Obstructive sleep apnea and metabolic disorders in morbidly obese adolescents

Persistent sleep-disordered breathing independently contributes to metabolic syndrome in prepubertal children

BACKGROUND

Obstructive sleep apnea (OSA) is a risk factor for metabolic syndrome (MetS) in adults, but its association in prepubertal children is still questionable due to the relatively limited cardiometabolic data available and the phenotypic heterogeneity.

OBJECTIVE

To identify the role of OSA as a potential mediator of MetS in prepubertal children.

METHODS

A total of 255 prepubertal children from the Childhood Adenotonsillectomy Trial were included, with standardized measurements taken before OSA treatment and 7 months later. MetS was defined if three or more of the following criteria were present: adiposity, high blood pressure, elevated glycemia, and dyslipidemia. A causal mediation analysis was conducted to assess the effect of OSA treatment on MetS.

RESULTS

OSA treatment significantly impacted MetS, with the apnea-hypopnea index emerging as mediator (p = .02). This mediation role was not detected for any of the individual risk factors that define MetS. We further found that the relationship between MetS and OSA is ascribable to respiratory disturbance caused by the apnea episodes, while systemic inflammation as measured by C-reactive protein, is mediated by desaturation events and fragmented sleep. In terms of evolution, patients with MetS were significantly more likely to recover after OSA treatment (odds ratio = 2.56, 95% confidence interval [CI] 1.20-5.46; risk ratio = 2.06, 95% CI 1.19-3.54) than the opposite, patients without MetS to develop it.

CONCLUSION

The findings point to a causal role of OSA in the development of metabolic dysfunction, suggesting that persistent OSA may increase the risk of MetS in prepubertal children. This mediation role implies a need for developing screening for MetS in children presenting OSA symptoms.

The potential of tRF-21-U0EZY9X1B plasmatic level as a biomarker of children with obstructive sleep apnea-hypopnea syndrome

PURPOSE

We investigated changes in plasma transfer RNA related fragments (tRF) in children with obstructive sleep apnea-hypopnea syndrome (OSAHS) and the potential value as a disease marker.

METHODS

Firstly, we randomly selected five plasma samples from the case group and the control group for high-throughput RNA sequencing. Secondly, we screened one tRF with different expression between the two groups, amplified it by quantitative reverse transcription-PCR (qRT-PCR) and sequenced the amplified product. After confirming that the qRT-PCR results were consistent with the sequencing results and the sequence of the amplified product contained the original sequence of the tRF, we performed qRT-PCR on all samples. Then we analyzed the diagnostic value of the tRF and its correlation with some clinical data.

RESULTS

A total of 50 OSAHS children and 38 control children were included in this study. There were significant differences in height, serum creatinine (SCR) and total cholesterol (TC) between the two groups. The plasma expression levels of tRF-21-U0EZY9X1B (tRF-21) were significantly different between the two groups. Receiver operating characteristic curve (ROC) showed that it had valuable diagnostic index, with area under the curve (AUC) of 0.773, 86.71% and 63.16% sensitivity and specificity.

CONCLUSIONS

The expression levels of tRF-21 in the plasma of OSAHS children decreased significantly which were closely related to hemoglobin, mean corpuscular hemoglobin, triglyceride and creatine kinase-MB, may become novel biomarkers for the diagnosis of pediatric OSAHS.

Prediction of thirty-day morbidity and mortality after duodenal switch using an artificial neural network

BACKGROUND

Understanding factors that increase risk of both mortality and specific measures of morbidity after duodenal switch (DS) is important in deciding to offer this weight loss operation. Artificial neural networks (ANN) are computational deep learning approaches that model complex interactions among input factors to optimally predict an outcome. Here, a comprehensive national database is examined for patient factors associated with poor outcomes, while comparing the performance of multivariate logistic regression and ANN models in predicting these outcomes.

METHODS

2907 DS patients from the 2019 Metabolic and Bariatric Surgery Accreditation and Quality Improvement Program database were assessed for patient factors associated with the previously validated composite endpoint of 30-day postoperative reintervention, reoperation, readmission, or mortality using bivariate analysis. Variables associated (P ≤ 0.05) with the endpoint were imputed in a multivariate logistic regression model and a three-node ANN with 20% holdback for validation. Goodness-of-fit was assessed using area under receiver operating curves (AUROC).

RESULTS

There were 229 DS patients with the composite endpoint (7.9%), and 12 mortalities (0.4%). Associated patient factors on bivariate analysis included advanced age, non-white race, cardiac history, hypertension requiring 3 + medications (HTN), previous foregut/obesity surgery, obstructive sleep apnea (OSA), and higher creatinine (P ≤ 0.05). Upon multivariate analysis, independently associated factors were non-white race (odds ratio 1.40; P = 0.075), HTN (1.55; P = 0.038), previous foregut/bariatric surgery (1.43; P = 0.041), and OSA (1.46; P = 0.018). The nominal logistic regression multivariate analysis (n = 2330; R² = 0.02, P < 0.001) and ANN (R² = 0.06; n = 1863 [training set], n = 467 [validation]) models generated AUROCs of 0.619, 0.656 (training set) and 0.685 (validation set), respectively.

CONCLUSION

Readily obtainable patient factors were identified that confer increased risk of the 30-day composite endpoint after DS. Moreover, use of an ANN to model these factors may optimize prediction of this outcome. This information provides useful guidance to bariatricians and surgical candidates alike.

Obstructive sleep apnea and anatomical structures of the nasomaxillary complex in adolescents

The aim of the present study was to reveal the associations between skeletal and soft tissue features of the nasomaxillary complex and development and severity of obstructive sleep apnea (OSA) in adolescents. A total of 100 adolescents (mean age, 14.9 ± 1.4 years; age range, 13–17 years) were enrolled. All participants underwent full-night polysomnography and had an assessment of size and position of the tongue, tonsillar size, body mass index (BMI), and circumference of the waist, neck, and hip. The skeletal features of the nasomaxillary complex, including the zygomatic arch width, nasal cavity width, nasal base width, intercanine width, intermolar width, maxillary dental arch length, palatal vault angle, palatal depth, and SNA were measured on the three-dimensional images constructed with computed tomography data. Participants with an apnea and hypopnea index (AHI) of lower than 5 (AHI ≤ 5) were classified as control and participants while those with an AHI of greater than 5 were classified as OSA group. Each variable with a significant outcome in the independent T-test and age and sex factors were integrated into the multivariate linear regression and the dependent variable was AHI. There were significant differences in the BMI and hip circumference between two groups. The width of nasal base, palatal vault angle and SNA also showed significant differences between groups. The results from multivariate linear regression demonstrated that the BMI, width of the nasal base, and SNA showed significant contributions to the severity of OSA in adolescents. The features of the nasomaxillary complex seemed to have significant influences on development and severity of OSA.

Serum Transferrin Level Is Associated with the Severity of Obstructive Sleep Apnea Independently of Obesity: A Propensity Score-Match Observational Study

INTRODUCTION

Dysregulation of iron metabolism is closely associated with the development of obesity and obstructive sleep apnea (OSA), but little is known about the relationship between serum transferrin (TF) level and OSA severity. We aimed to verify this relationship and fit into account for obesity-related confounders among bariatric candidates.

METHODS

We compared data retrospectively collected in 270 bariatric candidates. A propensity score-matched (PSM) analysis was used to determine the impact of iron metabolism on OSA severity independently of obesity. Univariate analysis was used to evaluate the relationship between serum TF level and the severity of OSA reflected by hypoxia and night awakenings parameters. Serum TF level to predict the severity of OSA was assessed by using univariate and multiple logistic regression model.

RESULTS

The preliminary analysis showed that serum ferritin (113 ng/mL [50-203] vs. 79 ng/mL [40-130], p = 0.009) and TF (2.72 g/L [2.46-3.09] vs. 2.65 g/L [2.34-2.93], p = 0.039) level was significantly higher in the moderate/severe OSA group than the no/mild OSA group. After PSM analysis, there were 75 patients in each group and only serum TF level remained significant (p = 0.014). The proportion of patients with combined T2D and hyperlipidemia also remained higher in moderate/severe OSA groups. Univariate analysis showed that the group with higher degree of hypoxia had higher serum TF levels no matter the severity of OSA was grouped by oxygen desaturation index (ODI; 2.79 g/L [2.56-3.06] vs. 2.55 g/L [2.22-2.84], p < 0.001) or minimum oxygen saturation (SpO2nadir; 2.75 g/L [2.50-3.03] vs. 2.56 g/L [2.24-2.92], p = 0.009). Univariate and multiple logistic regression analysis further showed that serum TF level emerged as a significant and independent factor associated with OSA severity especially grouped by ODI (odds ratio: 2.91, 95% CI: 1.36-6.23, p = 0.006).

CONCLUSION

The existence of OSA exacerbates obesity comorbidities, particularly type 2 diabetes and hyperlipidemia. Serum TF level is associated with the severity of OSA independently of obesity and might be a potential identification and therapeutic targets.