ABSTRACT
Objective To explore the correlation between obstructive sleep apnea hypoventilation syndrome (OSAHS)and glucose metabolism disorders in patients without diabetes mellitus.Methods A total of 88 patients with OSAHS but without diabetes mellitus from 2009 to 2011 in our hospital were selected and the pulse oximeter were used to measure the oxygen saturation.Patients were divided into 2 groups:the mild OSAHS group (n=46) and the severe OSAHS group (n=42).The age-and body mass index (BMI) matched control patients without OSAHS (control group,n =48) were randomly selected.The medical history,age,body height and BMI were recorded.The levels of fasting blood glucose,glycated hemoglobin (HbA1c),cholesterol,triglyceride and low density lipoprotein cholesterol were determined.Results There were significant differences in the numbers of respiratory disorders,respiratory disturbance index,average length of apnea,the longest apnea time,low-oxygen frequency,oxygen index,the time of oxygen saturation (SaO2) below 90％,minimum SaO2 and mean SaO2 between the OSAHS group and the control group (F=2.71,2.89,1.94,2.30,2.93,2.27,3.66,3.06,1.82,respectively,all P＜0.05).There were differences in the levels of fasting blood glucose,postprandial blood glucose,HbA1c,cholesterol,triglycerideand low density lipoprotein cholesterol between the three groups(F=1.81,1.85,2.16,1.77,2.24,2.19,respectively,all P＜0.05).Conclusions The severe degree of OSAHS has the correlation with the levels of glycated hemoglobin and blood glucose,which can provide a basis to observe the duration of diabetes mellitus and to predict the risk of cardiovascular diseases.
ABSTRACT
Objective To investigate the expression of endothelin-1 (ET-1 ), nitrogen monoxidium (NO), vascular endothelial growth factor (VEGF) and brain tissue VEGF induced by chronic intermittent hypoxia (CIH) in aged rats. Methods The CIH model of aged rat was established by using intermittent hypoxia. The levels of ET-1, NO and VEGF in the plasma were detected at 3, 6 and 9 weeks after experiment in each group. The expression of VEGF in brain tissues and the pathological changes of the vessels of the cerebra and the ratio between the thickness of vessel wall and external diameter (WT%) were observed. Results In CIH group, the ET-1 and VEGF levels increased, however NO level decreased. The levels of ET-1 and VEGF were higher at 3 weeks in CIH group than in UC group (t=2.47 and 2.38, both P<0.05), however NO level was lower in CIH group than in UC group (t=2.39, P<0.05). VEGF levels increased significantly at 9 weeks in CIH as compared with UC group [(171.1±13.5) pg/ml vs. (109.8±8.6) pg/ml, t = 3.46, P< 0.01]. The levels of VEGF in CIH group increased remarkably at 9 weeks as compared with 3 weeks [(129.3±12.3) pg/ml, t=2.38, P<0.053. VEGF levels in CIH group showed positive correlation with the time of intermittent hypoxia. The changes of cerebral vessels in UC group were not found, while the aged rats in CIH group showed cerebral neuron cells swelling and blood vessel hyperplasia. The WT% of cerebral small artery was more apparent in CIH group than in UC group at 3 weeks (t=2.34,P<0.05). The expression of VEGF in cerebra was higher in CIH group than in UC group in the three stages (r=2.37, P<0.05). There was an aggravated tendency in the change of the expression of brain tissue VEGF and WT% over time. The change was more apparent at 9 weeks than at 3 weeks (t=2.32 and 2.35, both P<0.05). Conclusions CIH can induce an increase in the expression of ET-1 and VEGF, a decrease in the expression of NO in aged rats. The over expression of VEGF and the disbalance of ET-1 and NO levels can cause brain cellular swelling, arteriola vessel wall thickening,lumens stenosis.