Objectives: To examine the impact of timing of maintenance treatment initiation (early vs delayed) on risk of future exacerbations and costs in chronic obstructive pulmonary disease (COPD) patients.
Study design: Retrospective cohort design using data (January 1, 2003, through June 30, 2009) from a large, US-based integrated pharmacy and medical claims database.
Methods: Administrative claims from January 1, 2003, through June 30, 2009, were used. Methotrexate (MTx)-naïve patients (aged >40 years) with at least 1 COPD-related hospitalization/emergency department (ED) visit were included (discharge date was index date). Patients initiating MTx within the first 30 days and 31 to 180 days post-index were classified into early and delayed cohorts, respectively. Clinical and economic outcomes related to COPD exacerbations were assessed for 1 year post-index and compared between cohorts using regression models controlling for baseline characteristics. The incremental effect on outcomes of every 30-day delay in MTx initiation up to 6 months after the index event was also assessed.
Results: The majority of the 3806 patients (78.6%) received early MTx. A significantly higher proportion of patients in the delayed cohort had a COPD-related hospitalization/ED visit compared with the early cohort (25.6% vs 18.0%; P <.001). After controlling for baseline differences, the delayed cohort had a 43% (P <.001) higher risk of a future COPD-related hospitalization/ED visit compared with the early cohort. Every 30-day delay was associated with 9% risk increase (P = .002). Treatment delay also increased COPD-related costs ($5012 vs $3585; P <.001).
Conclusion: Early MTx initiation is associated with reduced risk of future COPD exacerbations and lower costs.