Objective: To explore the relationship between serum homocysteine (Hcy) level and oxidative stress in patients with obstructive sleep apnea-hypopnea syndrome (OSAHS).
Methods: Patients undergoing overnight full polysomnography (PSG) were selected from Sleep Disorders Center at First Affiliated Hospital between June 2008 and December 2013. A total of 117 OSAHS patients were recruited and divided into 3 groups of mild (n = 41), moderate (n = 40) and severe (n = 36). And they were compared with the controls (n = 33). The PSG variables were recorded and the contents of Hcy, malonaldehyde (MDA) and glutathione (GSH) detected after sleep. Serum Hcy was measured by cyclophorase. And MDA and GSH were measured by spectrophotometer.
Results: The concentrations of MDA in severe group were higher than those in the other three groups ((7.3 ± 1.0) vs (4.6 ± 0.9), (5.4 ± 1.3), (6.8 ± 0.7) µmol/L, all P < 0.05). The concentrations of GSH in mild and moderate groups were both higher than the controls ((6.5 ± 2.1), (7.5 ± 1.5) vs (4.2 ± 1.4) mg/L, all P < 0.05). However there was no significant difference between severe group ((4.6 ± 1.4) mg/L) and controls (P > 0.05). The Hcy level in mild and moderate groups were both higher than the controls ((10.3 ± 2.0), (13.3 ± 2.6) vs (8.7 ± 0.7) µmol/L, all P < 0.05). However there was no significant difference between severe group ((9.5 ± 1.8) µmol/L) and controls (P > 0.05). When severe group was removed, multielement linearity regression analysis indicated that there was a statistically significant relationship between Hcy concentration and age, MDA, GSH, apnea hypopnea index (AHI) and oxygen desaturation index (ODI) (P = 0.011, 0.005, 0.008, 0.001, 0.016 respectively).
Conclusions: The change of marker levels in oxidative stress is not entirely consistent with the antioxidant levels in OSAHS patients at different stages of disease. The change of Hcy level is proportional to GSH level, but not proportional to severity in OSAHS patients. The mechanism of serum Hcy change may be oxidative stress in OSAHS patients.