Effects of childhood obstructive sleep apnea with and without daytime sleepiness on behaviors and emotions.

OBJECTIVE: To investigate the relationship between obstructive sleep apnea (OSA) with and without excessive daytime sleepiness (EDS) and behavioral and emotional outcomes in non-obese prepubertal children. METHODS: This was a retrospective analysis of children aged 5-11 years who presented to our unit for assessment of their sleep-related complaints. All children underwent polysomnography (PSG). They also completed the Pediatric Daytime Sleepiness Scale (PDSS) and a sleep diary. OSA was diagnosed if the obstructive apnea-hypopnea index (OAHI) was ≥1 event/hour. EDS was defined as PDSS >15. Behavioral and emotional outcomes were assessed using the Child Behavioral Checklist (CBCL). RESULTS: Data from 391 children (mean age of 8.6 ± 1.7 years; 67 % male) were analyzed. Seventy children did not have OSA or EDS, 137 had OSA, 50 had reported having EDS but without OSA, and 134 children had both OSA and EDS. There were significantly higher CBCL total problems score in the combined group (61 ± 9) compared to the non-OSA/EDS group (54 ± 10), and the OSA-only group (54 ± 10) (p < 0.001). The presence of EDS was significantly associated with higher CBCL T score and higher odds for clinically significant behavioral problems (T score ≥65) after adjusting for age, sex, BMI z-score and average sleep duration (p < 0.001). CONCLUSION: Excessive daytime sleepiness is an important contributory factor associated with suboptimal behavioral and emotional outcomes in children with OSA.

Applicability of the Global Lung Function Initiative prediction equations in Hong Kong Chinese children.

BACKGROUND AND OBJECTIVE: This study aimed to assess the applicability of the Global Lung Function Initiative (GLI) prediction equations for spirometry in Hong Kong children and to develop prediction equations based on the Generalized Additive Models for Location, Scale, and Shape (GAMLSS) modeling. METHODS: Healthy Chinese children and adolescents aged 6-17 years old were recruited from randomly selected schools to undergo spirometry. The measurements were transformed to z-score according to the GLI-2012 equations for South East (SE) Asians and the GLI-2022 global race-neutral equations. Prediction equations for spirometric indices were developed with GAMLSS modeling to identify predictors. RESULTS: A total of 886 children (477 boys) with a mean age of 12.5 years (standard deviation [SD] 3.3 years) were included. By the GLI-2012 SE Asian equations, positive mean z-scores were observed in forced expiratory volume in 1 s (FEV1 ) (boys: 0.138 ± SD 0.828; girls: 0.206 ± 0.823) and forced vital capacity (FVC) (boys: 0.160 ± 0.930; girls: 0.310 ± 0.895) in both sexes. Negative mean z-scores were observed in FEV1 /FVC ratio (boys: -0.018 ± 0.998; girls: -0.223 ± 0.897). In contrast, negative mean z-scores in FEV1 and FVC, and positive mean z-scores in FEV1 /FVC were observed when adopting the GLI-2022 race-neutral equations. The mean z-scores were all within the range of ±0.5. By GAMLSS models, age and height were significant predictors for all four spirometric indices, while weight was an additional predictor for FVC and FEV1 . CONCLUSION: Our study provided data supporting the applicability of the GLI prediction equations in Hong Kong Chinese children. The GLI-2012 equations may underestimate FEV1 and FVC, while the GLI-2022 equations may overestimate the parameters, but the differences lie within the physiological limits. By GAMLSS modeling, weight was an additional predictor for FVC and FEV1 .

Craniofacial phenotyping by photogrammetry in Chinese prepubertal children with obstructive sleep apnea.

STUDY OBJECTIVES: This study aimed to examine the craniofacial phenotype of Chinese prepubertal children with and without obstructive sleep apnea (OSA) using a quantitative photographic analysis technique and to develop a prediction model for OSA diagnosis based on the photogrammetric data. Potential ethnic differences in the association between OSA and photogrammetric data between Chinese and Caucasian children were also examined. METHODS: This was a cross-sectional study. Chinese children aged 5-12 years old, suspected to have OSA were recruited from our sleep clinic. Frontal and side photos were taken for craniofacial phenotyping by photogrammetry. Polysomnography was performed and participants were divided into three groups: non-OSA (obstructive apnea hypopnea index (OAHI) < 1/h), mild OSA (OAHI between 1/h and 5/h), and moderate-to-severe (MS) OSA (OAHI ≥ 5/h). Prediction models were built from 70% of training data using logistic regression and evaluated on the remaining 30% of test data for receiver operating characteristic (ROC) curve construction. RESULTS: This study included 90 participants (mean age: 8.2 ± 1.6 years, 67 males). Non-OSA, mild OSA, and MS OSA groups included 32, 31, and 27 participants, respectively. There were significant trends for an increasing maxillary-mandibular relationship angle (p = .002) and a decreasing anterior mandibular height to whole face length ratio (p < .001) with increasing OSA severity. A prediction model built with clinical measurements and the two photogrammetric features yielded an area under the ROC curve (AUC) of 0.81 (95% C.I.: 0.64-0.96). CONCLUSIONS: Craniofacial features obtained by photogrammetry are significantly different between OSA groups in prepubertal children. Increased maxillary-mandibular relationship angle is an OSA feature found in both Asian and Caucasian children.

Validation of the Sonographic Measurement of Lateral Parapharyngeal Wall Thickness in Childhood Obstructive Sleep Apnea.

Background: Lateral parapharyngeal wall (LPW) thickness is a potentially useful anatomical marker of childhood obstructive sleep apnea (OSA). Measuring LPW thickness by ultrasonography (USG) is technically feasible but its use in children has not been validated. Therefore, this study aimed to assess the intra- and inter-operator reliability of the sonographic measurements of LPW thickness in children and to assess its validity against magnetic resonance imaging (MRI) measurements. Methods: Prepubertal children aged 6-11 years suspected to suffer from OSA were recruited. Repeated measurements of LPW thickness by USG were conducted to evaluate the intra- and inter-operator reliability, examined by intraclass correlation coefficient (ICC). LPW thickness was measured as the distance between the internal carotid artery and the echogenic surface of the pharynx in an oblique coronal plane by USG. LPW thickness was measured by MRI at the retropalatal level. The agreement between the LPW thickness measured by USG and MRI was assessed by ICC and Bland-Altman plot. Results: Thirty-four children (mean age: 8.66 ± 1.61, 26 male) were recruited. The intra- and inter-operator reliability of the LPW thickness by USG was good (ICC = 0.84 and 0.82, respectively). The agreement between the USG-measured and MRI-measured LPW thickness was moderate (ICC = 0.72). he Bland-Altman plot demonstrated a mean difference of 0.061 cm and a 95% limit of agreement from 0.91 to 1.12 cm. Conclusion: In this study, we demonstrated that ultrasonography is a valid and reliable method to assess LPW thickness in children. This study was supported by the Direct Grant for Research from the Research Committee of the Chinese University of Hong Kong (Project no. 2020.073).

Expression, secretion and functional characterization of three laccases in E. coli.

Endocrine Disrupting Chemicals (EDCs) are a group of molecules that can influence hormonal balance, causing disturbance of the reproductive system and other health problems. Despite the efforts to eliminate EDC in the environment, all current approaches are inefficient and expensive. In previous research, studies revealed that laccase-producing microorganisms may be a potential candidate for EDC degradation, as laccases have been found to be able to degrade many kinds of EDCs effectively and steadily. Here, we created two recombinant laccases, each fused with secretion peptide, Novel Signal Peptide 4 (NSP4), and expressed them in Escherichia coli (E. coli, BL21), together with one laccase without secretion peptide. We first optimized the culture condition of expressing these laccases. Then, we test the activity of the recombinant laccases of decolorizing of a synthetic dye, indigo carmine. Finally, we confirmed the secreted can degrade one of the EDCs, ß-estradiol, showing the potential of using the laccase secretion system to degrade toxic compounds.

Reduced tongue mobility: an unrecognized risk factor of childhood obstructive sleep apnea.

STUDY OBJECTIVES: Childhood obstructive sleep apnea (OSA) is an important and prevalent disease. A short lingual frenulum is a risk factor for OSA, but whether tongue mobility also plays a role in OSA etiology remains unknown. This study aimed to examine tongue mobility in children with and without OSA. We hypothesized that reduced tongue mobility was associated with OSA. We also evaluated the relationship between tongue mobility and craniofacial profile. METHODS: This was a cross-sectional case-control study. Prepubertal Chinese children aged 5-12 years, suspected to have OSA were recruited from our sleep disorder clinic. All subjects underwent overnight polysomnography. The lingual frenulum was evaluated based on tongue mobility and free tongue length. Craniofacial measurements were assessed by lateral cephalometry. RESULTS: Eighty-two subjects (mean age: 8.32 ± 1.70 years, 57 males) were recruited. The mean tongue mobility was 58.2 (±19)% and 67.4 (±15)% (p = 0.019) in subjects with and without OSA, respectively. Tongue mobility was inversely correlated with OAHI (r = -0.218, p = 0.049). In multivariate logistic regression, low tongue mobility was independently associated with a higher risk of OSA after adjustment for age, sex, body mass index z-score, presence of large tonsils and turbinates, and nocturnal oral breathing (odds ratio = 3.65, 95% CI = 1.22 to 11.8). Tongue mobility was found to correlate with the cranial base angle (Ba-S-N) (r = 0.262, p = 0.018), which determines the relative position of the mandible. CONCLUSIONS: In prepubertal children, reduced tongue mobility is associated with the occurrence and severity of OSA. Assessing tongue mobility is recommended in childhood OSA management.