Abstract
Objective To investigate the function change index of vascular endothelial cells (EC), plasma levelsof nitricoxide (NO) and endothelin (ET) in elderly Chinese patients with obstructive sleepapnea hypopnea syndrome(OSAHS) and its associat ion with coronary heart disease (CHD). Methods 31 elderly simple snorers with neitherOSAHSnor CHD were randomly selected as control group. 45 elderly patients with moderate or severe degree of OSAHS wererecruited as OSAHS group, which were further divided into two subgroups, CHD subgroup (16 pat ients) and non CHDsubgroup (29 pa tients). The changes of plasma concentrations of NO and ET were tested and compared from group togroup. Results Compared with control group, in OSAHS group there was a significant lower NO level (27.69±9. 17mmol/Lvs 61.90± 13.47, P<0. 01), higher ET level (58.08±14.21pg/ml vs 34. 77±8.23pg/ml, P<0. 01), and lower rate of NO/ET(0. 47±0. 18 vs 1. 72±0. 97mmol/L, P<0. 01). The incidence of CHD in OSAS group was 35.6%. Comparison between controlgroup and non-CHD OSAHS subgroup showed that the decreased NO level (35.53±9.39), increased ET level(47.78±11.13pg/ml) and declined NO/ET (0.75±0.13) in non CHD subgroup were statistically significant (P<0.05).Such a difference was more significant between conrol group and CHD OSAS subgroup (P<0. 01). Comparison between thetwo subgroups in OSAHS group indicated that there was a significantly lower NO level, higher ET level and more declinedNO/ET in OSAHS with CHD subgroup than in OSAHS without CHD subgroup (all P<0.05). Conclusion Vascular endothelialfunction was significantly impaired in elderly Chinese patients with OSAHS, especially in those with both OSAHSand CHD. Dysfunction of vascular EC may be one of the causes of complicated CHD in OSAHS patients.