Dynamics of childhood obesity in Hong Kong throughout the COVID-19 pandemic before and after the school closures: a 3-year longitudinal study

OBJECTIVE

This study is to evaluate if there is any difference in the balance between incidence of and remission from overweight/obesity in Hong Kong school-age children before and during the COVID-19 pandemic over three years.

METHODS

This is a retrospective longitudinal study that involved children aged 6-16 years from a database of the School Physical Fitness Award Scheme.

RESULTS

2765 students were longitudinally followed up for two years. The prevalence of childhood overweight/obesity was increased between the 2019 and 2021 academic years (P < 0.001). During the COVID-19 pandemic, the rate of obesity remission significantly reduced by 7.9 % (P = 0.003), at a background of a plateau of obesity among children and adolescents.

CONCLUSIONS

Our study provides evidence on the impact of school closure and home confinement as a standard infection control measure for the prevention of COVID-19, which are likely to break the balance between incidence of and remission from childhood obesity.

Spiritual and cultural influences on end-of-life care and decision-making in NICU

Understanding and respecting the spiritual beliefs, ethnic roots, cultural norms and customs of individual families is essential for neonatologists to provide clinically appropriate and humane end-of-life care. This review describes the religious/philosophical principles, cultural-related practices/rituals, and traditions in end-of-life care in major spiritual groups of today's multi-cultural, multi-faith societies. The spiritual groups include Christians, Muslims, Jewish Judaism believers and Asian religious/philosophy followers such as Buddhists, Hindus, Taoists, Confucianism devotees and ancestral worshippers. It is vital to understand that substantial variation in views and practices may exist even within the same religion and culture in different geographic locations. Ethical views and cultural practices are not static elements in life but behave in a fluidic and dynamic manner that could change with time. Interestingly, an evolving pattern has been observed in some Asian and Middle East countries that more parents and/or religious groups are beginning to accept a form of redirection of care most compatible with their spiritual belief and culture. Thus, every family must be assessed and counseled individually for end-of-life decision-making. Also, every effort should be made to comply with parents' requests and to treat infants/parents of different religions and cultures with utmost dignity so that they have no regret for their irreversible decisions.

Hypertonic glucose pleurodesis for preterm neonates with chylothorax

Chylothorax is a known complication of postcardiac surgery and the most common cause of pleural effusion in neonates. Conservative management is usually adopted, including Nil-per-Oral (NPO), treatment of underlying etiology of infection, and use of octreotide. Chylothorax resistant to medical therapy and drainage is often treated by chemical pleurodesis. Previously used pleurodesis agents have included talc, minocycline, OK-432, bleomycin, and povidone-iodine. 50% Dextrose (D50) has been reported to be useful for pleurodesis in adults. We successfully managed two cases of prematurely born infants with D50 as an alternative chemical sclerosant for chemical pleurodesis in a resistant chylothorax and discussed evidence of its use in the literature.

Comparison of the mucosal and systemic antibody responses in Covid-19 recovered patients with one dose of mRNA vaccine and unexposed subjects with three doses of mRNA vaccines

Background

Immunity acquired from natural SARS-CoV-2 infection and vaccine wanes overtime. This longitudinal prospective study compared the effect of a booster vaccine (BNT162b2) in inducing the mucosal (nasal) and serological antibody between Covid-19 recovered patients and healthy unexposed subjects with two dose of mRNA vaccine (vaccine-only group).

Method

Eleven recovered patients and eleven gender-and-age matched unexposed subjects who had mRNA vaccines were recruited. The SARS-CoV-2 spike 1 (S1) protein specific IgA, IgG and the ACE2 binding inhibition to the ancestral SARS-CoV-2 and omicron (BA.1) variant receptor binding domain were measured in their nasal epithelial lining fluid and plasma.

Result

In the recovered group, the booster expanded the nasal IgA dominancy inherited from natural infection to IgA and IgG. They also had a higher S1-specific nasal and plasma IgA and IgG levels with a better inhibition against the omicron BA.1 variant and ancestral SARS-CoV-2 when compared with vaccine-only subjects. The nasal S1-specific IgA induced by natural infection lasted longer than those induced by vaccines while the plasma antibodies of both groups maintained at a high level for at least 21 weeks after booster.

Conclusion

The booster benefited all subjects to obtain neutralizing antibody (NAb) against omicron BA.1 variant in plasma while only the Covid-19 recovered subjects had an extra enrichment in nasal NAb against omicron BA.1 variant.

Neonatal mortality in singleton pregnancies: a 20-year retrospective study from a tertiary perinatal unit in Hong Kong

INTRODUCTION

The global neonatal death (NND) rate has been declining in recent decades, but there are no comprehensive data concerning the characteristics of NNDs in Hong Kong. This study investigated the trends and aetiologies of NNDs among singleton pregnancies in Hong Kong.

METHODS

This study included all cases of NND from singleton pregnancies in a tertiary hospital in Hong Kong between 2000 and 2019. The rates, clinical characteristics, and aetiologies of NND were compared between the first (2000-2009) and the second (2010-2019) decades.

RESULTS

The NND rate decreased from 1.66/1000 livebirths (97 cases) in the first decade to 1.32/1000 livebirths (87 cases) in the second decade. Congenital or genetic abnormalities (82 cases) caused 44.6% of all NNDs. There was a significant reduction from 0.82/1000 livebirths in the first decade to 0.52/1000 livebirths in the second decade (P=0.037). Other causes of NND were prematurity (69 cases; 37.5%), sepsis (16 cases; 8.7%), hypoxic-ischaemic encephalopathy (15 cases; 8.2%), and sudden infant death syndrome (2 cases; 1.1%). Gestational age-specific neonatal mortality for moderately preterm neonates (31-33 weeks of gestation) significantly decreased from 34.73/1000 in 2000-2009 to 8.63/1000 in 2010-2019 (P=0.001), but there were no significant changes in neonatal mortality for other gestations.

CONCLUSION

The NND rate in Hong Kong is among the lowest worldwide. Neonatal deaths in our centre declined over the past two decades, mainly because of improvements in the prenatal diagnosis and treatment of congenital or genetic abnormalities, as well as an improved survival rate among moderately preterm neonates.

Age- and Sex-Specific Physical Fitness Reference and Association with Body Mass Index in Hong Kong Chinese Schoolchildren

There is lacking a population-based study on the fitness level of Hong Kong schoolchildren, and it seems that increasing childhood obesity prevalence has shifted the classification of healthy fitness, with 'underfit' as normal. This cross-sectional territory study aimed to develop an age- and sex-specific physical fitness reference using a representative sample of children aged 6-17 and to determine the associations with body mass index in schoolchildren. The study analyzed Hong Kong School Physical Fitness Award Scheme data covering grade 1 to grade 12 students' physical fitness and anthropometric measurements from 2017 to 2018. This reference was established without the impact due to COVID-19. Four aspects of physical fitness tests were measured using a standardized protocol, including (i) upper limb muscle strength, (ii) one-minute sit-up, (iii) sit-and-reach, and (iv) endurance run tests. The generalized additive model for location, scale, and shape was used to construct the reference charts. A Mann-Whitney U test was used to compare the mean differences in age, weight, and height, and a Pearson's chi-square test was used to examine the distributions of sex groups. A Kruskal-Wallis test was used to compare the group differences in BMI status, followed by the Dunn test for pairwise comparisons. A 5% level of significance was regarded as statistically significant. Data of 119,693 students before the COVID-19 pandemic were included in the analysis. The association between physical fitness level and BMI status varied depending on the test used, and there were significant differences in fitness test scores among BMI groups. The mean test scores of the obese group were lower in most of the tests for both boys and girls, except for handgrip strength. The underweight group outperformed the obese group in push-ups, one-minute sit-ups, and endurance run tests, but not in handgrip strength. In conclusion, a sex- and age-specific physical fitness reference value for Hong Kong Chinese children aged 6 to 17 years old is established, and this study demonstrated a nonlinear relationship between BMI status and physical fitness. The reference will help to identify children with poor physical fitness to offer support and guidance on exercise training. It also serves as a baseline for assessing the impact of the COVID-19 pandemic on Hong Kong students' physical fitness.

The view of Hong Kong parents on secondary use of dried blood spots in newborn screening program

Background

Residual dried blood spots (rDBS) from newborn screening programmes represent a valuable resource for medical research, from basic sciences, through clinical to public health. In Hong Kong, there is no legislation for biobanking. Parents’ view on the retention and use of residual newborn blood samples could be cultural-specific and is important to consider for biobanking of rDBS.

Objective

To study the views and concerns on long-term storage and secondary use of rDBS from newborn screening programmes among Hong Kong Chinese parents.

Methods

A mixed-method approach was used to study the views and concerns on long-term storage and secondary use of rDBS from newborn screening programmes among Hong Kong Chinese parents of children 0–3 years or expecting parents through focus groups (8 groups; 33 participants) and a survey (n = 1012, 85% mothers) designed with insights obtained from the focus groups. We used framework analysis to summarise the themes as supportive factors, concerns and critical arguments for retention and secondary use of rDBS from focus group discussion. We used multiple logistic regression to assess factors associated with support for retention and secondary use of rDBS in the survey.

Results

Both in focus groups and survey, majority of parents were not aware of the potential secondary use of rDBS. Overall secondary use of rDBS in medical research was well accepted by a large proportion of Hong Kong parents, even if all potential future research could not be specified in a broad consent. However parents were concerned about potential risks of biobanking rDBS including leaking of data and mis-use of genetic information. Parents wanted to be asked for permission before rDBS are stored and mainly did not accept an “opt-out” approach. The survey showed that parents born in mainland China, compared to Hong Kong born parents, had lower awareness of newborn screening but higher support in biobanking rDBS. Higher education was associated with support in rDBS biobanking only among fathers.

Conclusion

Long-term storage and secondary use of rDBS from newborn screening for biomedical research and a broad consent for biobanking of rDBS are generally acceptable to Hong Kong parents given their autonomy is respected and their privacy is protected, highlighting the importance of an accountable governance and a transparent access policy for rDBS biobanks.

Perinatal mortality rate in multiple pregnancies: a 20-year retrospective study from a tertiary obstetric unit in Hong Kong

INTRODUCTION

Multiple pregnancies have become more common, but their perinatal mortality rate remains higher than the rate among singleton pregnancies. This retrospective study investigated the prevalence and causes of perinatal mortality among multiple pregnancies in Hong Kong.

METHODS

All multiple pregnancies in a university tertiary obstetric unit between 2000 and 2019 were reviewed, and the medical records of cases complicated by stillbirth and neonatal death were identified. The causes of perinatal mortality were determined based on clinical assessment and laboratory results, then compared between the first (2000-2009) and second (2010-2019) decades.

RESULTS

The prevalence of multiple pregnancies increased from 1.41% in the first decade to 1.91% in the second decade (P<0.001). Compared with the first decade, the second decade had a lower stillbirth rate (14.72 vs 7.68 [both per 1000 births]; P=0.026), late neonatal death rate (4.78 vs 1.16 [both per 1000 livebirths]; P=0.030), and total mortality rate (25.32 vs 13.82 [both per 1000 births]; P=0.006). The decline in stillbirth rate was related to improvements in antenatal care and treatment. The decline in the late neonatal death rate was related to a reduction in preterm birth before 34 weeks (18.5% vs 15.2%; P=0.006), as well as an improvement in the mortality rate in the subgroup of 31-33 weeks (19.23 vs 0 [both per 1000 livebirths]; P=0.035).

CONCLUSION

Although the prevalence of multiple pregnancies increased during the study period, the corresponding total perinatal mortality rate improved by 45.4%.

Comorbidity of ADHD and allergic diseases in early adolescence: The role of parental smoking at home

A growing body of research suggests an association between attention deficit hyperactivity disorder (ADHD) and allergic disorders, but little work has been done to explore the role of external factors such as parental smoking at home in the development of comorbid ADHD and allergic disorders. This study aimed to examine the association between allergic diseases and ADHD adjusted for exposure to parental smoking at home in early adolescents. We recruited 250 male (41.7%) and 350 female (58.3%) adolescents (mean [SD] age, 13.29 [0.52] years) via chain-referral sampling. Their ADHD symptoms were assessed by the parent proxy-report version of the Chinese Strengths and Weaknesses of Attention-Deficit/Hyperactivity-symptoms and Normal-behaviours (SWAN) rating scale. Data on the participants' history of clinician-diagnosed allergic diseases, family socio-demographics, and parental smoking habit were collected using a parent-completed questionnaire. Regression analyses were performed to examine the associations of interest. The levels of ADHD symptoms were comparable between allergic and non-allergic participants after controlling for child and family demographics and parental smoking at home. Notably, the risk of probable ADHD was particularly high in participants with food allergies (odd ratio = 4.51, p = 0.011) but not in those with allergic rhinitis after adjusting for parental smoking at home. Our findings suggest that second-hand smoke exposure at home is a potential risk factor underlying the link between ADHD and allergic diseases. Current management guidelines should emphasize the importance of early identification and cessation of tobacco smoke exposure for prevention of comorbidity of ADHD and allergic disorders. Clinical Trial Registration (if any): NA.

The Mucosal and Serological Immune Responses to the Novel Coronavirus (SARS-CoV-2) Vaccines

Background

Although the serological antibody responses induced by SARS-CoV-2 vaccines are well characterized, little is known about their ability to elicit mucosal immunity.

Objectives

This study aims to examine and compare the mucosal and systemic responses of recipients of two different vaccination platforms: mRNA (Comirnaty) and inactivated virus (CoronaVac).

Methods

Serial blood and nasal epithelial lining fluid (NELF) samples were collected from the recipients of either Comirnaty or CoronaVac. The plasma and NELF immunoglobulins A and G (IgA and IgG) specific to SARS-CoV-2 S1 protein (S1) and their neutralization effects were quantified.

Results

Comirnaty induced nasal S1-specific immunoglobulin responses, which were evident as early as 14 ± 2 days after the first dose. In 64% of the subjects, the neutralizing effects of NELF persisted for at least 50 days. Moreover, 85% of Comirnaty recipients exhibited S1-specific IgA and IgG responses in plasma by 14 ± 2 days after the first dose. By 7 ± 2 days after the booster, all plasma samples possessed S1-specific IgA and IgG responses and were neutralizing. The induction of S1-specific plasma antibodies by CoronaVac was IgG dominant, and 83% of the subjects possessed S1-specific IgG by 7 ± 2 days after the booster, with neutralizing effects.

Conclusion

Comirnaty induces S1-specific IgA and IgG responses with neutralizing activity in the nasal mucosa; a similar response is not seen with CoronaVac.

Clinical Implication

The presence of a nasal response with mRNA vaccine may provide additional protection compared with inactivated virus vaccine. However, whether such widespread immunological response may produce inadvertent adverse effects in other tissues warrants further investigation.

Randomised controlled trial: Can topical timolol maleate prevent complications for small superficial infantile haemangiomata in high-risk areas?

BACKGROUND

To define the role of topical timolol maleate (TTM) in the treatment of infantile haemangiomata (IH).

METHODS

In this single-centre randomised controlled trial, we included all <1-year-old infants within a 13-month period presenting with small (<2 cm) superficial IH located at high-risk areas (i.e. tip of ears, tip of nose, eyelids, acral areas, facial areas, scalp, neck, buttocks, perineum and axilla). Patients either received 12 months of 0.5% TTM solution (study group) or watchful waiting (control group). The primary outcome was IH with development of complications that required additional interventions. The secondary outcomes included side effects of TTM and change in IH size.

RESULTS

Forty-two children were eligible to the study. Patients who received TTM were noted to have significantly fewer complications than the control group (4.2% versus 29%, odds ratio 9.58 [95% confidence interval: 1.01-91.62], p = 0.04). Mean IH volume percentage reduction was significantly more for the TTM group and no-TTM group at 3, 6 and 12 months.

CONCLUSIONS

TTM is an effective and safe treatment option to reduce complications, IH volume and the need for further intervention for infants with small superficial IH located at high-risk areas.

IMPACT

There is a lack of reliable signs to predict ulceration, disfigurement and other complications for high-risk IH. Treatment options range from watchful waiting to early systemic treatment, with TTM a novel and promising treatment. The exact role of TTM remains unanswered due to a lack of evidence-based research. TTM is effective and safe for infants with superficial IH of <2 cm in high-risk areas. Early TTM use on IH can reduce complications, IH volume and the need for further treatment.

The KLHL40 c.1516A>C is a Chinese-specific founder mutation causing nemaline myopathy 8: Report of six patients with pre- and postnatal phenotypes

Background

Autosomal recessive or compound heterozygous mutations in KLHL40 cause nemaline myopathy 8, which is one of the most severe forms of nemaline myopathy. The KLHL40 c.1516A>C variant has recently been reported as a founder mutation in southern Chinese.

Methods

We report six cases of nemaline myopathy 8 which involves the c.1516A>C variant, from five unrelated families of non‐consanguineous southern Chinese. The pre‐ and postnatal phenotypes of these cases were reviewed with emphasis on prenatal clinical features. Genetic testing for the founder mutation was performed on three patients with homozygous mutations.

Results

Common prenatal features included reduced fetal movement, polyhydramnios, breech presentation, and clubfeet. Two pregnancies were terminated. Four live‐born patients had postnatal features typical of nemaline myopathy 8. The length of survival ranged from 49 days to 17 months, with respiratory failure and infections being the principal causes of death. Haplotype analysis in three patients with homozygous mutation showed a shared haplotype block of 1.1727 cM spanning over the c.1516A>C variant, suggesting it is a southern Chinese‐specific founder mutation.

Conclusion

Analysis of the KLHL40 c.1516A>C variant should be considered in prenatal diagnosis of Chinese pregnant patients with suspected congenital neuromuscular disorders or with significant family history of congenital myopathies.

Does gestational diabetes mellitus affect respiratory outcome in late-preterm infants?

BACKGROUND

Both gestational diabetes mellitus (GDM) and late-preterm delivery at 34-36 weeks' gestation are independently associated with neonatal respiratory complications, but it is unknown whether their combination increases further its risk. We therefore appraised the independent effect of GDM on the respiratory outcome of late-preterm infants.

METHODS

In a retrospective cohort study, respiratory outcome of 911 infants delivered at 34-36 weeks' gestation between 1 January 2009 and 30 August 2012 from mothers with GDM (study group, n=130) was compared with infants delivered at the same gestation by mothers without GDM (control group, n=781).

RESULTS

The study group had significantly higher incidence of transient tachypnoea of newborn (TTN, p=0.02) and air leak (p=0.012), and required more respiratory support, including oxygen, continuous positive airway pressure (CPAP), mechanical ventilation and neonatal intensive care, with a longer length of hospital stay, but not duration on respiratory support. On logistic regression analysis, GDM is an independent risk factor for TTN (aOR=1.5, 95% C.I.1.0-2.4), CPAP (aOR=2.37, 95% C.I. 1.05-4.89), mechanical ventilation (aOR=4.02 95% C.I. 1.57-10.32) and neonatal intensive care (aOR 1.83, 95% C.I. 1.05-3.87).

CONCLUSIONS

Our results demonstrated an independent effect of GDM on the risk of severe respiratory complications in late-preterm infants. Additional close monitoring and timely intervention are necessary in the management of these infants.

Infants born to mothers with severe acute respiratory syndrome

Severe acute respiratory syndrome (SARS) is a newly discovered infectious disease caused by a novel coronavirus. During the community outbreak in Hong Kong, 5 liveborn infants were born to pregnant women with SARS. A systematic search for perinatal transmission of the SARS-associated coronavirus, including serial reverse transcriptase-polymerase chain reaction assays, viral cultures, and paired serologic titers, failed to detect the virus in any of the infants. In addition, none of the infants developed clinical, radiologic, hematologic, or biochemical evidence suggestive of SARS. One preterm infant developed jejunal perforation and another developed necrotizing enterocolitis with ileal perforation shortly after birth. This case series is the first report to describe the clinical course of the first cohort of liveborn infants born to pregnant women with SARS.