The modified Baveno classification for obstructive sleep apnoea: development and evaluation based on the ESADA database

Background: The "Baveno classification" replaced the apnoea-hypopnoea index (AHI) with symptoms and comorbidities for treatment indication in obstructive sleep apnoea (OSA). This study evaluates a modified Baveno classification which adds a validated cardiovascular disease (CVD) risk score and acknowledges severe breathing disturbances.

Method: OSA patients from the European Sleep Apnoea Database (ESADA) were retrospectively allocated into CVD risk groups 1-3 based on the SCORE2 risk prediction model and European Society of Cardiology guidelines. AHI ≥30 events·h^-1 conferred strong treatment indication. When AHI was <30 events·h^-1, symptoms and CVD risk dictated allocation to the weak, intermediate or strong treatment indication group. Changes in Epworth Sleepiness Scale (ESS) score and office systolic blood pressure (SBP) at follow-up (12-24 months) under positive airway pressure (PAP) were assessed.

Results: 8625 patients were analysed (29% female; median (interquartile range) age 56 (49-64) years and body mass index 31.9 (28.4-36.3) kg·m^-2). Treatment indication was weak in 501 (6%), intermediate in 2085 (24%) and strong in 6039 (70%). There was a continuous increase in age, SBP, C-reactive protein and glycosylated haemoglobin from weak to strong (p<0.001). PAP prescription increased from 52% to 64% to 93% (weak to strong; p<0.001). The change in ESS score was -2, -4 and -5, respectively (p<0.001). Reductions of ≥3 mmHg median SBP occurred when AHI was ≥30 events·h^-1 and in symptomatic patients with CVD risk levels >1 when AHI was <30 events·h^-1.

Conclusion: This analysis provides supporting evidence for the key role of CVD risk assessment and severe breathing disturbances in the identification of OSA patients most likely to benefit from treatment.