Increased prevalence of gastroesophageal reflux symptoms in patients with COPD

STUDY OBJECTIVES

To determine the prevalence of gastroesophageal reflux (GER) symptoms in patients with COPD and the association of GER symptoms with the severity of airways obstruction as assessed by pulmonary function tests (PFTs).

DESIGN

Prospective questionnaire-based, cross-sectional analytic survey.

SETTING

Outpatient pulmonary and general medicine clinics at a Veterans Administration hospital.

PATIENTS

Patients with mild-to-severe COPD (n = 100) were defined based on American Thoracic Society criteria. The control group (n = 51) consisted of patients in the general medicine clinic without respiratory complaints or prior diagnosis of asthma or COPD.

INTERVENTION

Both groups completed a modified version of the Mayo Clinic GER questionnaire.

RESULTS

Compared to control subjects, a greater proportion of COPD patients had significant GER symptoms defined as heartburn and/or regurgitation once or more per week (19% vs 0%, respectively; p < 0.001), chronic cough (32% vs 16%; p = 0.03), and dysphagia (17% vs 4%; p = 0.02). Among patients with COPD and significant GER symptoms, 26% reported respiratory symptoms associated with reflux events, whereas control subjects denied an association. Significant GER symptoms were more prevalent in COPD patients with FEV(1) < or %, as compared with patients with FEV(1) > 50% of predicted (23% vs 9%, respectively; p = 0.08). In contrast, PFT results were similar among COPD patients with and without GER symptoms. An increased number of patients with COPD utilized antireflux medications, compared to control subjects (50% vs 27%, respectively; p = 0.008).

CONCLUSIONS

The questionnaire demonstrated a higher prevalence of weekly GER symptoms in patients with COPD, as compared to control subjects. There was a trend toward higher prevalence of GER symptoms in patients with severe COPD; however, this difference did not reach statistical significance. We speculate that although GER may not worsen pulmonary function, greater expiratory airflow limitation may worsen GER symptoms in patients with COPD.

The role of pili in the attachment of Pseudomonas aeruginosa to unworn hydrogel contact lenses

Contamination of contact lenses is thought to increase the risk of infectious keratitis, yet factors promoting attachment of bacteria to contact lenses are not fully understood. It has been suggested that strains of Pseudomonas aeruginosa attach to mucosal surfaces via pili which are appendages found on some strains. This study investigated the role of pili and the effect of incubation time on the attachment of P. aeruginosa to 20 unworn hydrogel lenses representative of each of the four FDA categories. Ten lenses were incubated for 15 minutes and another ten for 180 minutes. Lenses were incubated with either PAK + P. aeruginosa which possessed pili or its isogenic mutant pair, PAK-, which was genetically similar except for the absence of pili. Bacteria were quantified, following homogenization of the contact lens, by viable counts. Non-piliated bacteria were significantly more likely to adhere to the lenses (p < 0.001). A significant interaction between lens type and incubation time was observed (p < 0.05); thus it is difficult to generalize about either of these effects in isolation. These results show that surface characteristics may confer an attachment advantage to bacteria.