Exhaled breath temperature, a noninvasive method for assessing inflammation in asthmatics: Study

New Delhi: Asthma is defined by persistent airway inflammation and remodeling. Exhaled breath temperature (EBT) measurement is a simple, safe, and non-invasive method for detecting airway inflammation. In this study, Bhupendra Singh Yadav and his team found out that, in asthma patients, EBT may be utilized as an additional technique for the non-invasive evaluation of airway inflammation and remodeling.

The purpose of this study was to measure airway inflammation and remodeling in asthma patients non-invasively by measuring EBT and to link it with systemic indicators of inflammation and remodeling and the findings of this study were published in the Journal of the Association of Physicians of India on 24th February 2021.

The study included 24 male asthma patients and 23 age and gender-matched healthy controls. Spirometry was used to assess forced expiratory volume in 1 second (FEV1), forced vital capacity (FVC), and peak expiratory flow rate after EBT and core body temperature were recorded (PEFR). ELISA was used to measure serum levels of interleukin-6 (IL-6), vascular endothelial growth factor (VEGF), matrix metalloproteinase-9 (MMP-9) and tissue inhibitor of matrix metalloproteinase-1 (TIMP-1).

In this study, researchers detected considerably greater plateau EBT in asthma patients compared to controls, which is consistent with prior studies, but a negligible difference in the rate of increase of the EBT curve (slope) between two groups, which is inconsistent with previous results. Out of the two metrics, the plateau of EBT appears to be more dependable than the slope of the EBT curve, which fluctuates with the rate and depth of tidal breathing. It also demonstrates significant inter-and intra-individual variance in asthma patients. In the current study, asthma patients had substantially higher levels of serum IL-6, VEGF, MMP-9, and TIMP-1 when compared to the control group. Despite the fact that these serum indicators are increased in asthma patients, they do not have a significant correlation with exhaled breath temperature.

The researchers talked about the possible prospects of EBT in asthmatic inflammation and remodeling and concluded by reporting further research with a larger sample size from a diverse population and an improved approach is required to establish the clinical value of the EBT for routine screening of asthma patients since the same has to be established in an out-patient environment.

Reference:

Yadav BS, Bade G, Guleria R, Talwar A. Exhaled Breath Temperature and Systemic Biomarkers for Assessment of Airway Inflammation in Asthmatics. J Assoc Physicians India. 2021 Jul;69(7):11-12. PMID: 34431272