Novel non-invasive assessment of upper airway inflammation in obstructive sleep apnea using positron emission tomography/magnetic resonance imaging.

PURPOSE: To develop a novel non-invasive technique to quantify upper airway inflammation using positron emission tomography/magnetic resonance imaging (PET/MRI) in patients with obstructive sleep apnea (OSA). METHODS: Patients with treatment naïve moderate-to-severe OSA underwent [18F]-fluoro-2-deoxy-D-glucose (FDG) PET/MRI. Three readers independently performed tracings of the pharyngeal soft tissue on MRI. Standardized uptake values (SUV) were generated from region of interest (ROI) tracings on corresponding PET images. Background SUV was measured from the sternocleidomastoid muscle. SUV and target-to-background (TBR) were compared across readers using intraclass correlation coefficient (ICC) analyses. SUV from individual image slices were compared between each reader using Bland-Altman plots and Pearson correlation coefficients. All tracings were repeated by one reader for assessment of intra-reader reliability. RESULTS: Five participants completed our imaging protocol and analysis. Median age, body mass index, and apnea-hypopnea index were 41 years (IQR 40.5-68.5), 32.7 kg/m2 (IQR 28.1-38.1), and 30.7 event per hour (IQR 19.5-48.1), respectively. The highest metabolic activity regions were consistently localized to palatine or lingual tonsil adjacent mucosa. Twenty-five ICC met criteria for excellent agreement. The remaining three were TBR measurements which met criteria for good agreement. Head-to-head comparisons revealed strong correlation between each reader. CONCLUSIONS: Our novel imaging technique demonstrated reliable quantification of upper airway FDG avidity. This technology has implications for future work exploring local airway inflammation in individuals with OSA and exposure to pollutants. It may also serve as an assessment tool for response to OSA therapies.

Self-reported sleep duration is associated with time in work physical activity but not transportation or leisure physical activity among Hispanic/Latino adults in the U.S.: results from the Hispanic Community Health Study/Study of Latinos.

OBJECTIVES: The objective of this study is to test the hypothesis that short sleep duration is associated with fewer minutes of transportation, work, and leisure physical activity (PA). DESIGN: This is a cross-sectional study conducted from 2008 to 2011. SETTING: The study setting included four sites across the U.S. (Bronx, NY; Chicago, IL; Miami, FL; San Diego, CA). PARTICIPANTS: A total of 14,653 Hispanic/Latino adults aged 18-74 years were enrolled as participants for the study. MEASUREMENTS: Respondents reported sleep duration and transportation (including walking and cycling), work (including volunteering, paid work, and household chores), and leisure (including sports) PA domains and sociodemographic characteristics, other sleep characteristics, cardiometabolic health, health behaviors, and depressive symptoms. RESULTS: In analyses weighted to reflect the Hispanic/Latino population of the four cities sampled, 61% had sleep duration 7-9 hours, 19% each had sleep duration < 7 hours and > 9 hours. Those sleeping < 7 hours spent 106 minutes/day in work-related PA, compared with those who spent fewer than 40 minutes/day in transportation-related or leisure-related PA. Sleep duration < 7 hours was associated with 26 minutes more in work-related PA (95% confidence interval [CI]: 16.7, 36.0), compared with sleep duration of 7-9 hours, adjusting for age and sex. Results were similar in employed respondents only, adjusting for occupation class and shift work frequency. Sleep duration was not associated with transportation-related or leisure-related PA. CONCLUSIONS: Short sleep duration is associated with more work-related PA, both in the overall sample and among those employed. Individuals with higher work-related PA may face multiple demands and stressors that negatively influence sleep duration.