Endogenous Hydrogen Sulfide And Cognitive Function In Patients With Obstructive Sleep Apnea-hypopnea Syndrome

Objective To explore the relation between the cognitive impairment andendogenous hydrogen sulfide (H₂S) in patients with obstructive sleepapnea-hypopnea syndrome (OSAHS).Methods Mini Mental State Examination (MMSE) was conducted to 45 patientswith OSAHS (OSAHS group) and 30 healthy adults (control group).Polysomnography was administered to OSAHS group for 7 hours at night.Levels of plasma H₂S was measured by sensitive sulphur electrode.Results The scores of MMSE (24.67±2.06, control group: 28.90±0.67;P<0.01),memory (2.24±0.57, control group: 2.93±0.26; P<0.01),attention(3.57±1.06, control group: 5.66±0.66; P<0.01) and recall (1.38±0.78, control group: 2.45±0.51; P<0.01) were significantly lower than those of the controls. The plasma H₂S level of the patients with OSAHS was (34.26±2.39)μmol/LJ significantly lower than that of the controls(41.43±2.19μmol/L, P<0.01). The H₂S level was significantly positively correlated with the scores of MMSE(r=0.7408, P<0.01), attention (r=0.3217, P<0.05),recall (r=0.3024, P<0.05) and LSaO₂ (r=0.713 , P<0.01) , negatively correlated with AHI (r=-0.926, P<0.01) and LAT (r=-0.474, P<0.01) . Conclusion OSAHS patients have cognitive disorder. Endogenous H₂S may play a role in the cognitive impairment in patients with OSAHS. Nocturnal hypoxemia may be the reason of the decrease of the plasma H₂S level in patients with OSAHS.