Asthmatics with increased triglyceride-glucose index are at elevated risk of exacerbations independent of type 2 inflammation: A prospective cohort study.

Abstract

The triglyceride-glucose (TyG) index is a new alternative marker for insulin resistance and metabolic dysfunction, which has recently been linked to lung health. However, the link among TyG index, type 2 (T2) inflammation and asthma is largely unexplored. To explore clinical, inflammatory characteristics and exacerbations in patients with asthma grouped by TyG index with or without T2 inflammation. This was a prospective cohort study with 12-month follow-up based on the Australasian Severe Asthma Network (ASAN). Patients with stable asthma were divided into the TyG^low and TyG^high groups by the 75^th percentile values of TyG index. Subgroups were analyzed based on T2 status. All participants with stable asthma (n=626) underwent multidimensional assessment and sputum induction. Univariate and multivariable negative binomial regression analyses were used to examine the relationship between asthma exacerbations and TyG index with or without T2 inflammation. Asthma patients in the TyG^high group (n = 156) had higher BMI, worse metabolic function and airway obstruction, more comorbidities including diabetes and metabolic syndrome, and increased risk of exacerbations independent of T2 inflammation, compared with the TyG^low group (n = 470). Furthermore, the TyG^high T2^low group were at significantly increased risk of moderate-to-severe exacerbations (adjusted incidence rate ratio (IRR)=2.54, 95%CI = [1.56, 4.15], P<0.001), emergency visits (adjusted IRR=7.88, 95%CI=[2.71, 22.92], P<0.001) and unscheduled visits (adjusted IRR=2.87, 95%CI = [1.65, 4.98], P<0.001). TyG index is a promising biomarker of asthma exacerbations, highlighting the clinical relevance of assessing TyG index in asthma management.