Veterans who smoke but have preserved lung function who have high chronic obstructive pulmonary disease (COPD) assessment scores do not appear to use health care resources as frequently as patients with established COPD, indicating the high score may be unrelated to respiratory function, according to recent research presented at the 2019 American Thoracic Society meeting in Dallas, Texas.

“The COPD Assessment test (CAT) score is a validated questionnaire developed to measure symptoms in subjects with COPD. However, it has been shown that its application to smokers with preserved lung function (SPLF) can disclose a symptomatic group (defined as a CAT score of ≥10) with increased rates of exacerbations and respiratory medication utilization compared to less symptomatic subjects with established COPD,” Andrea Guerrero Cignarella, MD, from the University of Miami in Miami, Florida, and colleagues wrote in their abstract. “We sought to determine whether these findings are replicated in the veteran population.”

Lung illustration. Source: Getty

Dr. Guerrero Cignarella and colleagues examined CAT scores from veterans at the Miami Veterans Affairs (VA) Medical Center who received pulmonary function testing (PFT) and patients with established COPD. Patients were categorized as smokers if they had a history of 10 packs or more per year and had preserved lung function if forced expiratory volume in 1 second (FEV1)/forced vital capacity (FVC) score was 0.70 or more after bronchodilator use. A CAT score of 10 or higher was considered a high score in the study. The researchers also reviewed the charts of the veterans for information on health care resource use, which was defined as visits to the emergency room visits, hospitalizations and use of medication.

Overall, there were 656 participants studied, and high CAT score prevalence was 83.9% among patients with COPD compared with 70.9% among smokers with preserved lung function (SPLF) with similar mean CAT scores between COPD and SPLF patients (17.82 vs. 16.41; P = .086). Patients with COPD had higher phlegm production (P ≤ .001), rate of frequent coughing (P = .025) and emergency room visits related to respiratory issues (0.34 vs. 0.03; P =.02) in COPD patients with higher CAT scores compared with the SPLF group.

However, SPLF patients with high CAT scores were more likely to be prescribed respiratory medication than those with low CAT scores (49.1% vs. 24.2%; P =.01) compared with patients in the COPD group, where there were no significant differences in respiratory medication prescription between patients with high and low CAT scores. The researchers compared SPLF medication use among patients who had high CAT scores with COPD patients who had low CAT scores and found 72.2% of COPD group were prescribed respiratory medication compared with 49.1% of SPLF patients (P = .01). In addition, there were no significant between-group differences with regard to emergency room visits (0.03 vs. 0.08; P = .770).

“The drivers for these high scores are mostly not respiratory related,” Dr. Guerrero Cignarella and colleagues wrote. “Contrary to other observations, SPLF with high CAT scores do not have higher healthcare utilization than COPD subjects with low scores.”