Objective:To analyze the changes of carotid-femoral and carotid-radial pulse wave velocity in patients with obstructive sleep apnea hypopnea syndrome (OSAHS)associated with hypertension,and effect factors on these changes. Methods:One hundred and sixty research objects were classified into four groups according to the hypertension history and polysomnography(PSG):control group (40 patients),hypertension group (40 patients),OSAHS group (40 patients),and OSAHS with hypertension group (40 patients). Automatic pulse wave velocity measuring system was applied to examine carotid-femoral pulse wave velocity(c-fPWV) and carotid-radial pulse wave velocity(c-rPWV) as the parameters reflecting central elastic large arterial and peripheral muscular medium-sized arterial elasticity respectively. Results:Compared to control group,hypertension,OSAHS,and OSAHS with hypertension groups had significantly higher c-fPWV(F = 23.056,P < 0.05),and OSAHS with hypertension group had significantly higher c-fPWV than hypertension group[(10.72 ± 1.06)m/s]vs[(10.09 ± 1.05)m/s,P < 0.01]. Compared to control group,hypertension,OSAHS with hypertension group had significantly higher c-rPWV(P < 0.01). C-fPWV correlated significantly with c-rPWV (all P < 0.01) by both Pearson and partial correlation analysis adjusted by age,body mass index,waist-hip ratio,systolic blood pressure,diastolic blood pressure and heart rate. Multiple stepwise regression analysis showed that the age,systolic blood pressure and heart rate were positively while female gender was negatively correlated with c-fPWV (R2 = 0.537,P = 0.000). C-rPWV was positively correlated with diastolic blood pressure(R2 = 0.052,P= 0.041).Conclusion:Our study showed that arterial stiffness was increased in OSAHS patients,and with OSAHS exacerbations,c-fPWV value increased. Arterial stiffness was more severe in the patients with OSAHS and hypertension. The change of c-fPWV of patients with OSAHS was related to age,female gender,systolic blood pressure and heart rate. C-rPWV was associated with diastolic pressure. The PWV would be an applicable functional index in early diagnosis of vascular pathological changes and in medical evaluation . Examining the change of large arterial elasticity has important clinical value in OSAHS patients.