Responsiveness to Parenteral Corticosteroids and Lung Function Trajectory in Adults with Moderate to Severe Asthma.

Rationale It is unclear why select patients with moderate to severe asthma continue to lose lung function despite therapy. We hypothesized that participants with the smallest responses to parenteral corticosteroids have the greatest risk of severe decline in lung function. Objective To evaluate corticosteroid response phenotypes as longitudinal predictors of lung decline. Methods Adults with in the NHLBI Severe Asthma Research Program (SARP3; (1, 2)) who had undergone a course of intramuscular triamcinolone at baseline and ≥2 annual follow-up visits were evaluated. Longitudinal slopes were calculated for each participant's post-bronchodilator FEV1% predicted. Categories of participant FEV1 slope were defined: severe decline, >2% loss/year; mild decline, >0.5 to 2.0% loss/year; no change, 0.5% loss/year to Measurements and main results Of 396 participants, 78 had severe decline, 91 had mild decline, 114 had no change, and 113 showed improvement. The triamcinolone-induced difference in the post-bronchodilator FEV1% predicted (tdFEV1; derived by baseline subtraction) was related to the 4-yr change in lung function or slope category in univariable models (p Conclusions Failure to improve the post-bronchodilator FEV1 after a challenge with parenteral corticosteroids is an evoked biomarker for patients at risk of severe decline in lung function.