Severe early lower respiratory tract infection is associated with subsequent respiratory morbidity in preschool Inuit children in Nunavut, Canada

Respiratory health and its determinants among Nunavimmiut: results from the Qanuilirpitaa? 2017 Nunavik Health Survey

OBJECTIVES

Respiratory diseases are the leading cause of hospitalization in Nunavik (northern Québec, Canada) and contribute to disparities in life expectancy with the rest of Canada. As part of Qanuilirpitaa? 2017, a cross-sectional population-based health survey, we sought to describe the prevalence of respiratory health indicators, including the first estimate of airway obstruction based on spirometry in an Inuit population, and explore their associated characteristics.

METHODS

We analyzed data from 1296 participants aged 16 years and older, using multivariate logistic regression to assess characteristics associated with spirometry-determined airway obstruction and self-reported respiratory symptoms, i.e., wheezing in the last year and chronic cough during at least 3 months.

RESULTS

In this relatively young population (83% aged 16 to 54), the prevalences of wheezing, chronic cough, and airway obstruction were, respectively, 27% (95% CI 24-30), 21% (18-23), and 17% (14-20). These estimates are prone to biases due to the relatively low participation rate (about 37%). The most consistent associations were with smoking (≥ 15 pack-years; odds ratio [OR] 3.13, 3.39, and 2.86 for the three indicators, respectively) and food security (OR 0.55 with wheezing and OR 0.26 with chronic cough), as defined in the Household Food Security Survey Module. Wheezing was also associated with allergic sensitization to dogs (2.60) and obesity (2.18). Chronic cough was associated with respiratory infections during childhood (2.12), housing in need of major repairs (1.72), and housing crowding (1.50), and was negatively associated with participation to traditional activities (0.62) and going on the land (0.64). Airway obstruction was associated with being underweight (3.84) and post-secondary education (0.40). Among young adults and women, wheezing was also associated with any inhalation of solvents for recreational purposes during their lifetime (2.62 and 1.56, respectively), while airway obstruction was associated with regular marijuana use (2.22 and 1.84, respectively).

CONCLUSION

Smoking and food insecurity are both highly prevalent and strongly associated with respiratory symptoms in Nunavik. Together with essential smoking prevention and cessation programs, our findings suggest that solving food security and housing crises, improving socioeconomic conditions, and promoting traditional lifestyle may improve respiratory health in Nunavik.

Deletions in DNAL1 Cause Primary Ciliary Dyskinesia Across North American Indigenous Populations

We report 4 cases of primary ciliary dyskinesia in unrelated indigenous North American children caused by identical, homozygous, likely pathogenic deletions in the DNAL1 gene. These shared DNAL1 deletions among dispersed indigenous populations suggest that primary ciliary dyskinesia accounts for more lung disease with bronchiectasis than previously recognized in indigenous North Americans.

Risk Factors Affecting Development and Persistence of Preschool Wheezing: Consensus Document of the Emilia-Romagna Asthma (ERA) Study Group

Wheezing at preschool age (i.e., before the age of six) is common, occurring in about 30% of children before the age of three. In terms of health care burden, preschool children with wheeze show double the rate of access to the emergency department and five times the rate of hospital admissions compared with school-age asthmatics. The consensus document aims to analyse the underlying mechanisms involved in the pathogenesis of preschool wheezing and define the risk factors (i.e., allergy, atopy, infection, bronchiolitis, genetics, indoor and outdoor pollution, tobacco smoke exposure, obesity, prematurity) and the protective factors (i.e., probiotics, breastfeeding, vitamin D, influenza vaccination, non-specific immunomodulators) associated with the development of the disease in the young child. A multidisciplinary panel of experts from the Emilia-Romagna Region, Italy, addressed twelve key questions regarding managing preschool wheezing. Clinical questions have been formulated by the expert panel using the PICO format (Patients, Intervention, Comparison, Outcomes). Systematic reviews have been conducted on PubMed to answer these specific questions and formulate recommendations. The GRADE approach has been used for each selected paper to assess the quality of the evidence and the degree of recommendations. Based on a panel of experts and extensive updated literature, this consensus document provides insight into the pathogenesis, risk and protective factors associated with the development and persistence of preschool wheezing. Undoubtedly, more research is needed to improve our understanding of the disease and confirm the associations between certain factors and the risk of wheezing in early life. In addition, preventive strategies must be promoted to avoid children's exposure to risk factors that may permanently affect respiratory health.

Shifting paradigm from biomedical to decolonised methods in Inuit public health research in Canada: a scoping review

Background

The National Inuit Strategy on Research focuses on advancing Inuit governance in research, increasing ownership over data and building capacity. Responding to this call for Inuit self-determination in research, academic researchers should consider cultural safety in research and ways to promote Inuit-led methods.

Methods

This scoping review collated academic literature on public health research in Inuit communities in Canada between 2010 and 2022. A critical assessment of methods used in public health research in Inuit communities examined cultural safety and the use of Inuit-attuned methods. Descriptive and analytical data were summarised in tables and figures. Knowledge user engagement in the research process was analysed with thematic analysis.

Results

356 articles met the inclusion criteria. Much of the published research was in nutrition and mental health, and few initiatives reported translation into promotion programmes. Almost all published research was disease or deficit focused and based on a biomedical paradigm, especially in toxicology, maternal health and chronic diseases. Recent years saw an increased number of participatory studies using a decolonial lens and focusing on resilience. While some qualitative research referred to Inuit methodologies and engaged communities in the research process, most quantitative research was not culturally safe. Overall, community engagement remained in early stages of co-designing research protocols and interventions. Discussion on governance and data ownership was limited. Recent years saw emerging discussions on these issues. Knowledge user capacity-building was limited to brief training on conventional data collection methods.

Conclusions

The last decade of published public health research has not responded to the National Inuit Strategy on Research. Participatory research is gaining ground, but has not reached its full potential. A shift from biomedical to decolonised methods is slowly taking place, and public health researchers who have not yet embraced this paradigm shift should do so.

Early-Life Exposure to Environmental Contaminants Perturbs the Sperm Epigenome and Induces Negative Pregnancy Outcomes for Three Generations via the Paternal Lineage

Due to the grasshopper effect, the Arctic food chain in Canada is contaminated with persistent organic pollutants (POPs) of industrial origin, including polychlorinated biphenyls and organochlorine pesticides. Exposure to POPs may be a contributor to the greater incidence of poor fetal growth, placental abnormalities, stillbirths, congenital defects and shortened lifespan in the Inuit population compared to non-Aboriginal Canadians. Although maternal exposure to POPs is well established to harm pregnancy outcomes, paternal transmission of the effects of POPs is a possibility that has not been well investigated. We used a rat model to test the hypothesis that exposure to POPs during gestation and suckling leads to developmental defects that are transmitted to subsequent generations via the male lineage. Indeed, developmental exposure to an environmentally relevant Arctic POPs mixture impaired sperm quality and pregnancy outcomes across two subsequent, unexposed generations and altered sperm DNA methylation, some of which are also observed for two additional generations. Genes corresponding to the altered sperm methylome correspond to health problems encountered in the Inuit population. These findings demonstrate that the paternal methylome is sensitive to the environment and that some perturbations persist for at least two subsequent generations. In conclusion, although many factors influence health, paternal exposure to contaminants plays a heretofore-underappreciated role with sperm DNA methylation contributing to the molecular underpinnings involved.

Impact of home remediation and household education on indoor air quality, respiratory visits and symptoms in Alaska Native children

Alaska Native children experience high rates of lower respiratory tract infections (LRTIs) and lung conditions, which are associated with substandard indoor air quality (IAQ). We conducted an intervention of home remediation and education to assess the impact on IAQ, respiratory symptoms and LRTI visits. We enrolled households of children 1-12 years of age with lung conditions. Home remediation included improving ventilation and replacing leaky woodstoves. We provided education about IAQ and respiratory health. We monitored indoor airborne particles (PM2.5), CO2, relative humidity and volatile organic compounds (VOCs), and interviewed caregivers about children's symptoms before, and for 1 year after intervention. We evaluated the association between children's respiratory visits, symptoms and IAQ indicators using multiple logistic regression. A total of 60 of 63 homes completed the study. VOCs decreased (coefficient = -0.20; p < 0.001); however, PM2.5 (coeff. = -0.010; p = 0.89) did not decrease. Burning wood for heat, VOCs and PM2.5 were associated with respiratory symptoms. After remediation, parents reported decreases in runny nose, cough between colds, wet cough, wheezing with colds, wheezing between colds and school absences. Children had an age-adjusted decrease in LRTI visits (coefficient = -0.33; p = 0.028). Home remediation and education reduced respiratory symptoms, LRTI visits and school absenteeism in children with lung conditions.

The association between environmental tobacco smoke exposure and childhood respiratory disease: a review

INTRODUCTION

Childhood respiratory illness is a major cause of morbidity and mortality particularly in low and middle-income countries. Environmental tobacco smoke (ETS) exposure is a recognised risk factor for both acute and chronic respiratory illness. Areas covered: The aim of this paper was to review the epidemiology of ETS exposure and impact on respiratory health in children. We conducted a search of 3 electronic databases of publications on ETS and childhood respiratory illness from 1990-2015. Key findings were that up to 70% of children are exposed to ETS globally, but under-reporting may mask the true prevalence. Maternal smoking and ETS exposure influence infant lung development and are associated with childhood upper and lower respiratory tract infection, wheezing or asthma. Further, exposure to ETS is associated with more severe respiratory disease. ETS exposure reduces lung function early in life, establishing an increased lifelong risk of poor lung health. Expert commentary: Urgent and effective strategies are needed to decrease ETS exposure in young children to improve child and long-term lung health in adults especially in low and middle income countries where ETS exposure is increasing.

Antibiotics for preventing lower respiratory tract infections in high-risk children aged 12 years and under

BACKGROUND

Lower respiratory tract infections (LRTIs) in young children account for 1.4 million deaths annually worldwide. Antibiotics could be beneficial in preventing LRTIs in high-risk children, and may also help prevent school absenteeism and work days missed by children and/or carers. While it is well documented that the efficacy of antibiotic prophylaxis for RTIs decreases over time, there are no reviews that describe the use of antibiotic prophylaxis to prevent LRTIs in high-risk children aged 12 years and under.

OBJECTIVES

To assess the effectiveness and safety of antibiotic prophylaxis in the prevention of bacterial LRTIs in high-risk children aged 12 years and under.

SEARCH METHODS

We searched the Cochrane Central Register of Controlled Trials (CENTRAL 2015, Issue 1) and the Database of Abstracts of Reviews of Effects (DARE), MEDLINE and MEDLINE In-Process (OvidSP) (1946 to 13 February 2015), EMBASE (OvidSP) (1974 to 12 February 2015), Science Citation Index Expanded (1945 to 13 February 2015) and Conference Proceedings Citation Index-Science (Web of Science Core Collection) (1990 to 13 February 2015). We searched for ongoing studies on ClinicalTrials.gov and the World Health Organization ICTRP. We handsearched the bibliographies of retrieved full texts of relevant studies.

SELECTION CRITERIA

We included randomised controlled trials (RCTs) comparing oral or intravenous antibiotics versus placebo or no treatment to prevent infections in high-risk children aged 12 years and under. We used a combination of the Centers for Disease Control and Prevention (CDC), National Health Service (NHS), American Academy of Paediatrics (AAP) and National Institute for Health and Care Excellence (NICE) guidelines to define conditions at higher risk of complications. Our primary outcome was the incidence of bacterial lower respiratory infections. Secondary outcomes included clinical function, hospital admission, mortality, growth, use of secondary antibiotics, time off school or parental work, quality of life and adverse events.

DATA COLLECTION AND ANALYSIS

We extracted data using a customised data extraction sheet, assessed the risk of bias of included studies using the Cochrane 'Risk of bias' criteria, and used the GRADE criteria to rate the quality of the evidence. We used a random-effects model for meta-analysis. We presented the results narratively where we could not statistically combine data.

MAIN RESULTS

We included 10 RCTs of high-risk children using antibiotics (azithromycin, ciprofloxacin, co-trimoxazole, isoniazid, oral penicillin V or vancomycin) to prevent LRTIs. Three studies included HIV-infected children (n = 1345), four cystic fibrosis (n = 429) and one each sickle cell disease (n = 219), cancer (n = 160) and low birth weight neonates with underlying respiratory disorders (n = 40). The study duration ranged from seven days to three years. The quality of the evidence from studies including children with HIV infection, cystic fibrosis or cancer was moderate. Due to inadequate data, we were unable to rate the quality of the evidence for two studies: one in children with sickle cell disease (low risk of bias), and another in low birth weight neonates with underlying respiratory disorders (high risk of bias).In HIV-infected children receiving continuous isoniazid prophylaxis, there was no significant difference in the incidence of pulmonary tuberculosis (risk ratio (RR) 0.64, 95% confidence interval (CI) 0.32 to 1.29, I(2) statistic = 47%, P value = 0.21). There was no significant effect on mortality with co-trimoxazole or isoniazid prophylaxis (RR 0.82, 0.46 to 1.46, I(2) statistic = 76%, P value = 0.58); however, analysis of one study that used co-trimoxazole showed a significant reduction in mortality (RR 0.67, 95% CI 0.53 to 0.85, P value = 0.001). There was a significant decrease in the rates of hospital admission per child-year of follow-up with co-trimoxazole prophylaxis in one study (P value = 0.01). There was no evidence of increased adverse events due to antibiotic prophylaxis (RR 1.10, 95% CI 0.75 to 1.64, I(2) statistic = 22%, P value = 0.28); however, there was scant reporting of antibiotic resistance - the one study that did assess this found no increase.In two studies of children with cystic fibrosis receiving ciprofloxacin prophylaxis, there was no significant difference in Pseudomonas infections (RR 0.76, 0.44 to 1.31, I(2) statistic = 0%, P value = 0.33). In two studies assessing the benefit of azithromycin prophylaxis, there was a significant reduction in the frequency of pulmonary exacerbations (RR 0.60, 95% CI 0.48 to 0.76, I(2) statistic = 0%, P value < 0.0001). The effect of antibiotic prophylaxis on growth in children with cystic fibrosis was inconsistent across the studies. There was an increased risk of emergence of pathogenic strains with either azithromycin or ciprofloxacin prophylaxis in two studies reporting this outcome. There was no significant difference in the quality of life (one study). In three studies, there was no significant increase in the frequency of adverse events with prophylaxis with azithromycin (two studies) or ciprofloxacin (one study). There was no evidence of increased antibiotic resistance in two studies.In the one study of children with sickle cell disease, a significantly lesser proportion of children with pneumococcal septicaemia was reported with penicillin V prophylaxis (P value = 0.0025).In the one study of children with cancer there was a significant decrease in Pneumocystis carinii pneumonia with trimethoprim-sulfamethoxazole prophylaxis (RR 0.03, 95% CI 0.00 to 0.47, P value < 0.01). There was no significant increase in the frequency of adverse events with antibiotic prophylaxis.In low birth weight children with underlying respiratory disorders, there was no significant difference in the proportion of children with pulmonary infection with vancomycin prophylaxis (P value = 0.18).No included studies reported time off school or carer time off work.

AUTHORS' CONCLUSIONS

There is inconclusive evidence that antibiotic prophylaxis in certain groups of high-risk children can reduce pneumonia, exacerbations, hospital admission and mortality in certain conditions. However, limitations in the evidence base mean more clinical trials assessing the effectiveness of antibiotics for preventing LRTIs in children at high risk should be conducted. Specifically, clinical trials assessing the effectiveness of antibiotics for preventing LRTIs in congenital heart disease, metabolic disease, endocrine and renal disorders, neurological disease or prematurity should be a priority.

Air pollution interacts with past episodes of bronchiolitis in the development of asthma

BACKGROUND

Exposure to ambient air pollution and bronchiolitis are risk factors for asthma. The aim of this study was to investigate the effect of air pollution on the development of asthma in children with past episodes of bronchiolitis.

METHODS

A prospective 2-year follow-up survey consisting of parental responses to the International Study of Asthma and Allergies in Childhood (ISAAC) questionnaire, and allergy evaluations were conducted in 1743 children with a mean age of 6.8 years. Recent 5-year exposure to air pollution was estimated using a geographic information system.

RESULTS

Higher exposure to ozone was associated with airway hyper-responsiveness (PC20  ≤ 16 mg/ml) at enrollment (odds ratio [OR] = 1.60, 95% CI [confidence interval] = 1.13-2.27) and with new episodes of wheezing during the 2-year period (OR = 1.92, 95% CI = 0.96-3.83). Past episodes of bronchiolitis were associated with both current wheezing and physician-diagnosed asthma. When the two factors were combined, the prevalence of bronchial hyper-reactivity (OR = 2.96, 95% CI = 1.41-6.24) and new wheezing (OR = 4.17, 95% CI = 0.89-19.66) as well as current wheezing and physician-diagnosed asthma was even greater (P for trend <0.05 for all). In children with both risk factors, lung function was significantly decreased, with atopic children being particularly vulnerable.

CONCLUSION

In children, the interaction between air pollution and past episodes of bronchiolitis resulted in a greater prevalence of asthma and pointed to an association with bronchial hyper-reactivity and decreased lung function. These results suggest mechanisms underlying the development of asthma.

Causes and risk factors for infant mortality in Nunavut, Canada 1999-2011

BACKGROUND

The northern territory Nunavut has Canada's largest jurisdictional land mass with 33,322 inhabitants, of which 85% self-identify as Inuit. Nunavut has rates of infant mortality, postneonatal mortality and hospitalisation of infants for respiratory infections that greatly exceed those for the rest of Canada. The infant mortality rate in Nunavut is 3 times the national average, and twice that of the neighbouring territory, the Northwest Territories. Nunavut has the largest Inuit population in Canada, a population which has been identified as having high rates of Sudden Infant Death Syndrome (SIDS) and infant deaths due to infections.

METHODS

To determine the causes and potential risk factors of infant mortality in Nunavut, we reviewed all infant deaths (<1 yr) documented by the Nunavut Chief Coroner's Office and the Nunavut Bureau of Statistics (n=117; 1999-2011). Rates were compared to published data for Canada.

RESULTS

Sudden death in infancy (SIDS/SUDI; 48%) and infection (21%) were the leading causes of infant death, with rates significantly higher than for Canada (2003-2007). Of SIDS/SUDI cases with information on sleep position (n=42) and bed-sharing (n=47), 29 (69%) were sleeping non-supine and 33 (70%) were bed-sharing. Of those bed-sharing, 23 (70%) had two or more additional risk factors present, usually non-supine sleep position. CPT1A P479L homozygosity, which has been previously associated with infant mortality in Alaska Native and British Columbia First Nations populations, was associated with unexpected infant death (SIDS/SUDI, infection) throughout Nunavut (OR:3.43, 95% CI:1.30-11.47).

CONCLUSION

Unexpected infant deaths comprise the majority of infant deaths in Nunavut. Although the CPT1A P479L variant was associated with unexpected infant death in Nunavut as a whole, the association was less apparent when population stratification was considered. Strategies to promote safe sleep practices and further understand other potential risk factors for infant mortality (P479L variant, respiratory illness) are underway with local partners.