Objective  To investigate the predictive value of nocturnal pulse oxygen saturation(SpO₂) in patients with obstructive sleep apnea hypopnea syndrome (OSAHS) complicating with type 2 diabetes.

  Methods  The clinical data of 153 patients with OSAHS were retrospectively analyzed, and they were divided into single OSAHS group (76 cases) and OSAHS with type 2 diabetes group (77 cases) according to whether they had type 2 diabetes or not. The demographic data, the medical history data and SpO₂ level between the two groups were compared, and the predictive efficacy of nocturnal SpO₂ for OSAHS patients with type 2diabetes was analyzed.

  Results  Compared with the single OSAHS group, the age of the OSAHS with type 2 diabetes group was older, body mass index (BMI), apnea hypopnea index (AHI) and oxygen deoxygenation index (ODI) were higher, prevalence of hyperlipidemia and proportion of family history of diabetes were higher, the mean oxygen saturation (MSpO₂) and lowest oxygen saturation (LSpO₂) levels were lower (P < 0.05). Logistic regression analysis showed that younger age(OR=0.247, 95%CI, 0.110 to 0.553, P=0.001) and lower BMI(OR=0.366, 95%CI, 0.152 to 0.881, P=0.025) were protective factors forOSAHS patients complicating with type 2 diabetes, while hyperlipidemia (OR=2.337, 95%CI, 1.068 to 5.113, P=0.034)and decreased LSpO₂(OR=3.511, 95%CI, 1.132 to 10.891, P=0.030) were risk factors for OSAHS patients with type 2 diabetes. The optimal cut-off value of LSpO₂ in predicting OSAHS patients with type 2 diabetes mellitus was 76.50% (with sensitivity of 54.5%, specificity of 75.0%).

  Conclusion  LSpO₂ is associated with the occurrence of type 2 diabetes in patients with OSAHS, and the reduced LSpO₂ level may have a certain predictive value for patients with OSAHS complicating with type 2 diabetes.