Effect of obesity and glycated hemoglobin on oxygen saturation in ambulatory type 2 diabetic individuals: A pilot study

AimsTissue hypoxia is an important contributor to diabetic complications. Glycation of hemoglobin (Hb) and obesity are major determinant of oxygen saturation (SpO2) in blood. Hence, the present study was planned to evaluate the effect of obesity on SpO2 in a wide range of glycated hemoglobin (HbA1c) levels in ambulatory type 2 diabetic patients.Material and methodsA cohort of 60 subjects irrespective of diabetic status were recruited and clustered in group I (HbA1c <6.5) and group II (HbA1c ≥6.5) depending on HbA1c. Anthropometry and routine biochemical parameters were measured. HbA1c (%) were estimated by high performance liquid chromatography (HPLC) respectively. SpO2 (%) levels were measured by pulse oximetry. Pearson correlation, bivariate regression and student ‘t’ test were used for statistical analysis.ResultsBlood concentration of HbA1c was <6.5 in 29 participants and ≥6.5 in 31 participants. Plasma fasting and post prandial glucose, HbA1c as well as Hb levels were significantly (p < 0.50) higher in diabetics as compared to non diabetics. Waist circumference (WC) (r = −400; p = 0.026) and body mass index (BMI) (r = −381; p = 0.034) showed a significant negative correlation with SpO2 in diabetic patients. On adjusting HbA1c in group II, SpO2 was found to independently and inversely associated with WC (p = 0.042) and BMI (p = 0.049).ConclusionsObesity was found to be a strong independent contributor to reduction in oxygen carrying capacity in ambulatory type 2 diabetic subjects. However there is no effect of glycated Hb on SpO2 in the same population.