Alone, bronchiectasis and chronic obstructive pulmonary disease (COPD) can be difficult to diagnose and treat, but together they are much more difficult. Since bronchiectasis appears to be more common in patients with COPD, a group of researchers from Shanghai Pulmonary Hospital’s Tongji University School of Medicine were interested in studying how bronchiectasis could be predicted in patients with COPD. They found that the presence of Pseudomonas aeruginosa was most predictive of bronchiectasis, and that bronchiectasis was predictive of a worse outcome for COPD.

According to the study, “The Existence of Bronchiectasis Predicts Worse Prognosis in Patients with COPD,” which was published in Scientific Reports, COPD incidence is on the rise in at least 12 countries. Since COPD may be predictive of bronchiectasis, the researchers were concerned that bronchiectasis might also be on the rise. By establishing risk factors common to COPD patients and bronchiectasis, early diagnosis and subsequent treatment may be more possible.

Nearly 900 inpatients with COPD in five years at Shanghai Pulmonary Hospital were part of the retrospective study. A diagnosis of COPD required a forced expiratory volume in one second (FEV1) over forced vital capacity (FVC) of less than 70% and a long history of smoking. To confirm the diagnosis, chest high resolution computed tomography (HRCT) scans were obtained. A diagnosis of bronchiectasis required three fulfillment criteria established previously. These were a lack of tapering of the bronchi, dilation of the bronchi, or visualization of the peripheral bronchi near the walls of the lungs. For all patients, with or without bronchiectasis, blood samples and sputum samples were analyzed for clinical biomarkers.

Within the patients sampled, the only preexisting conditions that might trigger bronchiectasis were nasosinusitis, tuberculosis, and pneumonia. Of all 896 patients, 311 (34.7%) had bronchiectasis. Considering patient history, bronchiectasis tended to appear in older males with a long duration of symptoms, greater sputum expectoration, and greater systemic inflammation. A mathematical model showed that independent predictors were P. aeruginosa infection, purulent sputum production, onset of symptoms, and length of hospitalization.

“Our study also found several factors in addition to those already known to be associated with an increased risk of all-cause mortality in patients with COPD, such as decreased pulmonary function and the subsequent complications,” stated the authors. “Specifically, the presence of bronchiectasis, the isolation of potentially pathogenic microorganisms, and the patient’s age were associated with an increased risk in all-cause mortality in patients with COPD.” In other words, for a case that seems to be “chicken or the egg,” COPD may be predictive of bronchiectasis, which may be predictive of a worse COPD outcome.