Levy ML, et al. Key recommendations for primary care from the 2022 Global Initiative for Asthma (GINA) update. NPJ Prim Care Respir Med. 2022;33(1):7. https://doi.org/10.1038/s41533-023-00330-1.

Article  Google Scholar 

WHO. Asthma. https://www.who.int/news-room/fact-sheets/detail/asthma. Last updated 6 May 2024. Accessed 25 Mar 2026.

Bloom CI, et al. Exacerbation risk and characterisation of the UK’s asthma population from infants to old age. Thorax. 2018;73(4):313–20. https://doi.org/10.1136/thoraxjnl-2017-210650.

Article  PubMed  Google Scholar 

Barnes PJ. Scientific rationale for inhaled combination therapy with long-acting beta2-agonists and corticosteroids. Eur Respir J. 2002;19(1):182–91. https://doi.org/10.1183/09031936.02.00283202.

Article  PubMed  Google Scholar 

Sears MR. Epidemiology of asthma exacerbations. J Allergy Clin Immunol. 2008;122(4):662–8. https://doi.org/10.1016/j.jaci.2008.08.003.

Article  PubMed  Google Scholar 

O’Byrne PM, et al. Low dose inhaled budesonide and formoterol in mild persistent asthma: the OPTIMA randomized trial. Am J Respir Crit Care Med. 2001;164(8 Pt 1):1392–7. https://doi.org/10.1164/ajrccm.164.8.2104102.

Article  PubMed  Google Scholar 

Jackson DJ, et al. Asthma exacerbations: origin, effect, and prevention. J Allergy Clin Immunol. 2011;128(6):1165–74. https://doi.org/10.1016/j.jaci.2011.10.024.

Article  PubMed  PubMed Central  Google Scholar 

Conn HO, Poynard T. Corticosteroids and peptic ulcer: meta-analysis of adverse events during steroid therapy. J Intern Med. 1994;236(6):619–32. https://doi.org/10.1111/j.1365-2796.1994.tb00855.x.

Article  PubMed  Google Scholar 

Narum S, et al. Corticosteroids and risk of gastrointestinal bleeding: a systematic review and meta-analysis. BMJ Open. 2014;4(5):e004587. https://doi.org/10.1136/bmjopen-2013-004587.

Article  PubMed  PubMed Central  Google Scholar 

Nielsen GL, et al. Risk of hospitalization resulting from upper gastrointestinal bleeding among patients taking corticosteroids: a register-based cohort study. Am J Med. 2001;111(7):541–5. https://doi.org/10.1016/s0002-9343(01)00941-x.

Article  PubMed  Google Scholar 

Hernández-Díaz S, Rodríguez LAG. Steroids and risk of upper gastrointestinal complications. Am J Epidemiol. 2001;153(11):1089–93. https://doi.org/10.1093/aje/153.11.1089.

Article  PubMed  Google Scholar 

Yao TC, et al. Association between oral corticosteroid bursts and severe adverse events: a nationwide population-based cohort study. Ann Intern Med. 2020;173(5):325–30. https://doi.org/10.7326/M20-0432.

Article  PubMed  Google Scholar 

Bloechliger M, et al. Adverse events profile of oral corticosteroids among asthma patients in the UK: cohort study with a nested case-control analysis. Respir Res. 2018;19:75. https://doi.org/10.1186/s12931-018-0742-y.

Article  PubMed  PubMed Central  Google Scholar 

Heatley H, et al. Observational UK cohort study to describe intermittent oral corticosteroid prescribing patterns and their association with adverse outcomes in asthma. Thorax. 2022. https://doi.org/10.1136/thorax-2022-219642.

Article  PubMed  PubMed Central  Google Scholar 

Price DB, et al. Adverse outcomes from initiation of systemic corticosteroids for asthma: long-term observational study. J Asthma Allergy. 2018;11:193–204. https://doi.org/10.2147/JAA.S176026.

Article  PubMed  PubMed Central  Google Scholar 

Skov IR, et al. Low-dose oral corticosteroids in asthma associates with increased morbidity and mortality. Eur Respir J. 2022. https://doi.org/10.1183/13993003.03054-2021.

Article  PubMed  Google Scholar 

Sullivan PW, et al. Oral corticosteroid exposure and adverse effects in asthmatic patients. J Allergy Clin Immunol. 2018;141(1):110-6 e7. https://doi.org/10.1016/j.jaci.2017.04.009.

Article  PubMed  Google Scholar 

Elliott MR, et al. An update on monoclonal antibody therapy to treat moderate-to-severe asthma: benefits, choices, and limitations. Am J Med. 2023;136(8):738–44. https://doi.org/10.1016/j.amjmed.2023.05.001.

Article  PubMed  Google Scholar 

Grogan CE, et al. Changing paradigms in asthma management. Am J Med Sci. 2025;369(6):653–6. https://doi.org/10.1016/j.amjms.2024.12.008.

Article  PubMed  Google Scholar 

Medicines & Healthcare Products Regulatory Agency. Clinical Practice Research Datalink. https://www.cprd.com/. Last updated 19 Sept 2025. Accessed 6 June 2026.

Wolf A, et al. Data resource profile: Clinical Practice Research Datalink (CPRD) Aurum. Int J Epidemiol. 2019;48(6):1740. https://doi.org/10.1093/ije/dyz034.

Article  PubMed  PubMed Central  Google Scholar 

Herrett E, et al. Validation and validity of diagnoses in the General Practice Research Database: a systematic review. Br J Clin Pharmacol. 2010;69(1):4–14. https://doi.org/10.1111/j.1365-2125.2009.03537.x.

Article  PubMed  PubMed Central  Google Scholar 

Jick SS, et al. Validity of the general practice research database. Pharmacotherapy. 2003;23(5):686–9. https://doi.org/10.1592/phco.23.5.686.32205.

Article  PubMed  Google Scholar 

Nissen F, et al. Validation of asthma recording in the Clinical Practice Research Datalink (CPRD). BMJ Open. 2017;7(8):e017474. https://doi.org/10.1136/bmjopen-2017-017474.

Article  PubMed  PubMed Central  Google Scholar 

Maclure M. The case-crossover design: a method for studying transient effects on the risk of acute events. Am J Epidemiol. 1991;133(2):144–53. https://doi.org/10.1093/oxfordjournals.aje.a115853.

Article  PubMed  Google Scholar 

Consiglio GP, et al. Case-crossover study design in pharmacoepidemiology: systematic review and recommendations. Pharmacoepidemiol Drug Saf. 2013;22(11):1146–53. https://doi.org/10.1002/pds.3508.

Article  PubMed  Google Scholar 

Delaney JA, Suissa S. The case-crossover study design in pharmacoepidemiology. Stat Methods Med Res. 2009;18(1):53–65. https://doi.org/10.1177/0962280208092346.

Article  PubMed  Google Scholar 

Bowerman C, et al. A race-neutral approach to the interpretation of lung function measurements. Am J Respir Crit Care Med. 2023;207(6):768–74. https://doi.org/10.1164/rccm.202205-0963OC.

Article  PubMed  Google Scholar 

Ahsberg K, et al. Impact of aspirin, NSAIDs, warfarin, corticosteroids and SSRIs on the site and outcome of non-variceal upper and lower gastrointestinal bleeding. Scand J Gastroenterol. 2010;45(12):1404–15. https://doi.org/10.3109/00365521.2010.510567.

Article  PubMed  Google Scholar 

Papi A, et al. Asthma. Lancet. 2018;391(10122):783–800. https://doi.org/10.1016/S0140-6736(17)33311-1.

Article  PubMed  Google Scholar 

Suissa S. Immortal time bias in pharmaco-epidemiology. Am J Epidemiol. 2008;167(4):492–9. https://doi.org/10.1093/aje/kwm324.

Article  PubMed  Google Scholar 

Hernan MA, et al. Specifying a target trial prevents immortal time bias and other self-inflicted injuries in observational analyses. J Clin Epidemiol. 2016;79:70–5. https://doi.org/10.1016/j.jclinepi.2016.04.014.

Article  PubMed  PubMed Central  Google Scholar 

Doroudchi A, et al. Asthma biologics Comparing trial designs, patient cohorts and study results. Ann Allerg Asthma Im. 2020;124(1):44–56. https://doi.org/10.1016/j.anai.2019.10.016.

Article  Google Scholar 

Gauvreau GM, et al. Benralizumab for allergic asthma: a randomised, double-blind, placebo-controlled trial. Eur Respir J. 2024. https://doi.org/10.1183/13993003.00512-2024.