Body mass index affects asthma control test questionnaire scores

Title: Body mass index affects asthma control test questionnaire scores
Author(s): C. Mulvey V. Brennan G. Greene T.A. McCartan E. Mac Hale L. Lombard J. Walsh M. Quinn R.W. Costello
Institution: Royal College of Surgeons in Ireland
Poster: Click to view poster
Category: Asthma and COPD
Abstract: Asthma control is often assessed with the use of questionnaires. With levels of obesity rising globally, it is likely that associated comorbid conditions and deconditioning in baseline fitness may occur within asthma populations. This may lead to confusion between the effects of raised body mass index (BMI) and asthma symptoms. We hypothesised that asthma control test (ACT) scores are significantly impacted by BMI.

Analysis of a systematic review of clinical trials assessing additional therapies to ICS/LABA combinations yielded a significant result indicating BMI is reducing over time (coefficient -0.195, p 0.008, C.I. -0.335 - -0.054). This significance is lost when country of recruitment is accounted for.

Analysis of a combined dataset of two adherence randomised control trials (NCT01529697 and NCT02307669) to assess the relationship between ACT scores and BMI yielded a significant relationship indicating raised BMI results in lower ACT scores (coefficient -0.134, p 0.001, C.I. -0.214 – -0.054).

BMI has a significant effect on ACT scores which may lead clinicians to misinterpret asthma control. Clinical trials are increasingly conducted in countries with lower BMIs, therefore trial results may not apply to patient groups in clinical practice elsewhere, whose asthma may be complicated by raised BMI.