Prevalence of Gastroesophageal Reflux Disease in Adult Patients with Obstructive Sleep Apnea: A Systematic Review and Meta-Analysis

Introduction: Obstructive sleep apnea (OSA) and gastroesophageal reflux disease (GERD) are prevalent conditions that can lead to significant medical complications. Both are conditions associated with sleep, with nocturnal gastroesophageal reflux (nGER) being one of the most common symptoms of GERD. There is variation in the reported prevalence of GERD in OSA patients across several studies. Thus, a summary of evidence related to disease prevalence from those studies is needed. This systematic review aimed to determine the pooled prevalence of GERD in patients with OSA and the prevalence of nGER, as well as to identify risk factors associated with GERD in adult patients with OSA. Methods: A systematic literature search was conducted in PubMed, the Cochrane Library, Scopus, CINAHL, and Web of Science for studies published up to April 2025. Studies reporting the prevalence of GERD in adult OSA patients were included. Data extraction and bias assessment were performed independently by two reviewers. A meta-analysis using the inverse variance method was used to summarize prevalence data from the included studies. Subgroup analyses were performed based on country and OSA diagnostic criteria. Age, diagnostic methods, body mass index (BMI), and Epworth Sleepiness Scale (ESS) scores were compared between the GERD and non-GERD groups. Results: A total of 33 studies comprising 12,076 patients were included to determine the pooled prevalence of GERD in OSA, which was found to be 34% (95% CI: 25–44, I 2 =98.2%). The prevalence of nGER in OSA was 43% (95% CI: 26–62, I 2 =98.0%). Subgroup analyses revealed that the prevalence of GERD in OSA was highest when GERD was diagnosed using 24-hour pH monitoring, at 56% (95% CI: 44–68). The highest prevalence of GERD was reported in Poland, at 76%. Three factors were significantly associated with GERD in patients with OSA: BMI, ESS score, and female sex. Conclusions: Approximately one-third of OSA patients had GERD. The highest prevalence of GERD was found in studies that used 24-hour pH monitoring. High ESS scores, high BMI, and female sex were associated with the presence of GERD in patients with OSA. The pooled estimates must be interpreted with caution due to high statistical heterogeneity, and the identified risk factors should be viewed with similar caution due to a limited number of studies.