Outcomes Associated With Early or Delayed Maintenance Treatment Post-Chronic Obstructive Pulmonary Disease Exacerbation

Study Overview
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Brief Summary
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The timing of initiating short-term treatment for COPD exacerbations with oral corticosteroids and/or antibiotic therapy has been shown to influence the recovery time of exacerbations with early initiation of exacerbation therapy having a faster symptom recovery compared to delayed initiation. While oral corticosteroids and/or antibiotic therapy are crucial for immediate exacerbation therapy, maintenance therapy with controller medications for COPD has been recommended to reduce the risk of future exacerbations. The initiation of maintenance therapy after a COPD exacerbation has been shown to be beneficial in the reduction of risk of future exacerbations. However, there is a lack of information on whether the timing of this initiation influences the risk of future exacerbations. The following study evaluates the impact of early versus delayed initiation of controller medication therapy for maintenance treatment following a COPD-related exacerbation on outcomes of future exacerbations and costs in patients with COPD.

Detailed Description
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Study period for this analysis will range from January 2003 through June 2009. Patients with at least one COPD exacerbation will be selected as the initial population. Three types of COPD exacerbations will be identified: 1) hospitalization with a primary discharge diagnosis code for COPD, 2) an emergency department (ED) visit with a primary diagnosis code for COPD, 3) physician visit with a dispensing of oral corticosteroid (OCS) or antibiotic (ABX) within 5 days of the visit. Only the first two will be selected as index exacerbations, which is defined as the first chronologically occurring exacerbation for a patient. For hospitalization exacerbations the discharge date of the hospitalization will be the index date and for ED exacerbations the date of the visit will be the index date. The pre-index period will be defined as the 1-year period before index date and the post-index period will be defined as 1-year period after index date. The enrollment period will thus range from January 1, 2004 through June 30, 2008. The post-index period will be used to identify the date of receipt of prescription for first COPD maintenance medication. This date of receipt will be used to compute the time to start maintenance treatment. Maintenance treatment refers to the use of controller medications. Specifically the study hypothesis for the primary outcome being tested was: Ho: There is no difference in risk of COPD-related hospitalization/ED visit between early and delayed cohorts Ha: There is a difference in risk of COPD-related hospitalization/ED visit between early and delayed cohorts Hypothesis for the key secondary outcome of COPD-related costs that was tested was: Ho: There is no difference in COPD-related costs between early and delayed cohorts Ha: There is a difference in COPD-related costs between early and delayed cohorts

Official Title
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Outcomes Associated With Early or Delayed Maintenance Treatment Post-Chronic Obstructive Pulmonary Disease Exacerbation

Conditions
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Pulmonary Disease, Chronic Obstructive

Intervention / Treatment
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* Drug: Early maintenance treatment
* Drug: Delayed Maintenance treatment


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: at least 40 years of age, continuously enrolled for medical and pharmacy benefits during their pre- and post-period diagnosis of COPD (ICD 491.xx, 492.xx, 496.xx) Exclusion Criteria: Patients were excluded if they had MTx in the pre-index period (to ensure inclusion of MTx-naïve patients) or if they received their first MTx during 181 to 365 days of the post-period (as dispensing of MTx unlikely to be related to the index exacerbation). Additionally, patients were excluded if they had any of the following comorbid conditions anytime during the study period: respiratory cancer, cystic fibrosis, fibrosis due to, bronchiectasis, pneumonociosis, pulmonary fibrosis, pulmonary tuberculosis, or sarcoidosis, and also if they had other doses (unapproved in the US) of fluticasone propionate-salmeterol xinafoate combination (100/50 mcg or 500/50 mcg) or budesonide dipropionate-formoterol fumarate fixed dose combination (any dose).

Ages Eligible for Study
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Minimum Age: 40 Years

Sexes Eligible for Study
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All

Study Plan
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How is the study designed?
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Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Patients diagnosed with COPD<br>Patients diagnosed with COPD using ICD codes with a COPD-related exacerbation and receiving maintenance therapy | Drug: Early maintenance treatment<br>* Various classes of COPD maintenance treatment initiated within 30 days post index COPD exacerbation (hospitalization/ED visit)<br>Drug: Delayed Maintenance treatment<br>* Various classes of COPD maintenance treatment initiated after 30 days post index COPD exacerbation (hospitalization/ED visit)<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| COPD hospitalization/ED visit | Risk and number of COPD exacerbations will be computed in the post-index period. Hospitalization with a primary discharge diagnosis code (ICD code 491.xx, 492.xx, and 496.xx) for COPD. ED visit will be defined as COPD related if accompanied by diagnosis code for COPD. | Up to 6 years (January 1, 2003 through June 30, 2009) | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| COPD-related ED visit | The risk and proportion of patients with a COPD-related exacerbation requiring ED visit was defined as a COPD-related ED visit. | Up to 6 years (January 1, 2003 through June 30, 2009) | 
| COPD-related hospitalization | risk and number of COPD hospitalizations will be computed in the post-index period. Hospitalization with a primary discharge diagnosis code (ICD code 491.xx, 492.xx, and 496.xx) for COPD will be captured. | Up to 6 years (January 1, 2003 through June 30, 2009) | 
| COPD-related Phy+Rx visit | Risk and number of COPD-related physician office visit with a dispensing for oral corticosteroid (OCS) or antibiotic (ABX) within 5 days of the visit | January 1, 2003 through June 30, 2009 (up to 6 years) | 
| COPD related Costs | COPD related medical, pharmacy and total costs. Costs were standardized to 2009 US dollars (USD) using consumer price index for US medical care. | January 1, 2003 through June 30, 2009 (up to 6 years) |