OBJECTIVE: To evaluate the changes of cardiac structure and function and their risk factors in elderly patients with obstructive sleep apnea syndrome (OSA) without cardiovascular complications. METHODS: Eighty-two elderly OSA patients without cardiovascular disease admitted between January, 2015 and October, 2016 were enrolled in this study. According to their apnea-hypopnea index (AHI, calculated as the average number of episodes of apnoea and hypopnoea per hour of sleep), the patients were divided into mild OSA group (AHI < 15) and moderate to severe OSA group (AHI ≥ 15). The demographic data and the general clinical data were recorded and fasting blood samples were collected from the patients on the next morning following polysomnographic monitoring for blood cell analysis and biochemical examination. Echocardiography was performed within one week after overnight polysomnography, and the cardiac structure, cardiac function and biochemical indexes were compared between the two groups. RESULTS: Compared with those with mild OSA group, the patients with moderate to severe OSA had significantly higher hematocrit (0.22±0.08 CONCLUSIONS Cardiac diastolic function impairment may occur in elderly patients with moderate or severe OSA who do not have hypertension or other cardiovascular diseases, and the severity of the impairment is positively correlated with AHI.
Aged ; Cardiovascular Diseases/etiology* ; Humans ; Risk Factors ; Severity of Illness Index ; Sleep Apnea, Obstructive/complications* ; Stroke Volume ; Ventricular Dysfunction, Left ; Ventricular Function, Left

OBJECTIVE: To investigate the correlation between the severity of obstructive sleep apnea syndrome (OSAS) and red cell distribution width (RDW) in elderly patients. METHODS: A cross-sectional study was conducted among 311 elderly patients diagnosed with OSAS in the snoring clinic between January, 2015 and October, 2016 and 120 healthy controls without OSAS from physical examination populations in the General Hospital of PLA. The subjects were divided into control group with apnea-hypopnea index (AHI) <5 (=120), mild OSAS group (AHI of 5.0-14.9; =90), moderate OSAS group (AHI of 15.0-29.9; =113) and severe OSAS group (AHI ≥ 30; =108). The clinical characteristics and the results of polysomnography, routine blood tests and biochemical tests of the subjects were collected. Multiple linear regression analysis was used to examine the correlation between OSAS severity and RDW. RESULTS: The levels of RDW and triglyceride were significantly higher in severe OSAS group than in the other groups ( < 0.01). The levels of fasting blood glucose and body mass index were significantly higher in severe and moderate OSAS groups than in mild OSAS group and control group ( < 0.05 or < 0.01). Multiple linear regression analysis showed that AHI was positively correlated with body mass index (β=0.111, =0.032) and RDW (β=0.106, =0.029). The area under ROC curve of RDW for predicting the severity of OSAS was 0.687 (=0.0001). CONCLUSIONS The RDW increases as OSAS worsens and may serve as a potential marker for evaluating the severity of OSAS.
Aged ; Cross-Sectional Studies ; Erythrocyte Indices ; Humans ; Polysomnography ; Severity of Illness Index ; Sleep Apnea, Obstructive