Respiratory symptoms, sleep-disordered breathing and biomarkers in nocturnal gastroesophageal reflux

• Published in: Respiratory research Vol. 17; no. 1; p. 115
• Main Authors: Emilsson, Össur Ingi, Benediktsdóttir, Bryndís, Ólafsson, Ísleifur, Cook, Elizabeth, Júlíusson, Sigurður, Björnsson, Einar Stefán, Guðlaugsdóttir, Sunna, Guðmundsdóttir, Anna Soffía, Mirgorodskaya, Ekaterina, Ljungström, Evert, Arnardóttir, Erna Sif, Gislason, Thórarinn, Janson, Christer, Olin, Anna-Carin
• Format: Journal Article
• Language: English
• Published: London BioMed Central 20.09.2016; BioMed Central Ltd; Nature Publishing Group
• Subjects: Adult; Aged; airway inflammation; Analysis; apnea-hypopnea index; Asthma; Asthma - diagnosis; Asthma - epidemiology; Asthma - physiopathology; Biomarkers - blood; Breath Tests; Bronchitis; Bronchitis - diagnosis; Bronchitis - epidemiology; Bronchitis - physiopathology; Care and treatment; Case-Control Studies; Circadian Rhythm; Complications and side effects; cough; disease; Disease Progression; Dosage and administration; Exhalation; Exhaled breath; Exhaled breath condensate; Female; Gastroesophageal reflux; Gastroesophageal Reflux - blood; Gastroesophageal Reflux - diagnosis; Gastroesophageal Reflux - epidemiology; Gastroesophageal Reflux - physiopathology; general-population; Health Surveys; health-survey; Humans; Iceland - epidemiology; Influence; Lung - physiopathology; Lungmedicin och allergi; Male; Medicine; Medicine & Public Health; Middle Aged; Nocturnal gastroesophageal reflux; particles; Particles in exhaled air; Pneumology/Respiratory System; Prospective Studies; Pulmonary manifestations of general diseases; Respiration; Respiratory Medicine and Allergy; Respiratory System; Sleep; Sleep apnea syndromes; Sleep Apnea Syndromes - blood; Sleep Apnea Syndromes - diagnosis; Sleep Apnea Syndromes - epidemiology; Sleep Apnea Syndromes - physiopathology; Sleep-disordered breathing; Surface active agents; Time Factors; Illinois; Germany; Particles in exhaled air; Bronchitis; Nocturnal gastroesophageal reflux; Exhaled breath condensate; Sleep-disordered breathing; Asthma
• ISSN: 1465-993X; 1465-9921; 1465-993X
• DOI: 10.1186/s12931-016-0431-7

Background Nocturnal gastroesophageal reflux (nGER) is associated with respiratory symptoms and sleep-disordered breathing (SDB), but the pathogenesis is unclear. We aimed to investigate the association between nGER and respiratory symptoms, exacerbations of respiratory symptoms, SDB and airway inflammation. Methods Participants in the European Community Respiratory Health Survey III in Iceland with nGER symptoms ( n  = 48) and age and gender matched controls ( n  = 42) were studied by questionnaires, exhaled breath condensate (EBC), particles in exhaled air (PEx) measurements, and a home polygraphic study. An exacerbation of respiratory symptoms was defined as an episode of markedly worse respiratory symptoms in the previous 12 months. Results Asthma and bronchitis symptoms were more common among nGER subjects than controls (54 % vs 29 %, p  = 0.01; and 60 % vs 26 %, p  < 0.01, respectively), as were exacerbations of respiratory symptoms (19 % vs 5 %, p  = 0.04). Objectively measured snoring was more common among subjects with nGER than controls (snores per hour of sleep, median (IQR): 177 (79–281) vs 67 (32–182), p  = 0.004). Pepsin (2.5 ng/ml (0.8–5.8) vs 0.8 ng/ml (0.8–3.6), p  = 0.03), substance P (741 pg/ml (626–821) vs 623 pg/ml (562–676), p  < 0.001) and 8-isoprostane (3.0 pg/ml (2.7–3.9) vs 2.6 pg/ml (2.2–2.9), p  = 0.002) in EBC were higher among nGER subjects than controls. Albumin and surfactant protein A in PEx were lower among nGER subjects. These findings were independent of BMI. Conclusion In a general population sample, nGER is associated with symptoms of asthma and bronchitis, as well as exacerbations of respiratory symptoms. Also, nGER is associated with increased respiratory effort during sleep. Biomarker measurements in EBC, PEx and serum indicate that micro-aspiration and neurogenic inflammation are plausible mechanisms.