Fig. 2.

Obstructive sleep apnoea parameters. A. Presence and severity of obstructive sleep apnoea (OSA) based on the apnoea–hypopnoea index in IIH patients. B. Apnoea-hypopnoea index in patients with IIH at baseline comparing the two arms of community weight management intervention (CWI) and bariatric surgery. Level of the bars represents median and error bars interquartile range. Wilcoxon signed ranks test to assess differences between baseline and 12 months in the two groups. Mann–Whitney test to assess differences between arms at 12 months. C, D. Linear regression analysis showing the percentage change (Δ) of apnoea–hypopnoea index against percentage change (Δ) in intracranial pressure and OCT optic nerve head central thickness at 12 months after baseline in IIH patients. Spearman’s rank order used to assess correlations. *Denotes statistical significance p < 0.05, difference between apnoea–hypopnoea index of the bariatric surgery group at 12 months compared to baseline. IIH idiopathic intracranial hypertension, ICP intracranial pressure, OCT optical coherence tomography, AHI apnoea–hypopnoea index