A meta-analysis to identify factors associated with CPAP machine purchasing in patients with obstructive sleep apnea

Obstructive sleep apnea (OSA) is a common disease and related to several cardiovascular diseases. Treatment with a continuous positive airway pressure (CPAP) machine is effective. However, not all patients with OSA purchase a CPAP machine for personal use. Previous studies showed different predictors of CPAP machine purchasing in patients with OSA. The present study aimed to summarize and identify predictors of CPAP purchasing using meta-analysis. The study was conducted using factors associated with CPAP purchasing in patients with OSA. The types of studies conducted in adult patients with OSA included: Randomized controlled trials, observational studies or descriptive studies comparing factors between those who purchased CPAP and those who did not. A total of five databases, including PubMed, Central database, Scopus, CINAHL Plus and Web of Science, were searched, and the final search was performed on February 8, 2021. Predictors for CPAP purchasing were determined. There were 598 articles from five databases, which met the inclusion criteria. After duplicated article removal, 390 articles were included in the screening process. There were 12 eligible articles for full text evaluation, and of those, eight studies met the study criteria with 1,605 patients from four countries. There were 11 variables that were available for a comparison between those who purchased the CPAP machine and those who did not, and six factors were different between the two groups: Age, years of education, income, smoking, Epworth Sleepiness Scale (ESS) score and apnea hypopnea index/respiratory disturbance index (AHI/RDI). The AHI/RDI was significantly different between the two groups, with the highest mean difference of 10.40 events/h (95% CI, 4.95-15.86). Patients who purchased CPAP were older (1.11 years), had more years of education (0.93 years), smoked more (1.15 pack/year), and had both higher ESS (0.61) and AHI/RDI (10.40) than those who did not purchase CPAP. Additionally, those who purchased CPAP had a 1.47 times higher income than those who did not. In conclusion, specific personal customer and clinical factors were related to the decision of CPAP purchase in patients with OSA.