The Impact of National Health Insurance Expansion on Suspected Obstructive Sleep Apnea: A Nine-Year Single-Center Study.

BACKGROUND: Despite significant morbidity and mortality, obstructive sleep apnea (OSA) remains underdiagnosed. In 2018, the South Korean National Health Insurance (NHI) expanded its coverage for polysomnography (PSG) to enhance diagnostic access for suspected OSA. This study evaluated the influence of expanded NHI coverage on PSG utilization, patient demographics, and OSA diagnosis rates in a single tertiary center. METHODS: A retrospective analysis was conducted on 1,821 adult patients who underwent in-laboratory PSG between 2015 and 2023. Demographic and clinical data, including comorbidities and PSG parameters, were collected before (pre-NHI, n = 477) and after (post-NHI, n = 1,344) coverage implementation. Patient characteristics, OSA diagnosis rates, and PSG parameters were compared between the two periods. RESULTS: Post-NHI, annual PSG utilization increased by 1.8-fold compared to the pre-NHI period (2015-mid-2018), with OSA diagnosis rates rising by 9.3%, reaching 84.8%, including a 7.7% increase in severe OSA cases. The mean patient age increased by 4.3 years, with a significant increase in patients aged ≥ 60 years (33.1%) and females (22.1%). Despite a stable body mass index, OSA severity metrics and comorbidities were higher post-NHI. Referral sources expanded beyond otorhinolaryngology and comprised 31.5% of the total requests post-NHI. CONCLUSION: Expanded NHI coverage positively affected OSA detection and patient management, providing valuable insights into the potential for policy-driven improvements in the management of sleep disorders. The expanded PSG coverage effectively improved OSA detection in the underserved and high-risk populations.