Positive airway pressure treatment affects respiratory symptoms and gastro-oesophageal reflux: the Icelandic Sleep Apnea Cohort Study

Abstract

AimTo study the effect of positive airway pressure (PAP) treatment on nocturnal gastroesophageal reflux (nGER) and respiratory symptoms among clinical OSA patients.Methods822 newly diagnosed patients with OSA referred for PAP treatment were recruited. 732 subjects had a 2-year follow-up visit with CPAP compliance data collected (366 full PAP users, 366 partial/non-PAP users). They answered questionnaires, including reporting of nGER, sleep and respiratory symptoms, and general health. Patients with nGER symptoms once a week or more were defined as “with nGER”. Those without nGER symptoms and nGER medication were defined as “no nGER”. Others were defined as “possible nGER”.ResultsPAP treatment among full users resulted in a decreased presence of nGER (adjusted odds ratio (OR) [95% CI]: 0.58 [0.40–0.86]) and wheezing (0.56 [0.35–0.88]) at two-year follow-up, compared with partial/non-PAP users. Decrease in nGER, both among full- and partial/non-users of PAP treatment, associated with a decrease in productive morning cough (4.70 [2.22–9.99]) and a decrease in chronic bronchitis (3.86 [1.74–8.58]), but not decreased wheezing (0.90 [0.39–2.08]). A mediation analysis found that PAP treatment directly led to a decrease in wheezing, not mediated through nGER. Conversely, PAP treatment decreased productive cough mediated through a decrease in nGER.ConclusionIn an unselected group of OSA patients, PAP treatment for two years is associated with a decrease in nGER and respiratory symptoms. The PAP treatment itself associates with less wheezing. A decrease in nGER by PAP treatment is associated with a decrease in productive cough.