What Did 3 Years of Data from the Czech National COPD Database Reveal?

Occurrence of individual COPD phenotypes

Regarding the occurrence of COPD phenotypes, bronchitic and emphysematous phenotypes prevailed (both occurring in approximately 2/3 of patients, with similar representation and some overlap), about 1/5 were patients with frequent exacerbations, more than 1/10 had asthma-COPD overlap, and other phenotypes were less frequently represented. The Czech evaluation of phenotypes includes overlaps, and it is therefore necessary to consider that the treatment of one phenotype can influence the treatment of another. In recent years, this approach has been applied because it is more suitable from the perspective of managing the care of these patients.

Most physicians treating patients included in the database utilized Czech recommendations, which state that all COPD patients should receive basic treatment and patients with a certain phenotype should receive appropriate phenotype therapy. 

Mucolytic treatment concerning the disease phenotype

The Czech COPD database shows the proportion of various pharmacotherapy options used: 22% of all subjects received mucolytics, most participants were treated with bronchodilators, a relatively large portion with inhaled corticosteroids, and about half with theophylline. Thus, mucolytic treatment was used by just under a quarter of the entire cohort regardless of the occurrence of individual phenotypes:

• Of the patients with the bronchitic phenotype, 30% were receiving mucolytic treatment already at the start of the monitoring in this database (significantly more than the data of the whole cohort indicates). These patients were thus treated in accordance with the Czech recommendations for COPD therapy, as according to those, mucolytic therapy is appropriate for patients with the bronchitic phenotype, frequent exacerbations phenotype, and COPD-bronchiectasis overlap phenotype.
• For patients with the emphysematous phenotype, the proportion of mucolytic treatment was roughly the same as in the entire cohort, not less as might be expected. The speaker sees the reason for this in the fact that the emphysematous phenotype also included patients with phenotype overlaps.
• For patients with frequent exacerbations, mucolytic treatment was used significantly more often than for patients without frequent exacerbations. Mucolytic treatment is clearly preferred for them and is essentially prescribed more often than for patients with other phenotypes.
• For patients with asthma-COPD overlap, mucolytic therapy was used much less frequently than for the rest of the cohort.
• For patients with COPD-bronchiectasis overlap, mucolytic treatment was, in accordance with the recommendations, used much more frequently than for those without bronchiectasis.

Thus, before the start of monitoring, the phenotype approach in treatment was already being used by Czech physicians according to national recommendations.

Analysis of treatment results over the first 3 years

Mucolytic treatment is given more often to patients with severe COPD. Patients with stage IV COPD receive mucolytic treatment almost twice as often as patients with stage II. The difference is even more pronounced when patients are divided into individual groups according to GOLD criteria: Patients with the most severe COPD (GOLD D) were treated with mucolytic therapy most frequently.

The effect of individual drugs, including mucolytics, was evaluated over time. The monitoring is ongoing, and only the first analyses are available so far, with evaluations of the entire 5 years available later. At the time of the Hradec Pulmonology Days in 2022, analyses from the first 3 years were available, and these already show some interesting data:

• In patients with the bronchitic phenotype using mucolytic treatment, a dramatic reduction in the frequency of exacerbations was observed.
• In patients with frequent exacerbations, there was also a decrease in exacerbations, but not as pronounced. Several treatment modalities influenced the reduction of exacerbations in patients with this phenotype, suggesting that different exacerbation types exist—some patients always need corticosteroids, while others respond much better to mucolytic therapy.
• In patients with COPD and bronchiectasis overlap, mucolytic treatment had a dramatic effect on the frequency of exacerbations. Users of mucolytic therapy with this phenotype achieved significantly better results than patients who did not receive it.

Conclusion

Currently, analyses of other parameters (the effect of mucolytic treatment on dyspnea, symptoms, etc.) are being conducted. The 5-year monitoring analyses aim to evaluate the effect on more specific symptoms (cough, expectoration) in patients using mucolytic therapy. Regarding symptom effects and other outcomes, further, more detailed evaluations are expected to follow.

The speaker concluded that based on current knowledge, it can already be said that mucolytic drugs are certainly preferred in patients with certain phenotypes in accordance with the Czech national guidelines and in patients with severe COPD, i.e., according to severity, stages, or more severe groups according to GOLD. Although these are the first data to be refined further, it appears that mucolytic treatment reduces the frequency of exacerbations in COPD patients.

Eva Srbová
editorial team MeDitorial