Impact of gastro-oesophageal reflux disease symptoms on COPD exacerbation.

BACKGROUND The association between gastro-oesophageal reflux disease (GORD) and chronic obstructive pulmonary disease (COPD) exacerbation has so far remained unclear. OBJECTIVE To prospectively establish the clinical significance of GORD symptoms on exacerbation. METHODS 82 patients with COPD and 40 age matched controls were enrolled in this study. Symptoms were evaluated by a questionnaire using the Frequency Scale for the Symptoms of GORD (FSSG). Patients with COPD were prospectively surveyed for 6 months, and episodes of exacerbation were identified using a diary based on modified Anthonisen's criteria. Exhaled breath condensate (EBC) pH was measured in both groups, and induced sputum was evaluated in patients with COPD. RESULTS Positive GORD symptoms were reported in 22 (26.8%) patients with COPD and in five (12.5%) controls (p = 0.10). The frequency of exacerbations was significantly associated with the FSSG score (p = 0.03, r = 0.24, 95% CI 0.02 to 0.43). Multiple regression analysis revealed that GORD symptoms were significantly associated with the occurrence of exacerbations (p<0.01; relative risk 6.55, 95% CI 1.86 to 23.11). EBC pH was inversely correlated with FSSG score in both groups (p = 0.01, r = -0.37, 95% CI -0.55 to -0.14 in patients with COPD, and p<0.01, r = -0.45, 95% CI -0.67 to -0.16 in control subjects). CONCLUSIONS GORD symptoms were identified as an important factor associated with COPD exacerbation.