Vitamin D for the management of asthma.

BACKGROUND: Since the previous Cochrane Review on this topic in 2016, debate has continued surrounding a potential role for vitamin D in reducing risk of asthma exacerbation and improving asthma control. We therefore conducted an updated meta-analysis to include data from new trials completed since this date. OBJECTIVES: To evaluate the effectiveness and safety of administration of vitamin D or its hydroxylated metabolites in reducing the risk of severe asthma exacerbations (defined as those requiring treatment with systemic corticosteroids) and improving asthma symptom control. SEARCH METHODS: We searched the Cochrane Airways Group Trial Register and reference lists of articles. We contacted the authors of studies in order to identify additional trials. Date of last search: 8 September 2022. SELECTION CRITERIA: We included double-blind, randomised, placebo-controlled trials of vitamin D in children and adults with asthma evaluating exacerbation risk or asthma symptom control, or both. DATA COLLECTION AND ANALYSIS: Four review authors independently applied study inclusion criteria, extracted the data, and assessed risk of bias. We obtained missing data from the authors where possible. We reported results with 95% confidence intervals (CIs). The primary outcome was the incidence of severe asthma exacerbations requiring treatment with systemic corticosteroids. Secondary outcomes included the incidence of asthma exacerbations precipitating an emergency department visit or requiring hospital admission, or both, end-study childhood Asthma Control Test (cACT) or Asthma Control Test (ACT) scores, and end-study % predicted forced expiratory volume in one second (FEV1). We performed subgroup analyses to determine whether the effect of vitamin D on risk of asthma exacerbation was modified by baseline vitamin D status, vitamin D dose, frequency of dosing regimen, form of vitamin D given, and age of participants. MAIN RESULTS: We included 20 studies in this review; 15 trials involving a total of 1155 children and five trials involving a total of 1070 adults contributed data to analyses. Participant ages ranged from 1 to 84 years, with two trials providing data specific to participants under five years (n = 69) and eight trials providing data specific to participants aged 5 to 16 (n = 766). Across the trials, 1245 participants were male and 1229 were female, with two studies not reporting sex distribution. Fifteen trials contributed to the primary outcome analysis of exacerbations requiring systemic corticosteroids. The duration of trials ranged from three to 40 months; all but two investigated effects of administering cholecalciferol (vitamin D3). As in the previous Cochrane Review, the majority of participants had mild to moderate asthma, and profound vitamin D deficiency (25-hydroxyvitamin D (25(OH)D) < 25 nmol/L) at baseline was rare. Administration of vitamin D or its hydroxylated metabolites did not reduce or increase the proportion of participants experiencing one or more asthma exacerbations treated with systemic corticosteroids (odds ratio (OR) 1.04, 95% CI 0.81 to 1.34; I2 = 0%; 14 studies, 1778 participants; high-quality evidence). This equates to an absolute risk of 226 per 1000 (95% CI 185 to 273) in the pooled vitamin D group, compared to a baseline risk of 219 participants per 1000 in the pooled placebo group. We also found no effect of vitamin D supplementation on the rate of exacerbations requiring systemic corticosteroids (rate ratio 0.86, 95% CI 0.62 to 1.19; I2 = 60%; 10 studies, 1599 participants; high-quality evidence), or the time to first exacerbation (hazard ratio 0.82, 95% CI 0.59 to 1.15; I2 = 22%; 3 studies, 850 participants; high-quality evidence). Subgroup analysis did not reveal any evidence of effect modification by baseline vitamin D status, vitamin D dose, frequency of dosing regimen, or age. A single trial investigating administration of calcidiol reported a benefit of the intervention for the primary outcome of asthma control. Vitamin D supplementation did not influence any secondary efficacy outcome meta-analysed, which were all based on moderate- or high-quality evidence. We observed no effect on the incidence of serious adverse events (OR 0.89, 95% CI 0.56 to 1.41; I2 = 0%; 12 studies, 1556 participants; high-quality evidence). The effect of vitamin D on fatal asthma exacerbations was not estimable, as no such events occurred in any trial. Six studies reported adverse reactions potentially attributable to vitamin D. These occurred across treatment and control arms and included hypercalciuria, hypervitaminosis D, kidney stones, gastrointestinal symptoms and mild itch. In one trial, we could not ascertain the total number of participants with hypercalciuria from the trial report. We assessed three trials as being at high risk of bias in at least one domain; none of these contributed data to the analysis of the outcomes reported above. Sensitivity analyses that excluded these trials from each outcome to which they contributed did not change the null findings. AUTHORS' CONCLUSIONS: In contrast to findings of our previous Cochrane Review on this topic, this updated review does not find evidence to support a role for vitamin D supplementation or its hydroxylated metabolites to reduce risk of asthma exacerbations or improve asthma control. Participants with severe asthma and those with baseline 25(OH)D concentrations < 25 nmol/L were poorly represented, so further research is warranted here. A single study investigating effects of calcidiol yielded positive results, so further studies investigating effects of this metabolite are needed.

ANTECEDENTES: Desde la revisión Cochrane anterior sobre este tema en 2016, ha continuado el debate en torno a una posible función de la vitamina D en la reducción del riesgo de exacerbación del asma y la mejora de su control. Por lo tanto, se realizó un metanálisis actualizado para incluir los datos de los nuevos ensayos completados desde esta fecha. OBJETIVOS: Evaluar la eficacia y seguridad de la administración de vitamina D o sus metabolitos hidroxilados para reducir el riesgo de exacerbaciones graves del asma (definidas como aquellas que requieren tratamiento con corticosteroides sistémicos) y mejorar el control de sus síntomas. MÉTODOS DE BÚSQUEDA: Se buscó en el registro de ensayos del Grupo Cochrane de Vías respiratorias (Cochrane Airways Group) y en las listas de referencias de los artículos. Se estableció contacto con los autores de los estudios para identificar ensayos adicionales. Fecha de la última búsqueda: 8 de septiembre de 2022. CRITERIOS DE SELECCIÓN: Se incluyeron los ensayos doble ciego, aleatorizados, controlados con placebo de vitamina D en niños y adultos con asma que evaluaron el riesgo de exacerbación o el control de los síntomas del asma, o ambos. OBTENCIÓN Y ANÁLISIS DE LOS DATOS: Cuatro autores de la revisión aplicaron de forma independiente los criterios de inclusión de los estudios, extrajeron los datos y evaluaron el riesgo de sesgo. Cuando fue posible, se obtuvieron los datos faltantes a través de los autores de los estudios. Los resultados se informaron con intervalos de confianza (IC) del 95%. El desenlace principal fue la incidencia de exacerbaciones graves del asma que requirieron tratamiento con corticosteroides sistémicos. Los desenlaces secundarios incluyeron la incidencia de exacerbaciones del asma que precipitaron acudir al servicio de urgencias o requirieron ingreso hospitalario, o ambas, las puntuaciones de la childhood Asthma Control Test (cACT) o la Asthma Control Test (ACT) al final del estudio, y el % previsto de volumen espiratorio forzado en un segundo (VEF1) al final del estudio. Se realizaron análisis de subgrupos para determinar si el efecto de la vitamina D sobre el riesgo de exacerbación del asma se veía modificado por el estado inicial de vitamina D, la dosis de vitamina D, la frecuencia de la posología, la formulación de la vitamina D administrada y la edad de los participantes. RESULTADOS PRINCIPALES: En esta revisión se incluyeron 20 estudios; 15 ensayos con un total de 1155 niños y cinco ensayos con un total de 1070 adultos aportaron datos para los análisis. Las edades de los participantes variaron entre 1 y 84 años, con dos ensayos que proporcionaron datos específicos de participantes menores de 5 años (n = 69) y ocho ensayos que proporcionaron datos específicos de participantes de 5 a 16 años (n = 766). En todos los ensayos, 1245 participantes eran hombres y 1229 mujeres, y dos estudios no informaron acerca de la distribución por sexos. Quince ensayos contribuyeron al análisis del desenlace principal: exacerbaciones que requirieron corticosteroides sistémicos. La duración de los ensayos fue de entre 3 y 40 meses; todos menos dos investigaron los efectos de la administración de colecalciferol (vitamina D3). Al igual que en la revisión Cochrane anterior, la mayoría de los participantes presentaban asma de leve a moderada y la deficiencia importante de vitamina D (25­hidroxivitamina D [25(OH)D] < 25 nmol/l) al inicio del estudio fue poco frecuente. La administración de vitamina D o sus metabolitos hidroxilados no redujo ni aumentó la proporción de participantes que presentaron una o más exacerbaciones del asma tratada con corticosteroides sistémicos (odds ratio [OR] 1,04; IC del 95%: 0,81 a 1,34; I2 = 0%; 14 estudios, 1778 participantes; evidencia de calidad alta). Esto equivale a un riesgo absoluto de 226 por cada 1000 (IC del 95%: 185 a 273) en el grupo de vitamina D agrupado, en comparación con un riesgo inicial de 219 participantes por cada 1000 en el grupo placebo agrupado. Tampoco se encontraron efectos de la administración de suplementos de vitamina D sobre la tasa de exacerbaciones que requirieron corticosteroides sistémicos (cociente de tasas 0,86; IC del 95%: 0,62 a 1,19; I2 = 60%; 10 estudios, 1599 participantes; evidencia de calidad alta) ni sobre el tiempo transcurrido hasta la primera exacerbación (cociente de riesgos instantáneos 0,82; IC del 95%: 0,59 a 1,15; I2 = 22%; tres estudios, 850 participantes; evidencia de calidad alta). El análisis de subgrupos no reveló una evidencia de modificación del efecto en función del estado inicial de vitamina D, la dosis de vitamina D, la frecuencia de la posología ni la edad. Un único ensayo que investigó la administración de calcidiol informó sobre un efecto beneficioso de la intervención en el desenlace principal de control del asma. La administración de suplementos de vitamina D no influyó en ninguno de los desenlaces secundarios de eficacia metanalizados, todos ellos basados en evidencia de calidad moderada o alta. No se observaron efectos sobre la incidencia de eventos adversos graves (OR 0,89; IC del 95%: 0,56 a 1,41; I2 = 0%; 12 estudios, 1556 participantes; evidencia de calidad alta). No fue posible determinar el efecto de la vitamina D sobre las exacerbaciones mortales del asma ya que no se produjeron tales eventos en ningún ensayo. Seis estudios informaron sobre la presencia de reacciones adversas potencialmente atribuibles a la vitamina D. Estas se dieron en los grupos de tratamiento y control e incluyeron hipercalciuria, hipervitaminosis D, cálculos renales, síntomas gastrointestinales y prurito leve. En un ensayo, no fue posible determinar el número total de participantes con hipercalciuria a partir del informe del ensayo. Tres ensayos se consideraron con alto riesgo de sesgo en al menos un dominio; ninguno de ellos aportó datos al análisis de los desenlaces informados anteriormente. Los análisis de sensibilidad que excluyeron estos ensayos de cada desenlace al que contribuyeron no cambiaron los hallazgos nulos. CONCLUSIONES DE LOS AUTORES: En contraposición con los hallazgos de la revisión Cochrane anterior sobre este tema, esta revisión actualizada no encuentra evidencia que respalde una función de los suplementos de vitamina D o sus metabolitos hidroxilados en la reducción del riesgo de exacerbaciones del asma o la mejoría del control del asma. Los participantes con asma grave y aquellos con concentraciones iniciales de 25(OH)D < 25 nmol/l estuvieron escasamente representados, por lo que se justifica la realización de más estudios de investigación. Un único estudio que investigó los efectos del calcidiol proporcionó resultados positivos, por lo que se necesitan más estudios que investiguen los efectos de este metabolito.

Perceptions surrounding the possible interaction between physical activity, pollution and asthma in children and adolescents with and without asthma.

A cornerstone of asthma management is maintaining physical activity (PA), but this may lead to increased exposure to, and deeper inhalation of, pollutants. Furthermore, children and adolescents may be more susceptible to the deleterious impacts of such exposures. Despite the recent air quality campaigns and media coverage surrounding the dangers of air pollution to respiratory health, few target children and their understanding of such issues.Using semi structured interviews, understanding of PA, air pollution and their interaction was explored with 25 youth aged 7-17 years. Utilising NVIVO 12 software, an atheoretical, inductive thematic analysis was conducted to identify key themes which were subsequently presented as pen profiles with the number of common responses within a theme indicative of its strength.The majority (88%) of youth's indicated traffic-related air pollution and global manufacturing as key sources of air pollution. Whilst all youths were aware of outdoor pollution, only 52% were aware of indoor air pollutants, of which 62% had asthma. Despite some uncertainty, all youths described pollution in a negative fashion, with 52% linking air pollution to undesirable effects on health, specifically respiratory health. PA in a polluted area was thought to be more dangerous than beneficial by 44%, although 24% suggested the benefits of PA would outweigh any detriment from pollution.Youth are aware of, and potentially compensate for, the interaction between air pollution and PA. Strategies are needed to allow youth to make more informed decisions regarding how to promote PA whilst minimising exposure to air pollution.

Ethical and Information Governance Considerations for Promoting Digital Social Interventions in Primary Care.

Promoting online peer support beyond the informal sector to statutory health services requires ethical considerations and evidence-based knowledge about its impact on patients, health care professionals, and the wider health care system. Evidence on the effectiveness of digital interventions in primary care is sparse, and definitive guidance is lacking on the ethical concerns arising from the use of social media as a means for health-related interventions and research. Existing literature examining ethical issues with digital interventions in health care mainly focuses on apps, electronic health records, wearables, and telephone or video consultations, without necessarily covering digital social interventions, and does not always account for primary care settings specifically. Here we address the ethical and information governance aspects of undertaking research on the promotion of online peer support to patients by primary care clinicians, related to medical and public health ethics.

Integrating polygenic risk scores in the prediction of type 2 diabetes risk and subtypes in British Pakistanis and Bangladeshis: A population-based cohort study.

BACKGROUND: Type 2 diabetes (T2D) is highly prevalent in British South Asians, yet they are underrepresented in research. Genes & Health (G&H) is a large, population study of British Pakistanis and Bangladeshis (BPB) comprising genomic and routine health data. We assessed the extent to which genetic risk for T2D is shared between BPB and European populations (EUR). We then investigated whether the integration of a polygenic risk score (PRS) for T2D with an existing risk tool (QDiabetes) could improve prediction of incident disease and the characterisation of disease subtypes. METHODS AND FINDINGS: In this observational cohort study, we assessed whether common genetic loci associated with T2D in EUR individuals were replicated in 22,490 BPB individuals in G&H. We replicated fewer loci in G&H (n = 76/338, 22%) than would be expected given power if all EUR-ascertained loci were transferable (n = 101, 30%; p = 0.001). Of the 27 transferable loci that were powered to interrogate this, only 9 showed evidence of shared causal variants. We constructed a T2D PRS and combined it with a clinical risk instrument (QDiabetes) in a novel, integrated risk tool (IRT) to assess risk of incident diabetes. To assess model performance, we compared categorical net reclassification index (NRI) versus QDiabetes alone. In 13,648 patients free from T2D followed up for 10 years, NRI was 3.2% for IRT versus QDiabetes (95% confidence interval (CI): 2.0% to 4.4%). IRT performed best in reclassification of individuals aged less than 40 years deemed low risk by QDiabetes alone (NRI 5.6%, 95% CI 3.6% to 7.6%), who tended to be free from comorbidities and slim. After adjustment for QDiabetes score, PRS was independently associated with progression to T2D after gestational diabetes (hazard ratio (HR) per SD of PRS 1.23, 95% CI 1.05 to 1.42, p = 0.028). Using cluster analysis of clinical features at diabetes diagnosis, we replicated previously reported disease subgroups, including Mild Age-Related, Mild Obesity-related, and Insulin-Resistant Diabetes, and showed that PRS distribution differs between subgroups (p = 0.002). Integrating PRS in this cluster analysis revealed a Probable Severe Insulin Deficient Diabetes (pSIDD) subgroup, despite the absence of clinical measures of insulin secretion or resistance. We also observed differences in rates of progression to micro- and macrovascular complications between subgroups after adjustment for confounders. Study limitations include the absence of an external replication cohort and the potential biases arising from missing or incorrect routine health data. CONCLUSIONS: Our analysis of the transferability of T2D loci between EUR and BPB indicates the need for larger, multiancestry studies to better characterise the genetic contribution to disease and its varied aetiology. We show that a T2D PRS optimised for this high-risk BPB population has potential clinical application in BPB, improving the identification of T2D risk (especially in the young) on top of an established clinical risk algorithm and aiding identification of subgroups at diagnosis, which may help future efforts to stratify care and treatment of the disease.

Digital interventions to improve adherence to maintenance medication in asthma.

BACKGROUND: Asthma is the most common chronic lung condition worldwide, affecting 334 million adults and children globally. Despite the availability of effective treatment, such as inhaled corticosteroids (ICS), adherence to maintenance medication remains suboptimal. Poor ICS adherence leads to increased asthma symptoms, exacerbations, hospitalisations, and healthcare utilisation. Importantly, suboptimal use of asthma medication is a key contributor to asthma deaths. The impact of digital interventions on adherence and asthma outcomes is unknown. OBJECTIVES: To determine the effectiveness of digital interventions for improving adherence to maintenance treatments in asthma. SEARCH METHODS: We identified trials from the Cochrane Airways Trials Register, which contains studies identified through multiple electronic searches and handsearches of other sources. We also searched trial registries and reference lists of primary studies. We conducted the most recent searches on 1 June 2020, with no restrictions on language of publication. A further search was run in October 2021, but studies were not fully incorporated. SELECTION CRITERIA: We included randomised controlled trials (RCTs) including cluster- and quasi-randomised trials of any duration in any setting, comparing a digital adherence intervention with a non-digital adherence intervention or usual care. We included adults and children with a clinical diagnosis of asthma, receiving maintenance treatment. DATA COLLECTION AND ANALYSIS: We used standard methodological procedures for data collection. We used GRADE to assess quantitative outcomes where data were available. MAIN RESULTS: We included 40 parallel randomised controlled trials (RCTs) involving adults and children with asthma (n = 15,207), of which eight are ongoing studies. Of the included studies, 30 contributed data to at least one meta-analysis. The total number of participants ranged from 18 to 8517 (median 339). Intervention length ranged from two to 104 weeks. Most studies (n = 29) reported adherence to maintenance medication as their primary outcome; other outcomes such as asthma control and quality of life were also commonly reported. Studies had low or unclear risk of selection bias but high risk of performance and detection biases due to inability to blind the participants, personnel, or outcome assessors. A quarter of the studies had high risk of attrition bias and selective outcome reporting. We examined the effect of digital interventions using meta-analysis for the following outcomes: adherence (16 studies); asthma control (16 studies); asthma exacerbations (six studies); unscheduled healthcare utilisation (four studies); lung function (seven studies); and quality of life (10 studies). Pooled results showed that patients receiving digital interventions may have increased adherence (mean difference of 14.66 percentage points, 95% confidence interval (CI) 7.74 to 21.57; low-certainty evidence); this is likely to be clinically significant in those with poor baseline medication adherence. Subgroup analysis by type of intervention was significant (P = 0.001), with better adherence shown with electronic monitoring devices (EMDs) (23 percentage points over control, 95% CI 10.84 to 34.16; seven studies), and with short message services (SMS) (12 percentage points over control, 95% CI 6.22 to 18.03; four studies). No significant subgroup differences were seen for interventions having an in-person component versus fully digital interventions, adherence feedback, one or multiple digital components to the intervention, or participant age. Digital interventions were likely to improve asthma control (standardised mean difference (SMD) 0.31 higher, 95% CI 0.17 to 0.44; moderate-certainty evidence) - a small but likely clinically significant effect. They may reduce asthma exacerbations (risk ratio 0.53, 95% CI 0.32 to 0.91; low-certainty evidence). Digital interventions may result in a slight change in unscheduled healthcare utilisation, although some studies reported no or a worsened effect. School or work absence data could not be included for meta-analysis due to the heterogeneity in reporting and the low number of studies. They may result in little or no difference in lung function (forced expiratory volume in one second (FEV1)): there was an improvement of 3.58% predicted FEV1, 95% CI 1.00% to 6.17%; moderate-certainty evidence); however, this is unlikely to be clinically significant as the FEV1 change is below 12%. Digital interventions likely increase quality of life (SMD 0.26 higher, 95% CI 0.07 to 0.45; moderate-certainty evidence); however, this is a small effect that may not be clinically significant. Acceptability data showed positive attitudes towards digital interventions. There were no data on cost-effectiveness or adverse events. Our confidence in the evidence was reduced by risk of bias and inconsistency. AUTHORS' CONCLUSIONS: Overall, digital interventions may result in a large increase in adherence (low-certainty evidence). There is moderate-certainty evidence that digital adherence interventions likely improve asthma control to a degree that is clinically significant, and likely increase quality of life, but there is little or no improvement in lung function. The review found low-certainty evidence that digital interventions may reduce asthma exacerbations. Subgroup analyses show that EMDs may improve adherence by 23% and SMS interventions by 12%, and interventions with an in-person element and adherence feedback may have greater benefits for asthma control and adherence, respectively. Future studies should include percentage adherence as a routine outcome measure to enable comparison between studies and meta-analysis, and use validated questionnaires to assess adherence and outcomes.

Superusers' Engagement in Asthma Online Communities: Asynchronous Web-Based Interview Study.

BACKGROUND: Superusers, defined as the 1% of users who write a large number of posts, play critical roles in online health communities (OHCs), catalyzing engagement and influencing other users' self-care. Their unique online behavior is key to sustaining activity in OHCs and making them flourish. Our previous work showed the presence of 20 to 30 superusers active on a weekly basis among 3345 users in the nationwide Asthma UK OHC and that the community would disintegrate if superusers were removed. Recruiting these highly skilled individuals for research purposes can be challenging, and little is known about superusers. OBJECTIVE: This study aimed to explore superusers' motivation to actively engage in OHCs, the difficulties they may face, and their interactions with health care professionals (HCPs). METHODS: An asynchronous web-based structured interview study was conducted. Superusers of the Asthma UK OHC and Facebook groups were recruited through Asthma UK staff to pilot and subsequently complete the questionnaire. Open-ended questions were analyzed using content analysis. RESULTS: There were 17 superusers recruited for the study (14 patients with asthma and 3 carers); the majority were female (15/17). The age range of participants was 18 to 75 years. They were active in OHCs for 1 to 6 years and spent between 1 and 20 hours per week reading and 1 and 3 hours per week writing posts. Superusers' participation in OHCs was prompted by curiosity about asthma and its medical treatment and by the availability of spare time when they were off work due to asthma exacerbations or retired. Their engagement increased over time as participants furthered their familiarity with the OHCs and their knowledge of asthma and its self-management. Financial or social recognition of the superuser role was not important; their reward came from helping and interacting with others. According to the replies provided, they showed careful judgment to distinguish what can be dealt with through peer advice and what needs input from HCPs. Difficulties were encountered when dealing with misunderstandings about asthma and its treatment, patients not seeking advice from HCPs when needed, and miracle cures or dangerous ideas. Out of 17 participants, only 3 stated that their HCPs were aware of their engagement with OHCs. All superusers thought that HCPs should direct patients to OHCs, provided they are trusted and moderated. In addition, 9 users felt that HCPs themselves should take part in OHCs. CONCLUSIONS: Superusers from a UK-wide online community are highly motivated, altruistic, and mostly female individuals who exhibit judgment about the complexity of coping with asthma and the limits of their advice. Engagement with OHCs satisfies their psychosocial needs. Future research should explore how to address their unmet needs, their interactions with HCPs, and the potential integration of OHCs in traditional healthcare.

Diabetes mellitus and latent tuberculosis infection: baseline analysis of a large UK cohort.

We conducted a cross-sectional analysis of baseline data from a UK cohort study which enrolled participants at risk of latent tuberculosis infection (LTBI, defined as a positive result for either of the two interferon gamma release assays). Binomial regression with a log link was used to estimate crude and adjusted prevalence ratios (PRs) and 95% CIs for the relationship between diabetes mellitus (DM) and LTBI. Adjusted for age, sex, ethnicity, body mass index and the presence of other immunocompromising conditions, DM was associated with a 15% higher prevalence of LTBI (adjusted PR=1.15, 95% CI 1.02 to 1.30, p=0.025). TRIAL REGISTRATION NUMBER: PREDICT is registered on clinicaltrials.gov (NCT01162265).

How Online Communities of People With Long-Term Conditions Function and Evolve: Network Analysis of the Structure and Dynamics of the Asthma UK and British Lung Foundation Online Communities.

BACKGROUND: Self-management support can improve health and reduce health care utilization by people with long-term conditions. Online communities for people with long-term conditions have the potential to influence health, usage of health care resources, and facilitate illness self-management. Only recently, however, has evidence been reported on how such communities function and evolve, and how they support self-management of long-term conditions in practice. OBJECTIVE: The aim of this study is to gain a better understanding of the mechanisms underlying online self-management support systems by analyzing the structure and dynamics of the networks connecting users who write posts over time. METHODS: We conducted a longitudinal network analysis of anonymized data from 2 patients' online communities from the United Kingdom: the Asthma UK and the British Lung Foundation (BLF) communities in 2006-2016 and 2012-2016, respectively. RESULTS: The number of users and activity grew steadily over time, reaching 3345 users and 32,780 posts in the Asthma UK community, and 19,837 users and 875,151 posts in the BLF community. People who wrote posts in the Asthma UK forum tended to write at an interval of 1-20 days and six months, while those in the BLF community wrote at an interval of two days. In both communities, most pairs of users could reach one another either directly or indirectly through other users. Those who wrote a disproportionally large number of posts (the superusers) represented 1% of the overall population of both Asthma UK and BLF communities and accounted for 32% and 49% of the posts, respectively. Sensitivity analysis showed that the removal of superusers would cause the communities to collapse. Thus, interactions were held together by very few superusers, who posted frequently and regularly, 65% of them at least every 1.7 days in the BLF community and 70% every 3.1 days in the Asthma UK community. Their posting activity indirectly facilitated tie formation between other users. Superusers were a constantly available resource, with a mean of 80 and 20 superusers active at any one time in the BLF and Asthma UK communities, respectively. Over time, the more active users became, the more likely they were to reply to other users' posts rather than to write new ones, shifting from a help-seeking to a help-giving role. This might suggest that superusers were more likely to provide than to seek advice. CONCLUSIONS: In this study, we uncover key structural properties related to the way users interact and sustain online health communities. Superusers' engagement plays a fundamental sustaining role and deserves research attention. Further studies are needed to explore network determinants of the effectiveness of online engagement concerning health-related outcomes. In resource-constrained health care systems, scaling up online communities may offer a potentially accessible, wide-reaching and cost-effective intervention facilitating greater levels of self-management.

Systematic meta-review of supported self-management for asthma: a healthcare perspective.

BACKGROUND: Supported self-management has been recommended by asthma guidelines for three decades; improving current suboptimal implementation will require commitment from professionals, patients and healthcare organisations. The Practical Systematic Review of Self-Management Support (PRISMS) meta-review and Reducing Care Utilisation through Self-management Interventions (RECURSIVE) health economic review were commissioned to provide a systematic overview of supported self-management to inform implementation. We sought to investigate if supported asthma self-management reduces use of healthcare resources and improves asthma control; for which target groups it works; and which components and contextual factors contribute to effectiveness. Finally, we investigated the costs to healthcare services of providing supported self-management. METHODS: We undertook a meta-review (systematic overview) of systematic reviews updated with randomised controlled trials (RCTs) published since the review search dates, and health economic meta-analysis of RCTs. Twelve electronic databases were searched in 2012 (updated in 2015; pre-publication update January 2017) for systematic reviews reporting RCTs (and update RCTs) evaluating supported asthma self-management. We assessed the quality of included studies and undertook a meta-analysis and narrative synthesis. RESULTS: A total of 27 systematic reviews (n = 244 RCTs) and 13 update RCTs revealed that supported self-management can reduce hospitalisations, accident and emergency attendances and unscheduled consultations, and improve markers of control and quality of life for people with asthma across a range of cultural, demographic and healthcare settings. Core components are patient education, provision of an action plan and regular professional review. Self-management is most effective when delivered in the context of proactive long-term condition management. The total cost (n = 24 RCTs) of providing self-management support is offset by a reduction in hospitalisations and accident and emergency visits (standard mean difference 0.13, 95% confidence interval -0.09 to 0.34). CONCLUSIONS: Evidence from a total of 270 RCTs confirms that supported self-management for asthma can reduce unscheduled care and improve asthma control, can be delivered effectively for diverse demographic and cultural groups, is applicable in a broad range of clinical settings, and does not significantly increase total healthcare costs. Informed by this comprehensive synthesis of the literature, clinicians, patient-interest groups, policy-makers and providers of healthcare services should prioritise provision of supported self-management for people with asthma as a core component of routine care. SYSTEMATIC REVIEW REGISTRATION: RECURSIVE: PROSPERO CRD42012002694 ; PRISMS: PROSPERO does not register meta-reviews.

Attitudes to participating in a birth cohort study, views from a multiethnic population: a qualitative study using focus groups.

BACKGROUND: Recruitment to birth cohort studies is a challenge. Few studies have addressed the attitudes of women about taking part in birth cohort studies particularly those from ethnic minority groups. OBJECTIVE: To seek the views of people from diverse ethnic backgrounds about participation in a proposed birth cohort examining the impact of infections. DESIGN AND SETTING: Eight focus groups of pregnant women and mothers of young children took place in GP surgeries and community centres in an ethnically diverse area of east London. Purposeful sampling and language support ensured representation of people from ethnic minority groups. Audio recordings were taken and transcripts were analysed using the Framework approach. MAIN OUTCOME MEASURES: The views of participants about taking part in the proposed birth cohort study, in particular concerning incentives to taking part, disincentives and attitudes to consenting children. RESULTS: There was more convergence of opinion than divergence across groups. Altruism, perceived health gains of participating and financial rewards were motivating factors for most women. Worries about causing harm to their child, inconvenience, time pressure and blood sample taking as well as a perceived lack of health gains were disincentives to most. Mistrust of researchers did not appear to be a significant barrier. The study indicates that ethnicity and other demographic factors influence attitudes to participation. CONCLUSIONS: To recruit better, birth cohort studies should incorporate financial and health gains as rewards for participation, promote the altruistic goals of research, give assurances regarding the safety of the participating children and sensitive data, avoid discomfort and maximize convenience. Ethnicity influences attitudes to participation in many ways, and researchers should explore these factors in their target population.

Vitamin D for the management of asthma.

BACKGROUND: Several clinical trials of vitamin D to prevent asthma exacerbation and improve asthma control have been conducted in children and adults, but a meta-analysis restricted to double-blind, randomised, placebo-controlled trials of this intervention is lacking. OBJECTIVES: To evaluate the efficacy of administration of vitamin D and its hydroxylated metabolites in reducing the risk of severe asthma exacerbations (defined as those requiring treatment with systemic corticosteroids) and improving asthma symptom control. SEARCH METHODS: We searched the Cochrane Airways Group Trial Register and reference lists of articles. We contacted the authors of studies in order to identify additional trials. Date of last search: January 2016. SELECTION CRITERIA: Double-blind, randomised, placebo-controlled trials of vitamin D in children and adults with asthma evaluating exacerbation risk or asthma symptom control or both. DATA COLLECTION AND ANALYSIS: Two review authors independently applied study inclusion criteria, extracted the data, and assessed risk of bias. We obtained missing data from the authors where possible. We reported results with 95% confidence intervals (CIs). MAIN RESULTS: We included seven trials involving a total of 435 children and two trials involving a total of 658 adults in the primary analysis. Of these, one trial involving 22 children and two trials involving 658 adults contributed to the analysis of the rate of exacerbations requiring systemic corticosteroids. Duration of trials ranged from four to 12 months, and the majority of participants had mild to moderate asthma. Administration of vitamin D reduced the rate of exacerbations requiring systemic corticosteroids (rate ratio 0.63, 95% CI 0.45 to 0.88; 680 participants; 3 studies; high-quality evidence), and decreased the risk of having at least one exacerbation requiring an emergency department visit or hospitalisation or both (odds ratio (OR) 0.39, 95% CI 0.19 to 0.78; number needed to treat for an additional beneficial outcome, 27; 963 participants; 7 studies; high-quality evidence). There was no effect of vitamin D on % predicted forced expiratory volume in one second (mean difference (MD) 0.48, 95% CI -0.93 to 1.89; 387 participants; 4 studies; high-quality evidence) or Asthma Control Test scores (MD -0.08, 95% CI -0.70 to 0.54; 713 participants; 3 studies; high-quality evidence). Administration of vitamin D did not influence the risk of serious adverse events (OR 1.01, 95% CI 0.54 to 1.89; 879 participants; 5 studies; moderate-quality evidence). One trial comparing low-dose versus high-dose vitamin D reported two episodes of hypercalciuria, one in each study arm. No other study reported any adverse event potentially attributable to administration of vitamin D. No participant in any included trial suffered a fatal asthma exacerbation. We did not perform a subgroup analysis to determine whether the effect of vitamin D on risk of severe exacerbation was modified by baseline vitamin D status, due to unavailability of suitably disaggregated data. We assessed two trials as being at high risk of bias in at least one domain; neither trial contributed data to the analysis of the outcomes reported above. AUTHORS' CONCLUSIONS: Meta-analysis of a modest number of trials in people with predominantly mild to moderate asthma suggests that vitamin D is likely to reduce both the risk of severe asthma exacerbation and healthcare use. It is as yet unclear whether these effects are confined to people with lower baseline vitamin D status; further research, including individual patient data meta-analysis of existing datasets, is needed to clarify this issue. Children and people with frequent severe asthma exacerbations were under-represented; additional primary trials are needed to establish whether vitamin D can reduce the risk of severe asthma exacerbation in these groups.

Implementing supported self-management for asthma: a systematic review and suggested hierarchy of evidence of implementation studies.

BACKGROUND: Asthma self-management remains poorly implemented in clinical practice despite overwhelming evidence of improved healthcare outcomes, reflected in guideline recommendations over three decades. To inform delivery in routine care, we synthesised evidence from implementation studies of self-management support interventions. METHODS: We systematically searched eight electronic databases (1980 to 2012) and research registers, and performed snowball and manual searches for studies evaluating implementation of asthma self-management in routine practice. We included, and adapted systematic review methodology to reflect, a broad range of implementation study designs. We extracted data on study characteristics, process measures (for example, action plan ownership), asthma control (for example, patient reported control questionnaires, days off school/work, symptom-free days) and use of health services (for example, admissions, emergency department attendances, unscheduled consultations). We assessed quality using the validated Downs and Black checklist, and conducted a narrative synthesis informed by Kennedy's whole systems theoretical approach (considering patient, practitioner and organisational components and the interaction between these). RESULTS: We included 18 studies (6 randomised trials, 2 quasi-experimental studies, 8 with historical controls and 3 with retrospective comparators) from primary, secondary, community and managed care settings serving a total estimated asthma population of 800,000 people in six countries. In these studies, targeting professionals (n = 2) improved process, but had no clinically significant effect on clinical outcomes. Targeting patients (n = 6) improved some process measures, but had an inconsistent impact on clinical outcomes. Targeting the organisation (n = 3) improved process measures, but had little/no effect on clinical outcomes. Interventions that explicitly addressed patient, professional and organisational factors (n = 7) showed the most consistent improvement in both process and clinical outcomes. Authors highlighted the importance of health system commitment, skills training for professionals, patient education programmes supported by regular reviews, and on-going evaluation of implementation effectiveness. CONCLUSIONS: Our methodology offers an exemplar of reviews synthesising the heterogeneous implementation literature. Effective interventions combined active engagement of patients, with training and motivation of professionals embedded within an organisation in which self-management is valued. Healthcare managers should consider how they can promote a culture of actively supporting self-management as a normal, expected, monitored and remunerated aspect of the provision of care. SYSTEMATIC REVIEW REGISTRATION: PROSPERO (registration number: CRD42012002898 ) Accessed 24 May 2015.

Health and illness beliefs in adults with tuberculosis infection during the COVID-19 pandemic in the UK.

Background: COVID-19 disrupted the TB prevention programme in the UK, especially for TB infection (TBI) care. We explore whether experience of the COVID-19 pandemic impacted on patients' perceptions of TBI and its treatment. Methods: Semi-structured interviews were conducted as part of the Research to Improve Detection and Treatment of TBI (RID-TB) programme, exploring perceptual and practical barriers to TBI treatment. Nineteen people diagnosed with TBI were interviewed between August 2020 and April 2021. Recordings were transcribed and analysed using a constant comparative approach, allowing for a dynamic and iterative exploration of themes. Themes are organised using the Perceptions and Practicalities Approach. Findings: Some participants perceived TBI as a risk factor for increased susceptibility to COVID-19, while some thought that treatment for TBI might protect against COVID-19 or mitigate its effects. Adaptations to TB services (e.g., remote follow-up) and integrated practices during the COVID-19 restrictions (e.g., medication being posted) addressed some practical barriers to TBI treatment. However, we identified beliefs about TBI and COVID-19 that are likely to act as barriers to engagement with TBI treatment, including: interpreting service delays as an indication of TBI not being serious enough for treatment and concerns about contracting COVID-19 in TB clinics. Interpretation: COVID-19 and TBI service delays influence people's perceptions and practical barriers to TBI treatment adherence. Failure to address these beliefs may lead to people's concerns about their treatment not being fully addressed. Utilised service adaptations like remote consultations to address practical barriers may be relevant beyond COVID-19. Funding: NIHR RID-TB Program (RP-PG-0217-20009).

Characterising sources of PM2·5 exposure for school children with asthma: a personal exposure study across six cities in sub-Saharan Africa.

BACKGROUND: Air pollution is the second largest risk to health in Africa, and children with asthma are particularly susceptible to its effects. Yet, there is a scarcity of air pollution exposure data from cities in sub-Saharan Africa. We aimed to identify potential exposure reduction strategies for school children with asthma living in urban areas in sub-Saharan Africa. METHODS: This personal exposure study was part of the Achieving Control of Asthma in Children in Africa (ACACIA) project. Personal exposure to particulate matter (PM) was monitored in school children in six cities in sub-Saharan Africa (Blantyre, Malawi; Durban, South Africa; Harare, Zimbabwe; Kumasi, Ghana; Lagos, Nigeria; and Moshi, Tanzania). Participants were selected if they were aged 12-16 years and had symptoms of asthma. Monitoring was conducted between June 21, and Nov 26, 2021, from Monday morning (approximately 1000 h) to Friday morning (approximately 1000 h), by use of a bespoke backpack with a small air pollution monitoring unit with an inbuilt Global Positioning System (GPS) data logger. Children filled in a questionnaire detailing potential sources of air pollution during monitoring and exposures were tagged into three different microenvironments (school, commute, and home) with GPS coordinates. Mixed-effects models were used to identify the most important determinants of children's PM2·5 (PM <2·5 µm in diameter) exposure. FINDINGS: 330 children were recruited across 43 schools; of these, 297 had valid monitoring data, and 1109 days of valid data were analysed. Only 227 (20%) of 1109 days monitored were lower than the current WHO 24 h PM2·5 exposure health guideline of 15 µg/m3. Children in Blantyre had the highest PM2·5 exposure (median 41·8 µg/m3), whereas children in Durban (16·0 µg/m3) and Kumasi (17·9 µg/m3) recorded the lowest exposures. Children had significantly higher PM2·5 exposures at school than at home in Kumasi (median 19·6 µg/m3vs 14·2 µg/m3), Lagos (32·0 µg/m3vs 18·0 µg/m3), and Moshi (33·1 µg/m3vs 23·6 µg/m3), while children in the other three cities monitored had significantly higher PM2·5 exposures at home and while commuting than at school (median 48·0 µg/m3 and 43·2 µg/m3vs 32·3 µg/m3 in Blantyre, 20·9 µg/m3 and 16·3 µg/m3vs 11·9 µg/m3 in Durban, and 22·7 µg/m3 and 25·4 µg/m3vs 16·4 µg/m3 in Harare). The mixed-effects model highlighted the following determinants for higher PM2·5 exposure: presence of smokers at home (23·0% higher exposure, 95% CI 10·8-36·4), use of coal or wood for cooking (27·1%, 3·9-56·3), and kerosene lamps for lighting (30·2%, 9·1-55·2). By contrast, 37·2% (95% CI 22·9-48·2) lower PM2·5 exposures were found for children who went to schools with paved grounds compared with those whose school grounds were covered with loose dirt. INTERPRETATION: Our study suggests that the most effective changes to reduce PM2·5 exposures in these cities would be to provide paving in school grounds, increase the use of clean fuel for cooking and light in homes, and discourage smoking within homes. The most efficient way to improve air quality in these cities would require tailored interventions to prioritise different exposure-reduction policies in different cities. FUNDING: UK National Institute for Health and Care Research.

DHCR7 mutations linked to higher vitamin D status allowed early human migration to northern latitudes.

BACKGROUND: Vitamin D is essential for a wide range of physiological processes including immune function and calcium homeostasis. Recent investigations have identified candidate genes which are strongly linked to concentrations of 25-hydroxyvitamin D. Since there is insufficient UVB radiation to induce year-round cutaneous synthesis of vitamin D at latitudes distant from the equator it is likely that these genes were subject to forces of natural selection. We used the fixation index (F(ST)) to measure differences in allele frequencies in 993 individuals from ten populations to identify the presence of evolutionary selection in genes in the vitamin D pathway. We then explored the length of haplotypes in chromosomes to confirm recent positive selection. RESULTS: We find evidence of positive selection for DHCR7, which governs availability of 7-dehydrocholesterol for conversion to vitamin D3 by the action of sunlight on the skin. We show that extended haplotypes related to vitamin D status are highly prevalent at Northern latitudes (Europe 0.72, Northeast Asia 0.41). The common DHCR7 haplotype underwent a recent selective sweep in Northeast Asia, with relative extended haplotype homozygosity of 5.03 (99th percentile). In contrast, CYP2R1, which 25-hydroxylates vitamin D, is under balancing selection and we found no evidence of recent selection pressure on GC, which is responsible for vitamin D transport. CONCLUSIONS: Our results suggest that genetic variation in DHCR7 is the major adaptation affecting vitamin D metabolism in recent evolutionary history which helped early humans to avoid severe vitamin D deficiency and enabled them to inhabit areas further from the equator.

Non-randomised feasibility study testing a primary care intervention to promote engagement in an online health community for adults with troublesome asthma: protocol.

INTRODUCTION: In the UK, approximately 4.3 million adults have asthma, with one-third experiencing poor asthma control, affecting their quality of life, and increasing their healthcare use. Interventions promoting emotional/behavioural self-management can improve asthma control and reduce comorbidities and mortality. Integration of online peer support into primary care services to foster self-management is a novel strategy. We aim to co-design and evaluate an intervention for primary care clinicians to promote engagement with an asthma online health community (OHC). Our protocol describes a 'survey leading to a trial' design as part of a mixed-methods, non-randomised feasibility study to test the feasibility and acceptability of the intervention. METHODS AND ANALYSIS: Adults on the asthma registers of six London general practices (~3000 patients) will be invited to an online survey, via text messages. The survey will collect data on attitudes towards seeking online peer support, asthma control, anxiety, depression, quality of life, information on the network of people providing support with asthma and demographics. Regression analyses of the survey data will identify correlates/predictors of attitudes/receptiveness towards online peer support. Patients with troublesome asthma, who (in the survey) expressed interest in online peer support, will be invited to receive the intervention, aiming to reach a recruitment target of 50 patients. Intervention will involve a one-off, face-to-face consultation with a practice clinician to introduce online peer support, sign patients up to an established asthma OHC, and encourage OHC engagement. Outcome measures will be collected at baseline and 3 months post intervention and analysed with primary care and OHC engagement data. Recruitment, intervention uptake, retention, collection of outcomes, and OHC engagement will be assessed. Interviews with clinicians and patients will explore experiences of the intervention. ETHICS AND DISSEMINATION: Ethical approval was obtained from a National Health Service Research Ethics Committee (reference: 22/NE/0182). Written consent will be obtained before intervention receipt and interview participation. Findings will be shared via dissemination to general practices, conference presentations and peer-reviewed publications. TRIAL REGISTRATION NUMBER: NCT05829265.

Experiences and behaviours of patients with asthma requesting prescriptions from primary care during medication shortages linked to the COVID-19 lockdown: insights from a qualitative analysis of a UK asthma online community.

BACKGROUND: Inhaler shortages were reported in the UK following declaration of the COVID-19 pandemic, prompting advice against stockpiling. AIM: To understand experiences and behaviours of patients with asthma requesting prescriptions from primary care during asthma medication shortages. DESIGN & SETTING: UK asthma online community, between March and December 2020. METHOD: Thematic analysis of posts identified using search terms 'shortage', 'out of stock', 'prescribe', and 'prescription'. RESULTS: Sixty-seven participants were identified (48 adults, two children, 17 unstated age). Factors leading to increased requests included the following: stockpiling; early ordering; realising inhalers were out of date; and doctors prescribing multiple medication items. Patients' anxieties that could lead to stockpiling included the following: fear of asthma attacks leading to admission and acquiring COVID-19 in hospital; lack of dose counters on some inhalers; and believing a lower amount of drug is delivered in the last actuations. Strategies adopted in relation to shortages or changes in treatment owing to out-of-stock medications included the following: starting stockpiling; ordering prescriptions early; contacting medical professionals for advice or alternative prescriptions; getting 'emergency prescriptions'; ordering online or privately; seeking medications in different pharmacies; contacting drug manufacturers; and keeping track of number of doses left in canisters. No evidence was found of anxiety-triggered asthma symptoms that required medications due to fear of COVID-19. Participants seemed to disregard advice against stockpiling. CONCLUSION: Better preparation is a key lesson from the COVID-19 pandemic. Clinicians, the pharmaceutical industry, and policymakers should use insights from this work to plan how to better manage medication shortages in future emergency situations.

Characterising professional drivers' exposure to traffic-related air pollution: Evidence for reduction strategies from in-vehicle personal exposure monitoring.

Professional drivers working in congested urban areas are required to work near harmful traffic related pollutants for extended periods, representing a significant, but understudied occupational risk. This study collected personal black carbon (BC) exposures for 141 drivers across seven sectors in London. The aim of the study was to assess the magnitude and the primary determinants of their exposure, leading to the formulation of targeted exposure reduction strategies for the occupation. Each participant's personal BC exposures were continuously measured using real-time monitors for 96 h, incorporating four shifts per participant. 'At work' BC exposures (3.1 ± 3.5 µg/m3) were 2.6 times higher compared to when 'not at work' (1.2 ± 0.7 µg/m3). Workers spent 19% of their time 'at work driving', however this activity contributed 36% of total BC exposure, highlighting the disproportionate effect driving had on their daily exposure. Taxi drivers experienced the highest BC exposures due to the time they spent working in congested central London, while emergency services had the lowest. Spikes in exposure were observed while driving and were at times greater than 100 µg/m3. The most significant determinants of drivers' exposures were driving in tunnels, congestion, location, day of week and time of shift. Driving with closed windows significantly reduced exposures and is a simple behaviour change drivers could implement. Our results highlight strategies by which employers and local policy makers can reduce professional drivers' exposure to traffic-related air pollution.

Promising peak flow diary compliance with an electronic peak flow meter and linked smartphone app.

Peak expiratory flow (PEF) monitoring is recommended in the management of asthma. However, compliance is poor, and this is often attributed to the burden of measurement and recording. The Smart Peak Flow (SPF) device and app allow self-measuring and self-monitoring of PEF. Compliance with self-monitoring was promising in 399 UK users, calling for research to confirm these results and explore its potential as an intervention to improve self-monitoring.