Bronchiectasis Exacerbation Before First ASCCVD Event Linked to Higher Mortality

Patients who have a hospitalization or emergency room visit for bronchiectasis exacerbation prior to an initial atherosclerotic cardiovascular disease (ASCaVD) or atherosclerotic cerebrovascular disease (ASCeVD) event are at increased risk for mortality, according to study findings published in Therapeutic Advances in Respiratory Disease.

Although bronchiectasis has been linked to increased incidence of ASCaVD and ASCeVD, the effect of bronchiectasis on mortality from these diseases in unclear. Researchers therefore sought to assess the effects of bronchiectasis exacerbation prior to ASCaVD or ASCeVD events on mortality, using data from the South Korean National Health Insurance Service-National Sample Cohort (NHIS-NSC) database from 2002 through 2015.

Patients with bronchiectasis were divided into 2 cohorts, depending on whether they had experienced a first-time event related to cardiovascular vs cerebrovascular disease; the ASCaVD cohort included 1066 patients (78.1% aged ≥60 years; 50.2% male), and the ASCeVD cohort included 825 patients (87.3% aged ≥60 years; 52.2% female). The patients were classified as “exacerbators” and “nonexacerbators” based on whether or not their records indicated they had experienced a moderate bronchiectasis exacerbation within 1 year before the index ASCaVD or ASCeVD event; the ASCaVD cohort included 149 (13.9%) exacerbators vs and 112 (13.6%) in the ASCeVD cohort. The mean follow-up was 4.1 years in the ASCaVD group and 3.4 years in the ASCeVD group.

The primary outcomes were 90-day, 1-year, and all-cause mortality. All participants were followed up from the admission date of index events until death or December 31, 2015, whichever came first. In the ASCaVD cohort, 90-day mortality, 1-year mortality, and all-cause mortality were greater in exacerbators compared with nonexacerbators. In the ASCeVD cohort, all-cause 1-year mortality and all-cause mortality were higher in exacerbators than in nonexacerbators; 90-day mortality was greater in exacerbators but without statistical significance.

In the ASCaVD cohort, moderate bronchiectasis exacerbation was independently associated with an increased risk of 90-day mortality (odds ratio [OR] 2.27; 95% CI, 1.26-4.10; P =.007), 1-year mortality (OR 3.30; 95% CI, 2.03-5.38; P <.001), and all-cause mortality (hazard ratio [HR] 1.78; 95% CI, 1.35-2.34; P <.001). Age and Charlson comorbidity index score also were significant risk factors for 90-day, 1-year, and all-cause mortality.

In the ASCeVD group, moderate bronchiectasis exacerbation significantly increased the 90-day mortality risk (OR 1.73; 95% CI, 0.94-3.19), 1-year mortality risk (OR 1.79; 95% CI, 1.07-3.00; P =.027) and all-cause mortality risk (HR 1.47; 95% CI, 1.10-1.95; P =.009). Age was an additional significant risk factor for mortality.

Those who had experienced an exacerbation within 1 year of their index ASCaVD or ASCeVD event had decreased survival compared with that of those who had not experienced a bronchiectasis exacerbation in this time frame in all analyses except for 90-day survival in the ASCeVD cohort.

Notably, exacerbators in both cohorts were older and had lower body mass index (BMI), more chronic airway diseases such as asthma and chronic obstructive pulmonary disease (COPD), and more comorbidities according to the Charlson comorbidity index (CCI). Older age and lower BMI also were significant risk factors for 90-day, 1-year, and all-cause mortality in both groups.

Among several limitations, the data were obtained from administrative claims and only patients who were hospitalized with ASCaVD and ASCeVD were included. Also, the results cannot be applied to patients with multiple hospitalizations for atherosclerotic cardiovascular and cerebrovascular disease (ASCCVD), and the NHIS-NSC did not provide data on participants’ smoking status. In addition, the severity of bronchiectasis was not considered because bronchiectasis severity index was not assessed owing to the absence of clinical data.

“Hospitalization or emergency room visit for bronchiectasis exacerbation within

1 year before ASCaVD or ASCeVD is associated with an increased ASCaVD- or ASCeVD-associated mortality,” study authors concluded. “This study also highlights the importance of preventing exacerbation in patients with bronchiectasis to reduce the subsequent ASCCVD-related mortalities,” the researchers added.