Those With GOLD A or B COPD and 1 Exacerbation Have Increased Exacerbation Risk

Among patients with chronic obstructive pulmonary disease (COPD) in Global Initiative for Chronic Obstructive Lung Disease (GOLD) categories A and B, those who had 1 exacerbation (vs no exacerbations) in the previous year had a significantly increased risk for future exacerbations and respiratory hospitalizations, according to a study in the American Journal of Respiratory and Critical Care Medicine.

Researchers in Sweden assessed the risk for future exacerbations, hospitalizations, and mortality in patients with COPD based on their GOLD category and exacerbation history during the prior year. Study participants were at least 30 years of age and were registered in the Swedish National Airway Register (SNAR) from January 2017 to August 2020, with a primary physician diagnosis of COPD.

The patients were stratified based on GOLD criteria for groups A, B, and E according to symptom burden and exacerbation history. GOLD A and B patients were further categorized as GOLD A0 and B0 if they had not experienced an exacerbation within 1 year before the index date and as GOLD A1 and B1 if they had experienced only 1 moderate exacerbation within 1 year before the index date.

Primary outcomes were moderate exacerbation; all-cause, respiratory, and cardiovascular hospitalization; and all-cause, respiratory, and cardiovascular mortality. The participants were followed to January 2021.

A total of 45,350 patients (mean age, 71.5 [SD 9.1] years; 57% female) in the SNAR database were found eligible for analysis. The GOLD A0 group had 11,232 patients, the GOLD A1 group had 1730, the GOLD B0 group had 20,017, the GOLD B1 group had 4442, and the GOLD E group had 7929.

The participants were followed for a median of 1.8 years (interquartile range [IQR], 1.2-2.5) for all-cause mortality (85,910 person-years), 1.3 years (IQR, 0.8-2.0) for all-cause hospitalization, and 1.3 years (IQR, 0.7-2.0) for moderate exacerbations.

Moderate exacerbations, all-cause respiratory and cardiovascular hospitalizations, and mortality increased with a greater number of symptoms and exacerbations (from GOLD A0 group to GOLD E group).

The exacerbation incidence in events/patient-years was 0.16, 0.51, 0.24, 0.65, and 1.55 in the GOLD A0, GOLD A1, GOLD B0, GOLD B1, and GOLD E groups, respectively. All-cause hospitalization incidence (events/patient-year) was 0.22, 0.27, 0.34, 0.41, and 0.70 in the GOLD A0, GOLD A1, GOLD B0, GOLD B1, and GOLD E groups, respectively. All-cause mortality rates were 5.6%, 5.5%, 10.3%, 12%, and 21% in the GOLD A0, GOLD A1, GOLD B0, GOLD B1, and GOLD E groups, respectively.

In adjusted incidence rate ratios (RRs) for groups A1, B0, B1, and E vs A0, higher rates of moderate exacerbations, all-cause hospitalization, and respiratory hospitalization occurred in all 4 groups compared with A0. Adjusted RRs for exacerbations were 3.08 (95% CI, 2.75-3.46) for A1, 1.40 (95% CI, 1.32-1.50) for B0, 3.60 (95% CI, 3.32-3.91) for B1, and 8.60 (95% CI, 8.02-9.22) for E compared with A0.

In adjusted HRs for group B1 vs B0, group B1 had an increased HR of future exacerbation (2.56; 95% CI, 2.40-2.74), all-cause hospitalization (1.28; 95% CI, 1.21-1.35), and respiratory hospitalization (1.44; 95% CI, 1.27-1.62), but not all-cause mortality (1.04; 95% CI, 0.91-1.18) or respiratory mortality (1.13; 95% CI, 0.79-1.64) than group B0.

Among several limitations, a considerable number of patients in SNAR were excluded because of missing data, and cause-of-death registries may have questionable validity in some situations. Also, some exacerbations might have been treated with antibiotics alone without corticosteroids, or a course of corticosteroids could have been prescribed for another reason than exacerbation.

“Stratification of GOLD A and B patients on having had 1 or no exacerbation in the last year thus provides valuable information for future risk, which should influence treatment recommendations for effective preventive strategies,” concluded the study authors.