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Background: The imposition of restrictions on social mixing early in the COVID-19 pandemic was followed by a reduction in asthma exacerbations in multiple settings internationally. Temporal trends in social mixing, incident acute respiratory infections (ARI) and asthma exacerbations following relaxation of COVID-19 restrictions have not yet been described., Methods: We conducted a population-based longitudinal study in 2312 UK adults with asthma between November 2020 and April 2022. Details of face covering use, social mixing, incident ARI and severe asthma exacerbations were collected via monthly online questionnaires. Temporal changes in these parameters were visualised using Poisson generalised additive models. Multilevel logistic regression was used to test for associations between incident ARI and risk of asthma exacerbations, adjusting for potential confounders., Results: Relaxation of COVID-19 restrictions from April 2021 coincided with reduced face covering use (p<0.001), increased frequency of indoor visits to public places and other households (p<0.001) and rising incidence of COVID-19 (p<0.001), non-COVID-19 ARI (p<0.001) and severe asthma exacerbations (p=0.007). Incident non-COVID-19 ARI associated independently with increased risk of asthma exacerbation (adjusted OR 5.75, 95% CI 4.75 to 6.97) as did incident COVID-19, both prior to emergence of the omicron variant of SARS-CoV-2 (5.89, 3.45 to 10.04) and subsequently (5.69, 3.89 to 8.31)., Conclusions: Relaxation of COVID-19 restrictions coincided with decreased face covering use, increased social mixing and a rebound in ARI and asthma exacerbations. Associations between incident ARI and risk of severe asthma exacerbation were similar for non-COVID-19 ARI and COVID-19, both before and after emergence of the SARS-CoV-2 omicron variant., Study Registration Number: NCT04330599., Competing Interests: Competing interests: RAL declares membership of the Welsh Government COVID19 Technical Advisory Group. AS is a member of the Scottish Government Chief Medical Officer’s COVID-19 Advisory Group and its Standing Committee on Pandemics. He is also a member of the UK Government’s NERVTAG’s Risk Stratification Subgroup. All other authors declare that they have no competing interests., (© Author(s) (or their employer(s)) 2023. Re-use permitted under CC BY. Published by BMJ.)

Background: Longitudinal epidemiological data are scarce examining the relationship between dietary patterns and respiratory outcomes in childhood. We investigated whether three distinct dietary patterns in mid-childhood were associated with lung function and incident asthma in adolescence., Methods: In the Avon Longitudinal Study of Parents and Children, 'processed', 'traditional', and 'health-conscious' dietary patterns were identified using principal components analysis from food frequency questionnaires at 7 years of age. Post-bronchodilator forced expiratory volume in 1 s (FEV 1 ), forced vital capacity (FVC), and forced expiratory flow at 25-75% of FVC (FEF 25-75 ) were measured at 15.5 years and were transformed to z-scores based on the Global Lung Function Initiative curves. Incident asthma was defined by new cases of doctor-diagnosed asthma at age 11 or 14 years., Results: In multivariable-adjusted models, the 'health-conscious' pattern was positively associated with FEV 1 (regression coefficient comparing top versus bottom quartile of pattern score 0.16, 95% CI 0.01 to 0.31, P for trend 0.04) and FVC (0.18, 95% CI 0.04 to 0.33, P for trend 0.02), while the 'processed' pattern was negatively associated with FVC (- 0.17, 95% CI - 0.33 to - 0.01, P for trend 0.03). Associations between the 'health-conscious' and 'processed' patterns and lung function were modified by SCGB1A1 and GPX4 gene polymorphisms. We found no evidence of an association between the 'traditional' pattern and lung function, nor between any pattern and FEF 25-75 or incident asthma., Conclusions: A 'health-conscious' diet in mid-childhood was associated with higher subsequent lung function, while a diet high in processed food was associated with lower lung function., (© 2023. The Author(s).)

Background: Longitudinal epidemiological data are scarce on the relationship between dietary intake of vitamin A and respiratory outcomes in childhood. We investigated whether a higher intake of preformed vitamin A or pro-vitamin β-carotene in mid-childhood is associated with higher lung function and with asthma risk in adolescence., Methods: In the Avon Longitudinal Study of Parents and Children, dietary intakes of preformed vitamin A and β-carotene equivalents were estimated by food frequency questionnaire at 7 years of age. Post-bronchodilator forced expiratory volume in 1 s (FEV 1 ), forced vital capacity (FVC) and forced expiratory flow at 25-75% of FVC (FEF 25-75% ) were measured at 15.5 years and transformed to z-scores. Incident asthma was defined by new cases of doctor-diagnosed asthma at age 11 or 14 years., Results: In multivariable adjusted models, a higher intake of preformed vitamin A was associated with higher lung function and a lower risk of incident asthma: comparing top versus bottom quartiles of intake, regression coefficients for FEV 1 and FEF 25-75% were 0.21 (95% CI 0.05-0.38; p trend =0.008) and 0.18 (95% CI 0.03-0.32; p trend =0.02), respectively; odds ratios for FEV 1 /FVC below the lower limit of normal and incident asthma were 0.49 (95% CI 0.27-0.90; p trend =0.04) and 0.68 (95% CI 0.47-0.99; p trend =0.07), respectively. In contrast, there was no evidence for association with β-carotene. We also found some evidence for modification of the associations between preformed vitamin A intake and lung function by BCMO1 , NCOR2 and SCGB1A1 gene polymorphisms., Conclusion: A higher intake of preformed vitamin A, but not β-carotene, in mid-childhood is associated with higher subsequent lung function and lower risk of fixed airflow limitation and incident asthma., Competing Interests: Conflict of interest: M. Talaei has nothing to disclose. Conflict of interest: D.A. Hughes has nothing to disclose. Conflict of interest: O. Mahmoud has nothing to disclose. Conflict of interest: P.M. Emmett reports grants from Nestle Nutrition, personal fees for consultancy from the European Food Safety Authority, outside the submitted work. Conflict of interest: R. Granell has nothing to disclose. Conflict of interest: S. Guerra has nothing to disclose. Conflict of interest: S.O. Shaheen has nothing to disclose., (Copyright ©The authors 2021.)

Longitudinal evidence on the relation between dietary intake of n -3 (ω-3) very-long-chain polyunsaturated fatty acids, i.e. eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA), in mid-childhood and asthma risk is scarce. We aimed to investigate whether a higher intake of EPA and DHA from fish in childhood is associated with a lower risk of incident asthma.In the Avon Longitudinal Study of Parents and Children, dietary intakes of EPA and DHA from fish were estimated by food frequency questionnaire at 7 years of age. We used logistic regression, controlling for confounders, to analyse associations between intake of EPA and DHA (quartiles) and incidence of doctor-diagnosed asthma at age 11 or 14 years, and explored potential effect modification by a fatty acid desaturase ( FADS ) polymorphism (rs1535). Replication was sought in the Swedish BAMSE birth cohort.There was no evidence of association between intake of EPA plus DHA from fish and incident asthma overall (n=4543). However, when stratified by FADS genotype, the odds ratio comparing the top versus bottom quartile among the 2025 minor G allele carriers was 0.49 (95% CI 0.31-0.79; p trend =0.006), but no inverse association was observed in the homozygous major A allele group (OR 1.43, 95% CI 0.83-2.46; p trend =0.19) (p interaction =0.006). This gene-nutrient interaction on incident asthma was replicated in BAMSE.In children with a common FADS variant, higher intake of EPA and DHA from fish in childhood was strongly associated with a lower risk of incident asthma up to mid-adolescence., Competing Interests: Conflict of interest: M. Talaei has nothing to disclose. Conflict of interest: E. Sdona has nothing to disclose. Conflict of interest: P.C. Calder has nothing to disclose. Conflict of interest: L.R. Jones reports grants from Nestle Nutrition, outside the submitted work. Conflict of interest: P.M. Emmett reports grants from Nestle Nutrition, outside the submitted work. Conflict of interest: R. Granell has nothing to disclose. Conflict of interest: A. Bergström has nothing to disclose. Conflict of interest: E. Melén has nothing to disclose. Conflict of interest: S.O. Shaheen has nothing to disclose., (Copyright ©The authors 2021.)