Bronchiectasis plus chronic respiratory infection raises exacerbation risk

Key takeaways:

• Common chronic infections in bronchiectasis involved Pseudomonas aeruginosa and Mycobacterium avium complex.
• More patients with a P. aeruginosa vs. M. avium complex infection had exacerbations.

Having a chronic respiratory infection in addition to bronchiectasis heightened the risk for an exacerbation and hospitalization within 2 years of diagnosis, according to results published in BMC Pulmonary Medicine.

“We found a high prevalence of infections and severe outcomes in a nationally distributed population of persons with bronchiectasis, who are likely more representative of all persons with bronchiectasis compared with those enrolled in specialized registries at tertiary care centers,” Samantha G. Dean, BA, fourth-year biostatistics PhD student at Yale University’s School of Medicine, and colleagues wrote.

Through the large, geographically diverse Cerner HealthFacts Electronic Health Record database, Dean and colleagues evaluated 7,749 patients (65% aged 65 years or older; 65% women) with incident bronchiectasis to determine the type and frequency of pulmonary infections experienced by this population, as well as how these infections impact exacerbation and hospitalization rates.

In addition to bronchiectasis, 50% of the total cohort had COPD. Some patients with bronchiectasis also suffered with asthma (35%) or lung cancer (7%) at the same time, researchers noted.

After analyzing the organisms in pulmonary samples from 56% of the total cohort, researchers found Pseudomonas aeruginosa in 937 (12%) patients, of whom 219 (23%) had chronic colonization.

Researchers observed three additional common organisms in the samples, all of which appeared less frequently than P. aeruginosa: Staphylococcus aureus (n = 502; 6%), Mycobacterium avium complex (MAC; n = 336; 4%) and Aspergillus species (n = 288; 4%).

A chronic MAC infection appeared in 101 (30%) patients with a minimum of one isolate of this pathogen. Smaller proportions of patients had chronic Aspergillus species infection (17%; n = 50) or chronic S. aureus colonization (15%; n = 74).

Other organisms found included Haemophilus influenzae, Stenotrophomonas maltophilia, Streptococcus pneumoniae, Klebsiella pneumoniae and Mycobacterium abscessus.

In terms of exacerbation and hospitalization rates, researchers had data from 2 years after the bronchiectasis diagnosis for 5,795 patients.

During this timeframe, hospitalization frequently occurred (60%), whereas fewer patients (32%) experienced an exacerbation.

Researchers observed a significantly greater proportion of hospitalized patients in the 2-year period among those with bronchiectasis plus chronic P. aeruginosa vs. MAC (87% vs. 64%: P < .0029).

For those with chronic P. aeruginosa, the median total hospitalization duration was 32.6 days, whereas patients with chronic MAC and patients with no chronic infection had a shorter duration (10.9 days and 11.7 days, respectively).

Further, more patients with bronchiectasis plus chronic P. aeruginosa vs. MAC suffered an exacerbation (64% vs. 38%; P < .0064).

At the 2-year mark, the risk for exacerbations went up by 70% if patients with bronchiectasis also had a chronic infection with any of outlined organisms vs. no chronic infection. Researchers found a similar outcome when evaluating the risk for hospitalization at 2 years, which was heightened by 50% with a chronic infection.

“These findings [speak] to the need for continued monitoring of lung infections among all persons with bronchiectasis,” Dean and colleagues wrote.