Fat mass index and airway hyperresponsiveness in Korean adults

ABSTRACT

Objective

Airway hyperresponsiveness (AHR) is associated with asthma and obesity, which is defined as a high body mass index. Body mass mainly comprises fat mass (FM) and muscle mass (MM), which are independent of each other. We investigated the effect of changes in FM over time on the development of asymptomatic AHR in adults.

Methods

This long-term longitudinal study included adults who were underwent health checkups at the Seoul National University Hospital Gangnam Center. The participants underwent two methacholine bronchial provocation tests with a follow-up period (between the first and second tests) of more than 3 years and bioelectrical impedance analysis (BIA) at all visits. FM index (FMI; FM normalized for height) and MM index (MMI; MM normalized for height) were calculated using BIA.

Results

The study included 328 adult participants (61 women and 267 men). The mean number of BIA measurements was 6.96 and the follow-up duration was 6.69 years. In total, 13 participants showed a positive conversion of AHR. Multivariate analysis indicated that a high rate of change in FMI ([g/m²]/year), not MMI, was significantly associated with the risk of AHR development (P = 0.037) after adjustment for age, sex, smoking status, and FEV1 predicted.

Conclusion

A rapid gain of FM over time may be a risk factor for developing AHR in adults. Prospective studies are needed to confirm our results and evaluate the role of FM reduction in preventing AHR development in obese adults.

KEYWORDS:

• Asthma
• airway hyperresponsiveness
• body composition
• fat mass
• muscle mass
• obesity

Declaration of financial/other relationships

The authors have no relevant affiliations or financial involvement with any organization or entity with a financial interest in or financial conflict with the subject matter or materials discussed in the manuscript. This includes employment, consultancies, honoraria, stock ownership or options, expert testimony, grants or patents received or pending, or royalties. Peer reviewers on this manuscript have no relevant financial or other relationships to disclose.

Author contributions

H-W Park and J-S Shim conceived and designed the study. J-S Shim, S-S Kim, SH Lee, and H-W Park conducted the primary analysis and data collection. H-W Park, J-S Shim, and S-S Kim interpreted data and prepared the first draft of the manuscript. All authors reviewed the draft for intellectual content, and approved submission of the final version of the manuscript.

Additional information

Funding

This work was supported by the New Faculty Startup Fund from Seoul National University (No. 800-20200260) to Heung-Woo Park.