Circulating C3 and glucose metabolism abnormalities in patients with OSAHS

Purpose Obstructive sleep apnea hypopnea syndrome (OSAHS) is a common breathing disorder during sleep characterized by multiple disease roots, including disorders of complement and glycometabolism. And the main purpose of the present study is to make clear the effect of complement C3 on glucose metabolism abnormalities in patients with OSAHS. Methods This was a cross-sectional study. Two hundred six patients, mean age 44.58 ± 11.84 years and 26 female patients (26/206), had been suspected with OSAHS and underwent overnight polysomnography. The assessment of complement levels included complement 3 (C3), complement 4 (C4), and serum total complement (TC). The measured indicators of glucose metabolism were fasting blood glucose (FPG), fasting insulin (FINS), and 75 g oral glucose tolerance test-derived glucose. A multivariate linear regression was used to determine relevant factors with 2-h postprandial blood glucose (2hPG) and C3. Results The patients were classified according to apnea-hypopnea index (AHI) into four groups: simple snore ( n = 21), mild OSAHS ( n = 43), moderate OSAHS ( n = 35), and severe OSAHS ( n = 107). The level of C3 in the severe OSAHS was higher than other groups (simple snore: 1.16 ± 0.18 g/L VS 1.00 ± 0.18 g/L, p