evidence for broad-sense heritability of odor detection thresholds. Together, this study suggests the ArOMa-T can determine odor detection thresholds. Additional validation studies are needed to confirm the value of ArOMa-T in clinical or field settings where rapid and portable assessment of olfactory function is needed.

NCS Assessments of the Motor, Sensory, and Physical Health Domains

As part of the National Children's Study (NCS) comprehensive and longitudinal assessment of the health status of the whole child, scientific teams were convened to recommend assessment measures for the NCS. This manuscript documents the work of three scientific teams who focused on the motor, sensory, or the physical health aspects of this assessment. Each domain team offered a value proposition for the importance of their domain to the health outcomes of the developing infant and child. Constructs within each domain were identified and measures of these constructs proposed. Where available extant assessments were identified. Those constructs that were in need of revised or new assessment instruments were identified and described. Recommendations also were made for the age when the assessments should take place.

Final results from a Phase 3, long-term, open-label, repeat-dose safety study of diazepam nasal spray for seizure clusters in patients with epilepsy

Objective

A Phase 3 open‐label safety study (NCT02721069) evaluated long‐term safety of diazepam nasal spray (Valtoco) in patients with epilepsy and frequent seizure clusters.

Methods

Patients were 6–65 years old with diagnosed epilepsy and seizure clusters despite stable antiseizure medications. The treatment period was 12 months, with study visits at Day 30 and every 60 days thereafter, after which patients could elect to continue. Doses were based on age and weight. Seizure and treatment information was recorded in diaries. Treatment‐emergent adverse events (TEAEs), nasal irritation, and olfactory changes were recorded.

Results

Of 163 patients in the safety population, 117 (71.8%) completed the study. Duration of exposure was ≥12 months for 81.6% of patients. There was one death (sudden unexpected death in epilepsy) and one withdrawal owing to a TEAE (major depression), both considered unlikely to be related to treatment. Diazepam nasal spray was administered 4390 times for 3853 seizure clusters, with 485 clusters treated with a second dose within 24 h; 53.4% of patients had monthly average usage of one to two doses, 41.7% two to five doses, and 4.9% more than five doses. No serious TEAEs were considered to be treatment related. TEAEs possibly or probably related to treatment (n = 30) were most commonly nasal discomfort (6.1%); headache (2.5%); and dysgeusia, epistaxis, and somnolence (1.8% each). Only 13 patients (7.9%) showed nasal irritation, and there were no relevant olfactory changes. The safety profile of diazepam nasal spray was generally similar across subgroups based on age, monthly usage, concomitant benzodiazepine therapy, or seasonal allergy/rhinitis.

Significance

In this large open‐label safety study, the safety profile of diazepam nasal spray was consistent with the established profile of rectal diazepam, and the high retention rate supports effectiveness in this population. A second dose was used in only 12.6% of seizure clusters.

Assessment of Olfactory Function in Children and Adolescents: An Overview

Valid and reliable tools for assessing olfactory function are necessary for the diagnosis of olfactory dysfunction. Olfactory testing can be challenging in a pediatric population due to shorter attention span, linguistic development, and lower olfactory experience in this age group. The aim of this article is to present an overview about olfactory tests that are suitable for a pediatric population. Publications were included when reporting new developed methods of psychophysical olfactory testing in children or adaptation and applications of existing olfactory tests for a pediatric population. Olfactory tests for all 3 major aspects of olfactory function-olfactory threshold, odor discrimination, and odor identification-were included. Olfactory tests were evaluated regarding test validity, test reliability, normative data, and test availability. The current literature shows that several tests are available to assess olfactory function in children. Especially odor identification abilities in a pediatric population are well examined and understood. Tests for olfactory threshold and odor discrimination are less frequently used. In terms of the abovementioned evaluation criteria, only a few tests met all or 3 of these 4 criteria. Based on the current literature the following tests can be recommended for valid and reliable olfactory testing in children: "U-Sniff" odor identification test, the "Sniffin' Sticks" olfactory threshold test, pBOT-6 olfactory threshold and odor identification test, NIH-Toolbox, and Smell Wheel. Age has to be considered when evaluating olfactory function in children.

Psychosocial, Functional, and Emotional Correlates of Long-Term Opioid Use in Patients with Chronic Back Pain: A Cross-Sectional Case-Control Study

INTRODUCTION

The opiate epidemic has severe medical and social consequences. Opioids are commonly prescribed in patients with chronic pain, and are a main contributor to the opiate epidemic. The adverse effects of long-term opioid usage have been studied primarily in dependence/addiction disorders, but not in chronic pain. Here, we examine the added iatrogenic effects, psychology, and brain morphology of long-term opioid use in matched patients with chronic pain with and without opioid use (case-controlled design).

METHODS

We compared psychosocial, functional, and psychological measures between patients with chronic back pain (CBP) who were managing their pain with or without opioids, thereby controlling for the effect of pain on these outcomes. In addition, we investigated brain morphological differences associated with long-term opioid usage. We recruited 58 patients with CBP, 29 of them on long-term opioids and 29 who did not use opioids, and who were matched in terms of age, sex, pain intensity, and pain duration. Questionnaires were used to assess pain quality, pain psychology, negative and positive emotions, physical, cognitive, sensory, and motor functions, quality of life, and personality traits.

RESULTS

Patients with CBP on opioids displayed more negative emotion, poorer physical function, and more pain interference (p < 0.001), whereas there were no statistical differences in cognitive and motor functions and personality traits. Voxel-based morphometry using structural brain imaging data identified decreased gray matter density of the dorsal paracingulate cortex (family-wise error-corrected p < 0.05) in patients with opioids, which was associated with negative emotion (p = 0.03). Finally, a volumetric analysis of hippocampal subfields identified lower volume of the left presubiculum in patients on opioids (p < 0.001).

CONCLUSION

Long-term opioid use in chronic pain is associated with adverse negative emotion and disabilities, as well as decreased gray matter volumes of specific brain regions.

Consistent safety and tolerability of Valtoco® (diazepam nasal spray) in relationship to usage frequency in patients with seizure clusters: Interim results from a phase 3, long-term, open-label, repeat-dose safety study

Objective

Need for rescue therapy differs among patients with seizure clusters. Diazepam nasal spray is approved to treat seizure clusters in patients with epilepsy ≥6 years of age. This analysis used interim data from a phase 3 safety study to assess safety profile and effectiveness of diazepam nasal spray using average number of doses/month as a proxy measurement.

Methods

This phase 3, open‐label, repeat‐dose, safety study of diazepam nasal spray enrolled patients (6‐65 years) with epilepsy and need of benzodiazepine rescue. Patients were stratified by average number of doses/month (<2, moderate frequency; 2‐5, high frequency; >5, very‐high frequency). Safety was evaluated based on treatment‐emergent adverse events (TEAEs), assessed nasal irritation, and olfaction. The proportion of treatments given as a second dose was used as an exploratory proxy for effectiveness.

Results

Of 175 enrolled patients (data cutoff, October 31, 2019), 158 received ≥1 dose of diazepam nasal spray. Frequency of use was moderate in 43.7% of patients, high in 50.6% of patients, and very high in 5.7% of patients. Patients treated 3397 seizure episodes (moderate frequency, 14.2%; high frequency, 59.9%; very high frequency, 25.8%). Nasal discomfort was the most common treatment‐related TEAE in all groups. No notable changes in nasal irritation or olfaction were observed. Second doses represented only 2.5%, 7.5%, and 17.2% of all doses in the moderate‐, high‐, and very‐high‐frequency groups, respectively. Overall retention rate was 82.9%, without an observed relationship to frequency of use.

Significance

Frequency of dosing diazepam nasal spray had little impact on the safety/tolerability profile across a range of <2 to >5 doses/month. Effectiveness was suggested for all dosing frequencies by the high proportion of seizure clusters not treated with a second dose. These results support the utility, safety profile, and effectiveness of diazepam nasal spray across frequencies of seizure cluster burden.

NIH Workshop Report: sensory nutrition and disease

In November 2019, the NIH held the "Sensory Nutrition and Disease" workshop to challenge multidisciplinary researchers working at the interface of sensory science, food science, psychology, neuroscience, nutrition, and health sciences to explore how chemosensation influences dietary choice and health. This report summarizes deliberations of the workshop, as well as follow-up discussion in the wake of the current pandemic. Three topics were addressed: A) the need to optimize human chemosensory testing and assessment, B) the plasticity of chemosensory systems, and C) the interplay of chemosensory signals, cognitive signals, dietary intake, and metabolism. Several ways to advance sensory nutrition research emerged from the workshop: 1) refining methods to measure chemosensation in large cohort studies and validating measures that reflect perception of complex chemosensations relevant to dietary choice; 2) characterizing interindividual differences in chemosensory function and how they affect ingestive behaviors, health, and disease risk; 3) defining circuit-level organization and function that link and interact with gustatory, olfactory, homeostatic, visceral, and cognitive systems; and 4) discovering new ligands for chemosensory receptors (e.g., those produced by the microbiome) and cataloging cell types expressing these receptors. Several of these priorities were made more urgent by the current pandemic because infection with sudden acute respiratory syndrome coronavirus 2 (SARS-CoV-2) and the ensuing coronavirus disease of 2019 has direct short- and perhaps long-term effects on flavor perception. There is increasing evidence of functional interactions between the chemosensory and nutritional sciences. Better characterization of this interface is expected to yield insights to promote health, mitigate disease risk, and guide nutrition policy.

Clinical assessment of olfactory function

Approximately 5% of the general population is affected by functional anosmia with approximately additional 15% exhibiting decreased olfactory function. Many of these individuals ask for help. Because the subjective rating of olfactory function is biased, assessment of olfactory function is important. Olfactory measurements are needed for patient counseling and the tracking of changes in the sense of smell over time. The present review provides an overview of frequently used psychophysical tests for olfactory function, discusses differences between threshold and suprathreshold aspects of olfactory function, and gives examples on how to apply psychophysical tests.

SCENTinel 1.0: Development of a Rapid Test to Screen for Smell Loss

Commercially available smell tests are primarily used in research or in-depth clinical evaluations and are too costly and time-consuming for population surveillance in health emergencies like COVID-19. To address this need, we developed the SCENTinel 1.0 test, which rapidly evaluates 3 olfactory functions: detection, intensity, and identification. We tested whether self-administering the SCENTinel 1.0 test discriminates between individuals with self-reported smell loss and those with average smell ability (normosmic individuals) and provides performance comparable to the validated and standardized NIH Toolbox Odor Identification Test in normosmic individuals. Using Bayesian linear models and prognostic classification algorithms, we compared the SCENTinel 1.0 performance of a group of self-reported anosmic individuals (N = 111, 47 ± 13 years old, F = 71%) and normosmic individuals (N = 154, 47 ± 14 years old, F = 74%) as well as individuals reporting other smell disorders (such as hyposmia or parosmia; N = 42, 55 ± 10 years old, F = 67%). Ninety-four percent of normosmic individuals met our SCENTinel 1.0 accuracy criteria compared with only 10% of anosmic individuals and 64% of individuals with other smell disorders. Overall performance on SCENTinel 1.0 predicted belonging to the normosmic group better than identification or detection alone (vs. anosmic: AUC = 0.95, specificity = 0.94). Odor intensity provided the best single-feature predictor to classify normosmic individuals. Among normosmic individuals, 92% met the accuracy criteria at both SCENTinel 1.0 and the NIH Toolbox Odor Identification Test. SCENTinel 1.0 is a practical test able to discriminate individuals with smell loss and will likely be useful in many clinical situations, including COVID-19 symptom screening.

Odor identification performance in children aged 3-6 years

BACKGROUND

While valid and reliable olfactory tests have been developed for children aged >5 years, olfactory testing has not systematically been evaluated in younger children. The aim of this study was to evaluate the reliability and validity of the "U-Sniff" odor identification test in children aged 3-6 years.

METHODS

We included 160 healthy children (age range 3-6 years) and 14 congenitally anosmic children. Participants were investigated in two identical sessions. The "U-Sniff" test was used to evaluate olfactory function. A picture identification test (PIT) and the Kasel-Concentration-Task (KKA) were administered to identify factors influencing odor identification performance.

RESULTS

Age significantly influenced odor identification performance, with older children achieving higher scores. PIT and KKA scores correlated positively with odor identification scores. The "U-Sniff" test demonstrated a high test-retest reliability (r₁₆₀ = 0.75, p < 0.001). It was possible to distinguish between healthy and anosmic children by means of "U-Sniff" scores starting at age 4 years with high sensitivity (79-93%) and specificity (88-95%).

CONCLUSIONS

The "U-Sniff" test is feasible for children starting at age 3 years. In children aged ≥4 years, it is a reliable and valid method to distinguish between normal olfactory function and anosmia.

IMPACT

Olfactory testing is reliable and valid starting at an age of 4 years. The study adds a systematic evaluation of olfactory testing in young children. Results of this study are especially interesting for clinicians in the diagnosis of olfactory dysfunction.

SCENTinel 1.0 : development of a rapid test to screen for smell loss

Background

Commercially available smell tests are primarily used in research or in-depth clinical evaluations, but are too costly and lengthy for population surveillance in health emergencies like COVID-19. We developed the SCENTinel 1 . 0 test which rapidly evaluates three olfactory functions (detection, intensity, and identification). We tested whether self-administering the SCENTinel 1 . 0 test discriminates between individuals with smell loss or average smell ability (normosmics), and provides comparable performance as the validated and standardized NIH Toolbox ^® Odor Identification Test in normosmics.

Methods

Using Bayesian linear models and prognostic classification algorithms, we compared the SCENTinel 1 . 0 performance of a group of self-reported anosmics (N=111, 47±13yo, F=71%,) and normosmics (N=154, 47±14yo, F=74%), as well as individuals reporting other smell disorders (e.g., hyposmia, parosmia; N=42, 55±10yo, F=67%).

Results

Ninety-four percent of normosmics met our SCENTinel 1 . 0 accuracy criteria, while only 10% of anosmics and 64% of individuals with other smell disorders did. Overall performance on SCENTinel 1 . 0 predicted belonging to the normosmic group better than identification or detection alone (vs. anosmic: AUC=0.95, Sensitivity=0.72, Specificity=0.94). Odor intensity provided the best single-feature predictor to classify normosmics. Among normosmics, 92% met the accuracy criteria at both SCENTinel 1 . 0 and the NIH Toolbox ^® Odor Identification Test.

Conclusions

SCENTinel 1 . 0 is a practical test able to discriminate individuals with smell loss and is likely to be useful in many clinical situations, including COVID-19 symptom screening.

Identifying Treatments for Taste and Smell Disorders: Gaps and Opportunities

The chemical senses of taste and smell play a vital role in conveying information about ourselves and our environment. Tastes and smells can warn against danger and also contribute to the daily enjoyment of food, friends and family, and our surroundings. Over 12% of the US population is estimated to experience taste and smell (chemosensory) dysfunction. Yet, despite this high prevalence, long-term, effective treatments for these disorders have been largely elusive. Clinical successes in other sensory systems, including hearing and vision, have led to new hope for developments in the treatment of chemosensory disorders. To accelerate cures, we convened the "Identifying Treatments for Taste and Smell Disorders" conference, bringing together basic and translational sensory scientists, health care professionals, and patients to identify gaps in our current understanding of chemosensory dysfunction and next steps in a broad-based research strategy. Their suggestions for high-yield next steps were focused in 3 areas: increasing awareness and research capacity (e.g., patient advocacy), developing and enhancing clinical measures of taste and smell, and supporting new avenues of research into cellular and therapeutic approaches (e.g., developing human chemosensory cell lines, stem cells, and gene therapy approaches). These long-term strategies led to specific suggestions for immediate research priorities that focus on expanding our understanding of specific responses of chemosensory cells and developing valuable assays to identify and document cell development, regeneration, and function. Addressing these high-priority areas should accelerate the development of novel and effective treatments for taste and smell disorders.

The NIH Toolbox: Overview of Development for Use with Hispanic Populations

OBJECTIVE

Hispanics/Latinos are the largest and fastest-growing minority population in the United States. To facilitate appropriate outcome assessment of this expanding population, the NIH Toolbox for Assessment of Neurological and Behavioral Function® (NIH Toolbox®) was developed with particular attention paid to the cultural and linguistic needs of English- and Spanish-speaking Hispanics/Latinos.

METHODS

A Cultural Working Group ensured that all included measures were appropriate for use with Hispanics/Latinos in both English and Spanish. In addition, a Spanish Language Working Group assessed all English-language NIH Toolbox measures for translatability.

RESULTS

Measures were translated following the Functional Assessment of Chronic Illness Therapy (FACIT) translation methodology for instances where language interpretation could impact scores, or a modified version thereof for more simplified translations. The Spanish versions of the NIH Toolbox Cognition Battery language measures (i.e., Picture Vocabulary Test, Oral Reading Recognition Test) were developed independently of their English counterparts.

CONCLUSIONS

The Spanish-language version of the NIH Toolbox provides a much-needed set of tools that can be selected as appropriate to complement existing protocols being conducted with the growing Hispanic/Latino population in the United States.

Pharmacokinetics and safety of VALTOCO (NRL-1; diazepam nasal spray) in patients with epilepsy during seizure (ictal/peri-ictal) and nonseizure (interictal) conditions: A phase 1, open-label study

Objective

To assess pharmacokinetics and safety of diazepam nasal spray (NRL‐1; VALTOCO®) in pediatric and adult patients with epilepsy in seizure and nonseizure states.

Methods

A single dose of diazepam nasal spray (5, 10, 15, or 20 mg based on weight) was administered during each of two conditions (ictal/peri‐ictal and interictal condition) to patients 6‐65 years old with partial or generalized epilepsy with motor seizures or seizures with clear alteration of awareness; a second dose was permitted if needed for persistent seizures. Dosing could be interictal or ictal/peri‐ictal first, with a washout of ≥14 days. Blood samples for pharmacokinetic analysis were taken at prespecified time points. Treatment‐emergent adverse events (TEAEs), sedation, nasal irritation, nasal mucosal pain, and olfactory changes were assessed.

Results

Of 57 patients in the study (mean age = 28.1 years [range = 6‐59], 54.4% female, 80.7% white), 49 were included in the primary pharmacokinetic analyses. Diazepam pharmacokinetic profiles were similar under both conditions, with approximately 2‐hour median time to mean (SD) maximum plasma concentrations of 164 (88) and 189 (110) ng/mL for ictal/peri‐ictal and interictal conditions, respectively; drug exposure during the first 6 hours postdosing was 532 (313) and 615 (368) h•ng/mL, respectively. Seventeen patients (29.8%) reported TEAEs, of whom eight (14%) had treatment‐related TEAEs, with those reported in ≥2 patients being dysgeusia (n = 3, 5.3%) and nasal discomfort (n = 2, 3.5%). One patient had serious TEAEs (recurrent seizures, metabolic encephalopathy), which were deemed unrelated to study treatment. No changes in respiratory rate were observed, nor were there clinically relevant changes in sedation, olfaction, nasal irritation, or acute nasal mucosal pain.

Significance

The epileptic conditions (ictal/peri‐ictal, interictal) had minimal impact on diazepam nasal spray pharmacokinetics in patients with epilepsy. Therefore, diazepam nasal spray can be administered ictally and interictally. Diazepam nasal spray safety was consistent with the profile of diazepam.

Reliability and Validity of the Spanish-Language Version of the NIH Toolbox

The psychometric properties of the English-language NIH Toolbox for Assessment of Neurological and Behavioral Function (NIH Toolbox) have been examined in numerous populations. This study evaluated the reliability and validity of the Spanish-language NIH Toolbox. Participants were children aged 3 to 7 years and adults aged 18 to 85 years who took part in the NIH Toolbox norming study in Spanish. Results supported the internal consistency reliability of included measures. Test-retest reliability was strong for most tests, though it was weaker for the test of olfaction among children and the test of locomotion among adults. Spearman's correlations and general linear models showed Spanish tests were often associated with age, sex, and education. Convergent validity for the two language measures that underwent more intensive development, evaluated via Spearman's correlations with legacy measures, was strong. Results support using the Spanish-language NIH Toolbox to measure neurological and behavioral functioning among Spanish-speaking individuals in the United States.

Evaluation of Pharmacokinetics and Dose Proportionality of Diazepam After Intranasal Administration of NRL-1 to Healthy Volunteers

NRL‐1 is a novel intranasal formulation of diazepam that is being evaluated as rescue medication in patients with epilepsy who experience bouts of increased seizure activity despite stable regimens of antiepileptic drugs. This phase 1, open‐label, randomized, crossover study in healthy adult volunteers consisted of 3 single‐dose periods (5, 10, and 20 mg) followed by a 2‐dose period (2 × 10 mg) with a minimum 28‐day washout between treatments. Blood samples were taken at prespecified time points after intranasal dosing, and bioanalytic analysis of diazepam and nordiazepam was conducted using a validated liquid chromatography–tandem mass spectrometry method. Plasma pharmacokinetic parameters were summarized using descriptive statistics, and dose proportionality (peak concentration [C_max] and area under the plasma concentration–time curve [AUC_0‐∞]) was evaluated based on a power model within a 90%CI of 0.84 to 1.16. Comparisons were also conducted between single 10‐mg dose and multidose (2 × 10 mg) treatments. NRL‐1 administration resulted in rapid diazepam absorption (median time to peak concentration 1.4‐1.5 hours). Plasma concentration‐time profiles showed similar patterns of exposure that appeared to be dose dependent, with C_max of 85.6, 133.6, and 235.3 ng/mL for the 5‐, 10‐, and 20‐mg doses, respectively, although the lower 90%CI for C_max and AUC_0‐∞ exceeded dose proportionality criteria. The coefficient of variation ranged from 59% to 67% for C_max and 48% to 56% for AUC parameters. Dose‐normalized AUC_0–∞ values were comparable between the 2 × 10‐mg and single 10‐mg doses. Treatment‐emergent adverse events were consistent with those expected for diazepam, with transient somnolence the most frequent adverse event (94.4%). These results support NRL‐1 as a potential therapy for managing seizure emergencies.

Normative data for olfactory threshold and odor identification in children and adolescents

OBJECTIVE

Although previous studies have demonstrated the feasibility and validity of olfactory testing in children and adolescents using the "Sniffin' Sticks" odor threshold and "U-Sniff" odor identification test, normative data obtained in a large sample for these tests are missing. Aim of this study was therefore to obtain normative data of healthy children and adolescents for olfactory assessment.

MATERIAL AND METHODS

Olfactory testing was conducted using the "Sniffin' Sticks" olfactory threshold (THR) and the 12-item "U-Sniff" odor identification (ID) test. The data were collected from 490 children and adolescents (234 girls, 257 boys) between the age of 6 and 17 years (mean age: 11.2 ± 3.4 years). In line with previous studies, participants were divided into subgroups regarding their age: i) 6-8 years, ii) 9-11 years, iii) 12-14 years and iv) 15-17 years.

RESULTS

All participants were able to perform the task. Neither sex nor age significantly influenced THR. Girls outperformed boys in ID. In addition, the youngest age group scored lower than the three other age groups on the "U-Sniff" odor identification test. Using the 10th percentile to distinguish normosmia from a reduced sense of smell the following values were obtained for the four age groups: i) THR 4.25 points, ID 7 points, ii) THR 5.0 points, ID 9 points, iii) THR 4.75 points, ID 10 points and iv) THR 5.5 points, ID 10 points.

CONCLUSION

The present study provides normative data for olfactory assessment in children and adolescents using both an olfactory threshold and a suprathreshold test to distinguish between normosmia and a reduced sense of smell using the 10th percentile.

Development of an International Odor Identification Test for Children: The Universal Sniff Test

OBJECTIVE

To assess olfactory function in children and to create and validate an odor identification test to diagnose olfactory dysfunction in children, which we called the Universal Sniff (U-Sniff) test.

STUDY DESIGN

This is a multicenter study involving 19 countries. The U-Sniff test was developed in 3 phases including 1760 children age 5-7 years. Phase 1: identification of potentially recognizable odors; phase 2: selection of odorants for the odor identification test; and phase 3: evaluation of the test and acquisition of normative data. Test-retest reliability was evaluated in a subgroup of children (n = 27), and the test was validated using children with congenital anosmia (n = 14).

RESULTS

Twelve odors were familiar to children and, therefore, included in the U-Sniff test. Children scored a mean ± SD of 9.88 ± 1.80 points out of 12. Normative data was obtained and reported for each country. The U-Sniff test demonstrated a high test-retest reliability (r₂₇ = 0.83, P < .001) and enabled discrimination between normosmia and children with congenital anosmia with a sensitivity of 100% and specificity of 86%.

CONCLUSIONS

The U-Sniff is a valid and reliable method of testing olfaction in children and can be used internationally.

Chemosensory changes and quality of life in patients undergoing hematopoietic stem cell transplantation

PURPOSE

To assess magnitude and characteristics of changes in chemosensory function and quality of life (QOL) for patients receiving hematopoietic stem cell transplantation (HSCT).

METHODS

Patients (aged 18 years and above) scheduled to undergo HSCT at the Seattle Cancer Care Alliance were tested for chemosensory function at three time points: pre-transplant (baseline), 30 ± 5 days (day 30), and 80 ± 5 days (day 80) post-HSCT. Gustatory function was assessed following procedures developed at the Monell-Jefferson Taste and Smell Clinic. Olfactory testing was conducted using the National Institute of Health Toolbox Odor Identification test. QOL was also assessed.

RESULTS

Twenty-nine patients were enrolled in the study between August 2014 and March 2015. Twenty-three patients were included in the analysis, with 16 tested at all three time points (baseline, day 30, and day 80). The primary finding is decreased taste sensitivity for 0.32 M NaCl, 0.0056 M citric acid, and 0.018 M citric acid on day 30 following HSCT. Increased taste sensitivity for 0.32 M sucrose at day 30 was also observed. Taste sensitivity largely recovered by day 80. Olfactory identification scores were unchanged from baseline to day 30. QOL was reduced at day 30 but was restored to an acceptable level of functioning and symptoms by day 80. However, some areas remain impaired.

CONCLUSIONS

Alterations in taste perception were confirmed in the early post-transplant period. This was largely resolved within 2.5 months. No obvious impairments were observed in olfactory function. QOL improved by day 80, though some oral symptoms lingered.

Olfactory perception in children

The ability to smell is important for protection from danger and quality of life, even in children. Although smell loss is rare in children, it can be indicative of some childhood disorders and may be useful for understanding some disorders. This paper reviews the methods and results of behavioral testing olfaction in children, with an emphasis on odor identification, the most common method of assessing the sense of smell in both children and adults. The Pediatric Smell Wheel® is described as a relatively new and powerful tool for testing olfaction in children as young as 4 years of age. An example of its use in testing children with a childhood disorders (autism spectrum disorder, ASD) is provided in addition to a review of the literature on smell function in ASD. It is possible to reliably test sense of smell in children as young as 4 years old and many studies have shown that performance improves with age and can be impacted by childhood disorders. Sex differences in children are briefly discussed. Finally, the paper suggests other methods of testing olfaction in children, such as odor discrimination, that depend less on cognitive factors, which may enhance our understanding of the olfactory capabilities of young children.

Validation of the NIH Toolbox in Individuals with Neurologic Disorders

OBJECTIVE

Individuals with spinal cord injury (SCI), traumatic brain injury (TBI), and stroke experience a variety of neurologically related deficits across multiple domains of function. The NIH Toolbox for the Assessment of Neurological and Behavioral Function (NIHTB) examines motor, sensation, cognition, and emotional functioning. The purpose of this paper is to establish the validity of the NIHTB in individuals with neurologic conditions.

METHODS

Community-dwelling individuals with SCI (n = 209), TBI (n = 184), or stroke (n = 211) completed the NIHTB. Relative risks for impaired performance were examined relative to a matched control groups.

RESULTS

The largest group differences were observed on the Motor domain and for the Fluid Cognition measures. All groups were at increased risk for motor impairment relative to normative standards and matched controls. Fluid cognitive abilities varied across groups such that individuals with stroke and TBI performed more poorly than individuals with SCI; increased relative risks for impaired fluid cognition were seen for individuals in the stroke and TBI groups, but not for those in the SCI group. All three neurologic groups performed normally on most measures in the Sensation Battery, although TBI participants evidenced increased risk for impaired odor identification and the stroke group showed more vision difficulties. On the Emotion Battery, participants in all three groups showed comparably poor psychological well-being, social satisfaction, and self-efficacy, whereas the TBI group also evidenced slightly increased negative affect.

CONCLUSIONS

Data provide support for the validity of the NIHTB in individuals with neurologic conditions.

Olfactory threshold and odor discrimination ability in children - evaluation of a modified "Sniffin' Sticks" test

The clinical diagnostics of olfactory dysfunction in children turns out to be challenging due to low attention span, insufficient linguistic development and lack of odor experiences. Several smell tests have been developed for adults. Most of these examinations take a relatively long time and require a high level of concentration. Therefore, the aim of the current study was to evaluate an odor discrimination and olfactory threshold test using the frequently used “Sniffin’ Sticks” in children and adolescents in a simplified two-alternative-forced-choice version (2AFC) and compare it to the original three-alternative-forced-choice test (3AFC). One-hundred-twenty-one healthy participants aged between 5 and 17 years took part in this study. Within each of the two sessions participants underwent olfactory testing using the modified 2AFC as well as the standard 3AFC method. A better test-retest reliability was achieved using the original 3AFC method compared to the modified 2AFC. This was true for the odor discrimination as well as the olfactory threshold. Age had a significant influence on both tests, which should be considered when testing young children. We discuss these findings with relation to the existing norms and recommend using the 3AFC version due to a better test-retest reliability to measure olfactory function in children.

A Retrospective Cohort Study of Glossopharyngeal Nerve Taste in Children with Recurrent Acute Tonsillitis

Objective To compare glossopharyngeal taste between healthy children and those with recurrent acute tonsillitis. Study Design Retrospective cohort study. Setting Pediatric clinics in a tertiary care medical center and satellite location. Subjects and Methods Smell and taste testing was administered to 80 well children and 64 children with recurrent acute tonsillitis (age range, 6-17 years). Smell testing was performed with the NIH Toolbox Odor Identification Test, with scores based on national averages for age and sex. Validated Taste Strips were placed on the midline of the tongue at the circumvallate papillae in random tastant order and in increasing concentrations to test sweet, salty, sour, and bitter. Ordinal logistic regression was used for multivariate analysis. Results The healthy and tonsillitis groups were similar, with mean ages of 11.3 and 10.8 years ( P = .34), respectively. The tonsillitis group had fewer boys (n = 18 vs 43, P = .002), higher mean body mass index (BMI) percentile (n = 72.2 vs 59.8, P = .01), and more subjects with public or no insurance (n = 24 vs 13, P = .004). Univariate analysis revealed no statistically significant differences in rate of normal overall taste (67.2% vs 60%, P = .39) and in sweet (79.7% vs 82.5%, P = .67), salty (85.9% vs 82.8%, P = .82), sour (64.1% vs 70%, P = .48), and bitter (90.6% vs 86.3%, P = .45). In multivariate analysis, smell ability, sex, BMI percentile, parent BMI, and insurance type did not affect overall taste or sweet, salty, sour, or bitter alone. Conclusion Despite controlling for potential intrinsic (sex, smell, BMI) and extrinsic (parent BMI, insurance type) confounders, there was no statistically significant difference in taste among children with recurrent acute tonsillitis as compared with healthy children.