In patients with severe asthma, ≥3 exacerbations in the preceding year were associated with adverse body composition, including lower skeletal muscle density (12.1 vs. 18.3 HU; p=0.002).
Cohort (n=267)
Is increased asthma exacerbation burden associated with adverse extra-pulmonary body composition metrics measured on CT?
Greater asthma exacerbation burden is associated with adverse extra-pulmonary body composition changes, including reduced muscle density and increased visceral adiposity.
Absolute Event Rate: 12.1% vs 18.3%
p-value: p=0.002
Abstract Rationale Metabolic dysfunction in asthma is linked to more difficult-to-control disease and increased symptom severity. Skeletal muscle and visceral adiposity reflect systemic metabolic impairment; notably, low muscle mass predicts lung function decline independent of traditional markers. However, the association of exacerbation burden and quantitative thoracic body composition metrics remains unclear. We hypothesized that increased asthma exacerbations are associated with adverse extra-pulmonary body composition metrics measured on computed tomography (CT) specifically (skeletal muscle density (SMD), intermuscular adipose tissue (IMAT), visceral adipose tissue (VAT), liver density, and aortic calcification). Methods The Severe Asthma Research Program (SARP) is a longitudinal cohort of individuals with severe asthma. All SARP III and IV participants with chest CT imaging and exacerbation data were included (N = 267, 455 person-visits). Exacerbations were assessed in the year preceding a CT scan and categorized as (0, 1-2, 3). CT body composition measures (T12 SMD, IMAT, VAT, liver density, and aortic calcification were measured using a fully automated, artificial intelligence (AI) based pipeline for body composition from CT images acquired using a standard multidetector-row CT scanner. To account for the repeated measures design, generalized estimating equations (GEE) characterized the association of systemic adiposity measures and exacerbations. Models were unadjusted and age-and-sex adjusted. Results The N = 267 participants were a mean (SD) 49.9 (14.5) years, 66% female, mean (SD) BMI of 32.3 (8.4) kg/m2 and 58% had severe asthma. Increasing exacerbation frequency was associated with adverse body composition and organ-specific changes (Figure). In age- and sex-adjusted models, participants with ≥3 exacerbations had significantly lower skeletal muscle density (12.1 vs. 18.3 HU; p = 0.002), greater IMAT area (4.2 vs. 3.6; p 0.001), and lower IMAT density (−53.8 vs. −51.3 HU; p 0.001). Visceral adiposity area was higher (8.9 vs. 7.6; p = 0.003), and liver attenuation was lower (47.2 vs. 52.5 HU; p = 0.02), consistent with increased hepatic fat. Total aortic calcification did not differ significantly across exacerbation groups (p = 0.44). Conclusion In a well-characterized asthma cohort, greater exacerbation burden was associated with adverse extra-pulmonary body composition, including reduced muscle density, increased intermuscular and visceral adiposity, and lower liver attenuation. These findings support a link between exacerbation frequency and systemic metabolic impairment in asthma, highlighting the potential utility of CT-derived body composition metrics as markers of disease severity. This abstract is funded by: None
Badhwar et al. (2026) conducted a cohort in Severe asthma (n=267). ≥3 asthma exacerbations vs. Fewer exacerbations was evaluated on Skeletal muscle density (HU) (p=0.002). In patients with severe asthma, ≥3 exacerbations in the preceding year were associated with adverse body composition, including lower skeletal muscle density (12.1 vs. 18.3 HU; p=0.002).