A Study on the Diurnal Variation of Ventricular Repolarization Parameters in Patients with Obstructive Sleep Apnea
Obstructive sleep apnea hypopnea syndrome (OSAHS) is a common sleep breathing disorder. More and more studies have shown that OSAHS has a significant correlation with cardiovascular disease. It is an independent risk factor for arrhythmia, hypertension, coronary heart disease and other cardiovascular diseases, but the specific mechanism is still not completely clear. Relevant evidence indicates that ventricular repolarization parameters such as Tp-e interval, QT interval and Tp-e/QT ratio may be related to arrhythmia and even sudden cardiac death. However, up to now, there are relatively few studies on OSAHS-related arrhythmias and changes in cardiac electrical parameters.
To study the diurnal variation of ventricular repolarization parameters in patients with obstructive sleep apnea.
A total of 159 OSAHS patients who met the inclusion criteria and received polysomnography monitoring in the First Affiliated Hospital of Zhengzhou University from June 2020 to July 2021 were selected as the observation group, further divided into mild-moderate OSAHS group (n=78) and severe OSAHS group (n=81) according to the severity. Fifty-one healthy people without disease were selected as the control group. Daytime and nocturnal Tp-e interval, QT interval, Tp-e/QT ratio were measured and calculated for all participants.
There were significant differences in daytime Tp-e interval, nocturnal Tp-e interval, daytime Tp-e/QT ratio, nocturnal Tp-e/QT ratio among the control group、the mild-moderate OSAHS group and the severe OSAHS group (P<0.001) . In addition, the daytime Tp-e interval, nocturnal Tp-e interval, daytime Tp-e/QT ratio and nocturnal Tp-e/QT ratio have a gradually increasing trend among the three groups (P<0.05) . There were no significant differences in daytime QT interval and nocturnal QT interval among the three groups (P>0.05) .Tp-e interval, QT interval, Tp-e/QT ratiosin the observation group were statistically different between daytime resting state and nocturnal obstructive state (P<0.05) ; The Tp-e interval, QT interval, and Tp-e/QT ratio in nocturnal obstructive state were significantly longer than those in daytime resting state (P<0.05) .The nocturnal Tp-e interval (rs=0.221, P=0.005) and nocturnal Tp-e /QT (rs=0.298, P<0.001) of OSAHS patients were positively correlated with AHI.
Ventricular repolarization parameters in OSAHS patients during nocturnal obstructive apnea are longer than those in daytime resting state, and the diurnal variation is significant, which provides a new idea for the future study of OSAHS with arrhythmia.
Characteristics of Attention Deficit and Hyperactivity Disorder in Children with Sleep-disordered Breathing
Children with sleep-disordered breathing (SDB) are more prone to attention deficit, and hyperactivity disorder, which seriously impairs their learning ability and long-term intellectual development. However, there is a lack of comprehensive analysis of attention deficit, and hyperactivity disorder in SDB children.
To investigate the characteristics of attention deficit, and hyperactivity disorder in children with SDB, so as to provide a basis for making clinical decisions for such patients.
Children aged 4-10 years with snoring or mouth breathing, who were admitted to the Sleep Center, Beijing Children's Hospital, Capital Medical University from May 2020 to June 2021 were selected. Physiologic parameters during sleep were measured by polysomnography. Attention deficit and hyperactivity disorder symptoms were assessed by parent-rated attention deficit and hyperactivity disorder Symptoms Scale (PASS) . The severity of obstructive sleep apnea (OSA) was classified by obstructive apnea-hypopnea index (OAHI) : OAHI≤1 event/hour, 1<OAHI≤5 events/hour and OAHI>5 events/hour were defined as primary snoring, mild OSA, and moderate to severe OSA, respectively. Polysomnographic parameters〔total sleep time, sleep efficiency, non-rapid eye movement (NREM) sleep stage 1 (N1%) , stage 2 (N2%) , and stage 3 (N3%) and REM sleep percentage of total sleep time (R%) , OAHI, arousal index (ArI) , oxygen desaturation index (ODI) , average oxygen saturation (SpO2) and SpO2 nadir〕 were compared by the severity of OSA. The prevalence of attention deficit, hyperactivity disorder, and attention deficit and hyperactivity disorder diagnosed by the PASS were compared by the severity of OSA, sex and age.
Seventy-six cases of primary snoring, 86 cases of mild OSA and 77 cases of moderate to severe OSA were included. Moderate to severe OSA children had greater N1%, OAHI, ArI, and ODI, and lower average SpO2 and SpO2 nadir than other two groups (P<0.05) . The R% of moderate to severe OSA group was lower than that of primary snoring group (P< 0.05) . OAHI, ArI and ODI were higher and SpO2 nadir was lower in children with mild OSA than those with primary snoring (P<0.05) . The prevalence of attention deficit, and attention deficit and hyperactivity disorder diagnosed by the PASS in moderate to severe OSA group was statistically higher than that in primary snoring group (P '<0.016 7) . Male children had higher prevalence of attention deficit, hyperactivity disorder, and attention deficit and hyperactivity disorder diagnosed by the PASS than female children (P<0.05) . Compared with preschoolers, school-age children have higher prevalence of attention deficit and attention deficit and hyperactivity disorder diagnosed by the PASS (P<0.05) .
The prevalence of attention deficit and hyperactivity disorder in children with SDB was higher than that in the general population. Male children had higher prevalence of attention deficit and hyperactivity disorder than female children. And the prevalence of attention deficit in school-age children was higher than that in preschoolers.
The Value of Abdominal Visceral Adipose Tissue Area and Homeostasis Model Assessment of Insulin Resistance in Predicting Essential Hypertension Complicated with Obstructive Sleep Apnea Syndrome
The prevalence of essential hypertension complicated with obstructive sleep apnea hypopnea syndrome (OSAHS) has been increasing year by year. However, due to the differences in medical conditions and lack of clinical understanding in different regions of China, the diagnosis of hypertension complicated with OSAHS is still insufficient. Relevant studies have shown that the pathogenesis of hypertension complicated with OSAHS is closely related to the ectopic accumulation of fat and insulin resistance.
This study attempted to analyze the relationship between OSAHS and abdominal visceral adipose tissue (VAT) and homeostasis model assessment of insulin resistance (HOMA-IR) , and their predictive value for hypertension complicated with OSAHS.
Two hundred and thirty-four patients with essential hypertension treated at hypertension center of Yan'an Hospital of Kunming Medical University from January 2019 to July 2020 were enrolled in the study. The HOMA-IR of the enrolled patients was calculated by polysomnography, VAT measurement, parallel glucose tolerance and insulin release experiments. According to the AHI level, 27 patients were divided into hypertension group (AHI<5 times/h) , and 207 patients were divided into hypertension complicated with OSAHS group (AHI≥5 times/h) . The levels of VAT and HOMA-IR were compared between 2 groups. The receiver operating characteristic (ROC) curve of screening hypertension patients complicated with OSAHS were determined by HOMA-IR and VAT, and the diagnosis value of area under AUC and different cut-off value were calculated. Logistic regression modeling was used to determine ROC curve with the saved probability as a separate variable to analyze the AUC of the two combined diagnosis of hypertension and OSAHS.
The VAT, HOMA-IR and BMI of hypertension complicated with OSAHS group were significantly higher than the hypertension group, while LSaO2 was significantly lower than the hypertension group. VAT, HOMA-IR and BMI were positively correlated with AHI (P<0.05) , and LSaO2 was negatively correlated with AHI (P<0.05) . The AUC of ROC curve for the diagnosis of hypertension complicated with OSAHS by VAT was 0.905 〔95%CI (0.861, 0.949) 〕, and the sensitivity and specificity were 0.763 and 0.926 when the diagnostic cut-off point was 100.5 cm2. The ROC curve AUC of HOMA-IR in the diagnosis of hypertension complicated with OSAHS was 0.813 〔95%CI (0.725, 0.900) 〕, when the diagnostic cut-off point was 2.015, the sensitivity and specificity were 0.797 and 0.778, respectively, and the AUC of ROC curve for combined factor diagnosis of hypertension complicated with OSAHS was 0.917 〔95%CI (0.871, 0.963) 〕, the diagnostic cut-off point was 2.045, the sensitivity and specificity were 0.831 and 0.963, respectively.
VAT and HOMA-IR in hypertension patients complicated with OSAHS are significantly higher than those in patients with hypertension. VAT and HOMA-IR have a certain predictive value for hypertension complicated with OSAHS, and can be applied to medical institutions that unconditionally carry out polysomnography, in order to intervene as early as possible to reduce the risk of serious complications of cardiovascular and cerebrovascular diseases.
