Nocturnal oxygen saturation parameters as predictive factors for DM2 among OSA patients
Agata Gabryelska, Jędrzej Chrzanowski, Marcin Sochal, Piotr Kaczmarski, Piotr Białasiewicz
Abstract
<b>Background and aims:</b> Obstructive sleep apnea is a recognized independent risk factor for metabolic disorders, type 2 diabetes mellites (DM2) in particular. Therefore, the study aimed to assess the influence of nocturnal oxygen saturation parameters on the onset of DM2 among OSA patients. <b>Methods:</b> The study consisted of 549 participants, who underwent polysomnography (PSG) examination. Based onapnea hypopnea index (AHI) 465patients were diagnosed with OSA. One hounded and seven individuals had comorbid type 2 diabetes mellites (DM2). Cox regression models were used to assess theeffect ofoxygen saturation parameterson theonset of DM2.Classification and regression trees (CART) analysis wasused to assessthe onset of the DM2 in the study group in context of oxygen saturation variables. Funded by the Polish Ministry of Science and Higher Education grant no. 0067/DIA/2018/47. <b>Results:</b> One-way Cox regression showed higher risk of earlier DM2 for increased values of BMI (p&lt;0.001, 95%CI 1.083-1.153, HR=1.117), AHI (p=0.003, 95%CI 1.004-1.017,HR=1.011), decreased basal O<sub>2</sub> (p=0.006, 95%CI 0.886 - 0.9809, HR=0.933) and O<sub>2</sub> nadir (p=0.009, 95%CI 0.972-0.996, HR=0.984) value, while lowered mean O<sub>2</sub> desaturation has not shown statistical significance. In the CART analysis following cut-off points 92.2%, 81.7%, 87.1% were determined for basal O<sub>2</sub>, O<sub>2</sub> nadir and mean O<sub>2</sub> desaturation respectively with first 2 parameters being statistically significant. <b>Conclusions:</b> Higher SpO<sub>2</sub> nadir and basal SpO<sub>2</sub> are associated with the later onset of DM2 in OSA patients. Basal O<sub>2</sub> is independent from AHI, BMI and age is a predictor of DM2 among OSA patients.