Changes in Plasma Angiotensin II and Circadian Rhythm of Blood Pressure in Hypertensive Patients with Sleep Apnea Syndrome Before and After Treatment

Objective To explore the changes in plasma angiotensin II （Ang Ⅱ） and circadian rhythm of blood pressure among hypertensive patients with sleep apnea syndrome （SAS） before and after continuous positive airway pressure （CPAP） or surgical treatment. Methods A total of 180 essential hypertension patients were enrolled in our study. The determination of plasma Ang Ⅱ concentration, ambulatory blood pressure （ABP）, and polysomnography （PSG） monitoring were performed before and 3 months after CPAP or surgical treatment. Results Patients were classified into three groups by their apnea-hypopnea index （AHI）： essential hypertension group （EH group, n=72; AHI〈5）, essential hypertension with mild SAS group （EH＋mild SAS group, n=60, 5≤AHI〈20）, and essential hypertension with moderate and severe SAS group （EH＋moderate-severe SAS group, n=48, AHI_〉20）. The concentrations of plasma AngⅡ in the above three groups were 13.42±3.27, 16.17±3.82, and 18.73±4.05 ng/mL respectively before treatment, and AngⅡ concentration in EH patients combined with SAS was significantly higher than that in EH group （all P〈0.05）. After treatment the values in the latter two groups significantly decreased to 14.67±2.56 and 15.03±3.41 ng/mL respectively （P〈0.05）. The incidence of non-dipper blood pressure curve in EH patients was 31.9%, and those in hypertensive patients with mild SAS and moderate-severe SAS were 51.7% and 58.3%, respectively before treatment. The incidence of non-dipper blood pressure curve in the EH patients with mild SAS was significantly higher than that of patients with EH alone （P〈0.05）. After CPAP treatment or surgery, the incidence of non-dipper blood pressure curve in the two SAS groups was significantly decreased to 38.3% and 39.6%, respectively （P〈0.05）. Conclusions Ang Ⅱ might play a role in blood pressure variability in patients with obstructive SAS. CPAP or surgical treatment can improve blood pressure disorder and decrease plasma Ang Ⅱ level in patients with obstructive SAS.

The Relationship between Abnormal Circadian Blood Pressure Rhythm and Risk of Readmission in Patients with Heart Failure with Preserved Ejection Fraction

Objective:Abnormal circadian blood pressure rhythm has been revealed to be associated with hypertensive target organ damage and cardiovascular events,but its association with readmission risk in patients with heart failure with preserved ejection fraction(HFpEF)remains unknown.We conducted a retrospective study to explore the relationship between circadian blood pressure rhythm and readmission risk in HFpEF patients.Methods:We retrospectively collected baseline and follow-up data on HFpEF patients who underwent ambulatory blood pressure monitoring(ABPM)from May 2015 to October 2019.Patient circadian blood pressure rhythms defi ned by ABPM were grouped as dipper,nondipper,or riser patterns.Univariate and multivariate linear regression analyses were performed to assess the association between circadian blood pressure rhythm and readmission risk.Results:A total of 122 patients were enrolled in this study.The mean age and ejection fraction were 69.87 years and 61.44%,respectively,with mean the N-terminal pro-B-type natriuretic peptide(NT-proBNP)level being 1048.15 pg/mL.There were signifi cant differences in the 24-hour systolic blood pressure(SBP),sleep SBP,and sleep diastolic blood pressure(DBP)among the three groups,where the 24-hour SBP,sleep SBP,and sleep DBP in the riser pattern group were markedly higher than in the dipper pattern group.Notably,serum NT-proBNP levels,the proportion of patients readmitted for heart failure and the mean number of admissions differed markedly among three groups.Instructively,multivariate linear regression analysis showed that the riser pattern was a signifi cant and independent risk factor for increased serum NT-proBNP level(β=929.16,95%confi dence interval 178.79–1679.53,P=0.016).In multivariate logistic regression analysis,the riser pattern was demonstrated to be a signifi cant risk factor for readmission(odds ratio 11.23,95%confi dence interval 2.01–62.67,P=0.006)in HFpEF patients.Conclusion:The riser blood pressure pattern is a potential risk factor for elevated serum NT-proBNP level and readmission in HFpEF patients.

Effects of plasma ghrelin, obestatin, and ghrelin/obestatin ratio on blood pressure circadian rhythms in patients with obstructive sleep apnea syndrome

Background Obstructive sleep apnea syndrome （OSAS） is strongly associated with obesity and with cardiovascular disease.Ghrelin and obestatin are two peptides from the same source but have opposite roles.Both of them can affect feeding and regulate vascular tune.The aim of this study was to investigate the relationship between plasma ghrelin,obestatin,the ratio of ghrelin and obestatin （G/O） and sleep parameters and blood pressure circadian rhythms in patients with OSAS.Methods This study enrolled 95 newly diagnosed over-weight OSAS patients （OSAS group）,30 body mass index （BMI）-match non-OSAS adults （over-weight group） and 30 non-OSAS normal weight adults （control group）.Polysomnography （PSG） was performed in the OSAS group and over-weight group.Blood pressure of all subjects was monitored by means of 24-hour ambulatory blood pressure monitoring.The concentration of plasma ghrelin and obestatin was detected by enzyme-linked immunosorbent assay （ELISA）.Results Plasma ghrelin levels in the OSAS group and over-weight group were significantly lower than that of the control group （P ＜0.05）.Plasma obestatin levels were lower in the over-weight group and OSAS group,but there was no significant difference among the three groups.The blood pressure in OSAS patients was higher,and there was a significant difference in all blood pressure parameters compared to the control group,and in the daytime average diastolic blood pressure （DBP）,nocturnal average systolic blood pressure （SBP） and DBP,DBP variability values as compared to over-weight subjects.Furthermore,there were significantly more non-dipper patterns of blood pressure （including hypertension and normotension） in the OSAS group than in the other two groups （P ＜0.01）.Correlation analysis showed that ghrelin levels had a significant correlation with BMI and nocturnal average DBP but not with PSG parameters.In contrast,the G/O ratio had a negative correlation with apnea-hypopnea index （AHI） （P ＜0.05）,as well as a strong positive correlation with the blood pressure variability values （P ＜0.01）.In multivariate analyses,AHI （P ＜0.05） and G/O （P ＜0.05）were independently related to SBP variability changes,while AHI （P ＜0.05）,G/O （P ＜0.01） and BMI （P ＜0.05） were independently related to DBP variability changes.Conclusions Our data show plasma ghrelin and obestatin levels were related to obesity in OSAS.Sleep apnea in OSAS patients could have led to an imbalance in G/O in the basis of obesity.Moreover,the imbalance may promote nighttime blood pressure elevation and affect blood pressure circadian disorder.

Effect of Chinese Herbal Medicine for Calming Gan(肝) and Suppressing Hyperactive Yang on Arterial Elasticity Function and Circadian Rhythm of Blood Pressure in Patients with Essential Hypertension

Objective：To observe the effect of Chinese herbal medicine for calming Gan（肝） and suppressing hyperactive yang（平肝潜阳,CGSHY） on arterial elasticity function and the circadian rhythm of blood pressure in patients with essential hypertension（EH）.Methods：Adopting a parallel,randomized design,sixty-four patients with EH of stagesⅠandⅡwere randomly divided into two groups according to a random number table,with 32 in each group.The patients in the treatment group were treated with CGSHY and those in the control group were treated with Enalapril.All patients were given 24-h ambulatory blood pressure monitoring（ABPM） before and after a 12-week treatment.Trough/peak（T/P） ratios of systolic and diastolic blood pressure（SBP DBP） of each group were calculated.The circadian rhythm of their blood pressure was observed at the same time. The changes in elasticity of the carotid artery in the patients,including stiffness parameter（β）,pressure-strain elastic modulus（Ep）,arterial compliance（AC）,augmentation index（Al）,and pulse wave velocity（PVWβ） were determined by the echo-tracking technique before and after a 12-week treatment.In the meantime,their levels of nitric oxide（NO） and endothelin-1（ET-1） were measured respectively.Results：After treatment,all parameters in the 24-h ABPM and the elasticity of the carotid artery（β,Ep,AC and PVWβ） were markedly improved,the level of NO was increased,and ET-1 was decreased in both groups as compared with values before treatment （P0.05 or P0.01）.Further,the improvements in the ratio of T/P of SBP DBP and in the level of NO and ET-1 in the treatment group were more significant than those in the control group（P0.05）.There were no significant differences in all parameters in the ABPM monitoring and the elasticity of the carotid artery,the recovery of blood pressure circadian rhythm,and the therapeutic effect of antihypertension in EH patients between the two groups （P0.05）.Conclusions：Chinese herbal medicine for CGSHY may lower the blood pressure smoothly and recover the circadian rhythm of blood pressure in EH patients.They may also improve the carotid elasticity of EH patients similar to that of Enalapril.The mechanism of action of Chinese herbs on EH might be related to the regulation of vascular endothelium function.