Late Breaking Abstract - Blood eosinophils in inhaled steroid dose titration

Whilst it is known that titrating inhaled corticosteroid (ICS) dose against sputum eosinophils improves asthma control, the effect of increasing ICS dose on blood eosinophils are uncertain. We explored if ICS dose titration suppresses blood eosinophil counts and exhaled nitric oxide (FeNO) in patients with asthma, and whether leukotriene receptor antagonists (LTRA) had additive effect.14 studies were pooled for analysis: n=217, non-smoking, mild-moderate persistent asthmatics, mean age of 38 years, and a mean FEV1 of 85% predicted. Patients received ICS dose titration from a baseline of none or low dose ICS [median 200 µg/day beclometasone diproprionate (BDP) equivalent]; to medium dose ICS (median 800 µg/day), with a median treatment duration of two weeks. Of these n=144 received a median of two weeks additive LTRA. Baseline mean eosinophils were 356 cells/µL, and mean exhaled nitric oxide (FeNO) was 41.36 ppb.Results are presented in figure 1. We observed a significant mean fall in eosinophils of 71 cells/µL (95% CI 38 to 105) p=0.001 comparing low versus medium dose ICS, LTRA amounted to a non-significant 20 cells/µL further fall. FeNO also significantly fell by 14.5ppb (95% CI 7.9 to 21.1), p=0.001 comparing low and medium dose ICS. FEV1% predicted did not significantly change with ICS dose increase: 1.6% (95% CI -0.5 to 3.2).ICS even at a medium dose of 800ug BDP results in a significant fall in blood eosinophils over two weeks.
Source: European Respiratory Journal - Category: Respiratory Medicine Authors: Tags: Airway Pharmacology and Treatment Source Type: research