Homocysteine level in patients with obstructive sleep apnea/hypopnea syndrome and the impact of continuous positive airway pressure treatment

BACKGROUND: Obstructive sleep apnea/hypopnea syndrome (OSAHS) is a common disorder in the general population. OBJECTIVES: The aim of this study was to investigate the homocysteine (Hcy) level in the patients with OSAHS of varying degrees and the effect of continuous positive airway pressure (CPAP) treatment on OSAHS patients. MATERIAL AND METHODS: A total of 117 OSAHS patients were recruited and divided into 3 groups (mild OSAHS, moderate OSAHS and severe OSAHS), while 33 non-OSAHS people were selected as control group. For all cases, polysomnography (PSG) variables and the concentrations of Hcy, methane dicarboxylic aldehyde (MDA) and glutathione (GSH) were recorded. Serum Hcy was measured by cyclophorase. The values of MDA and GSH were measured by a spectrophotometer. In the severe OSAHS group, a total of 30 patients received CPAP for more than 4 h every night and were re-examined 6 months later. RESULTS: The serum levels of Hcy, MDA and GSH showed a significant difference in OSAHS patients and controls. The Hcy and GSH concentrations of OSAHS patients with CPAP treatment showed no apparent change compared with the prior treatment, but the MDA level was obviously lower after CPAP treatment. In controls and the mild/moderate OSAHS groups, multi-element linear regression analysis results indicated that there was a statistically significant relationship between the Hcy concentration and various independent variables (age, MDA, GSH, and the apnea-hypopnea index - AHI). CONCLUSIONS: The change of the Hcy level was not proportional to the severity of the disease in different groups of OSAHS patients, and CPAP did not affect the Hcy levels.