Background Cured meat intake—a recent carcinogenic factor—may increase the risk of COPD, but its association with asthma remains unknown. Though body mass index (BMI) is a likely risk factor for asthma, its role in the diet–asthma association as a mediator has never been studied. We investigated the association between cured meat intake and worsening asthma symptoms in adults, and the role of BMI as a potential mediator.
Methods Using data from the French prospective EGEA study (baseline: 2003–2007; follow-up: 2011–2013), we applied a mediation analysis in the counterfactual framework, a marginal structural model (MSM), to estimate the direct effect of baseline cured meat intake (<1, 1–3.9, ≥4 servings/week) on change in asthma symptom score (worsening or not), and the indirect effect mediated by BMI.
Results Among the 971 participants (mean age 43 years; 49% men; 42% with asthma), 20% reported worsening asthma symptoms during the mean follow-up time of 7 years. Using the MSM, we reported a positive direct effect of cured meat intake on worsening asthma symptoms (multivariable OR=1.76, 95% CI 1.01 to 3.06 for ≥4 vs <1 serving/week). We also reported an indirect effect mediated by BMI (OR=1.07; 95% CI 1.01 to 1.14), accounting for 14% of the total effect.
Conclusions Higher cured meat intake was associated with worsening asthma symptoms over time, through a direct effect and to a lesser extent an effect mediated by BMI. This research extends the effect of diet on asthma in adults.
- Asthma Epidemiology
Statistics from Altmetric.com
RN and RV contributed equally.
Contributors ZL, RN and RV: designed and conducted the research; BL, NLM, CP, VS, RN and RV: provided essential reagents or provided essential materials; ZL, MR, AB, OD, JG-A, VS, CAC, RN and RV: analysed data or performed statistical analysis; ZL, RN and RV: wrote the manuscript and had primary responsibility for final content; all authors read, edited and approved the final manuscript.
Funding This research was funded in part by Merck Sharp & Dohme (MSD), the GA2LEN project, Global Allergy and Asthma European Network, and Conseil scientifique AGIR pour les maladies chroniques, National Hospital program of clinical research (PHRC-national).
Competing interests None declared.
Ethics approval Ethical approval was obtained from the relevant institutional review board committees (Cochin Port-Royal Hospital and Necker-Enfants Malades Hospital, Paris).
Provenance and peer review Not commissioned; externally peer reviewed.
If you wish to reuse any or all of this article please use the link below which will take you to the Copyright Clearance Center’s RightsLink service. You will be able to get a quick price and instant permission to reuse the content in many different ways.