Metabolomics Analysis on Obesity-Related Obstructive Sleep Apnea After Weight Loss Management: A Preliminary Study

Figures

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  Figure 1. Flow diagram of the recruitment process. T2DM, type 2 diabetes; OSA, obstructive sleep apnea; RYGB, Roux-en-Y gastric bypass surgery; PSG, polysomnography.

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  Figure 2. (A). PLSDA scores between OSA non-remission and remission groups at baseline; (B). OPLS-DA scores between OSA non-remission and remission groups at baseline; (C). Volcano plot of differential metabolites generated by univariate analysis between OSA non-remission and remission groups at baseline. UP indicates that the level of the metabolite (hippurate) was higher in the OSA non-remission group than the OSA remission group before RYGB surgery. NONE indicates 51 metabolites with no significant difference between the OSA remission and non-remission groups before RYGB surgery; (D). Boxplot of hippurate generated by univariate analysis compared between OSA non-remission and remission groups. (B) indicates the OSA remission group and (C) indicates the OSA non-remission group. PLS-DA, partial least squares-discriminant analysis; OPLS-DA, orthogonal partial least squares-discriminant analysis; OSA, obstructive sleep apnea; RYGB, Roux-en-Y gastric bypass surgery.

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  Figure 3. (A). PLS-DA scores reflecting metabolic changes in the OSA remission group before and after RYGB surgery; (B). OPLS-DA scores reflecting metabolic changes in the OSA remission group before and after RYGB surgery. (C) Volcano plot of differential metabolites generated by the univariate analysis before and after RYGB surgery; UP indicates the three metabolites that increased after RYGB surgery in the OSA remission group. DOWN indicates the three metabolites that decreased after RYGB surgery in the OSA remission group. NONE indicates the 46 metabolites with no significant expression differences after RYGB surgery in the OSA remission group; (D) Boxplot of six differential metabolites with statistical significance generated by univariate analysis. B indicates the preoperative OSA remission group and E indicates the postoperative OSA remission group. PLS-DA, partial least squares-discriminant analysis; OSA, obstructive sleep apnea; OPLS-DA, orthogonal partial least squares-discriminant analysis; RYGB, Roux-en-Y gastric bypass surgery.

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  Figure 4. (A). ROC curve and AUC values of hippurate on predicting OSA remission after RYGB surgery; (B) ROC curve and AUC values of combined preoperative indices (age, AHI, and fasting C-peptide level) on predicting OSA remission after RYGB surgery; (C) ROC curve and AUC values of combined preoperative indices (age, AHI, and fasting C-peptide and hippurate levels) on predicting OSA remission after RYGB surgery. Abbreviations: ROC, receiver operating characteristic; AUC, area under the curve; AHI, apnea–hypopnea index.