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result(s) for
"Schwab, Richard J."
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Risk factors for sleep-disordered breathing in pregnancy
2014
Rationale Symptoms of sleep-disordered breathing (SDB) are common among pregnant women, and several studies link SDB symptoms with gestational hypertension and preeclampsia. However, few prospective studies objectively measuring SDB during pregnancy have been performed. Objectives We performed a prospective cohort study examining risk factors for third trimester SDB in pregnant women. Measurements and methods 105 pregnant women from the Hospital of the University of Pennsylvania obstetrics practices completed first and third trimester overnight polysomnography studies. We examined whether the number of SDB events per hour of sleep increased during pregnancy. We performed unadjusted and multivariable logistic regression analyses to estimate the effects of usual and pregnancy-specific characteristics on development of third trimester obstructive sleep apnoea (OSA). In secondary analyses, we examined the relationship between objectively measured SDB, hypertensive disorders of pregnancy, and other adverse maternal-fetal outcomes. Main results Mean Apnoea-Hypopnoea Index increased from 2.07 (SD 3.01) events/h at baseline (first trimester) to 3.74 (SD 5.97) in the third trimester (p=0.009). 10.5% of women had OSA in the first trimester. By the third trimester, 26.7% of women had OSA. In multivariable analyses, first trimester body mass index (BMI) and maternal age were significantly associated with third trimester OSA. Conclusions Third trimester OSA is common. Risk factors for third trimester OSA among women without baseline SDB include higher baseline BMI and maternal age.
Journal Article
Understanding the Anatomic Basis for Obstructive Sleep Apnea Syndrome in Adolescents
by
Wang, Stephen
,
Traylor, Joel
,
Bradford, Ruth M.
in
Adenoids - anatomy & histology
,
Adipose Tissue - anatomy & histology
,
Adolescent
2015
Structural risk factors for obstructive sleep apnea syndrome (OSAS) in adolescents have not been well characterized. Because many adolescents with OSAS are obese, we hypothesized that the anatomic OSAS risk factors would be more similar to those in adults than those in children.
To investigate the anatomic risk factors in adolescents with OSAS compared with obese and lean control subjects using magnetic resonance imaging (MRI).
Three groups of adolescents (age range: 12-16 yr) underwent MRI: obese individuals with OSAS (n = 49), obese control subjects (n = 38), and lean control subjects (n = 50).
We studied 137 subjects and found that (1) obese adolescents with OSAS had increased adenotonsillar tissue compared with obese and lean control subjects; (2) obese OSAS adolescents had a smaller nasopharyngeal airway than control subjects; (3) the size of other upper airway soft tissue structures (volume of the tongue, parapharyngeal fat pads, lateral walls, and soft palate) was similar between subjects with OSAS and obese control subjects; (4) although there were no major craniofacial abnormalities in most of the adolescents with OSAS, the ratio of soft tissue to craniofacial space surrounding the airway was increased; and (5) there were sex differences in the pattern of lymphoid proliferation.
Increased size of the pharyngeal lymphoid tissue, rather than enlargement of the upper airway soft tissue structures, is the primary anatomic risk factor for OSAS in obese adolescents. These results are important for clinical decision making and suggest that adenotonsillectomy should be considered as the initial treatment for OSAS in obese adolescents, a group that has poor continuous positive airway pressure adherence and difficulty in achieving weight loss.
Journal Article
Morphometric measurements of intraoral anatomy in children with Beckwith-Wiedemann syndrome: a novel approach
by
Kalish, Jennifer M.
,
Wiemken, Andrew
,
Sussman, Jonathan H.
in
Adolescent
,
Beckwith-Wiedemann syndrome
,
Beckwith-Wiedemann Syndrome - genetics
2024
Background
An easy-to-use tool to objectively measure intraoral anatomy with meaningful clinical correlations may improve care for patients with Beckwith-Wiedemann syndrome (BWS), who commonly have symptomatic macroglossia.
Methods
Children aged 2–17 years with BWS were enrolled between 12/2021 and 01/2024. Digital intraoral photographs with a laser ruler were taken, and morphometric measurements were made using ImageJ software. Relationships between morphometrics and outcomes including BWS clinical score, percentage mosaicism, and incidence of tongue reduction surgery were examined using t-tests and multivariate linear models.
Results
Pharyngeal morphometric measurements were obtained in 49 patients with BWS. Mouth area, width, and height differed significantly across BWS molecular subtypes. Right-to-left tongue width and mouth width were larger in those with loss of methylation at imprinting control region 2 (IC2 LOM) than other BWS variants. Patients with paternal uniparental isodisomy of chromosome 11p15 (pUPD11) had narrower mouths than others. Those with tongue reduction surgery had more tongue ridging than those without surgery. There were correlations between mouth area and BWS clinical score, tongue width and BWS clinical score, and tongue length and percentage mosaicism.
Conclusion
Intraoral morphometric measurements are associated with phenotypic burden in BWS. Tongue morphology varies across the BWS spectrum, with IC2 LOM having wider tongues and mouths, and pUPD11 having narrower mouths. Tongue ridging is more common in those selected for surgery. Intraoral morphometric measurements may be safely obtained at low costs across centers caring for children with BWS or others at risk of upper airway obstruction.
Journal Article
Tirzepatide for the Treatment of Obstructive Sleep Apnea and Obesity
2024
Excess adiposity is a reversible etiologic risk factor for obstructive sleep apnea. In this trial, tirzepatide reduced the apnea–hypopnea index of participants with obstructive sleep apnea and obesity.
Journal Article
Randomised, cOntrolled Multicentre trial of 26 weeks subcutaneous liraglutide (a glucagon-like peptide-1 receptor Agonist), with or without contiNuous positive airway pressure (CPAP), in patients with type 2 diabetes mellitus (T2DM) and obstructive sleep apnoEa (OSA) (ROMANCE): study protocol assessing the effects of weight loss on the apnea–hypnoea index (AHI)
by
Schwab, Richard J
,
Needham, Alexander J
,
Adams, Valerie
in
Antidiabetics
,
Body composition
,
Body mass index
2020
IntroductionObstructive sleep apnoea (OSA) and type 2 diabetes mellitus (T2DM) often occur concurrently, and untreated OSA may potentially amplify the high risk of cardiovascular disease in T2DM. Compliance with continuous positive airway pressure (CPAP), the conventional treatment for OSA, can be poor and considering weight loss is the most effective treatment for OSA. This trial examines whether the glucagon-like peptide-1 receptor agonist liraglutide, a glucose-lowering therapy associated with significant weight loss used in T2DM, can improve the severity and symptoms of OSA.Methods and analysisThis is an outpatient, single-centred, open-labelled, prospective, phase IV randomised controlled trial in a two-by-two factorial design. One hundred and thirty-two patients with newly diagnosed OSA (apnoea–hypopnoea index (AHI) ≥15 events/hour), and existing obesity and T2DM (glycated haemoglobin (HbA1c) ≥47 mmol/mol), will be recruited from diabetes and sleep medicine outpatient clinics in primary and secondary care settings across Liverpool. Patients will be allocated equally, using computer-generated random, permuted blocks of unequal sizes, to each of the four treatment arms for 26 weeks: (i) liraglutide (1.8 mg once per day) alone, (ii) liraglutide 1.8 mg once per day with CPAP, (iii) CPAP alone (conventional care) or (iv) no treatment (control). The primary outcome measure is change in OSA severity, determined by AHI. Secondary outcome measures include effects on glycaemic control (glycated haemoglobin (HbA1c)), body weight and quality of life measures. Exploratory measures include measures of physical activity, MRI-derived measures of regional body composition including fat mass (abdominal subcutaneous, visceral, neck and liver fat) and skeletal muscle mass (cross-sectional analysis of thigh), indices of cardiac function (using transthoracic echocardiography) and endothelial function.Ethical approvalThe study has been approved by the North West Liverpool Central Research Ethics Committee (14/NW/1019) and it is being conducted in accordance with the Declaration of Helsinki and Good Clinical Practice.Trial registration numbersISRCTN16250774. EUDRACT No. 2014-000988-41. UTN U1111-1139-0677.
Journal Article
The association of upper airway anatomy with cognitive test performance: the Multi-Ethnic Study of Atherosclerosis
2023
Background
Numerous upper airway anatomy characteristics are risk factors for sleep apnea, which affects 26% of older Americans, and more severe sleep apnea is associated with cognitive impairment. This study explores the pathophysiology and links between upper airway anatomy, sleep, and cognition.
Methods
Participants in the Multi-Ethnic Study of Atherosclerosis underwent an upper airway MRI, polysomnography to assess sleep measures including the apnea-hypopnea index (AHI) and completed the Cognitive Abilities Screening Instrument (CASI). Two model selection techniques selected from among 67 upper airway measures those that are most strongly associated with CASI score. The associations of selected upper airway measures with AHI, AHI with CASI score, and selected upper airway anatomy measures with CASI score, both alone and after adjustment for AHI, were assessed using linear regression.
Results
Soft palate volume, maxillary divergence, and upper facial height were significantly positively associated with higher CASI score, indicating better cognition. The coefficients were small, with a 1 standard deviation (SD) increase in these variables being associated with a 0.83, 0.75, and 0.70 point higher CASI score, respectively. Additional adjustment for AHI very slightly attenuated these associations. Larger soft palate volume was significantly associated with higher AHI (15% higher AHI (95% CI 2%,28%) per SD). Higher AHI was marginally associated with higher CASI score (0.43 (95% CI 0.01,0.85) per AHI doubling).
Conclusions
Three upper airway measures were weakly but significantly associated with higher global cognitive test performance. Sleep apnea did not appear to be the mechanism through which these upper airway and cognition associations were acting. Further research on the selected upper airway measures is recommended.
Journal Article
Metabolic Activity of the Tongue in Obstructive Sleep Apnea. A Novel Application of FDG Positron Emission Tomography Imaging
by
Keenan, Brendan T.
,
Alavi, Abass
,
Kim, Andrew M.
in
Anesthesia. Intensive care medicine. Transfusions. Cell therapy and gene therapy
,
Biological and medical sciences
,
Body fat
2014
The metabolic activity of the tongue is unknown in patients with obstructive sleep apnea (OSA). Tongue electromyographic (EMG) activity is increased in patients with OSA. This increase in tongue EMG activity is thought to be related to either increased neuromuscular compensation or denervation with subsequent reinnervation of the muscle fibers. Increased glucose uptake in the tongue would support increased neuromuscular compensation, whereas decreased glucose uptake in the tongue would support denervation with subsequent reinnervation of the muscle fibers.
To investigate the metabolic activity of the genioglossus and control upper airway muscles in obese patients with sleep apnea compared with obese control subjects.
Obese subjects with and without OSA underwent a standard overnight sleep study to determine an apnea-hypopnea index. Each subject had a positron emission tomography with [(18)F]-2-fluoro-2-deoxy-D-glucose scan in addition to noncontrast computed tomography or magnetic resonance imaging. Glucose uptake was quantified within upper airway tissues with the standardized uptake value.
We recruited 30 obese control subjects (apnea-hypopnea index, 4.7 ± 3.1 events per hour) and 72 obese patients with sleep apnea (apnea-hypopnea index, 43.5 ± 28.0 events per hour). Independent of age, body mass index, sex, and race, patients with OSA had significantly reduced glucose uptake in the genioglossus (P = 0.03) in comparison with obese normal subjects. No differences in standardized uptake value were found in the control muscles (masseter [P = 0.38] and pterygoid [P = 0.70]) and subcutaneous fat deposits (neck [P = 0.44] and submental [P = 0.95]) between patients with OSA and control subjects.
There was significantly reduced glucose uptake in the genioglossus of patients with sleep apnea in comparison with obese normal subjects with [(18)F]-2-fluoro-2-deoxy-D-glucose positron emission tomography imaging. The reduction in glucose uptake was likely secondary to alterations in tongue muscle fiber-type or secondary to chronic denervation. The reduced glucose uptake argues against the neuromuscular compensation hypothesis explaining the increase in tongue EMG activity in obese patients with OSA.
Journal Article
Sleep in the Intensive Care Unit
2015
Sleep is an important physiologic process, and lack of sleep is associated with a host of adverse outcomes. Basic and clinical research has documented the important role circadian rhythm plays in biologic function. Critical illness is a time of extreme vulnerability for patients, and the important role sleep may play in recovery for intensive care unit (ICU) patients is just beginning to be explored. This concise clinical review focuses on the current state of research examining sleep in critical illness. We discuss sleep and circadian rhythm abnormalities that occur in ICU patients and the challenges to measuring alterations in circadian rhythm in critical illness and review methods to measure sleep in the ICU, including polysomnography, actigraphy, and questionnaires. We discuss data on the impact of potentially modifiable disruptors to patient sleep, such as noise, light, and patient care activities, and report on potential methods to improve sleep in the setting of critical illness. Finally, we review the latest literature on sleep disturbances that persist or develop after critical illness.
Journal Article
Altered Upper Airway and Soft Tissue Structures in the New Zealand Obese Mouse
by
Maislin, Greg
,
Schwab, Richard J
,
Brennick, Michael J
in
Anesthesia. Intensive care medicine. Transfusions. Cell therapy and gene therapy
,
Animals
,
Biological and medical sciences
2009
The effect of obesity on upper airway soft tissue structure and size was examined in the New Zealand Obese (NZO) mouse and in a control lean mouse, the New Zealand White (NZW).
We hypothesized that the NZO mouse has increased volume of neck fat and upper airway soft tissues and decreased pharyngeal airway caliber.
Pharyngeal airway size, volume of the upper airway soft tissue structures, and distribution of fat in the neck and body were measured using magnetic resonance imaging (MRI). Dynamic MRI was used to examine the differences in upper airway caliber between inspiration and expiration in NZO versus NZW mice.
The data support the hypothesis that, in obese NZO versus lean NZW mice, airway caliber was significantly smaller (P < 0.03), with greater parapharyngeal fat pad volumes (P < 0.0001) and a greater volume of other upper airway soft tissue structures (tongue, P = 0.003; lateral pharyngeal walls, P = 0.01; soft palate, P = 0.02). Dynamic MRI showed that the airway of the obese NZO mouse dilated during inspiration, whereas in the lean NZW mouse, the upper airway was reduced in size during inspiration.
In addition to the increased volume of pharyngeal soft tissue structures, direct fat deposits within the tongue may contribute to airway compromise in obesity. Pharyngeal airway dilation during inspiration in NZO mice compared with narrowing in NZW mice suggests that airway compromise in obese mice may lead to muscle activation to defend upper airway patency during inspiration.
Journal Article
Recognizable clinical subtypes of obstructive sleep apnea across international sleep centers: a cluster analysis
by
Prochnow, Lisa Kristin
,
Keenan, Brendan T
,
Tufik, Sergio
in
Cluster analysis
,
Editor's Choice
,
Sleep apnea
2018
Abstract
Study Objectives
A recent study of patients with moderate–severe obstructive sleep apnea (OSA) in Iceland identified three clinical clusters based on symptoms and comorbidities. We sought to verify this finding in a new cohort in Iceland and examine the generalizability of OSA clusters in an international ethnically diverse cohort.
Methods
Using data on 972 patients with moderate–severe OSA (apnea–hypopnea index [AHI] ≥ 15 events per hour) recruited from the Sleep Apnea Global Interdisciplinary Consortium (SAGIC), we performed a latent class analysis of 18 self-reported symptom variables, hypertension, cardiovascular disease, and diabetes.
Results
The original OSA clusters of disturbed sleep, minimally symptomatic, and excessively sleepy replicated among 215 SAGIC patients from Iceland. These clusters also generalized to 757 patients from five other countries. The three clusters had similar average AHI values in both Iceland and the international samples, suggesting clusters are not driven by OSA severity; differences in age, gender, and body mass index were also generally small. Within the international sample, the three original clusters were expanded to five optimal clusters: three were similar to those in Iceland (labeled disturbed sleep, minimal symptoms, and upper airway symptoms with sleepiness) and two were new, less symptomatic clusters (labeled upper airway symptoms dominant and sleepiness dominant). The five clusters showed differences in demographics and AHI, although all were middle-aged (44.6–54.5 years), obese (30.6–35.9 kg/m2), and had severe OSA (42.0–51.4 events per hour) on average.
Conclusions
Results confirm and extend previously identified clinical clusters in OSA. These clusters provide an opportunity for a more personalized approach to the management of OSA.
Journal Article