【Abstract】 Objective To study the effects of obstructive sleep apnea hypopnea syndrome ( OSAHS) on blood pressure variations, and explore the possible mechanism. Methods 84 adult patients ( mean age 50. 1 ±14. 8 years, male /female 67 /17) were recruited for polysomnography ( PSG) and ambulatory blood pressure monitoring. Four groups were identified based on apnea hyponea index ( AHI) ,ie. non-OSAHS group ( n=9) ,mild group ( n=19) , moderate group ( n=23) , and severe group ( n =33) .The blood pressure levels were compared among the four groups. Correlations between PSG indexes,variations of systolic blood pressure ( SBP) and diastolic blood pressure ( DBP) were analyzed. Results Inter-group blood pressure comparison showed significant differences in SBP and DBP( P lt;0. 05) , except forthe mild and the moderate OSAHS patients. As compared with the non-OSAHS patients, SBP for those with severe OSAHS was about 15 mm Hg higher, and DBP 10 mm Hg higher. Observation on SBP non-dipping rate indicated that, except for the mild and the moderate OSAHS patients where no significant differences were found, SBP non-dipping rate increased with the severity of OSAHS( the rates were 78. 3%, 57. 1% ,54. 5%, and 32. 6% , respectively for the four groups) , whereas DBP non-dipping rate significantly increased in the severe OSAHS patients( 54. 3% ) ( P lt;0. 05) . For the mild OSAHS patients, blood pressure was found to be correlated positively with the body mass index ( correlation coefficient for day time SBP was 0. 26, and for DBP was 0. 22) , the arousal index ( correlation coefficient for day time SBP was 0. 25, and for DBP was 0. 17) , and heart rate variation ( correlation coefficient for night time SBP was 0. 18, and for DBP was 0. 17) . For the moderate OSAHS patients, a positive correlation was also found between blood pressure and AHI ( correlation coefficient for day time SBP was 0. 31, and for DBP was 0. 22, correlation coefficient fornight time SBP was 0. 26) , and between blood pressure and the longest hypopnea time during sleep ( LH) ( correlation coefficient for night time DBP was 0. 2) . For the severe OSAHS patients, blood pressure was correlated positively with apnea index ( AI) ( correlation coefficient for day time SBP was 0. 61, and for DBP was 0. 5, correlation coefficient for night time SBP was 0. 57 and for night time DBP was 0. 48) . Conclusions OSAHS has ber impact on SBP than on DBP. DBP hypertension and SBP non-dipping are usually found in early OSAHS-affected patients. Factors affecting blood pressure differ with the severity of the OSAHS.
Objective To investigate the characteristics of blood pressure and coronary artery impairment in patients with essential hypertension (EH) combining coronary heart disease (CHD). Methods A total of 358 patients with EH combining CHD and other 144 patients with CHD were measured with ambulatory blood pressure monitoring (ABPM), and the parameters of ambulatory blood pressure were analyzed. All the patients underwent coronary angiography. The severity of coronary artery stenosis was evaluated in accordance with the number of impaired arteries. Results Compared to the patients with simplex CHD, those with EH combining CHD had much heavier artery stenosis and more diffuse lesions, with significant differences (χ2=6.03, P=0.019). The 24h systolic blood pressure (SBP), day SBP, night SBP, 24h pulse pressure (PP), day PP and night PP were higher in the patients with EH combining CHD compared to those of the patients with simplex CHD (The t values were 2.580, 2.045, 2.675, 2.037, 2.601, and 1.995, respectively, while the P values were 0.015, 0.037, 0.009, 0.041, 0.017, and 0.047, respectively). Conclusion Compared to the patients with simplex CHD, the patients with EH combining CHD suffer from much severe coronary artery impairment, so a good controlling of blood pressure is advisable to improve the coronary artery impairment for the patients with EH combining CHD.
ObjectiveTo investigate the value of morning blood pressure surge in the evaluation of atherosclerosis by the observation of the relationship between morning blood pressure surge and ambulatory arterial stiffness index. MethodsFrom May 2011 to March 2013, we followed up 300 hypertensive patients who received ambulatory blood pressure monitoring, and they were divide into elevated morning blood pressure surge group and non-elevated morning blood pressure surge group. The AASI value was recorded and compared between the two groups according to the grade of hypertension. ResultsMorning blood pressure surge was more common in patients with hypertension. Compared with patients in the non-elevated morning blood pressure surge group, ambulatory arterial stiffness index was significantly higher in patients in the elevated morning blood pressure surge group. ConclusionThere is a certain correlation between morning blood pressure surge and arterial stiffness, which is an important factor leading to a variety of target organ damage.
ObjectiveTo compare home blood pressure monitoring (HBPM) versus ambulatory blood pressure monitoring (ABPM) versus office blood pressure monitoring (OBPM) in diagnosis and management of hypertension, and to find the optimal blood pressure measurement and management.MethodsThe following were compared among three BP monitoring, such as cost-effectiveness, prognostic value of target organ damage (TOD), predictive value of the progress in chronic kidney disease (CKD) and blood pressure variety (BPV). ResultsCompared to OBPM, ABPM was the most cost-effective method in the primary diagnosis of hypertension, but HBPM was the optimal method in long-term and self-management in hypertension. In hypertensives, compared to OBPM, HBPM and ABPM, especially HBPM, had a stronger predictive value for cardiovascular events, stroke, end-stage renal dysfunction (ESRD) and all-cause mortality. In hypertensives with renal dysfunction, controlling HBPM and ABPM, especially controlling ABPM, was an effective way to slow the progress in renal dysfunction, to decrease cardiovascular events, and to decrease the need of dialysis. All BPV derived from OBPM, ABPM and HBPM had a predictive significance of cardiovascular events, and HBPM BPV performed the best.ConclusionCompared to OBPM, ABPM is the best method in primary diagnosis of hypertension and BP control in CKD patients, while HBPM is the best method in predicting and in evaluating BPV, as well as in long-term and self-management in hypertension.
Sleep apnea causes cardiac arrest, sleep rhythm disorders, nocturnal hypoxia and abnormal blood pressure fluctuations in patients, which eventually lead to nocturnal target organ damage in hypertensive patients. The incidence of obstructive sleep apnea hypopnea syndrome (OSAHS) is extremely high, which seriously affects the physical and mental health of patients. This study attempts to extract features associated with OSAHS from 24-hour ambulatory blood pressure data and identify OSAHS by machine learning models for the differential diagnosis of this disease. The study data were obtained from ambulatory blood pressure examination data of 339 patients collected in outpatient clinics of the Chinese PLA General Hospital from December 2018 to December 2019, including 115 patients with OSAHS diagnosed by polysomnography (PSG) and 224 patients with non-OSAHS. Based on the characteristics of clinical changes of blood pressure in OSAHS patients, feature extraction rules were defined and algorithms were developed to extract features, while logistic regression and lightGBM models were then used to classify and predict the disease. The results showed that the identification accuracy of the lightGBM model trained in this study was 80.0%, precision was 82.9%, recall was 72.5%, and the area under the working characteristic curve (AUC) of the subjects was 0.906. The defined ambulatory blood pressure features could be effectively used for identifying OSAHS. This study provides a new idea and method for OSAHS screening.