New Tool Uses Data to Predict Which Patients Have Higher Risk for Increased COPD Exacerbations

March 23, 2020

This study examined risk of exacerbation using a new predictive tool called COPD treatment ratio.

Using a new predictive tool was effective in identifying patients with chronic obstructive pulmonary disorder (COPD) who are at increased risk for severe exacerbation, according to a paper in the journal of the COPD Foundation: Chronic Obstructive Pulmonary Diseases.

Investigators from North Carolina and Minnesota conducted a retrospective observational study that included more than 60,000 patients in order to compare what they call a COPD treatment ratio (CTR); the comparison involved a validated CTR vs. other COPD exacerbation predictors like prior exacerbation and rescue and maintenance medication use. Exacerbations can be experienced by patients with COPD at all stages of disease severity and can impact quality of life as well as increased morbidity and mortality. Exacerbations also account for 85% of direct medical costs due to COPD, the study authors added.

There are exacerbation models that exist, but the CTR is a new type of risk score and modifiable measure, the investigators explained. It combines accessible prescription data collected from health insurance claims without the need for patient history data, the authors said. According to the paper, CTR “is defined as the total units (30-day equivalent) of maintenance medication dispensed, divided by total units of maintenance plus rescue medications dispensed.”

The patients were Medicare Advantage Part D beneficiaries with COPD who were treated between 2011 and 2016. Of those patients, almost 50,000 had no exacerbation and about 11,000 had 1 or more severe exacerbation during the at-risk period.

Patients who experienced 1 or more severe exacerbation during the at-risk period used significantly more COPD medications compared to those who experienced no exacerbation, the investigators found. This included frequent systemic corticosteroid use, use of 2 or more maintenance medication classes, and frequent rescue medication use. These patients also experienced significantly more baseline COPD exacerbations and had more chronic oxygen therapy and nebulizer procedures during the period, the study authors continued.

“While previous exacerbation was the strongest predictor for future exacerbation, the CTR was an effective measure for identification of people diagnosed with COPD who are at increased risk of severe exacerbation,” the study authors wrote.

Some of the advantages of CTR over other tools includes that it pulls from pharmacy data. This type of information is readily accessible, the study authors said, and can be calculated even in the absence of other types of data. Being a modifiable risk factor also helps, as individuals with a low ratio of maintenance medication to rescue medication can be identified and then their ratios can be increased with a focus on reducing their overall use of rescue medication. CTR is also useful as a guide for organizations to make decisions about whether to intervene and dedication services to exacerbation prevention, the investigators said.

CTR has been proven effective in other retrospective studies that used health insurance data, but the investigators noted that those studies were made up of a mix of both Medicare and commercial insurance patients.

“While the CTR does not predict severe exacerbation as well as the presence of a prior exacerbation, the CTR can measure the risk of exacerbation in patients without a history of exacerbations, and can be assessed without the need for medical history; in addition, it can be used to modify patient management appropriately, particularly in low resource settings,” the study authors concluded. “Overall, the CTR is an effective tool for predicting severe exacerbation risk and performed similarly to other pharmacy-based predictors explored in this study.”

Reference

Stanford RH, Korrer S, Brekke L, Reinsch T, Bengtson LGS. Validation and assessment of the COPD treatment ratio as a predictor of severe exacerbations. Chronic Obstr Pulm Dis. 2020; 7(1): 38-48. doi: 10.15326/jcopdf.7.1.2019.0132.