Relationship of Peripheral Blood Counts with Asthma Control

To determine the association between blood eosinophil and neutrophil counts with asthma control.

This retrospective study, conducted in tertiary care hospital of western India, evaluated the hospital electronic medical record (HEMR) of children aged 5 to 18 y who were diagnosed with asthma as per the Global Initiative for Asthma (GINA) guidelines in the pediatric chest clinic (PCC). Eosinophil and neutrophil counts were recorded from HEMR and asthma control was determined as per the GINA guidelines on follow-up.

A total of 742 children attended the PCC in the last 2 y from March 2017 to February 2019; out of which, blood eosinophil and neutrophil counts were done in 116 children with asthma. The median eosinophil and neutrophil count were 0.46 (0.13, 0.78) × 10⁹/L and 5.08 (3.50, 7.53) × 10⁹/L cells, respectively. Eosinophil count was significantly higher in children with well-controlled asthma as compared to partly/uncontrolled asthma [median eosinophil count 0.46 (0.13, 0.78) vs. 0.40 (0.1, 0.66) × 10⁹/L; p = 0.04]; while the neutrophil count was significantly higher in children with partly/uncontrolled asthma as compared to well-controlled asthma [median neutrophil 6.54 (4.32, 7.92) vs. 4.85 (2.96, 6.86) × 10⁹/L; p = 0.04].

High lung function is associated with good asthma control. Although not independently associated, the high absolute eosinophil counts (AEC) is associated with better asthma control, while high absolute neutrophil counts (ANC) is associated with poor asthma control.