Protein misfolding and clearance in the pathogenesis of a new infantile onset ataxia caused by mutations in PRDX3.

Peroxiredoxin 3 (PRDX3) encodes a mitochondrial antioxidant protein, which is essential for the control of reactive oxygen species homeostasis. So far, PRDX3 mutations are involved in mild-to-moderate progressive juvenile onset cerebellar ataxia. We aimed to unravel the molecular bases underlying the disease in an infant suffering from cerebellar ataxia that started at 19 months old and presented severe cerebellar atrophy and peripheral neuropathy early in the course of disease. By whole exome sequencing, we identified a novel homozygous mutation, PRDX3 p.D163E, which impaired the mitochondrial ROS defense system. In mouse primary cortical neurons, the exogenous expression of PRDX3 p.D163E was reduced and triggered alterations in neurite morphology and in mitochondria. Mitochondrial computational parameters showed that p.D163E led to serious mitochondrial alterations. In transfected HeLa cells expressing the mutation, mitochondria accumulation was detected by correlative light electron microscopy. Mitochondrial morphology showed severe changes, including extremely damaged outer and inner membranes with a notable cristae disorganization. Moreover, spherical structures compatible with lipid droplets were identified, which can be associated with a generalized response to stress and can be involved in the removal of unfolded proteins. In the patient's fibroblasts, PRDX3 expression was nearly absent. The biochemical analysis suggested that the mutation p.D163E would result in an unstable structure tending to form aggregates that trigger unfolded protein responses via mitochondria and endoplasmic reticulum. Altogether, our findings broaden the clinical spectrum of the recently described PRDX3-associated neurodegeneration and provide new insight into the pathological mechanisms underlying this new form of cerebellar ataxia.

Using a theoretically informed process evaluation alongside a trial to improve oral health for care home residents.

BACKGROUND: Poor oral health is common among older adults residing in care homes impacting their diet, quality of life, self-esteem, general health and well-being. The care home setting is complex and many factors may affect the successful implementation of oral care interventions. Exploring these factors and their embedded context is key to understanding how and why interventions may or may not be successfully implemented within their intended setting. OBJECTIVES: This methodology paper describes the approach to a theoretically informed process evaluation alongside a pragmatic randomised controlled trial, so as to understand contextual factors, how the intervention was implemented and important elements that may influence the pathways to impact. MATERIALS AND METHODS: SENIOR is a pragmatic randomised controlled trial designed to improve the oral health of care home residents in the United Kingdom. The trial uses a complex intervention to promote and provide oral care for residents, including education and training for staff. RESULTS: An embedded, theoretically informed process evaluation, drawing on the PAHRIS framework and utilising a qualitative approach, will help to understand the important contextual factors within the care home that influence both the trial processes and the implementation of the intervention. CONCLUSION: Utilising an implementation framework as the basis for a theoretically informed process evaluation provides an approach that specifically focuses on the contextual factors that may influence and shape the pathways to impact a given complex intervention a priori, while also providing an understanding of how and why an intervention may be effective. This contrasts with the more common post hoc approach that only focuses on implementation after the empirical results have emerged.

Setting the context for a complex dental intervention of role substitution in care homes: Initial process evaluation findings.

OBJECTIVES: SENIOR (uSing rolE-substitutioN In care homes to improve oRal health) is a randomised controlled trial designed to determine whether role substitution could improve oral health for this population. A parallel process evaluation was undertaken to understand context. This paper reports on the first phase of the process evaluation. BACKGROUND: The oral health and quality-of-life of older adults residing in care homes is poorer than those in the community. Oral health care provision is often unavailable and a concern and challenge for managers. The use of Dental Therapists and Dental Nurses rather than dentists could potentially meet these needs. MATERIALS AND METHODS: Semi-structured interviews were conducted with 21 key stakeholders who either worked or had experience of dependent care settings. Questions were theoretically informed by the: Promoting Action on Research Implementation in Health Services (PAHRIS) framework. The focus was on contextual factors that could influence adoption in practice and the pathway-to-impact. Interviews were fully transcribed and analysed thematically. RESULTS: Three themes (receptive context, culture, and leadership) and 11 codes were generated. Data show the complexity of the setting and contextual factors that may work as barriers and facilitators to intervention delivery. Managers are aware of the issues regarding oral health and seek to provide best care, but face many challenges including staff turnover, time pressures, competing needs, access to services, and financial constraints. Dental professionals recognise the need for improvement and view role substitution as a viable alternative to current practice. CONCLUSION: Although role substitution could potentially meet the needs of this population, an in-depth understanding of contextual factors appeared important in understanding intervention delivery and implementation.

Addressing social barriers and closing the gender knowledge gap: exposure to road shows is associated with more knowledge and more positive beliefs, attitudes and social norms regarding exclusive breastfeeding in rural Zimbabwe.

Exclusive breastfeeding (EBF) is rarely practiced despite its significant child survival benefits. A key constraint to increasing EBF rates in Zimbabwe and most of the developing world is that key decision makers (fathers/partners and other family members) are often poorly informed about EBF and do not attend antenatal clinics where health information is routinely provided. Informed by formative research, a district-wide campaign was conducted in rural Zimbabwe to encourage EBF and expressing and heat treating (EHT) breast milk as a means to maintain EBF. The campaign combined traditional strategies of education, counselling and outreach through health service delivery with a novel road show 'edutainment' intervention to reach men and other community members. A post campaign evaluation measured the association of road show exposure with 20 knowledge items and summative scores of social norms, beliefs and attitudes obtained through exploratory factor analysis. In adjusted models, road show exposure was associated with correct EBF knowledge (ß=1.0, 0.001), EHT knowledge (ß=1.3, P<0.001) and greater perceived benefits of condom use during pregnancy and breastfeeding (ß=0.5, P<0.001), and more positive EBF social norms (ß=0.6, P<0.001), EBF beliefs and attitudes (ß=1.0, P<0.001) and attitudes towards condom use during breastfeeding (ß=0.6, P<0.001). Road show exposure was more strongly associated with EBF knowledge among men (P-value for gender×exposure group interaction=0.03), suggesting that it also closed the knowledge gap between men and women. Longitudinal studies will determine whether road shows were associated with changes in EBF practices.

Inhaled Corticosteroids Alone and in Combination With Long-Acting ß2 Receptor Agonists to Treat Reduced Lung Function in Preterm-Born Children: A Randomized Clinical Trial.

Importance: Decreases in future lung function are a hallmark of preterm birth, but studies for management of decreased lung function are limited. Objective: To determine whether 12 weeks of treatment with inhaled corticosteroids (ICS) alone or in combination with long-acting ß2 agonists (LABA) improves spirometry and exercise capacity in school-aged preterm-born children who had percent predicted forced expiratory volume in 1 second (%FEV1) less than or equal to 85% compared with inhaled placebo treatment. Design, Setting, and Participants: A double-blind, randomized, placebo-controlled trial was conducted to evaluate ICS and ICS/LABA against placebo. Preterm-born children (age, 7-12 years; gestation ≤34 weeks at birth) who did not have clinically significant congenital, cardiopulmonary, or neurodevelopmental abnormalities underwent spirometry, exercise testing, and measurement of fractional exhaled nitric oxide before and after treatment. A total of 144 preterm-born children at the Children's Hospital for Wales in Cardiff, UK, were identified and enrolled between July 1, 2017, and August 31, 2019. Interventions: Each child was randomized to 1 of 3 cohorts: fluticasone propionate, 50 µg, with placebo; fluticasone propionate, 50 µg, with salmeterol, 25 µg; or placebo inhalers, all given as 2 puffs twice daily for 12 weeks. Children receiving preexisting ICS treatment underwent washout prior to randomization to ICS or ICS/LABA. Main Outcomes and Measures: The primary outcome was between-group differences assessed by adjusted pretreatment and posttreatment differences of %FEV1 using analysis of covariance. Intention-to-treat analysis was conducted. Results: Of 144 preterm-born children who were identified with %FEV1 less than or equal to 85%, 53 were randomized. Treatment allocation was 20 children receiving ICS (including 5 with prerandomization ICS), 19 children receiving ICS/LABA (including 4 with prerandomization ICS), and 14 children receiving placebo. The mean (SD) age of children was 10.8 (1.2) years, and 29 of the randomized children (55%) were female. The posttreatment %FEV1 was adjusted for sex, gestation, bronchopulmonary dysplasia, intrauterine growth restriction, pretreatment corticosteroid status, treatment group, and pretreatment values. Posttreatment adjusted means for %FEV1, using analysis of covariance, were 7.7% (95% CI, -0.27% to 15.72%; P = .16) higher in the ICS group and 14.1% (95% CI, 7.3% to 21.0%; P = .002) higher in the ICS/LABA group compared with the placebo group. Active treatment decreased the fractional exhaled nitric oxide and improved postexercise bronchodilator response but did not improve exercise capacity. One child developed cough when starting inhaler treatment; no other adverse events reported during the trial could be attributed to the inhaler treatment. Conclusions and Relevance: The results of this randomized clinical trial suggest that combined ICS/LABA treatment is beneficial for prematurity-associated lung disease in children. Trial Registration: EudraCT number: 2015-003712-20.

uSing rolE-substitutioN In care homes to improve ORal health (SENIOR): a study protocol.

BACKGROUND: Dental service provision in the care home sector is poor, with little emphasis on prevention. Emerging evidence suggests that the use of Dental Care Professionals (dental therapists and dental nurses) as an alternative to dentists has the potential to improve preventive advice, the provision of care and access to services within care homes. However, robust empirical evidence from definitive trials on how to successfully implement and sustain these interventions within care homes is currently lacking. The aim of the study is to determine whether Dental Care Professionals could reduce plaque levels of dentate older adults (65 + years) residing in care homes. METHODS: This protocol describes a two-arm cluster-randomised controlled trial that will be undertaken in care homes across Wales, Northern Ireland and England. In the intervention arm, the dental therapists will visit the care homes every 6 months to assess and then treat eligible residents, where necessary. All treatment will be conducted within their Scope of Practice. Dental nurses will visit the care homes every month for the first 3 months and then three-monthly afterwards to promulgate advice to improve the day-to-day prevention offered to residents by carers. The control arm will be 'treatment as usual'. Eligible care homes (n = 40) will be randomised based on a 1:1 ratio (20 intervention and 20 control), with an average of seven residents recruited in each home resulting in an estimated sample of 280. Assessments will be undertaken at baseline, 6 months and 12 months and will include a dental examination and quality of life questionnaires. Care home staff will collect weekly information on the residents' oral health (e.g. episodes of pain and unscheduled care). The primary outcome will be a binary classification of the mean reduction in Silness-Löe Plaque Index at 6 months. A parallel process evaluation will be undertaken to explore the intervention's acceptability and how it could be embedded in standard practice (described in a separate paper), whilst a cost-effectiveness analysis will examine the potential long-term costs and benefits of the intervention. DISCUSSION: This trial will provide evidence on how to successfully implement and sustain a Dental Care Professional-led intervention within care homes to promote access and prevention. TRIAL REGISTRATION: ISRCTN16332897 . Registered on 3 December 2021.

Improving the oral health of older people in care homes (TOPIC): a protocol for a feasibility study.

BACKGROUND: Evidence for interventions promoting oral health amongst care home residents is weak. The National Institute for Health and Care Excellence (NICE) guideline NG48 aims to maintain and improve the oral health of care home residents. A co-design process that worked with residents and care home staff to understand how the NG48 guideline could be best implemented in practice has been undertaken to refine a complex intervention. The aim of this study is to assess the feasibility of the intervention to inform a future larger scale definitive trial. METHODS: This is a protocol for a pragmatic cluster randomised controlled trial with a 12-month follow-up that will be undertaken in 12 care homes across two sites (six in London, six in Northern Ireland). Care homes randomised to the intervention arm (n = 6) will receive the complex intervention based on the NG48 guideline, whilst care homes randomised to the control arm (n = 6) will continue with routine practice. The intervention will include a training package for care home staff to promote knowledge and skills in oral health promotion, the use of the Oral Health Assessment Tool on residents by trained care home staff, and a 'support worker assisted' daily tooth-brushing regime with toothpaste containing 1500 ppm fluoride. An average of ten residents, aged 65 years or over who have at least one natural tooth, will be recruited in each care home resulting in a recruited sample of 120 participants. Assessments will be undertaken at baseline, 6 months and 12 months, and will include a dental examination and questionnaires on general health and oral health administered by a research assistant. A parallel process evaluation involving semi-structured interviews will be undertaken to explore how the intervention could be embedded in standard practice. Rates of recruitment and retention, and intervention fidelity will also be recorded. A cost-consequence model will determine the relevance of different outcome measures in the decision-making context. DISCUSSION: The study will provide valuable information for trialists, policymakers, clinicians and care home staff on the feasibility and associated costs of oral health promotion in UK care homes. TRIAL REGISTRATION: ISRCTN10276613. Registered on 17th April 2020. http://www.isrctn.com/ISRCTN10276613 .

Heat treatment of expressed breast milk is a feasible option for feeding HIV-exposed, uninfected children after 6 months of age in rural Zimbabwe.

In the context of a prevention of mother to child transmission of HIV program promoting exclusive breast-feeding (EBF) to 6 mo and offering HIV-PCR testing at approximately 6 mo, we ascertained the feasibility of expressing and heat-treating (EHT) all breast milk fed to HIV-exposed, uninfected infants following 6 mo of EBF. Twenty mother-baby pairs were enrolled from a hospital in rural Zimbabwe. Research nurses provided lactation, EHT, and complementary feeding counseling through 21 home visits conducted over an 8-wk period and collected quantitative and qualitative data on the mothers' EHT experiences, children's diets, and anthropometric measurements. Mothers kept daily logs of EHT volumes and direct breast-feeding episodes. Mothers successfully initiated and sustained EHT for 4.5 mo (range, 1-11 mo), feeding 426 +/- 227 mL/d (mean +/- SD). By wk 2 of follow-up, children were receiving EHT and Nutributter-enriched complementary foods that satisfied 100% of their energy requirements. During the 8-wk follow-up period, no growth faltering was experienced [changes in weight-for-age, weight-for-length, and length-for-age Z scores = +0.03 +/- 0.50; +0.77 +/- 1.59; and +0.02 +/- 0.85 (mean +/- SD), respectively]. Stigma was not a major deterrent, likely due to a social marketing campaign for EBF that promoted EHT as a practice to sustain breast-feeding for all women. This study provides evidence that resource-poor rural women can initiate and sustain EHT given family and health systems support. EHT provides a strategy for improving the diets of HIV-exposed but uninfected children after direct breast-feeding has ceased.

Impaired proteasome activity and neurodegeneration with brain iron accumulation in FBXO7 defect.

FBXO7 is implicated in the ubiquitin-proteasome system and parkin-mediated mitophagy. FBXO7defects cause a levodopa-responsive parkinsonian-pyramidal syndrome(PPS). METHODS: We investigated the disease molecular bases in a child with PPS and brain iron accumulation. RESULTS: A novel homozygous c.368C>G (p.S123*) FBXO7 mutation was identified in a child with spastic paraplegia, epilepsy, cerebellar degeneration, levodopa nonresponsive parkinsonism, and brain iron deposition. Patient's fibroblasts assays demonstrated an absence of FBXO7 RNA expression leading to impaired proteasome degradation and accumulation of poly-ubiquitinated proteins. CONCLUSION: This novel FBXO7 phenotype associated with impaired proteasome activity overlaps with neurodegeneration with brain iron accumulation disorders.

HIV-positive poor women may stop breast-feeding early to protect their infants from HIV infection although available replacement diets are grossly inadequate.

Little is known about mothers' perspectives and experiences of early breast-feeding cessation as a strategy to reduce postnatal HIV transmission in rural, resource-constrained settings. We conducted in-depth interviews (IDI) with 15 HIV-positive breast-feeding mothers of infants aged 3-5 mo about their plans for feeding their infants after age 6 mo. We also conducted IDI with 12 HIV-positive mothers who intended to stop breast-feeding after receiving their infant's HIV-PCR negative test result at age 6 mo. Twenty-four-hour dietary recalls were conducted with the same 12 mothers and 16 HIV-negative or status unknown mothers who were breast-feeding their 6- to 9-mo-old infants. Of the 12 mothers who intended to stop breast-feeding, 11 did so by 9 mo. Median energy intake (percent requirement) was 1382 kJ (54%) among weaned infants compared with 2234 kJ (87%) among breast-feeding infants. Median intakes were <67% of the recommended levels for 9 and 7 of the 12 micronutrients assessed for weaned and breast-feeding infants, respectively. Factors facilitating early breast-feeding cessation were mothers' knowledge about HIV transmission, family support, and disclosure of their HIV status; food unavailability was the primary barrier. HIV-positive mothers in resource-constrained settings may be so motivated to protect their child from HIV that they stop breast-feeding early even when they cannot provide an adequate replacement diet. As reflected in the new World Health Organization guidance, HIV-positive mothers should continue breastfeeding their infants beyond 6 mo if replacement feeding is still not acceptable, feasible, affordable, sustainable, and safe.

Lessons learnt from a discontinued randomised controlled trial: adalimumab injection compared with placebo for patients receiving physiotherapy treatment for sciatica (Subcutaneous Injection of Adalimumab Trial compared with Control: SCIATiC).

BACKGROUND: Adalimumab, a biological treatment targeting tumour necrosis factor α, might be useful in sciatica. This paper describes the challenges faced when developing a new treatment pathway for a randomised controlled trial of adalimumab for people with sciatica, as well as the reasons why the trial discussed was stopped early. METHODS: A pragmatic, parallel group, randomised controlled trial with blinded (masked) participants, clinicians, outcome assessment and statistical analysis was conducted in six UK sites. Participants were identified and recruited from general practices, musculoskeletal services and outpatient physiotherapy clinics. They were adults with persistent symptoms of sciatica of 1 to 6 months' duration with moderate to high level of disability. Eligibility was assessed by research physiotherapists according to clinical criteria, and participants were randomised to receive two doses of adalimumab (80 mg then 40 mg 2 weeks later) or saline placebo subcutaneous injections in the posterior lateral thigh. Both groups were referred for a course of physiotherapy. Outcomes were measured at baseline, 6-week, 6-month and 12-month follow-up. The main outcome measure was disability measured using the Oswestry Disability Index. The planned sample size was 332, with the first 50 in an internal pilot phase. RESULTS: The internal pilot phase was discontinued after 10 months from opening owing to low recruitment (two of the six sites active, eight participants recruited). There were several challenges: contractual delays; one site did not complete contract negotiations, and two sites signed contracts shortly before trial closure; site withdrawal owing to patient safety concerns; difficulties obtaining excess treatment costs; and in the two sites that did recruit, recruitment was slower than planned because of operational issues and low uptake by potential participants. CONCLUSIONS: Improved patient care requires robust clinical research within contexts in which treatments can realistically be provided. Step changes in treatment, such as the introduction of biologic treatments for severe sciatica, raise complex issues that can delay trial initiation and retard recruitment. Additional preparatory work might be required before testing novel treatments. A randomised controlled trial of tumour necrosis factor-α blockade is still needed to determine its cost-effectiveness in severe sciatica. TRIAL REGISTRATION: Current Controlled Trials, ISRCTN14569274 . Registered on 15 December 2014.

Subcutaneous Injection of Adalimumab Trial compared with Control (SCIATiC): a randomised controlled trial of adalimumab injection compared with placebo for patients receiving physiotherapy treatment for sciatica.

BACKGROUND: Biological treatments such as adalimumab (Humira®; AbbVie Ltd, Maidenhead, UK) are antibodies targeting tumour necrosis factor alpha, released from ruptured intervertebral discs, which might be useful in sciatica. Recent systematic reviews concluded that they might be effective, but that a definitive randomised controlled trial was needed. Usual care in the NHS typically includes a physiotherapy intervention. OBJECTIVES: To test whether or not injections of adalimumab plus physiotherapy are more clinically effective and cost-effective than injections of saline plus physiotherapy for patients with sciatica. DESIGN: Pragmatic, parallel-group, randomised controlled trial with blinded participants and clinicians, and an outcome assessment and statistical analysis with concurrent economic evaluation and internal pilot. SETTING: Participants were referred from primary care and musculoskeletal services to outpatient physiotherapy clinics. PARTICIPANTS: Adults with persistent symptoms of sciatica of 1-6 months' duration and with moderate to high levels of disability. Eligibility was assessed by research physiotherapists according to clinical criteria for diagnosing sciatica. INTERVENTIONS: After a second eligibility check, trial participants were randomised to receive two doses of adalimumab (80 mg and then 40 mg 2 weeks later) or saline injections. Both groups were referred for a course of physiotherapy. MAIN OUTCOME MEASURES: Outcomes were measured at the start, and after 6 weeks' and 6 months' follow-up. The main outcome measure was the Oswestry Disability Index (ODI). Other outcomes: leg pain version of the Roland-Morris Disability Questionnaire, Sciatica Bothersomeness Index, EuroQol-5 Dimensions, 5-level version, Hospital Anxiety and Depression Scale, resource use, risk of persistent disabling pain, pain trajectory based on a single question, Pain Self-Efficacy Questionnaire, Tampa Scale of Kinesiophobia and adverse effects. SAMPLE SIZE: To detect an effect size of 0.4 with 90% power, a 5% significance level for a two-tailed t-test and 80% retention rate, 332 participants would have needed to be recruited. ANALYSIS PLAN: The primary effectiveness analysis would have been linear mixed models for repeated measures to measure the effects of time and group allocation. An internal pilot study would have involved the first 50 participants recruited across all centres. The primary economic analysis would have been a cost-utility analysis. RESULTS: The internal pilot study was discontinued as a result of low recruitment after eight participants were recruited from two out of six sites. One site withdrew from the study before recruitment started, one site did not complete contract negotiations and two sites signed contracts shortly before trial closure. In the two sites that did recruit participants, recruitment was slow. This was partly because of operational issues, but also because of a low rate of uptake from potential participants. LIMITATIONS: Although large numbers of invitations were sent to potential participants, identified by retrospective searches of general practitioner (GP) records, there was a low rate of uptake. Two sites planned to recruit participants during GP consultations but opened too late to recruit any participants. CONCLUSION: The main failure was attributable to problems with contracts. Because of this we were not able to complete the internal pilot or to test all of the different methods for primary care recruitment we had planned. A trial of biological therapy in patients with sciatica still needs to be done, but would require a clearer contracting process, qualitative research to ensure that patients would be willing to participate, and simpler recruitment methods. TRIAL REGISTRATION: Current Controlled Trials ISRCTN14569274. FUNDING: This project was funded by the National Institute for Health Research (NIHR) Health Technology Assessment programme and will be published in full in Health Technology Assessment; Vol. 21, No. 60. See the NIHR Journals Library website for further project information.

Identifying eating disorders.

While most nurses are familiar with anorexia and bulimia, how many nurses have heard of compulsive overeating, also known as binge eating? This is not a new condition but the medical profession has been very slow to recognize it as a problem, let alone as an eating disorder. This article looks at the different types of eating disorders, their differences, how to identify sufferers and where to refer them. Identifying patients with eating disorders is a very hard task since sufferers have learned the art of secrecy, denial and deception.

Risk factors for hospitalization and infection in Canadian Inuit infants over the first year of life--a pilot study.

OBJECTIVES: Inuit infants experience higher mortality and poorer health than other Canadian infants, and suffer disproportionately from bacterial and viral infections. A wide range of inter-related factors affect their health and susceptibility to infection. The objective of the study was to describe hospitalization and morbidity patterns in a cohort of 46 healthy Inuit infants from Iqaluit, Nunavut, over their first year of life. STUDY DESIGN: Risk factors for hospitalization and infections were assessed using multiple linear regression. RESULTS: Infants experienced an average of four respiratory tract infections (RTIs) annually, which accounted for half of the hospitalizations in the cohort. Some interesting trends were evident from the assessment of risk factors using multiple linear regression. Adoption was associated with adverse health effects in addition to those that would be expected due to lack of breast-freeding alone; among infants who were not breast-fed, adopted infants had three more RTIs per year than non-adopted infants. CONCLUSION: The results of this pilot study provide support for undertaking larger epidemiological studies in order to clarify the role of these risk factors, so that future preventive efforts can be informed and effective.

An overview of factors influencing the health of Canadian Inuit infants.

BACKGROUND: Inuit infants throughout the Arctic experience higher mortality and poorer health than their non-Inuit counterparts, and suffer disproportionately from bacterial and viral infections. STUDY DESIGN: This review examines the health status of these infants, with a focus on Canadian Inuit communities and reference to other circumpolar regions, as appropriate. It is based on a Medline search (1965 to present), special analyses of the 1996 Canadian Census and various national surveys, and selected government reports and documents. RESULTS: A wide range of inter-related factors affect the health of Inuit infants: their demographic, social, economic and physical environment, as well as personal health practices and the availability of high quality, culturally appropriate health services. Some of these factors may influence the susceptibility of Inuit infants to infection. Smoking is highly prevalent in Inuit communities, and its indisputable negative effects on health, including increased risk of respiratory tract infection in infants, represent an urgent public health challenge. CONCLUSION: Locally driven, focused and methodologically sound epidemiological research that addresses key gaps in knowledge could lead to more appropriate and effective preventive strategies to improve health in northern communities.