ABSTRACT
Objective To retrospectively analyze the cardiovascular outcomes of the elderly patients with obstructive sleep apnea syndrome (OSAS) and the influence factors. Methods According to polysomnography examination, 79 OSAS patients and 60 patients without OSAS were selected and divided into 3 groups: elder OSAS group [39 patients older than 65 years, respiratory apnea index (AHI)≥5], non-elder OSAS group (40 patients less than 65 years old, AHI≥5) and elder control group (60 patients older than 65 years, AHK5). All patients were followed up by telephone and clinic consulting. The median follow-up duration was 25 months. All patients received the following studies: (1)Flow-mediated vasodilation (FMD), which was assessed by high-resolution ultrasound technique. (2)The sleep-related breathing events and serum biochemical indexes. (3)The death due to cardiovascular disease (CVD), angina, myocardial infarction and stroke. Results (1) FMD was significantly lower in elder OSAS group than in elder control group (P<0. 01). (2)In elder OSAS group versus elder control group, BMI was significantly higher (P<0. 01), while both lowest pulse oxygen saturation (LSpO_2 ) and mean series pulse oximeter ( MeanSpO_2 ) were significantly lower (P< 0.01 and P<0. 05, respectively). Multiple logistic regression analysis showed that impaired fasting plasma glucose was the primary injury factor for FMD (OR=1. 83, 95% CI:1. 11～3.03), and LSpO_2 was the secondary injury factor (OR = 0.92, 95% CI: 0. 85～1. 00). (3) The incidence of cardiovascular events in the 3 groups: the incidence of cardiovascular events was significantly higher in elder OSAS group than in the other 2 groups (χ~2= 7. 339, P<0. 05). Multiple logistic regression analysis showed that FMD (OR=1. 33, 95% CI:1. 06～1. 66)and hs-CRP (OR = 0.51, 95% CI: 0. 34～0.76) were closely related with prognosis. Conclusions Compared with non-elder OSAS group and elder control group, vascular endothelial function impairment is more serious and the incidence of cardiovascular events is higher in elder OSAS group. So OSAS may influence the prognosis of the patients by injuring the vascular endothelial function.