Jens Christian Laursen1*, Randi Jepsen2 , Neda Esmailzadeh Bruun-Rasmussen2 , Marie Frimodt-Møller1 , Marit Eika Jørgensen3 , Peter Rossing1,4 and Christian Stevns Hansen1

1 Complications Research, Steno Diabetes Center Copenhagen, Herlev, Denmark,

2Center for Epidemiological Research, Nykøbing Falster Hospital, Nykøbing Falster, Denmark,

3Steno Diabetes Center Greenland, Nuuk, Greenland, 4Department of Clinical Medicine, University of Copenhagen, Copenhagen, Denmark

Aims: Low blood oxygen saturation is associated with increased mortality and persons with diabetes have sub-clinical hypoxemia. We aimed to confirm the presence of sub-clinical hypoxemia in pre-diabetes, screen-detected diabetes and known diabetes.

Methods: Pre-diabetes was defined as hemoglobin A1C (HbA1C) ≥ 42 mmol/mol and <48 mmol/mol; known diabetes as history or treatment of diabetes; screen-detected diabetes as no history or treatment of diabetes and HbA1C ≥ 48 mmol/mol. Blood oxygen saturation was measured with pulse oximetry. Urine albumin-to creatinine ratio (UACR) was measured on a single spot urine.

Results: The study included 829 adults (≥18 years) with diabetes (713 (86%) with known diabetes; 116 (14%) with screen-detected diabetes) and 12,747 without diabetes (11,981 (94%) healthy controls; 766 (6%) with pre-diabetes). Mean (95% CI) blood oxygen saturation was 96.3% (96.3% to 96.4%) in diabetes which was lower than in non-diabetes [97.3% (97.2–97.3%)] after adjustment for age, gender, and smoking (p < 0.001), but significance was lost after adjustment for BMI (p = 0.25). Sub-groups with pre-diabetes and screen-detected diabetes had lower blood oxygen saturations than healthy controls (p-values < 0.01). Lower blood oxygen saturation was associated with higher UACR.

Conclusions: Persons with pre-diabetes and screen-detected diabetes have sub-clinical hypoxemia, which is associated with albuminuria.

KEYWORDS

hypoxia, microvascular complications, albuminuria, type 2 diabetes, pre-diabetes