ABSTRACT
Objectives:To investigate the common risk factors for excess daytime sleepiness (EDS) and hypertension in obstructive sleep apnea-hypopnea syndrome(OSAHS) patients.Methods:Between January 2020 and February 2021, a total of 103 OSAHS patients diagnosed in the Department of Sleep Medicine Center, the Affiliated Huaian No.1 People′s Hospital of Nanjing Medical University were enrolled as the study population. During polysomnography (PSG) monitoring, noninvasive continuous blood pressure (BP) and heart rate variability (HRV) were monitored simultaneously. Low/high frequency components (LF/HF) were used to reflect sympathetic-vagal balance in frequency domain analysis. According to Epworth Sleepiness Scale (ESS) and BP levels, patients were divided into four groups: simple OSAHS group (ESS<10 scores and BP<140/90 mmHg, n=30)(1 mmHg=0.133 kPa), OSAHS+hypertension group (ESS<10 scores and BP≥140/90 mmHg, n=23), OSAHS+EDS group (ESS≥10 scores and BP<140/90 mmHg, n=26) and OSAHS+hypertension+EDS group (ESS≥10scores and BP≥140/90 mmHg, n=24). The clinical and PSG parameters were analyzed and compared among the four groups. Regression analyses were used to explore the common causative factors for EDS and hypertension. Results:The LF/HF in OSAHS+hypertension+EDS group was significantly higher than the other three groups [3.2% (2.6%, 4.2%) vs 1.4% (1.2%, 1.6%), 2.2% (1.8%, 2.9%), 2.5% (1.6%, 3.1%), all P<0.05]. No difference was observed between OSAHS+hypertension group and OSAHS+EDS group ( P=0.779), but both higher than simple OSAHS group. The linear regression equation showed that LF/HF was most correlated with the percentage of sleep time with oxygen saturation<90% (T90) as compared to the other parameters of sleep disordered breathing (β=0.201, P=0.006). In addition, Pearson correlation analysis showed that LF/HF was significantly correlated with ESS scores and asleep BP levels ( r=0.536, r=0.456, all P<0.05). The logical regression equation showed that LF/HF was a causative risk factor for both EDS and hypertension in OSAHS (β=0.164, 95% CI: 1.018-1.364, P=0.028). Conclusion:The sympathetic-vagal imbalance is a common risk factor for EDS and hypertension in OSAHS patients