A systematic review on prevalence and risk factors associated with treatment- emergent central sleep apnea

INTRODUCTION: Treatment-emergent central sleep apnea (TECSA) is the appearance of central apneas and hypopneas after significant resolution of the obstructive events has been attained using positive airway pressure (PAP) therapy. The aim of the study was to determine the prevalence of TECSA and to understand what factors are associated with its development. METHODS: PubMed, MEDLINE, Scopus, Web of Science and Cochran Library databases were searched with Mesh headings to locate studies linking TECSA and obstructive sleep apnea (OSA). RESULTS: Nine studies were identified that reported the prevalence of TECSA ranging from 5.0% to 20.3%. Prevalence of TECSA for studies using only full night titration was between 5.0% and 12.1% where as it was between 6.5% and 20.3% for studies using split-night polysomnogram. The mean effective continuous PAP (CPAP) setting varied between 7.5 cm and 15.2 cm of water for patients in TECSA group and between 7.4 cm and 13.6 cm of water for the group without TECSA. CONCLUSIONS: The aggregate point prevalence of TECSA is about 8% with the estimated range varying from 5% to 20% in patients with untreated OSA. The prevalence tends to be higher for split-night studies compared to full night titration studies. TECSA can occur at any CPAP setting although extremely high CPAP settings could increase the likelihood. Male gender, higher baseline apnea-hypopnea index, and central apnea index at the time of diagnostic study could be associated with the development of TECSA at a subsequent titration study.