Health effects of indoor nitrogen dioxide

Rationale: Exposure to indoor NO2 has been implicated as a cause of respiratory symptoms suggestive of asthma but evidence has been inconsistent. Objective: To review the existing evidence and examine the effects of indoor NO2 in adult asthma-related symptoms using data from an adult multi-centre cohort (ECRHS) followed up for 20 years. Methods: Studies on respiratory health and indoor NO2 were systematically reviewed and meta-analyses performed. Cross-sectional analyses within a sub-set of ECRHS participants with indoor NO2 measurements were conducted to assess the associations of asthma severity and wheeze prevalence with NO2. A regression model was developed to predict indoor NO2 for a larger ECRHS sample without indoor NO2 measurements. GEE analyses were conducted to examine the long-term effects of gas cooking and modelled indoor NO2 on wheeze and asthma score. To investigate the effect of gas-generating NO2 peaks on asthma exacerbation a panel study was also piloted using a new-to-market portable NO2 sensor. Main results: The systematic review identified 50 studies, mainly in children. Results of meta-analyses suggested a significant association between 12-month period prevalence of wheeze and indoor NO2. Within ECRHS prevalence of wheeze but not asthma severity was associated with measured indoor NO2. Long-term associations of asthma-related symptoms with predicted indoor NO2 exposure but not gas cooking were significant. Interpreting this is difficult as the latter analyses (gas cooking) included a larger number of centres and some heterogeneity across centres was observed in the analysis on asthma score. Gas appliances, outdoor NO2, monthly temperature and country were the main predictors of indoor NO2. Evaluation of the pilot study recommends better recruitment strategies and independent calibration of NO2 sensor. Conclusions: There is some evidence for a link between indoor NO2 and asthma-related symptoms. Health risks may be small but are applied to a substantial proportion of the population.Open Acces

Incidence and associations of hospital delirium diagnoses in 85979 people with severe mental illness: a data linkage study

INTRODUCTION: Delirium is an acute neuro-psychiatric disturbance precipitated by a range of physical stressors, with high morbidity and mortality. Little is known about its relationship with severe mental illness (SMI). METHODS: We conducted a retrospective cohort study using linked data analyses of the UK Clinical Practice Research Datalink (CPRD) and Hospital Episodes Statistics (HES) databases. We ascertained yearly hospital delirium incidence from 2000 - 2017 and used logistic regression to identify associations with delirium diagnosis in a population with severe mental illness. RESULTS: The cohort included 249,047 people with severe mental illness with median follow-up time in CPRD of 6.4 years. 85,979 patients were eligible for linkage to HES. Delirium incidence increased from 0.04 (95% CI 0.02 - 0.07) delirium associated admissions per 100 person-years in 2000 to 1.05 (95% CI 0.93 - 1.17) per 100 person-years in 2017, increasing most notably from 2010 onwards. Delirium was associated with older age at study entry (OR 1.05 per year, 95% CI 1.05-1.06), SMI diagnosis of bipolar affective disorder (OR 1.66, 95% CI 1.44 - 1.93) or other psychosis (OR 1.56, 95% CI 1.35 - 1.80) relative to schizophrenia, and more physical comorbidities (OR 1.08 per additional comorbidity of the Charlson Comorbidity Index, 95% CI 1.02 - 1.14). Patients with delirium received more antipsychotic medication during follow-up (1-2 antipsychotics OR 1.65, 95% CI 1.44 - 1.90; >2 antipsychotics OR 2.49, 95% CI 2.12 - 2.92). CONCLUSIONS: The incidence of recorded delirium diagnoses in people with severe mental illness has increased in recent years. Older people prescribed more antipsychotics and with more comorbidities have a higher incidence. Linked electronic health records are feasible for exploring hospital diagnoses such as delirium in SMI

Factors predicting amoxicillin prescribing in primary care among children: a cohort study

Background: Antibiotic prescribing during childhood contributes to antimicrobial resistance, which is a major public health concern. Antibiotics are most commonly prescribed to children for respiratory tract infections (RTI). / Aim: To identify factors associated with amoxicillin prescribing and RTI consultation attendance in primary care in young children. / Design and Setting: Cohort study in Bradford with data from pregnancy to age 24-months collected between 2007-2013, linked to electronic primary care and air pollution data. / Methods: We calculated amoxicillin prescribing rates/1,000 child-years, and fitted mixed-effects logistic regression models, with general practice (GP) surgery as the random effect, to establish risk factors for amoxicillin prescribing and RTI consultation during the first two years. / Results: Among 2,493 children, the amoxicillin prescribing rate was 710/1,000 child-years during the first year (95% CI: 677-744) and 780/1,000 (745-816) during the second year. Odds of amoxicillin prescribing during year one were higher for infants who were male (adjusted OR 1.4 (1.1-1.6)), socio-economically deprived (1.4 (1.0-1.9)), and with a Pakistani ethnic background (1.4 (1.1-1.9)). Odds of amoxicillin prescribing during the second year were higher for infants with a Pakistani ethnic background (1.5 (1.1-2.0)/1.6 (1.2-2.0)) and pre-/early-term infants (1.2 (1.0-1.5)). Additional risk factors included caesarean delivery, congenital anomalies, household overcrowding, birth season, and formal childcare attendance. GP surgery-level variation explained 7-9% of variation in amoxicillin prescribing. / Conclusions: Socio-economic status and ethnic background are strongly associated with amoxicillin prescribing and RTI consultations during childhood. Interventions reducing RTI spread in household and childcare settings may reduce antibiotic prescribing in primary care

SARS-CoV-2 tests, confirmed infections and COVID-19 related hospital admissions in children and young people:birth cohort study

Background There have been no population-based studies of SARS-CoV-2 testing, PCR-confirmed infections and COVID-19-related hospital admissions across the full paediatric age range. We examine the epidemiology of SARS-CoV-2 in children and young people (CYP) aged <23 years. Methods We used a birth cohort of all children born in Scotland since 1997, constructed via linkage between vital statistics, hospital records and SARS-CoV-2 surveillance data. We calculated risks of tests and PCR-confirmed infections per 1000 CYP-years between August and December 2020, and COVID-19-related hospital admissions per 100 000 CYP-years between February and December 2020. We used Poisson and Cox proportional hazards regression models to determine risk factors. Results Among the 1 226 855 CYP in the cohort, there were 378 402 tests (a rate of 770.8/1000 CYP-years (95% CI 768.4 to 773.3)), 19 005 PCR-confirmed infections (179.4/1000 CYP-years (176.9 to 182.0)) and 346 admissions (29.4/100 000 CYP-years (26.3 to 32.8)). Infants had the highest COVID-19-related admission rates. The presence of chronic conditions, particularly multiple types of conditions, was strongly associated with COVID-19-related admissions across all ages. Overall, 49% of admitted CYP had at least one chronic condition recorded. Conclusions Infants and CYP with chronic conditions are at highest risk of admission with COVID-19. Half of admitted CYP had chronic conditions. Studies examining COVID-19 vaccine effectiveness among children with chronic conditions and whether maternal vaccine during pregnancy prevents COVID-19 admissions in infants are urgently needed

Factors predicting amoxicillin prescribing in primary care among children: a cohort study

Background: Antibiotic prescribing during childhood contributes to antimicrobial resistance, which is a major public health concern. Antibiotics are most commonly prescribed to children for respiratory tract infections (RTI). Aim: To identify factors associated with amoxicillin prescribing and RTI consultation attendance in primary care in young children. Design and Setting: Cohort study in Bradford with data from pregnancy to age 24-months collected between 2007-2013, linked to electronic primary care and air pollution data. Methods: We calculated amoxicillin prescribing rates/1,000 child-years, and fitted mixed-effects logistic regression models, with general practice (GP) surgery as the random effect, to establish risk factors for amoxicillin prescribing and RTI consultation during the first two years. Results: Among 2,493 children, the amoxicillin prescribing rate was 710/1,000 child-years during the first year (95% CI: 677-744) and 780/1,000 (745-816) during the second year. Odds of amoxicillin prescribing during year one were higher for infants who were male (adjusted OR 1.4 (1.1-1.6)), socio-economically deprived (1.4 (1.0-1.9)), and with a Pakistani ethnic background (1.4 (1.1-1.9)). Odds of amoxicillin prescribing during the second year were higher for infants with a Pakistani ethnic background (1.5 (1.1-2.0)/1.6 (1.2-2.0)) and pre-/early-term infants (1.2 (1.0-1.5)). Additional risk factors included caesarean delivery, congenital anomalies, household overcrowding, birth season, and formal childcare attendance. GP surgery-level variation explained 7-9% of variation in amoxicillin prescribing. Conclusions: Socio-economic status and ethnic background are strongly associated with amoxicillin prescribing and RTI consultations during childhood. Interventions reducing RTI spread in household and childcare settings may reduce antibiotic prescribing in primary care.</jats:p

Traffic-related pollution and asthma prevalence in children. Quantification of associations with nitrogen dioxide.

Ambient nitrogen dioxide is a widely available measure of traffic-related air pollution and is inconsistently associated with the prevalence of asthma symptoms in children. The use of this relationship to evaluate the health impact of policies affecting traffic management and traffic emissions is limited by the lack of a concentration-response function based on systematic review and meta-analysis of relevant studies. Using systematic methods, we identified papers containing quantitative estimates for nitrogen dioxide and the 12 month period prevalence of asthma symptoms in children in which the exposure contrast was within-community and dominated by traffic pollution. One estimate was selected from each study according to an a priori algorithm. Odds ratios were standardised to 10 μg/m(3) and summary estimates were obtained using random- and fixed-effects estimates. Eighteen studies were identified. Concentrations of nitrogen dioxide were estimated for the home address (12) and/or school (8) using a range of methods; land use regression (6), study monitors (6), dispersion modelling (4) and interpolation (2). Fourteen studies showed positive associations but only two associations were statistically significant at the 5 % level. There was moderate heterogeneity (I(2) = 32.8 %) and the random-effects estimate for the odds ratio was 1.06 (95 % CI 1.00 to 1.11). There was no evidence of small study bias. Individual studies tended to have only weak positive associations between nitrogen dioxide and asthma prevalence but the summary estimate bordered on statistical significance at the 5 % level. Although small, the potential impact on asthma prevalence could be considerable because of the high level of baseline prevalence in many cities. Whether the association is causal or indicates the effects of a correlated pollutant or other confounders, the estimate obtained by the meta-analysis would be appropriate for estimating impacts of traffic pollution on asthma prevalence

Birth defects after exposure to efavirenz-based antiretroviral therapy at conception/first trimester of pregnancy: a multicohort analysis

To investigate the association between efavirenz (EFV) use during conception or first trimester (T1) of pregnancy and the occurrence of birth defects