The presence of a type of bacteria called Pseudomonas aeruginosa in Chinese patients with bronchiectasis was found to be associated with worse lung function, a higher risk for all-cause mortality, and lower quality of life, a study shows.
Results were published in the study, “Pseudomonas aeruginosa isolation in patients with non-cystic fibrosis bronchiectasis: a retrospective study,” in the journal BMJ Open.
Bronchiectasis is a chronic inflammatory respiratory disorder characterized by injury to lung tissue, structural damage to the airways, and bacterial infection. Studies have shown that P. aeruginosa is prevalent in patients with the disease and is associated with a rapid decline in lung function.
In fact, two different grading schemes indicate that colonization by P. aeruginosa is a risk factor for early death, more frequent exacerbations, and hospitalization.
Few studies have correlated P. aeruginosa colonization with clinical outcomes in Chinese patients, so researchers set out to determine the characteristics and prognostic value of P. aeruginosa colonization in a Chinese population.
A retrospective study was conducted using clinical data from 1,188 bronchiectasis patients to assess mortality, frequency of exacerbations, and quality of life. Patients were diagnosed at the Shanghai Pulmonary Hospital between January 2011 and December 2012.
Of those patients, 536 patients — or 45.1 percent — tested positive for pathogens. Results showed that P. aeruginosa was the most common pathogen, found in 232 patients, followed by the bacterium Aspergillus in 75 patients, and Candida albicans in 72 patients.
Patients with P. aeruginosa exhibited poorer lung function than patients without the bacterium, as measured by FEV1% (forced expiratory volume in one second), FVC% (forced vital capacity) and FEV1/FVC — all common and relevant indicators of lung function.
The presence of P. aeruginosa was also associated with a more than threefold risk for all-cause mortality, compared with patients without the bacterium. Additionally, the bacterium was connected to a high rate of exacerbations — defined as three or more exacerbations per year — putting affected patients at a more than 2.4 times higher risk than those without it.
Researchers then assessed quality of life using the Hospital Anxiety and Depression Scale, which indicated that patients with P. aeruginosa had significantly worse scores than patients without it.
Other quality of life questionnaires — including the Leicester Cough Questionnaire and the modified Medical Research Council scale — also showed worse scores for patients with P. aeruginosa.
Researchers concluded that the presence of “P. aeruginosa in patients with bronchiectasis is a significant prognostic indicator and should be a major factor in the clinical management of the disease.”