Continued ICS treatment for COPD may not be appropriate for patients with high eosinophil count

The overall effect of continued use of inhaled corticosteroid (ICS) in patients with chronic obstructive pulmonary disease (COPD) appears to increase commensurate with the blood eosinophil (EOS) count, a study has found.

Researchers performed a systematic review of randomized controlled trials (RCT) of ICS treatment in patients with COPD (≥40 years, no current asthma), where outcomes were analysed by EOS count (<150, 150–300, >300 cells/μl) and where >50 percent of patients had prior ICS exposure. They searched multiple online databases and identified 11 RCTs involving a total of 29,654 patients.

Across the studies included, the duration of the interventions ranged from 24 to 52 weeks. The populations were predominantly male (60–80 percent), with an average age of 63–65.3 years and average body mass index (BMI) of 25.11–27.98 kg/m². About 40–70 percent of the patients were current smokers, and the COPD severity, evaluated using the GOLD classification, was mild in 0 percent, moderate in 32 percent, severe in 52 percent, and very severe in 16 percent.

Pooled data showed a significant difference in the reduction of risk of moderate to severe exacerbation across the three EOS count subgroups (p<0.00001). The corresponding rate ratios were 0.88 (95 percent confidence interval [CI], 0.83–0.94) with <150 cells/μL, 0.80 (95 percent CI, 0.69–0.94) with 150–300 cells/μL, and 0.57 (95 percent CI, 0.49–0.66) with >300 cells/μL.

The certainty of the effect estimates was deemed low to very low due to the risk of bias, unexplained heterogeneity, few RCTs, and wide CIs.

Nevertheless, the findings suggest that treatment with ICS is beneficial except in patients with EOS count below 150 cells/μl.