Psychometric Properties of Obstructive Sleep Apnea Screening Measures in Patients Referred to a Sleep Clinic

Background: Obstructive Sleep Apnea (OSA) contributes to all-cause and cardiac mortality. There are no current guidelines for OSA screening in outpatient settings. An American Academy of Sleep Medicine task force is focusing on improving detection and categorization of OSA symptoms and severity to promote screening, assessment, and diagnosis of the disorder. The purpose of this study was to identify the psychometric properties of three self-report OSA screening measures (Berlin, Epworth Sleepiness Scale (ESS), STOP Bang) and an objective portable sleep monitor (PSM) compared to apnea-hypopnea index (AHI) levels (≥5, ≥ 15, and ≥ 30) from polysomnogram (PSG). Methods: A methodological design was used. Patients referred to a sleep specialist for an OSA consultation were recruited and enrolled at initial sleep evaluation. Participants completed the three OSA self-report screening measures and those participants who met inclusion criteria were sent home with a PSM for one night measurement. Automatic scoring was used. PSGs were ordered by the physician and AHI results were obtained from the medical record. Results: Participants (N=170) were enrolled (88 male, 82 female; age 54.5, SD 5.0 years). Almost all participants completed the self-report OSA screening measures, approximately half completed PSM measurement, and the majority completed laboratory PSG. The STOP Bang had the highest levels of sensitivity; the ESS had the lowest. The ESS had the highest specificity and reliability level. The PSM measure had the highest positive predictive value (PPV). The PSM measure had the strongest psychometric properties of the screening measures. Conclusions: The STOP Bang was the preferred self-report OSA screening measure because of high sensitivity levels. A positive STOP Bang warrants assessment for OSA. The ESS is the least desirable screening measure. If a patient qualifies, further screening with a PSM is indicated. PSM measurement consistently predicted the presence of OSA but at the expense of low sensitivity at AHI levels ≥ 30. PSM results can guide the referral process from primary or specialty clinicians to sleep specialist

The Conserved G-Protein Coupled Receptor FSHR-1 Regulates Protective Host Responses to Infection and Oxidative Stress

The innate immune system’s ability to sense an infection is critical so that it can rapidly respond if pathogenic microorganisms threaten the host, but otherwise maintain a quiescent baseline state to avoid causing damage to the host or to commensal microorganisms. One important mechanism for discriminating between pathogenic and non-pathogenic bacteria is the recognition of cellular damage caused by a pathogen during the course of infection. InCaenorhabditis elegans, the conserved G-protein coupled receptor FSHR-1 is an important constituent of the innate immune response. FSHR-1 activates the expression of antimicrobial infection response genes in infected worms and delays accumulation of the ingested pathogenPseudomonas aeruginosa. FSHR-1 is central not only to the worm’s survival of infection by multiple pathogens, but also to the worm’s survival of xenobiotic cadmium and oxidative stresses. Infected worms produce reactive oxygen species to fight off the pathogens; FSHR-1 is required at the site of infection for the expression of detoxifying genes that protect the host from collateral damage caused by this defense response. Finally, the FSHR-1 pathway is important for the ability of worms to discriminate pathogenic from benign bacteria and subsequently initiate an aversive learning program that promotes selective pathogen avoidance

Sleep Disordered Breathing Screening in Hospitalized Patients with COPD Using Overnight Oximetry and End-Tidal Carbon Dioxide Monitoring: A Feasibility Study

Chronic obstructive pulmonary disease (COPD) and sleep apnea are overlap syndromes and cause an increased systemic inflammatory response, a weakened immune system, poor cognition, and physical inactivity in addition to COPD patients’ comorbid factors causing an overall decreased functional status. Feasibility testing of physiologic measures is needed to promote more accurate screening of sleep-disordered breathing in patients with COPD. This study hypothesizes more effective screening with utilization of overnight oximetry and end-tidal carbon dioxide level monitoring to detect sleep-disordered breathing. This descriptive study will test the feasibility of completing OSA and central sleep apnea screening in hospitalized patients with COPD who have not been diagnosed with a sleep-related breathing disorder. The aim of this study is to evaluate the feasibility of study a) enrollment (recruitment, efficiency, attrition, problems), b) data collection (technology transfer of data, instruments, time required, missing data), and c) clinical data collection from electronic medical record (inpatient and private practice settings). The Chronic Disease Self-Management Theory by Dr. Katie Lorig was utilized as the theoretical framework for this study to incorporate self-management in treatment of these two chronic disorders. This study looks at participants (N=10) who were recruited from Bryan Health in Lincoln, NE and followed post-discharge at Nebraska Pulmonary Specialties, LLC. Following completion of self-reported measures, patients will have overnight oximetry and end-tidal CO2 measured 1-2 days prior to discharge. Study information will be given to their providers at Nebraska Pulmonary Specialties and sleep study data will be obtained if ordered. Descriptive statistics will be completed to evaluate the feasibility of the study after completion. Recruitment and enrollment are underway and results are pending.https://digitalcommons.unmc.edu/surp2021/1041/thumbnail.jp

The Colors of Dwarf Elliptical Galaxy Globular Cluster Systems, Nuclei and Stellar Halos

We present the results of a Hubble Space Telescope WFPC2 F555W and F814W survey of 69 dwarf elliptical galaxies (dEs) in the Virgo and Fornax Clusters and Leo Group. The $V-I$ colors of the dE globular clusters, nuclei, and underlying field star populations are used to trace the dE star-formation histories. We find that the dE globular cluster candidates are as blue as the metal-poor globular clusters of the Milky Way. The observed correlation of the dE globular cluster systems' $V-I$ color with the luminosity of the host dE is strong evidence that the globular clusters were formed within the the halos of dEs and do not have a pre-galactic origin. Assuming the majority of dE clusters are old, the mean globular cluster color- host galaxy luminosity correlation implies a cluster metallicity $-$ galaxy luminosity relation of $Z_{GC} \propto L_B^{0.22 \pm 0.05}$, which is significantly shallower than the field star metallicity - host galaxy luminosity relationship observed in Local Group dwarfs ($Z_{FS} \propto L^{0.4}$). The dE stellar envelopes are $0.1-0.2$ magnitudes redder in $V-I$ than their globular clusters and nuclei. This color offset implies separate star-formation episodes within the dEs for the clusters and field stars, while the very blue colors of two dE nuclei trace a third star-formation event in those dEs less than a Gyr ago.Comment: 39 pages, including 5 tables and 10 figures; accepted by the Astrophysical Journa

Methodological strategies in using home sleep apnea testing in research and practice

Purpose Home sleep apnea testing (HSAT) has increased due to improvements in technology, accessibility, and changes in third party reimbursement requirements. Research studies using HSAT have not consistently reported procedures and methodological challenges. This paper had two objectives: (1) summarize the literature on use of HSAT in research of adults and (2) identify methodological strategies to use in research and practice to standardize HSAT procedures and information. Methods Search strategy included studies of participants undergoing sleep testing for OSA using HSAT. MEDLINE via PubMed, CINAHL, and Embase with the following search terms: “polysomnography,” “home,” “level III,” “obstructive sleep apnea,” and “out of center testing.” Results Research articles that met inclusion criteria (n = 34) inconsistently reported methods and methodological challenges in terms of: (a) participant sampling; (b) instrumentation issues; (c) clinical variables; (d) data processing; and (e) patient acceptability. Ten methodological strategies were identified for adoption when using HSAT in research and practice. Conclusions Future studies need to address the methodological challenges summarized in this paper as well as identify and report consistent HSAT procedures and information

Obesity‐Related Hormones in Low‐Income Preschool‐Age Children: Implications for School Readiness

Mechanisms underlying socioeconomic disparities in school readiness and health outcomes, particularly obesity, among preschool‐aged children are complex and poorly understood. Obesity can induce changes in proteins in the circulation that contribute to the negative impact of obesity on health; such changes may relate to cognitive and emotion regulation skills important for school readiness. We investigated obesity‐related hormones, body mass index ( BMI ), and school readiness in a pilot study of low‐income preschoolers attending Head Start (participating in a larger parent study). We found that the adipokine leptin was related to preschoolers' BMI z ‐score, the appetite‐regulating hormones ghrelin and glucagon‐like peptide 1 ( GLP ‐1), and pro‐inflammatory cytokines typically associated with early life stress; and that some of these obesity‐related biomarkers were in turn related to emotion regulation. Future work should evaluate how obesity may affect multiple domains of development, and consider modeling common physiological pathways related to stress, health, and school readiness.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/101799/1/mbe12034.pd

KING OF THE HILL? HOW BIOTIC INTERACTIONS AFFECT BIOGEOGRAPHICAL PATTERN AND SPECIES RESPONSES TO CLIMATE CHANGE

As climate has warmed, many species have moved up mountains as physiological limits to their distributions have ameliorated. These distribution shifts are creating novel communities, begging the question: What happens to species at the tops of mountains as potential antagonists encroach upwards? Theory predicts that upward migrations will cause range contractions for high-elevation species because of novel interactions with encroaching antagonists. My dissertation work is one of the most comprehensive tests of this question to date, using a combination of ecological niche modeling (ENM), experiments, and demographic and trait-based modeling approaches. I created novel ENMs that suggest context-dependency of biotic interactions, where predictions of biotic interactions change from positive to negative over environmental gradients, is common over elevation gradients. Additionally, ENMs suggested the current focus on plant-plant interactions in niche modeling targets the most important biotic interaction for many species. I then constructed space-for-time experiments that transplanted alpine species into novel low elevation plant and mammal communities expected to encroach upwards, as well as into their native high elevation communities. Plant competition was manipulated by vegetation removals and mammals were excluded in a separate factorial experiment using below- and aboveground fencing. In both experiments, low elevation plant and mammal communities suppressed growth of alpine species to a greater extent than those antagonists found in their home range. However, demographic models suggested that environmental factors (e.g. temperature) other than novel plant and mammal communities are more consequential for determining population fate. The experiments validated a novel trait-based model of competitive interactions that can be broadly applied to other systems and conservation needs. My dissertation work found that alpine plants are unlikely to remain “king of the hill” under climate change, in part due to the upward encroachment of novel competitors and intensification of herbivore pressure

Lymph node topology dictates T cell migration behavior

Adaptive immunity is initiated by T cell recognition of foreign peptides presented on dendritic cells (DCs) by major histocompatibility molecules. These interactions take place in secondary lymphoid tissues, such as lymph nodes (LNs) and spleen, and hence the anatomical structure of these tissues plays a crucial role in the development of immune responses. Two-photon microscopy (2PM) imaging in LNs suggests that T cells walk in a consistent direction for several minutes, pause briefly with a regular period, and then take off in a new, random direction. Here, we construct a spatially explicit model of T cell and DC migration in LNs and show that all dynamical properties of T cells could be a consequence of the densely packed LN environment. By means of 2PM experiments, we confirm that the large velocity fluctuations of T cells are indeed environmentally determined rather than resulting from an intrinsic motility program. Our simulations further predict that T cells self-organize into microscopically small, highly dynamic streams. We present experimental evidence for the presence of such turbulent streams in LNs. Finally, the model allows us to estimate the scanning rates of DCs (2,000 different T cells per hour) and T cells (100 different DCs per hour)